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Univerzitet u Beogradu
1.
Kalezić, Tanja V., 1977-.
Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih.
Degree: Medicinski fakultet, 2017, Univerzitet u Beogradu
URL: https://fedorabg.bg.ac.rs/fedora/get/o:16658/bdef:Content/get
► Medicina - Oftalmologija / Medicine - Ophthalmology
Kornealna topografija sa prikazanim svim parametrima različitih mapa za praćenje promena oblika rožnjače nov su korak ka boljem…
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▼ Medicina - Oftalmologija / Medicine -
Ophthalmology
Kornealna topografija sa prikazanim svim
parametrima različitih mapa za praćenje promena oblika rožnjače nov
su korak ka boljem razumevanju rožnjače, kao i boljem sagledavanju
pacijenata za različite oftalmološke procedure. Cilj istraživanja
bio je da se ustanovi uticaj dejstva različitih cikloplegika i
ciklokonstriktora na promenu parametara zakrivljenosti oblika i
debljine rožnjače. Metod. Istraživanje je obavljeno na Klinici za
očne bolesti Kliničkog centra Srbije Medicinskog fakulteta
Univerziteta u Beogradu, u periodu od 2010. do 2012. godine.
Studija je bila prospektivno analitičko intervenciono istraživanje
u okviru iste grupe ispitanika gde je svaki ispitanik sam sebi i
kontrola za evaluaciju efekata tretmana čime se eliminiše potreba
za balansiranjem karakteristika kao što su starost, pol, genetski
faktori itd. U studiji je bilo ukupno 70 ispitanika podeljenih u
dve grupe po starosti.Ukupan broj očiju u obe grupe iznosio je 124
oka. Kornealna topografija je rađena pre i u maksimumu dejstva
aplikovane farmakološke supstance, koristeći tangencijalnu i
aksijalnu mapu. Rezultati. Dijametar zenice u cikloplegiji bio je
veći nakon sol. Cyclopentolate 1% kod odraslih ispitanika sa tamnim
dužicama, dok je kod dece sa istim kapima veći dijametar bio kod
svetlih dužica. Promene u refrakciji a nakon sol. Atropine 1% nije
došlo kod odraslih, dok jeste kod dece (hipermetropija).
Hipermetropizacija je nastala i nakon sol. Cyclopentolate 1% i kod
odraslih i kod dece. U pogledu vrednosti simulirane keratometrije
SimK (ne u pogledu magnitude, niti osovine) nije došlo do promene u
cikloplegiji kao i u ciklokontrakciji u obe grupe ispitanika. Nalaz
na kornealnoj topografiji zadnje površine rožnjače (BFS) pokazao je
zaravnjenje rožnjače u cikloplegiji nakon dejstva sol. Atropine 1%.
Iregularnost rožnjače u centralnih 3 mm je postala manja nakon
cikloplegije sa sol.Atropine 1%. Tangencijalna mapa na kornealnoj
topografiji u cikloplegiji sa obe vrste kapi i u obe grupe
ispitanika, korišćenjem oba centra rožnjače kao referentne tačke
(fiksacionom i softverskom) bila je bez promena. Ciklokonstriktor
sol.Pilocarpine 2% dovodio je do ustrmljenja zadnje površine
rožnjače na tangencijalnoj mapi kada se fiksacioni centar koristio
kao referentna tačka. Aksijalna mapa je ostala nepromenjena u obe
grupe ispitanika i za oba centra rožnjače i u cikloplegiji i u
ciklokontrakciji. Zaključak. Može se zaključiti da se merenje
oblika rožnjače u svakodnevne dijagnostičke svrhe (određivanje
naočara, kontaktnih sočiva, kalkulacija IOL) može izvoditi i u
cikloplegiji i u toku ciklokontrakcije bez značajnog odstupanja od
rezultata istih merenja bez primene topikalnih cikloplegika ili
ciklokontraktora (u grupi rožnjača koje ne odstupaju od fizioloških
parametara oblika).
Advisors/Committee Members: Stojković, Milenko, 1966-.
Subjects/Keywords: corneal topography; cycloplegia; cyclocontraction;
corneal shape
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APA (6th Edition):
Kalezić, Tanja V., 1. (2017). Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih. (Thesis). Univerzitet u Beogradu. Retrieved from https://fedorabg.bg.ac.rs/fedora/get/o:16658/bdef:Content/get
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kalezić, Tanja V., 1977-. “Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih.” 2017. Thesis, Univerzitet u Beogradu. Accessed January 26, 2021.
https://fedorabg.bg.ac.rs/fedora/get/o:16658/bdef:Content/get.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kalezić, Tanja V., 1977-. “Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih.” 2017. Web. 26 Jan 2021.
Vancouver:
Kalezić, Tanja V. 1. Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih. [Internet] [Thesis]. Univerzitet u Beogradu; 2017. [cited 2021 Jan 26].
Available from: https://fedorabg.bg.ac.rs/fedora/get/o:16658/bdef:Content/get.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kalezić, Tanja V. 1. Efekti farmakološke cikloplegije i ciklokontrakcije na
kornealnu topografiju kod dece i odraslih. [Thesis]. Univerzitet u Beogradu; 2017. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:16658/bdef:Content/get
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales
2.
Yoon, Jeong Ho.
Modelling outcomes from orthokeratology.
Degree: Optometry & Vision Science, 2009, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/40944
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:5272/SOURCE02?view=true
► This research aimed to develop and validate a new method for calculating anterior and posterior corneal topography. The novel calculation method was then used to…
(more)
▼ This research aimed to develop and validate a new method for calculating anterior and posterior corneal topography. The novel calculation method was then used to evaluate the influence of orthokeratology (OK) lens wear and overnight edema on posterior corneal shape, and to develop a physical model for anterior and posterior corneal shape changes during myopic overnight OK.The new method uses anterior corneal topographic data derived from the Medmont E300 corneal topographer, and total corneal thickness data measured along the horizontal corneal meridian using the Holden-Payor optical pachometer. The data are then entered into an Interactive Data Language computer program, which calculates the anterior and posterior corneal apical radii of curvature and Q (asphericity) based on the calculated anterior ellipsoid curve, the locations of corneal pachometry measurements, direction of thickness measurements, and the local radius of curvature. Pachometry data were optimised based on the local radius of anterior corneal curvature and an exact solution for the relationship between real and apparent thickness. The newly developed method was validated using a range of test surfaces and repeatability was also investigated with five adult subjects.Eighteen young adult subjects wore BE OK lenses overnight only in both eyes for 14 days. Ten young adult subjects participated as a control group, wearing J-Contour RGP lenses in one eye only for one night. OK subjects were assessed on days 1, 4, 7, and 14, and control group subjects on day 1, in the morning and evening. Subjective refraction, visual acuity, corneal topography and corneal thickness were measured.Most change in refractive error occurred within the first 7 nights of overnight OK. This rapid reduction in myopia was associated with improvement in unaided VA, and flattening of anterior corneal curvature.There were no changes in posterior corneal apical radius but an increase towards an oblate posterior corneal Q was found during 14 days of overnight OK, at both morning and evening measurements.Fixed anterior corneal points were determined at 8.13mm and 5.30mm chords at morning and evening measurements in the OK group. The points of maximum increase in anterior corneal elevation at evening and morning measurements were at 6.90mm and 7.00mm chords respectively.In the OK group, significant backwards movement of anterior and posterior corneal apices was found relative to the fixed anterior corneal points at the morning measurement. Backwards movement of the anterior corneal apex remained during the day whereas the posterior corneal apex recovered to baseline.In conclusion, our results support the theory that the OK refractive effect is achieved through remodelling of anterior corneal layers, without overall corneal bending. Central corneal thinning in the evening after overnight OK lens wear is primarily due to to posterior movement in space of the anterior corneal apex. The posterior direction of overnight corneal edema across the cornea in OK lens wear is consistent with…
Subjects/Keywords: Orthokeratology; Corneal topography
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Yoon, J. H. (2009). Modelling outcomes from orthokeratology. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/40944 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:5272/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Yoon, Jeong Ho. “Modelling outcomes from orthokeratology.” 2009. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021.
http://handle.unsw.edu.au/1959.4/40944 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:5272/SOURCE02?view=true.
MLA Handbook (7th Edition):
Yoon, Jeong Ho. “Modelling outcomes from orthokeratology.” 2009. Web. 26 Jan 2021.
Vancouver:
Yoon JH. Modelling outcomes from orthokeratology. [Internet] [Doctoral dissertation]. University of New South Wales; 2009. [cited 2021 Jan 26].
Available from: http://handle.unsw.edu.au/1959.4/40944 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:5272/SOURCE02?view=true.
Council of Science Editors:
Yoon JH. Modelling outcomes from orthokeratology. [Doctoral Dissertation]. University of New South Wales; 2009. Available from: http://handle.unsw.edu.au/1959.4/40944 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:5272/SOURCE02?view=true

University of New South Wales
3.
Maseedupally, Vinod Kumar.
Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration.
Degree: Optometry & Vision Science, 2013, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/52849
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11522/SOURCE01?view=true
► The purpose of this thesis was to investigate regional corneal topographic responses in overnight orthokeratology (OK) and their influence on treatment zone (TZ) decentration. In…
(more)
▼ The purpose of this thesis was to investigate regional
corneal topographic responses in overnight orthokeratology (OK) and their influence on treatment zone (TZ) decentration. In all studies reported in this thesis
corneal topography was assessed using the Medmont E300
corneal topographer. In the initial study, eyelid photographs of healthy volunteers were captured using the Nikon D5000 digital SLR camera. Eyelid parameters were determined from the photographs using i-Metrics software. The performance of BE spherical OK lenses on minimally and moderately toric corneas was evaluated in retrospective and prospective studies. When evaluating the performance of toric OK lenses on moderately toric corneas on a small number of participants the DreamLite TRZ toric periphery OK lens design was used. In general,
corneal asymmetry was found to be significant between horizontal sectors but not in vertical sectors in minimally toric corneas. Several
corneal sectors showed a difference between East Asian and non-East Asian eyes with clinically significant differences apparent only in the superior
corneal sector. Upper eyelid curvature in non-East Asian eyes showed a stronger positive association with
corneal spherical equivalent power than in East Asian eyes. During spherical OK lens wear on minimally toric corneas, a tendency of TZ decentration to move away from the most prolate
corneal region was found. In the same cohort, it was shown that TZ decentration caused non-uniform
corneal curvature changes. Significant central temporal flattening and para-central steepening were consistent with temporal TZ decentration. When the TZ decentration during spherical OK was compared between minimally and moderately toric corneas, decentration was significantly greater in moderately toric corneas. Alternative methods of fitting OK lenses with slightly deeper sag heights did not show any benefit in controlling TZ decentration in moderately toric corneas. Toric OK lens fitting on moderately toric corneas showed greater TZ decentration compared to spherical OK lenses, but the TZ margins were well defined giving good visual outcomes. In conclusion, normal
corneal shape asymmetry in minimally toric corneas and magnitude of
corneal toricity were shown to influence TZ decentration. Toric OK lenses may provide improved visual outcomes in moderately toric corneas.
Advisors/Committee Members: Swarbrick, Helen, Optometry & Vision Science, Faculty of Science, UNSW, Gifford, Paul, Optometry & Vision Science, Faculty of Science, UNSW.
Subjects/Keywords: Treatment zone; Corneal topography; Orthokeratology; Decentration; Corneal sectors; Overnight; Corneal toricity; Asphericity; Corneal shape; Eyelid morphometry; Toric orthokeratology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Maseedupally, V. K. (2013). Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52849 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11522/SOURCE01?view=true
Chicago Manual of Style (16th Edition):
Maseedupally, Vinod Kumar. “Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration.” 2013. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021.
http://handle.unsw.edu.au/1959.4/52849 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11522/SOURCE01?view=true.
MLA Handbook (7th Edition):
Maseedupally, Vinod Kumar. “Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration.” 2013. Web. 26 Jan 2021.
Vancouver:
Maseedupally VK. Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration. [Internet] [Doctoral dissertation]. University of New South Wales; 2013. [cited 2021 Jan 26].
Available from: http://handle.unsw.edu.au/1959.4/52849 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11522/SOURCE01?view=true.
Council of Science Editors:
Maseedupally VK. Regional corneal topographic responses in overnight orthokeratology and their influence on treatment zone decentration. [Doctoral Dissertation]. University of New South Wales; 2013. Available from: http://handle.unsw.edu.au/1959.4/52849 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11522/SOURCE01?view=true

Linnaeus University
4.
Fredin, Patrik.
Correlation between Corneal Radius of Curvature and Corneal Eccentricity.
Degree: Medicine and Optometry, 2013, Linnaeus University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26486
► Aim: The primary aim of this study was to find if there is any correlation between the corneal radius of curvature and its eccentricity.…
(more)
▼ Aim: The primary aim of this study was to find if there is any correlation between the corneal radius of curvature and its eccentricity. Method: 45 subjects participated in this study, 24 emmetropes, 18 myopes and three hyperopes. All subjects were free of ocular abnormalities and had no media opacities. All the subjects had normal ocular health and good visual acuity of 1.0 or better for both distance and near. The values for eccentricity and corneal radius of curvature were obtained by using a Topcon CA-100F Corneal Analyzer. Results: For the 4.5 mm zone the only significant correlation between corneal radius of curvature and eccentricity was obtained for the mean of the meridian (p = 0.007). On the other hand, we found no significant correlation for the average of two meridians or for meridian 1 and meridian 2 separately in the 8.0 mm zone. Conclusions: We found no correlation between the corneal radius of curvature and the eccentricity for both zones. In addition, no correlation could be found between the spherical equivalent of the refractive errors and the corneal eccentricity. The reason for not finding any significant correlation between the two entities could be due to factors such as smaller sample size and poor distribution of refractive errors in the sample. Moreover, there may be other factors that could influence the overall corneal shape like eye shape, axial length and corneal diameter, which was not evaluated in this study.
Subjects/Keywords: corneal radius of curvature; corneal eccentricity; topography; conic sections; corneal shape descriptors; Medical and Health Sciences; Medicin och hälsovetenskap
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fredin, P. (2013). Correlation between Corneal Radius of Curvature and Corneal Eccentricity. (Thesis). Linnaeus University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26486
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Fredin, Patrik. “Correlation between Corneal Radius of Curvature and Corneal Eccentricity.” 2013. Thesis, Linnaeus University. Accessed January 26, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26486.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Fredin, Patrik. “Correlation between Corneal Radius of Curvature and Corneal Eccentricity.” 2013. Web. 26 Jan 2021.
Vancouver:
Fredin P. Correlation between Corneal Radius of Curvature and Corneal Eccentricity. [Internet] [Thesis]. Linnaeus University; 2013. [cited 2021 Jan 26].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26486.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Fredin P. Correlation between Corneal Radius of Curvature and Corneal Eccentricity. [Thesis]. Linnaeus University; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26486
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
5.
Jain, Deepak.
In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells.
Degree: 2020, University of Waterloo
URL: http://hdl.handle.net/10012/15905
► Fuchs endothelial dystrophy (FED), a corneal endothelium disease, is one of the leading causes for corneal transplantation. During disease progression, Descemet membrane’s (DM), the corneal…
(more)
▼ Fuchs endothelial dystrophy (FED), a corneal endothelium disease, is one of the leading causes for corneal transplantation. During disease progression, Descemet membrane’s (DM), the corneal endothelial basement membrane, biomechanical properties such as surface topography and stiffness are affected and form guttatas, pillar-like structures, with different geometries and varied stiffness. Corneal endothelial cells become apoptotic and their function is severely hampered. However, the impact of FED guttatas and stiffness on human corneal endothelial cells remains poorly understood. Currently, endothelial cell injection therapy is being developed and the effects of biomechanical cues on cell therapy is largely unknown. Hence, I hypothesized that guttatas and stiffness might affect corneal endothelial cell behavior such as increasing cell apoptosis. The impact of synthetic guttatas (s-guttata) dimensions on corneal endothelial cell behaviour in endothelial cell injection therapy conditions was studied. A significant increase in the cell apoptosis was observed across 20 µm height s-guttatas on different days. S-Guttatas with higher diameter or spacings showed significant late stage apoptosis and the increasing trend was observed in s-guttatas with lower dimensions. Furthermore, these apoptotic cells were localized around the s-guttatas; and the apoptotic population was the highest in the pattern with lower diameter and spacing. Cells surrounding s-guttatas had higher cytoskeletal stress. In addition, preliminary studies on the stiffness of DM was also performed. Cumulatively, FED guttatas have the potential to induce apoptosis.
Subjects/Keywords: cornea; Fuchs endothelial dystrophy; mechanobiology; corneal endothelial cells; surface topography
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Jain, D. (2020). In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15905
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Jain, Deepak. “In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells.” 2020. Thesis, University of Waterloo. Accessed January 26, 2021.
http://hdl.handle.net/10012/15905.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Jain, Deepak. “In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells.” 2020. Web. 26 Jan 2021.
Vancouver:
Jain D. In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10012/15905.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Jain D. In vitro model for Fuchs Endothelial Dystrophy and its effects on corneal endothelial cells. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/15905
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Bradford
6.
Parkinson, Annette.
Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population.
Degree: PhD, 2012, University of Bradford
URL: http://hdl.handle.net/10454/6328
► Aim: This study looks at the effect of orthokeratology on a number of biometric parameters and refractive error in an adult population. Method: Forty three…
(more)
▼ Aim: This study looks at the effect of orthokeratology on a number of biometric parameters and refractive error in an adult population. Method: Forty three myopic subjects were recruited to a twelve month study into the effects of orthokeratology on ocular biometry and refractive error. Two different back surface lens designs were applied right eye) pentacurve and left eye) aspheric. The aspheric design was chosen to more closely mimic the cornea's natural shape. Anterior and posterior apical radii and p-values; corneal thickness and anterior chamber depth were measured using the Orbscan IIz; together with ocular biometry by IOL Master and a standard clinical refraction. All measurements were repeated at one night, one week, one, three, six and twelve months. Refractive changes were analysed against biometric changes. Results: Twenty seven participants completed one month of lens wear. Twelve subjects completed twelve months of lens wear. Subjects with myopia ≤ -4.00DS were successfully treated with orthokeratology. Both anterior and posterior apical radii and p values were altered by orthokeratology. Corneal thickness changes were in agreement with previously published studies. Axial length and anterior chamber depth were unaffected by the treatment. Conclusion: Orthokeratology should be available as an alternative to laser refractive surgery. It is best restricted to myopes of up to -4.00DS with low levels of with the rule corneal astigmatism. The use of an aspheric back design contact lens did not produce a significant benefit over that of a pentacurve.
Subjects/Keywords: 617.7; Orthokeratology; Ocular biometry; Corneal topography; Refractive error
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Parkinson, A. (2012). Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population. (Doctoral Dissertation). University of Bradford. Retrieved from http://hdl.handle.net/10454/6328
Chicago Manual of Style (16th Edition):
Parkinson, Annette. “Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population.” 2012. Doctoral Dissertation, University of Bradford. Accessed January 26, 2021.
http://hdl.handle.net/10454/6328.
MLA Handbook (7th Edition):
Parkinson, Annette. “Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population.” 2012. Web. 26 Jan 2021.
Vancouver:
Parkinson A. Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population. [Internet] [Doctoral dissertation]. University of Bradford; 2012. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10454/6328.
Council of Science Editors:
Parkinson A. Ocular biometric change in orthokeratology : an investigation into the effects of orthokeratology on ocular biometry and refractive error in an adult population. [Doctoral Dissertation]. University of Bradford; 2012. Available from: http://hdl.handle.net/10454/6328
7.
Motta, Lorenzo.
Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale.
Degree: 2012, Università degli Studi di Catania
URL: http://hdl.handle.net/10761/1006
► ABSTRACT Obiettivo. Confronto dei risultati visivi e topografici in pazienti con cheratocono in evoluzione, sottoposti a cross-linking corneale (CCL) con procedura epi-off ed epi-on. Materiali…
(more)
▼ ABSTRACT
Obiettivo. Confronto dei risultati visivi e topografici in pazienti con cheratocono in evoluzione, sottoposti a cross-linking corneale (CCL) con procedura epi-off ed epi-on.
Materiali e metodi. 72 pazienti; 36 tecnica standard e 36 tecnica transepiteliale, da gennaio 2010 a luglio 2011. Pachimetria > 400 ìm. Follow-up dopo trattamento (1,3 e 6 mesi) eseguito con: visus naturale e corretto, refrazione, biomicroscopia alla lampada a fessura, topografia corneale.
Risultati. 36 trattati con CCL standard dopo 6 mesi si dimostra riduzione del Kmax di 2 D e aumento visus di 3/10. Complicanze: 4 casi haze transitorio a 2 mesi risolto con steroidi topici. 36 con CCL transepiteliale, incremento visus di 5/10 e riduzione Kmax di 4 D e no complicanze significative.
Conclusioni.CCL transepiteliale migliore di quello standard (riduzione Kmax e aumento visus). Considerando l assenza di complicanze postoperatorie, meglio adoperare il CCL epi-on in questi casi.
Subjects/Keywords: Area 06 - Scienze mediche; corneal cross-linking, keratoconus, topography
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MLA ·
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APA (6th Edition):
Motta, L. (2012). Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale. (Thesis). Università degli Studi di Catania. Retrieved from http://hdl.handle.net/10761/1006
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Motta, Lorenzo. “Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale.” 2012. Thesis, Università degli Studi di Catania. Accessed January 26, 2021.
http://hdl.handle.net/10761/1006.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Motta, Lorenzo. “Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale.” 2012. Web. 26 Jan 2021.
Vancouver:
Motta L. Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale. [Internet] [Thesis]. Università degli Studi di Catania; 2012. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10761/1006.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Motta L. Confronto dei risultati visivi e topografici in pazienti con cheratocono sottoposti a cross-linking corneale: tecnica tradizionale Vs transepiteliale. [Thesis]. Università degli Studi di Catania; 2012. Available from: http://hdl.handle.net/10761/1006
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
8.
Lu, Fenghe.
BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY.
Degree: 2006, University of Waterloo
URL: http://hdl.handle.net/10012/2961
► Purpose: Although orthokeratology (non-surgical corneal reshaping, Corneal Refractive Therapy, CRT®) has been used for almost a half century, contemporary CRT's outcomes and mechanisms still require…
(more)
▼ Purpose: Although orthokeratology (non-surgical corneal reshaping, Corneal Refractive Therapy, CRT®) has been used for almost a half century, contemporary CRT's outcomes and mechanisms still require investigation. A series of studies was designed to examine different aspects of non-surgical corneal reshaping for myopic and hyperopic corrections, including the efficacy and stability of this procedure, the effect of the lens material characteristics (Dk/t), and the corneal or superficial structural change (e. g. corneal/epithelial thickness) in corneal reshaping. Methods: In the CRT® for myopia (CRT1) study, 20 myopes wore CRT® lenses on one eye and control lenses on the contralateral eye (eye randomized) for one night while sleeping. Corneal topography and refractive error were measured the night prior to lens insertion, immediately after lens removal on the following morning and at 20 and 60 minutes and 3, 6 and 12 hours later. In the CRT® for hyperopia (CRTH) study, 20 ametropes wore CRT®H lenses on one eye for one night while sleeping, the contralateral eye (no lens wear) served as control (eye randomized). Corneal topography, aberrations and refractive error were measured the night prior to lens insertion, immediately after lens removal on the following morning and at 1 and 3, 6, 12 and 28 hours later. In the relatively long term (4 weeks) CRT® for myopia (CRT2) study, 23 myopes wore CRT® lenses overnight and removed their lenses on awakening. Visual Acuity (VA), subjective vision, refractive error, aberrations, and corneal topography were measured at baseline, immediately after lens removal on the first day and 14 hours later, and these measurements were repeated on days 4, 10, and 28. The treatment zone size was demarcated by the change in corneal curvature from negative to positive and vice versa, using tangential difference maps from the corneal topographer. In the study of effects of Dk/t on CRT® for myopia (CRTHDK), 20 myopic subjects were fit with Menicon Z (MZ) lenses (Dk/t=90. 6, Paragon CRT®) on one eye and an Equalens II (EII) CRT® lenses (Dk/t=47. 2) on the contralateral eye (eye randomized). Corneal topography, refractive error and aberrations were measured before lens insertion (baseline), and the following day after overnight lens wear, on lens removal and 1, 3, 6, 12 hours later. In the study of short term effects of CRT® for myopia and hyperopia (STOK), 20 ametropes wore CRT® and CRT®H lenses in a random order on one eye (randomly selected). The lenses were worn for 15, 30 and 60 minutes (randomly ordered, with each period taking place on a different day). Refractive error, aberrations, corneal topography, and corneal/epithelial thickness (using OCT) were measured before and after lens wear. The measurements were performed on the control eyes at 60 minutes only. Results: In the CRT1 study, after one night of CRT® for myopia, the central cornea flattened and the mid-periphery steepened, and…
Subjects/Keywords: Optometry & Ophthalmology; Corneal Refractive Therapy; Corneal Topography; Aberration; Corneal Thickness; Epithelial Thickness; Efficacy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lu, F. (2006). BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/2961
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lu, Fenghe. “BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY.” 2006. Thesis, University of Waterloo. Accessed January 26, 2021.
http://hdl.handle.net/10012/2961.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lu, Fenghe. “BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY.” 2006. Web. 26 Jan 2021.
Vancouver:
Lu F. BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY. [Internet] [Thesis]. University of Waterloo; 2006. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10012/2961.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lu F. BIOMECHANICAL ALTERATION OF CORNEAL MORPHOLOGY
AFTER CORNEAL REFRACTIVE THERAPY. [Thesis]. University of Waterloo; 2006. Available from: http://hdl.handle.net/10012/2961
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology
9.
Tyagi, Garima.
Ocular surface changes with short-term contact lens wear.
Degree: 2011, Queensland University of Technology
URL: https://eprints.qut.edu.au/49758/
► Contact lenses are a common method for the correction of refractive errors of the eye. While there have been significant advancements in contact lens designs…
(more)
▼ Contact lenses are a common method for the correction of refractive errors of the eye. While there have been significant advancements in contact lens designs and materials over the past few decades, the lenses still represent a foreign object in the ocular environment and may lead to physiological as well as mechanical effects on the eye. When contact lenses are placed in the eye, the ocular anatomical structures behind and in front of the lenses are directly affected. This thesis presents a series of experiments that investigate the mechanical and physiological effects of the short-term use of contact lenses on anterior and posterior corneal topography, corneal thickness, the eyelids, tarsal conjunctiva and tear film surface quality.
The experimental paradigm used in these studies was a repeated measures, cross-over study design where subjects wore various types of contact lenses on different days and the lenses were varied in one or more key parameters (e.g. material or design). Both, old and newer lens materials were investigated, soft and rigid lenses were used, high and low oxygen permeability materials were tested, toric and spherical lens designs were examined, high and low powers and small and large diameter lenses were used in the studies. To establish the natural variability in the ocular measurements used in the studies, each experiment also contained at least one “baseline” day where an identical measurement protocol was followed, with no contact lenses worn. In this way, changes associated with contact lens wear were considered in relation to those changes that occurred naturally during the 8 hour period of the experiment.
In the first study, the regional distribution and magnitude of change in corneal thickness and topography was investigated in the anterior and posterior cornea after short-term use of soft contact lenses in 12 young adults using the Pentacam. Four different types of contact lenses (Silicone hydrogel/ Spherical/–3D, Silicone Hydrogel/Spherical/–7D, Silicone Hydrogel/Toric/–3D and HEMA/Toric/–3D) of different materials, designs and powers were worn for 8 hours each, on 4 different days. The natural diurnal changes in corneal thickness and curvature were measured on two separate days before any contact lens wear. Significant diurnal changes in corneal thickness and curvature within the duration of the study were observed and these were taken into consideration for calculating the contact lens induced corneal changes. Corneal thickness changed significantly with lens wear and the greatest corneal swelling was seen with the hydrogel (HEMA) toric lens with a noticeable regional swelling of the cornea beneath the stabilization zones, the thickest regions of the lenses. The anterior corneal surface generally showed a slight flattening with lens wear. All contact lenses resulted in central posterior corneal steepening, which correlated with the relative degree of corneal swelling. The corneal swelling induced by the silicone hydrogel contact lenses was typically less than the natural diurnal…
Subjects/Keywords: contact lens, cornea, corneal topography, corneal thickness, corneal swelling, Pentacam, Medmont, videokeratoscope, eyelids, blepharoptosis, lid-wiper epitheliopathy, tarsal conjunctiva, tear film, tear film surface quality, non-invasive; high-speed videokeratoscopy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tyagi, G. (2011). Ocular surface changes with short-term contact lens wear. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/49758/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tyagi, Garima. “Ocular surface changes with short-term contact lens wear.” 2011. Thesis, Queensland University of Technology. Accessed January 26, 2021.
https://eprints.qut.edu.au/49758/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tyagi, Garima. “Ocular surface changes with short-term contact lens wear.” 2011. Web. 26 Jan 2021.
Vancouver:
Tyagi G. Ocular surface changes with short-term contact lens wear. [Internet] [Thesis]. Queensland University of Technology; 2011. [cited 2021 Jan 26].
Available from: https://eprints.qut.edu.au/49758/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tyagi G. Ocular surface changes with short-term contact lens wear. [Thesis]. Queensland University of Technology; 2011. Available from: https://eprints.qut.edu.au/49758/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Rio Grande do Sul
10.
Rosa, André Luís Beling da.
An accessible approach for corneal topography.
Degree: 2013, Universidade do Rio Grande do Sul
URL: http://hdl.handle.net/10183/95987
► Corneal topography consists of measuring the corneal shape, which is a key factor for visual acuity. The exam is used, for instance, in keratoconus detection,…
(more)
▼ Corneal topography consists of measuring the corneal shape, which is a key factor for visual acuity. The exam is used, for instance, in keratoconus detection, personalized contact lens fitting, in pre- and post-procedures associated with refractive surgery and corneal transplants. This thesis presents an accessible, inexpensive and portable approach to perform corneal topographies. The results obtained with our prototype show a mean difference of about 0.02 millimeters, equivalent to 0.5% of the mean corneal radius, when compared to topographies acquired with a commercial device. Our approach is based on Placido’s disks, a set of concentric disks that are placed in front of the patient’s eye and reflected on the cornea. Observing the deformation of the projected pattern, one can identify some refractive conditions (e.g., astigmatism, keratoconus) and estimate the patient’s corneal topography. We have built a clip-on device to be used with a cell phone to emit the patterns, which are then captured by the cell phone camera. We use a software pipeline to enhance the images, segment the patterns, associate the emitted pattern with the captured one to sample the signal, and finally estimate the corneal surface. The estimated shape is then decomposed using Zernike polynomials in components with specific optical meanings. We have evaluated the results obtained with our prototype in three ways: visual inspection of keratoscopies, keratoconus detection, and comparison with the results produced by a commercial corneal topographer. According to such analysis, our device can be used for screening of individuals with keratoconus, and to obtain corneal topographies with 0.02-millimeter differences with respect to the results obtained with a commercial corneal topographer.
Topografias da córnea consistem em medir a forma da córnea, que é um fator chave para a acuidade visual. O exame é usado, por exemplo, na detecção de ceratocone, ajuste personalizado de lentes de contato, e pre e pós procedimentos associados com cirurgias refrativas e transplante de córnea. Esta dissertação apresenta, uma abordagem acessível e portátil para realizar topografias da córnea. Os resultados obtidos com o nosso protótipo mostram uma diferença média por volta de 0.02 milimetros, equivalente a 0.5% do raio médio da córnea, quando comparadas com topografias adquiridas com um topografo comercial. Nossa abordagem é baseada no disco de Plácido, a um conjunto de círculos concêntricos que são colocados na frente do olho do paciente e refletidos na córnea. Observando a deformação do padrão projetado, podemos identificar algumas condições refrativas (e.g. astigmatismo, ceratocone) e estimar a topografia da córnea do paciente. Nós construimos um dispositivo para ser utilizado com um celular para emitir os padrões, estes são então capturados pela câmera do celular. Nós usamos um sequência de procedimentos para melhor as imagens, segmentar os padrões, associar o padrão capturado com o emitido para amostrar o sinal, e finalmente estimar a superfície da córnea. A…
Advisors/Committee Members: Oliveira Neto, Manuel Menezes de.
Subjects/Keywords: Computação gráfica; Corneal topography; Image processing; Topografia; Processamento : Imagem; Zernike polynomials; Geometric reconstruction
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rosa, A. L. B. d. (2013). An accessible approach for corneal topography. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/95987
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rosa, André Luís Beling da. “An accessible approach for corneal topography.” 2013. Thesis, Universidade do Rio Grande do Sul. Accessed January 26, 2021.
http://hdl.handle.net/10183/95987.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rosa, André Luís Beling da. “An accessible approach for corneal topography.” 2013. Web. 26 Jan 2021.
Vancouver:
Rosa ALBd. An accessible approach for corneal topography. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2013. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10183/95987.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rosa ALBd. An accessible approach for corneal topography. [Thesis]. Universidade do Rio Grande do Sul; 2013. Available from: http://hdl.handle.net/10183/95987
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona
11.
Solem, Cameron Cole.
Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
.
Degree: 2017, University of Arizona
URL: http://hdl.handle.net/10150/624129
► The visual quality effects from the dynamic behavior of the tear film have been determined through measurements acquired with a high resolution Twyman-Green interferometer. The…
(more)
▼ The visual quality effects from the dynamic behavior of the tear film have been determined through measurements acquired with a high resolution Twyman-Green interferometer. The base shape of the eye has been removed to isolate the aberrations induced by the tear film. The measured tear film was then combined with a typical human eye model to simulate visual performance. Fourier theory has been implemented to calculate the incoherent point spread function, the modulation transfer function, and the subjective quality factor for this system. Analysis software has been developed for ease of automation for large data sets, and outputs movies have been made that display these visual quality metrics alongside the tear film. Post processing software was written to identify and eliminate bad frames. As a whole, this software creates the potential for increased intuition about the connection between blinks, tear film dynamics and visual quality.
Advisors/Committee Members: Greivenkamp, John (advisor), Greivenkamp, John (committeemember), Schwiegerling, Jim (committeemember), Liang, Rongguang (committeemember).
Subjects/Keywords: dynamic corneal topography;
Human eye;
Optical;
Optics;
Tear Film;
Visual quality metrics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Solem, C. C. (2017). Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
. (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/624129
Chicago Manual of Style (16th Edition):
Solem, Cameron Cole. “Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
.” 2017. Masters Thesis, University of Arizona. Accessed January 26, 2021.
http://hdl.handle.net/10150/624129.
MLA Handbook (7th Edition):
Solem, Cameron Cole. “Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
.” 2017. Web. 26 Jan 2021.
Vancouver:
Solem CC. Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
. [Internet] [Masters thesis]. University of Arizona; 2017. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10150/624129.
Council of Science Editors:
Solem CC. Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography
. [Masters Thesis]. University of Arizona; 2017. Available from: http://hdl.handle.net/10150/624129

University of Arizona
12.
Micali, Jason Daniel.
Interferometer for Measuring Dynamic Corneal Topography
.
Degree: 2015, University of Arizona
URL: http://hdl.handle.net/10150/581129
► The cornea is the anterior most surface of the eye and plays a critical role in vision. A thin fluid layer, the tear film, coats…
(more)
▼ The cornea is the anterior most surface of the eye and plays a critical role in vision. A thin fluid layer, the tear film, coats the outer surface of the cornea and serves to protect, nourish, and lubricate the cornea. At the same time, the tear film is responsible for creating a smooth continuous surface where the majority of refraction takes place in the eye. A significant component of vision quality is determined by the shape of the cornea and stability of the tear film. It is desirable to possess an instrument that can measure the
corneal shape and tear film surface with the same accuracy and resolution that is currently performed on common optical elements. A dual interferometer system for measuring the dynamic
corneal topography is designed, built, and verified. The completed system is validated by testing on human subjects. The system consists of two co-aligned polarization splitting Twyman-Green interferometers designed to measure phase instantaneously. The primary interferometer measures the surface of the tear film while the secondary interferometer simultaneously tracks the absolute position of the cornea. Eye motion, ocular variation, and a dynamic tear film surface will result in a non-null configuration of the surface with respect to the interferometer system. A non-null test results in significant interferometer induced errors that add to the measured phase. New algorithms are developed to recover the absolute surface
topography of the tear film and
corneal surface from the simultaneous interferometer measurements. The results are high-resolution and high-accuracy surface
topography measurements of the in vivo cornea that are captured at standard camera frame rates. This dissertation will cover the development and construction of an interferometer system for measuring the dynamic
corneal topography of the human eye. The discussion starts with the completion of an interferometer for measuring the tear film. The tear film interferometer is part of an ongoing research project that has spanned multiple dissertations. For this research, the instrument was tested on human subjects and resulted in refinements to the interferometer design. The final configuration of the tear film interferometer and results from human subjects testing are presented. Feedback from this instrument was used to support the development and construction of the interferometric
corneal topographer system. A calibration is performed on the instrument, and then verified against simulated eye surfaces. Finally, the instrument is validated by testing on human subjects. The result is an interferometer system that can non-invasively measure the dynamic
corneal topography with greater accuracy and resolution than existing technologies.
Advisors/Committee Members: Greivenkamp, John E (advisor), Greivenkamp, John E. (committeemember), Schwiegerling, James T. (committeemember), Wyant, James C. (committeemember).
Subjects/Keywords: Corneal Topography;
Dynamic surface measurements;
Interferometry;
Metrology;
Tear Film;
Optical Sciences;
Contact lenses
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Micali, J. D. (2015). Interferometer for Measuring Dynamic Corneal Topography
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/581129
Chicago Manual of Style (16th Edition):
Micali, Jason Daniel. “Interferometer for Measuring Dynamic Corneal Topography
.” 2015. Doctoral Dissertation, University of Arizona. Accessed January 26, 2021.
http://hdl.handle.net/10150/581129.
MLA Handbook (7th Edition):
Micali, Jason Daniel. “Interferometer for Measuring Dynamic Corneal Topography
.” 2015. Web. 26 Jan 2021.
Vancouver:
Micali JD. Interferometer for Measuring Dynamic Corneal Topography
. [Internet] [Doctoral dissertation]. University of Arizona; 2015. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10150/581129.
Council of Science Editors:
Micali JD. Interferometer for Measuring Dynamic Corneal Topography
. [Doctoral Dissertation]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/581129

University of Arizona
13.
Primeau, Brian Christopher.
INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
.
Degree: 2011, University of Arizona
URL: http://hdl.handle.net/10150/202971
► The anterior refracting surface of the eye is the thin tear film that forms on the surface of the cornea. When a contact lens is…
(more)
▼ The anterior refracting surface of the eye is the thin tear film that forms on the surface of the cornea. When a contact lens is on worn, the tear film covers the contact lens as it would a bare cornea, and is affected by the contact lens material properties. Tear film irregularity can cause both discomfort and vision quality degradation. Under normal conditions, the tear film is less than 10 microns thick and the thickness and
topography change in the time between blinks. In order to both better understand the tear film, and to characterize how contact lenses affect tear film behavior, two interferometers were designed and built to separately measure tear film behavior in vitro and in vivo. An in vitro method of characterizing dynamic fluid layers applied to contact lenses mounted on mechanical substrates has been developed using a phase-shifting Twyman- Green interferometer. This interferometer continuously measures light reflected from the surface of the fluid layer, allowing precision analysis of the dynamic fluid layer. Movies showing this fluid layer behavior can be generated. The fluid behavior on the contact lens surface is measured, allowing quantitative analysis beyond what typical contact angle or visual inspection methods provide. The in vivo interferometer is a similar system, with additional modules included to provide capability for human testing. This tear film measurement allows analysis beyond capabilities of typical fluorescein visual inspection or videokeratometry and provides better sensitivity and resolution than shearing interferometry methods. The in vitro interferometer system has measured the formation and break up of fluid layers. Different fluid and contact lens material combinations have been used, and significant fluid layer properties have been observed in some cases. This dissertation discusses the design of this interferometer along with analysis methods used. Example measurement results of different contact lens are presented highlighting the capabilities of the instrument. This dissertation also provides the in vivo interferometer design, along with the considerations that must be taken when designing an interferometer for on-eye diagnostics. Discussions include accommodating eye movement, design of null optics for a range of ocular geometries, and laser emission limits for on-eye interferometry in general.
Advisors/Committee Members: Greivenkamp, John E (advisor), Schwiegerling, James (committeemember), Liang, Rongguang (committeemember), Greivenkamp, John E. (committeemember).
Subjects/Keywords: Interferometry;
Metrology;
Optical systems;
Tear film;
Optical Sciences;
Contact Lens;
Corneal topography
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Primeau, B. C. (2011). INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/202971
Chicago Manual of Style (16th Edition):
Primeau, Brian Christopher. “INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
.” 2011. Doctoral Dissertation, University of Arizona. Accessed January 26, 2021.
http://hdl.handle.net/10150/202971.
MLA Handbook (7th Edition):
Primeau, Brian Christopher. “INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
.” 2011. Web. 26 Jan 2021.
Vancouver:
Primeau BC. INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
. [Internet] [Doctoral dissertation]. University of Arizona; 2011. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10150/202971.
Council of Science Editors:
Primeau BC. INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS
. [Doctoral Dissertation]. University of Arizona; 2011. Available from: http://hdl.handle.net/10150/202971

University of New South Wales
14.
Keshavarzi, Kaykhosrow.
Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern.
Degree: Science. Optometry and Vision Science, 2002, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/67833
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68680/SOURCE01?view=true
Subjects/Keywords: Corneal topography; Algorithms; Thesis Digitisation Program
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Chicago ·
MLA ·
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APA (6th Edition):
Keshavarzi, K. (2002). Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/67833 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68680/SOURCE01?view=true
Chicago Manual of Style (16th Edition):
Keshavarzi, Kaykhosrow. “Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern.” 2002. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021.
http://handle.unsw.edu.au/1959.4/67833 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68680/SOURCE01?view=true.
MLA Handbook (7th Edition):
Keshavarzi, Kaykhosrow. “Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern.” 2002. Web. 26 Jan 2021.
Vancouver:
Keshavarzi K. Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern. [Internet] [Doctoral dissertation]. University of New South Wales; 2002. [cited 2021 Jan 26].
Available from: http://handle.unsw.edu.au/1959.4/67833 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68680/SOURCE01?view=true.
Council of Science Editors:
Keshavarzi K. Algorithms for improving accuracy and validity of corneal topographical measurements and photokeratoscopy with new target pattern. [Doctoral Dissertation]. University of New South Wales; 2002. Available from: http://handle.unsw.edu.au/1959.4/67833 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68680/SOURCE01?view=true
15.
Mendes, Marcio Henrique.
Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito.
Degree: PhD, Oftalmologia, 2013, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/
;
► OBJETIVOS: Comparar os valores da pressão intraocular (PIO), obtidos por intermédio do tonômetro de Perkins (TPK), tonômetro de contorno dinâmico Pascal (TCD) e Tono-Pen (TNP),…
(more)
▼ OBJETIVOS: Comparar os valores da pressão intraocular (PIO), obtidos por intermédio do tonômetro de Perkins (TPK), tonômetro de contorno dinâmico Pascal (TCD) e Tono-Pen (TNP), confrontando-os com o tonômetro de aplanação de Goldmann (TAG), e correlacionar seus valores tonométricos com parâmetros biométricos oculares em pacientes portadores de glaucoma congênito primário. MÉTODOS: Estudo prospectivo, transversal, com inclusão de 46 pacientes (46 olhos) com diagnóstico de glaucoma congênito primário, com idades entre 12 e 40 anos, após obtenção do Termo de Consentimento Livre e Esclarecido. Todos os olhos estudados foram submetidos à tonometria ocular usando os tonômetros de Goldmann, de Perkins, o Tono-Pen e o tonômetro de contorno dinâmico Pascal. A ordem das tonometrias foi aleatória e o tonômetro de Goldmann foi adotado como padrão ouro. Os parâmetros biométricos estudados foram a curvatura (medida pela ceratometria), a espessura central da córnea (paquimetria), o diâmetro
corneal (medido por meio de compasso cirúrgico) e o comprimento axial do olho foi obtido pela biometria ultrassônica. As distribuições dos parâmetros biométricos, assim como das tonometrias foram plotadas e analisadas conforme teste de Kolmogorov-Smirnov para aceitação de normalidade. O teste t de Student pareado para amostras independentes foi empregado para comparar as médias tonométricas de cada tonômetro com o padrão ouro. As correlações entre os parâmetros biométricos e as tonometrias foram realizadas através do coeficiente de correlação de Pearson e gráficos de regressão linear. O mesmo procedimento foi feito entre os parâmetros biométricos e as diferenças entre as três distintas tonometrias e a TAG. A concordância entre os tonômetros Perkins, Pascal e Tono-Pen e o de Goldamnn foi realizada pelo teste de concordância de correlação (CCC) e graficamente pelo método de Bland-Altman. O valor de corte de 2 mmHg foi adotado para avaliar a empregabilidade clínica desses tonômetros em pacientes semelhantes aos da amostra. RESULTADOS: O teste de Kolmogorov-Smirnov indicou aceitação da normalidade para todas as distribuições estudadas (TAG, TPK, TCD, TNP, Diâmetros
corneal e axial, ceratometria média e paquimetria). Os momentos de correlação de Pearson empregados para realizar estudo das correlações entre os parâmetros biométricos e cada tonometria foram estatisticamente não significativos. As correlações entre os parâmetros biométricos e as diferenças entre tonometrias em relação ao TAG não apresentaram significância em sua maioria, sendo a única exceção a correlação moderada entre a diferença do TAG e o Tono-Pen versus a ceratometria média. No entanto, o coeficiente de determinação evidenciou influência modesta da ceratometria nessas diferenças (r² = 0,16; p = 0,004). O teste t de Student pareado demonstrou diferença significativa entre o TAG e o TP (p < 0,001). A diferença não foi significativa entre o TAG e o Pascal (p = 0.30), ou entre o TAG e o Tono-Pen (p = 0.68). Houve excelente concordância entre o TAG e o TP (CCC = 0,98; intervalo de…
Advisors/Committee Members: Betinjane, Alberto Jorge.
Subjects/Keywords: Biometria; Biometry; Corneal pachymetry; Corneal topography; Estudos prospectivos; Glaucoma/congenital; Glaucoma/congênito; Intraocular pressure; Paquimetria corneana; Pressão intraocular; Prospectives studies; Tonometria ocular; Tonometry ocular; Topografia da córnea
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mendes, M. H. (2013). Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/ ;
Chicago Manual of Style (16th Edition):
Mendes, Marcio Henrique. “Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito.” 2013. Doctoral Dissertation, University of São Paulo. Accessed January 26, 2021.
http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/ ;.
MLA Handbook (7th Edition):
Mendes, Marcio Henrique. “Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito.” 2013. Web. 26 Jan 2021.
Vancouver:
Mendes MH. Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito. [Internet] [Doctoral dissertation]. University of São Paulo; 2013. [cited 2021 Jan 26].
Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/ ;.
Council of Science Editors:
Mendes MH. Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito. [Doctoral Dissertation]. University of São Paulo; 2013. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/ ;

Queensland University of Technology
16.
Tang, Wilfrid.
The relationship between corneal topography and visual performance.
Degree: 2001, Queensland University of Technology
URL: http://eprints.qut.edu.au/36759/
Subjects/Keywords: Corneal topography; Visual perception; Computer-assisted videokeratography; thesis; doctoral
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tang, W. (2001). The relationship between corneal topography and visual performance. (Thesis). Queensland University of Technology. Retrieved from http://eprints.qut.edu.au/36759/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tang, Wilfrid. “The relationship between corneal topography and visual performance.” 2001. Thesis, Queensland University of Technology. Accessed January 26, 2021.
http://eprints.qut.edu.au/36759/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tang, Wilfrid. “The relationship between corneal topography and visual performance.” 2001. Web. 26 Jan 2021.
Vancouver:
Tang W. The relationship between corneal topography and visual performance. [Internet] [Thesis]. Queensland University of Technology; 2001. [cited 2021 Jan 26].
Available from: http://eprints.qut.edu.au/36759/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tang W. The relationship between corneal topography and visual performance. [Thesis]. Queensland University of Technology; 2001. Available from: http://eprints.qut.edu.au/36759/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology
17.
Buehren, Tobias F.
Corneal topography, near work and eyelid forces.
Degree: 2003, Queensland University of Technology
URL: https://eprints.qut.edu.au/15882/
► The cornea is the most powerful refractive component of the eye and as such, subtle changes in corneal shape can cause substantial changes in the…
(more)
▼ The cornea is the most powerful refractive component of the eye and as such, subtle changes in corneal shape can cause substantial changes in the optical characteristics of the eye. Monocular diplopia has previously been linked to corneal distortion following near work in various studies but has not been investigated in detail. The work reported in this thesis has investigated the optical effects of corneal distortions caused by eyelid forces and demonstrated that several corneal higher and lower order Zernike wavefront aberrations can change following reading.
Measuring subtle changes in corneal topography requires the highest possible instrument accuracy, while software analysis tools should be able to detect and highlight those subtle changes with high reliability. The effect of ocular microfluctuations on the qualitative and quantitative analysis of corneal topography was investigated. A technique was developed to measure tilt, displacement, and cyclotorsion in multiple videokeratographs from the same cornea. This information was used to reposition each videokeratograph according to the average position of a sample of multiple measurements. The corneal topography of ten subjects was measured 20 times each, using videokeratoscopy. The RMSE calculated from difference between single videokeratographs and the average videokeratograph decreased by an average of 24.6 % for the ten subjects' data. The method can improve the precision performance of videokeratoscopy in multiple measurements of corneal topography.
A study was undertaken, to investigate whether there are significant changes in corneal topography during accommodation in normal corneas and corneas that are pathologically thinner due to keratoconus. This was done to eliminate the possibility that changes in corneal aberrations associated with near work could be at least partly due to corneal changes caused by the effects of accommodation. A videokeratoscope was modified to present an accommodation stimulus that was coaxial with the instrument's measurement axis. Six subjects with normal corneas and four subjects with keratoconus were studied. In the initial analysis it was found that a number of the subjects showed significant changes in corneal topography as accommodation changed. However further analysis showed a significant group mean excyclotorsion of the topography maps for both accommodation stimuli compared with the 0 D stimulus. When the excyclotorsion was accounted for, no clear evidence of statistically significant changes in corneal topography as a result of accommodation were found. A small ocular excyclotorsion typically accompanies accommodation and this changes the relative orientation of the topography of the cornea.
To investigate the effects of eyelid pressure on corneal shape and corneal aberrations during reading, twenty young subjects with normal ocular health were recruited. Cornea1 topography of one eye was measured with a videokeratoscope prior to reading and then again after a 60 minute reading task. Twelve of…
Subjects/Keywords: Videokeratoscope; Cornea; Corneal topography; reading; lid forces; aberrations
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Buehren, T. F. (2003). Corneal topography, near work and eyelid forces. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/15882/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Buehren, Tobias F. “Corneal topography, near work and eyelid forces.” 2003. Thesis, Queensland University of Technology. Accessed January 26, 2021.
https://eprints.qut.edu.au/15882/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Buehren, Tobias F. “Corneal topography, near work and eyelid forces.” 2003. Web. 26 Jan 2021.
Vancouver:
Buehren TF. Corneal topography, near work and eyelid forces. [Internet] [Thesis]. Queensland University of Technology; 2003. [cited 2021 Jan 26].
Available from: https://eprints.qut.edu.au/15882/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Buehren TF. Corneal topography, near work and eyelid forces. [Thesis]. Queensland University of Technology; 2003. Available from: https://eprints.qut.edu.au/15882/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology
18.
Zhu, Mingxia.
Microfluctuations of Wavefront Aberrations of the Eye.
Degree: 2005, Queensland University of Technology
URL: https://eprints.qut.edu.au/16121/
► The human eye suffers various optical aberrations that degrade the retinal image. These aberrations include defocus and astigmatism, as well as the higher order aberrations…
(more)
▼ The human eye suffers various optical aberrations that degrade the retinal image. These aberrations include defocus and astigmatism, as well as the higher order aberrations that also play an important role in our vision. The optics of the eye are not static, but are continuously fluctuating. The work reported in this thesis has studied the nature of the microfluctuations of the wavefront aberrations of the eye and has investigated factors that influence the microfluctuations.
The fluctuations in the ocular surface of the eye were investigated using high speed videokeratoscopy which measures the dynamics of the ocular surface topography. Ocular surface height difference maps were computed to illustrate the changes in the tear film in the inter-blink interval. The videokeratoscopy data was used to derive the ocular surface wavefront aberrations up to the 4th radial order of the Zernike polynomial expension. We examined the ocular surface dynamics and temporal changes in the ocular surface wavefront aberrations in the inter-blink interval. During the first 0.5 sec following a blink, the tear thickness at the upper edge of the topography map appeared to thicken by about 2 microns. The influence of pulse and instantaneous pulse rate on the microfluctuations in the corneal wavefront aberrations was also investigated. The fluctuations in ocular surface wavefront aberrations were found to be uncorrelated with the pulse and instantaneous heart rates. In the clinical measurement of the ocular surface topography using videokeratoscopy, capturing images 2 to 3 seconds after a blink will result in more consistent results.
To investigate fluctuations in the wavefront aberrations of the eye and their relation to pulse and respiration frequencies we used a wavefront sensor to measure the dynamics of the aberrations up to the Zernike polynomial 4th radial order. Simultaneously, the subject's pulse rate was measured, from which the instantaneous heart rate was derived. An auto-regressive process was used to derive the power spectra of the Zernike aberration signals, as well as pulse and instantaneous heart rate signals. Linear regression analysis was performed between the frequency components of Zernike aberrations and the pulse and instantaneous heart rate frequencies. Cross spectrum density and coherence analyses were also applied to investigate the relation between fluctuations of wavefront aberrations and pulse and instantaneous heart rate. The correlations between fluctuations of individual Zernike aberrations were also determined. A frequency component of all Zernike aberrations up to the 4th radial order was found to be significantly correlated with the pulse frequency (all > 2R0.51, p<0.02), and a frequency component of 9 out of 12 Zernike aberrations was also significantly correlated with instantaneous heart rate frequency (all>2R0.46, p<0.05). The major correlations among Zernike aberrations occurred between second order and fourth order aberrations with the same angular frequencies. Higher order…
Subjects/Keywords: corneal topography; ocular aberrations; wavefront; Zernike aberrations; accommodation; microfluctuations.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhu, M. (2005). Microfluctuations of Wavefront Aberrations of the Eye. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/16121/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zhu, Mingxia. “Microfluctuations of Wavefront Aberrations of the Eye.” 2005. Thesis, Queensland University of Technology. Accessed January 26, 2021.
https://eprints.qut.edu.au/16121/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhu, Mingxia. “Microfluctuations of Wavefront Aberrations of the Eye.” 2005. Web. 26 Jan 2021.
Vancouver:
Zhu M. Microfluctuations of Wavefront Aberrations of the Eye. [Internet] [Thesis]. Queensland University of Technology; 2005. [cited 2021 Jan 26].
Available from: https://eprints.qut.edu.au/16121/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhu M. Microfluctuations of Wavefront Aberrations of the Eye. [Thesis]. Queensland University of Technology; 2005. Available from: https://eprints.qut.edu.au/16121/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology
19.
Shaw, Alyra J. B.
Eyelid pressure on the cornea.
Degree: 2009, Queensland University of Technology
URL: https://eprints.qut.edu.au/31239/
► The eyelids play an important role in lubricating and protecting the surface of the eye. Each blink serves to spread fresh tears, remove debris and…
(more)
▼ The eyelids play an important role in lubricating and protecting the surface of the eye. Each blink serves to spread fresh tears, remove debris and replenish the smooth optical surface of the eye. Yet little is known about how the eyelids contact the ocular surface and what pressure distribution exists between the eyelids and cornea. As the principal refractive component of the eye, the cornea is a major element of the eye’s optics. The optical properties of the cornea are known to be susceptible to the pressure exerted by the eyelids. Abnormal eyelids, due to disease, have altered pressure on the ocular surface due to changes in the shape, thickness or position of the eyelids. Normal eyelids also cause corneal distortions that are most often noticed when they are resting closer to the corneal centre (for example during reading). There were many reports of monocular diplopia after reading due to corneal distortion, but prior to videokeratoscopes these localised changes could not be measured. This thesis has measured the influence of eyelid pressure on the cornea after short-term near tasks and techniques were developed to quantify eyelid pressure and its distribution. The profile of the wave-like eyelid-induced corneal changes and the refractive effects of these distortions were investigated. Corneal topography changes due to both the upper and lower eyelids were measured for four tasks involving two angles of vertical downward gaze (20° and 40°) and two near work tasks (reading and steady fixation). After examining the depth and shape of the corneal changes, conclusions were reached regarding the magnitude and distribution of upper and lower eyelid pressure for these task conditions. The degree of downward gaze appears to alter the upper eyelid pressure on the cornea, with deeper changes occurring after greater angles of downward gaze. Although the lower eyelid was further from the corneal centre in large angles of downward gaze, its effect on the cornea was greater than that of the upper eyelid. Eyelid tilt, curvature, and position were found to be influential in the magnitude of eyelid-induced corneal changes. Refractively these corneal changes are clinically and optically significant with mean spherical and astigmatic changes of about 0.25 D after only 15 minutes of downward gaze (40° reading and steady fixation conditions). Due to the magnitude of these changes, eyelid pressure in downward gaze offers a possible explanation for some of the day-to-day variation observed in refraction. Considering the magnitude of these changes and previous work on their regression, it is recommended that sustained tasks performed in downward gaze should be avoided for at least 30 minutes before corneal and refractive assessment requiring high accuracy. Novel procedures were developed to use a thin (0.17 mm) tactile piezoresistive pressure sensor mounted on a rigid contact lens to measure eyelid pressure. A hydrostatic calibration system was constructed to convert raw digital output of the sensors to actual pressure units.…
Subjects/Keywords: eyelid pressure, cornea, eyelids, corneal topography, videokeratoscopy, near tasks, reading, Marx’s line, eyelid morphology, digital imaging, piezoresistive sensors; ODTA
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Shaw, A. J. B. (2009). Eyelid pressure on the cornea. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/31239/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Shaw, Alyra J B. “Eyelid pressure on the cornea.” 2009. Thesis, Queensland University of Technology. Accessed January 26, 2021.
https://eprints.qut.edu.au/31239/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Shaw, Alyra J B. “Eyelid pressure on the cornea.” 2009. Web. 26 Jan 2021.
Vancouver:
Shaw AJB. Eyelid pressure on the cornea. [Internet] [Thesis]. Queensland University of Technology; 2009. [cited 2021 Jan 26].
Available from: https://eprints.qut.edu.au/31239/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Shaw AJB. Eyelid pressure on the cornea. [Thesis]. Queensland University of Technology; 2009. Available from: https://eprints.qut.edu.au/31239/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Bradford
20.
Serra, Pedro Miguel Fernandes Nave.
Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation.
Degree: PhD, 2013, University of Bradford
URL: http://hdl.handle.net/10454/6331
► The main aim of this thesis is to evaluate the effect of meridional blur, using refractive induced astigmatism, on visual performance at far and close…
(more)
▼ The main aim of this thesis is to evaluate the effect of meridional blur, using refractive induced astigmatism, on visual performance at far and close distances. Visual performance was evaluated using letter discrimination tasks at distance and near (visual acuity, VA) and a reading task at near on subjects with pharmacologically blocked (young) or absent accommodation (presbyopic and pseudophakic). The effect of astigmatism was tested using positive cylindrical lenses oriented at 180 and 90 degrees, these simulating with- (WTR) and against-the-rule (ATR) astigmatism. Other refractive status were also evaluated, namely, in-focus and spherical defocus. The visual performance data were correlated with biometric measurements (pupil size, anterior chamber depth (ACD), corneal and ocular aberrations, corneal multifocality, patient age, axial length). Further, the functionality of meridional blur was evaluated for alphabets in addition to the standard Roman alphabet using a VA task. The results confirm that myopic astigmatism contributes to a better visual performance at closer distances, with ATR astigmatism providing higher performance for reading tasks compared to other forms of astigmatism. Anatomical factors such as pupil size, corneal multifocality and ACD were significantly correlated visual performance, while other ocular characteristics were not. Ray tracing modelling using wavefront data was a moderate predictor of VA and reading acuity. The results of the effect of meridional blur orientation on alphabets other than the Roman alphabet, suggest that visual performance is dependent on the interaction between blur orientation and letter's spatial characteristics. In conclusion, pseudoaccommodation is a multifactorial phenomenon with pupil size being the major contributor for the improvement in visual performance. Against-the-rule shows advantages over WTR astigmatism, by providing higher reading performance, however extending the present and previous findings for clinical application will require further investigation on the effect of meridional blur in common and socio-culturally adapted tasks.
Subjects/Keywords: 617.7; Ocular optical modelling; Cataract; Reading performance; Wavefront aberration; Corneal topography; Accommodation; Visual performance; Astigmatism; Pseudoaccommodation; Pseudoaphakia; Meridional Blur
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Serra, P. M. F. N. (2013). Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation. (Doctoral Dissertation). University of Bradford. Retrieved from http://hdl.handle.net/10454/6331
Chicago Manual of Style (16th Edition):
Serra, Pedro Miguel Fernandes Nave. “Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation.” 2013. Doctoral Dissertation, University of Bradford. Accessed January 26, 2021.
http://hdl.handle.net/10454/6331.
MLA Handbook (7th Edition):
Serra, Pedro Miguel Fernandes Nave. “Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation.” 2013. Web. 26 Jan 2021.
Vancouver:
Serra PMFN. Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation. [Internet] [Doctoral dissertation]. University of Bradford; 2013. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10454/6331.
Council of Science Editors:
Serra PMFN. Visual performance in pseudophakia : the effect of meridional blur in pseudoaccommodation. [Doctoral Dissertation]. University of Bradford; 2013. Available from: http://hdl.handle.net/10454/6331

University of New South Wales
21.
Gifford, Paul.
Short term refractive and corneal topographic changes in hyperopic orthokeratology.
Degree: Optometry & Vision Science, 2009, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/45613
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:8894/SOURCE02?view=true
► Although there is considerable published research on the efficacy and corneal response to orthokeratology (OK) lenses that flatten corneal curvature to correct myopia, the effects…
(more)
▼ Although there is considerable published research on the efficacy and
corneal response to orthokeratology (OK) lenses that flatten
corneal curvature to correct myopia, the effects of OK lenses that attempt to steepen
corneal curvature to correct hyperopia are poorly understood. This project investigated the effects of hyperopic OK lens wear on
corneal shape, refraction and vision. Open-eye and closed-eye overnight studies were conducted with proprietary hyperopic OK lenses, and these led to the development of an experimental hyperopic OK lens design which allowed manipulation of individual lens design parameters. Changes to refraction and best corrected visual acuity (BCVA),
corneal topography (Medmont E300), and the profile of total and stromal
corneal thickness (Holden-Payor optical pachometer) were measured over periods up to one week of overnight lens wear.Most refractive change occurred after the first night of wear, with increasing effect towards one week. Retention of effect at the end of the day increased with more nights of lens wear. BCVA decreased with longer periods of lens wear. Greater inter-
subject variability in effect was found with higher refractive targets. The central cornea steepened and para-central cornea flattened producing a central steepening zone (CSZ) surrounded by a para-central annular flattened zone. CSZ diameter reduced with longer periods of lens wear, and this was significantly associated with decreases in high and low contrast BCVA. There was no change in central
corneal thickness beyond the normal overnight lens induced hypoxic edema response. Once edema had resolved thinning of the para-central
corneal epithelium was found which resulted in an overall thinning of the para-central cornea. Although central lens fenestrations did not affect the hyperopic OK response, a stronger relationship between changes to apical
corneal curvature and refraction resulted. This supports the conclusion that the hyperopic OK effect is due to molding of the
corneal surface towards alignment with the lens back surface. Similarities to the pattern of clinical change in myopic OK suggest that a similar
corneal molding mechanism occurs in myopic OK. BCVA loss prevented longer term studies and needs to be resolved if hyperopic OK is to become established as a viable clinical technique.
Advisors/Committee Members: Swarbrick, Helen, Optometry & Vision Science, Faculty of Science, UNSW, Boneham, Gavin, Optometry & Vision Science, Faculty of Science, UNSW.
Subjects/Keywords: Orthokeratology,; Contact lens,; Hyperopia,; Corneal refractive therapy,; Corneal topography,; Corneal pachometry,; Thesis Digitisation Program
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APA (6th Edition):
Gifford, P. (2009). Short term refractive and corneal topographic changes in hyperopic orthokeratology. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/45613 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:8894/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Gifford, Paul. “Short term refractive and corneal topographic changes in hyperopic orthokeratology.” 2009. Doctoral Dissertation, University of New South Wales. Accessed January 26, 2021.
http://handle.unsw.edu.au/1959.4/45613 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:8894/SOURCE02?view=true.
MLA Handbook (7th Edition):
Gifford, Paul. “Short term refractive and corneal topographic changes in hyperopic orthokeratology.” 2009. Web. 26 Jan 2021.
Vancouver:
Gifford P. Short term refractive and corneal topographic changes in hyperopic orthokeratology. [Internet] [Doctoral dissertation]. University of New South Wales; 2009. [cited 2021 Jan 26].
Available from: http://handle.unsw.edu.au/1959.4/45613 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:8894/SOURCE02?view=true.
Council of Science Editors:
Gifford P. Short term refractive and corneal topographic changes in hyperopic orthokeratology. [Doctoral Dissertation]. University of New South Wales; 2009. Available from: http://handle.unsw.edu.au/1959.4/45613 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:8894/SOURCE02?view=true
22.
Souza, Murilo Barreto.
Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone.
Degree: PhD, Oftalmologia, 2011, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27072011-172605/
;
► INTRODUÇÃO: O ceratocone é uma doença não inflamatória, sem etiologia definida, caracterizada pelo afilamento estromal e protrusão da córnea. Geralmente esta doença torna-se clinicamente evidente…
(more)
▼ INTRODUÇÃO: O ceratocone é uma doença não inflamatória, sem etiologia definida, caracterizada pelo afilamento estromal e protrusão da córnea. Geralmente esta doença torna-se clinicamente evidente na adolescência. Apesar de possuir sinais clínicos bem conhecidos, a detecção do ceratocone em estádios iniciais pode representar uma tarefa de difícil execução, mesmo quando a videoceratografia computadorizada ou outros métodos são utilizados para avaliar a córnea. Anteriormente, diagnosticar o ceratocone apenas após a identificação de sinais clínicos inequívocos era uma conduta aceitável. Com o advento da cirurgia refrativa porém, a identificação precoce do ceratocone tornou-se um procedimento de vital importância para evitar complicações pós-operatórias. O objetivo principal deste estudo é avaliar o uso de máquinas de vetor de suporte e redes neurais artificiais como métodos auxiliares para identificação de ceratocone e suspeita de ceratocone em exames realizados com o Orbscan II. MÉTODOS: Foram avaliados retrospectivamente dados de 344 pacientes. Os exames selecionados foram classificados em 6 categorias: normal (n=172), astigmatismo (n=89), ceratocone (n=46), ceratocone forma frustra (n=10), suspeita de ceratocone (n=16) e cirurgia refrativa (n=11). Para cada paciente 10 atributos foram obtidos ou calculados a partir de dados fornecidos pelo Orbscan II. O método do holdout e da validação cruzada foram utilizados para encontrar a melhor configuração, treinar e testar os classificadores. Além da acurácia, sensibilidade e especificidade, curvas ROC foram obtidas para cada classificador, e as áreas sob as curvas ROC foram calculadas. RESULTADOS: Os dois classificadores selecionados alcançaram um bom desempenho, com áreas sob as curvas ROC de 0,99. Não houve diferença estatística entre as suas performances. O desempenho dos classificadores foi superior ao desempenho de todos os atributos individuais do Orbscan II. (p<0,05). CONCLUSÃO: Os resultados alcançados sugerem que xi x máquinas de vetor de suporte e redes neurais artificiais podem representar técnicas úteis para a detecção de ceratocone em exames realizados com o Orbscan II.
PURPOSE: Keratoconus is a bilateral and non-inflammatory condition characterized by progressive thinning, protrusion and scarring of the córnea. The disease usually becomes clinically evident at puberty, and its etiology remains unknown. Although it has well-described clinical signs, early forms of the disease may be undetected, even when computer-assisted videokeratography techniques or other methods are used to evaluate the cornea. Prior to the development of refractive surgery, it was considered sufficient to diagnose clinically evident keratoconus. However, given the spread of refractive surgery, a careful differentiation between normal and early keratoconus cases is essential to avoid postoperative complications. This study evaluated the performance of support vector machine and multilayer perceptron neural network, as auxiliary tools to identify keratoconus from Orbscan II maps. METHODS:…
Advisors/Committee Members: Alves, Milton Ruiz.
Subjects/Keywords: Artificial intelligence; Ceratocone; Computer-assisted diagnosis; Corneal topography; Diagnosis; Diagnóstico; Diagnóstico por computador; Inteligência artificial; Keratoconus; Neural networks; Redes neurais; Topografia da córnea
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Souza, M. B. (2011). Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27072011-172605/ ;
Chicago Manual of Style (16th Edition):
Souza, Murilo Barreto. “Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone.” 2011. Doctoral Dissertation, University of São Paulo. Accessed January 26, 2021.
http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27072011-172605/ ;.
MLA Handbook (7th Edition):
Souza, Murilo Barreto. “Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone.” 2011. Web. 26 Jan 2021.
Vancouver:
Souza MB. Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone. [Internet] [Doctoral dissertation]. University of São Paulo; 2011. [cited 2021 Jan 26].
Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27072011-172605/ ;.
Council of Science Editors:
Souza MB. Rede de aprendizado supervisionado como método de auxilio na detecção do ceratocone. [Doctoral Dissertation]. University of São Paulo; 2011. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27072011-172605/ ;
23.
Santos, Luiz Eduardo Ribeiro dos.
Desenvolvimento de um videoceratógrafo de córnea.
Degree: Mestrado, Física Aplicada, 1997, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/76/76132/tde-12052014-170243/
;
► O objetivo deste trabalho e desenvolver um instrumento computadorizado para análise da superfície anterior da córnea humana, gerando para isto, um mapa topográfico bidimensional em…
(more)
▼ O objetivo deste trabalho e desenvolver um instrumento computadorizado para análise da superfície anterior da córnea humana, gerando para isto, um mapa topográfico bidimensional em código de cores. Utilizando a córnea como um espelho esférico convexo, projeta-se anéis luminosos sobre sua superfície e aquisiciona-se com uma câmera a imagem por ela refletida. Esta imagem e digitalizada e armazenada em um microcomputador para posterior processamento. Através de técnicas de computação gráfica e processamento de imagens digitais, extrai-se da imagem as informações necessárias para construção da topografia desejada. Por fim, a topografia e apresentada em forma de mapas coloridos, sendo cada cor associada a uma determinada dioptria, transmitindo ao médico oftalmologista uma noção exata da superfície da córnea do paciente em análise.
The main goal of this work is to develop a computerized instrument for the analysis of the anterior portion of the human cornea, which displays its result in topographic color maps. Approximating the cornea to a spherical convex mirror, and by projecting a known pattern over it, the reflected image is captured and stored. By means of computer graphics technology and image processing, the necessary information for mathematical calculations is extracted. The resulting maps are color-coded in accordance to the degree of power of each corneal region, that is, to the diopter value. The ophthalmologist can then make important diagnostics and surgery tactics from the analysis of these topographic maps.
Advisors/Committee Members: Castro Neto, Jarbas Caiado de.
Subjects/Keywords: Corneal topography; Curvatura de córnea; Curvature of the cornea; Topografia de córnea
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Santos, L. E. R. d. (1997). Desenvolvimento de um videoceratógrafo de córnea. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/76/76132/tde-12052014-170243/ ;
Chicago Manual of Style (16th Edition):
Santos, Luiz Eduardo Ribeiro dos. “Desenvolvimento de um videoceratógrafo de córnea.” 1997. Masters Thesis, University of São Paulo. Accessed January 26, 2021.
http://www.teses.usp.br/teses/disponiveis/76/76132/tde-12052014-170243/ ;.
MLA Handbook (7th Edition):
Santos, Luiz Eduardo Ribeiro dos. “Desenvolvimento de um videoceratógrafo de córnea.” 1997. Web. 26 Jan 2021.
Vancouver:
Santos LERd. Desenvolvimento de um videoceratógrafo de córnea. [Internet] [Masters thesis]. University of São Paulo; 1997. [cited 2021 Jan 26].
Available from: http://www.teses.usp.br/teses/disponiveis/76/76132/tde-12052014-170243/ ;.
Council of Science Editors:
Santos LERd. Desenvolvimento de um videoceratógrafo de córnea. [Masters Thesis]. University of São Paulo; 1997. Available from: http://www.teses.usp.br/teses/disponiveis/76/76132/tde-12052014-170243/ ;

University of Waterloo
24.
Priest, A. David.
The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model.
Degree: 2005, University of Waterloo
URL: http://hdl.handle.net/10012/1211
► The purpose of this thesis is to describe the development of an anatomically based, young adult eye model, which includes a crystalline lens with a…
(more)
▼ The purpose of this thesis is to describe the development of an anatomically based, young adult eye model, which includes a crystalline lens with a gradient refractive index (GRIN). This model will then be used to investigate the effect of laser refractive surgery.
The first step in this process involved developing a symmetrical eye model that was found to be a better predictor of empirical longitudinal spherical aberration than any previous model. Myopia was simulated by either a purely axial or refractive technique. While these models were found to be good predictors of the spherical aberration measured in young adults, they did not predict the total amount of high-order aberrations. The techniques used to simulate a single type of myopia caused the myopic models to become anatomically inaccurate.
To improve the eye models a biconic surface was used to quantify the anterior corneal shape as a function of myopia. A method to describe the refractive error and biconic shape parameters in Jackson Cross Cylinder terms was implemented to determine correlations. Results indicate that a biconic accurately models the average shape of the anterior corneal surface as a function of myopia.
Adopting the biconic model for the anterior corneal surface and adding average misalignments of the ocular components transformed the models from symmetrical to asymmetrical. Refractive error was now simulated by the anatomically accurate changes in both the anterior corneal shape and axial length. The asymmetrical aberrations resulted from the misalignment of the ocular components and provided a good prediction of average empirical aberrations but underestimated the aberrations of individual subjects.
Photorefractive keratectomy, a form of laser refractive surgery, was simulated by theoretically calculated and by empirically measured changes in the shape of the anterior corneal surface. Applying the change in anterior corneal shape to the asymmetrical models was used to develop postoperative models. Changes in corneal shape and model aberrations attributed to theoretical calculations do not match empirical observations. The prediction of increased high-order aberrations in postoperative models based on empirically measured changes in the anterior corneal topography was similar to clinical results.
Average anatomically based, GRIN eye models have been developed that accurately predict the average aberrations of emmetropic and myopic young adults. These models underestimate the asymmetrical and total high-order aberrations that have been measured in individual subjects but are still useful for investigating the average effects of procedures like refractive surgery.
Subjects/Keywords: Physics & Astronomy; gradient refractive index; GRIN; eye model; corneal topography; refractive surgery
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Priest, A. D. (2005). The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/1211
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Priest, A David. “The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model.” 2005. Thesis, University of Waterloo. Accessed January 26, 2021.
http://hdl.handle.net/10012/1211.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Priest, A David. “The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model.” 2005. Web. 26 Jan 2021.
Vancouver:
Priest AD. The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model. [Internet] [Thesis]. University of Waterloo; 2005. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10012/1211.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Priest AD. The Development of an
Average, Anatomically Based, Young Adult, GRIN
Eye Model. [Thesis]. University of Waterloo; 2005. Available from: http://hdl.handle.net/10012/1211
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queensland University of Technology
25.
Read, Scott A.
Corneal topography and the morphology of the palpebral fissure.
Degree: 2006, Queensland University of Technology
URL: https://eprints.qut.edu.au/16203/
► The notion that forces from the eyelids can alter the shape of the cornea has been proposed for many years. In recent times, there has…
(more)
▼ The notion that forces from the eyelids can alter the shape of the cornea has been proposed for many years. In recent times, there has been a marked improvement in our ability to measure and define the corneal shape, allowing subtle changes in the cornea to be measured. These improvements have led to the findings that pressure from the eyelids can cause alterations in corneal shape following everyday visual tasks such as reading. There are also theories to suggest that pressure from the eyelids may be involved in the aetiology of corneal astigmatism. In this program of research, a series of experiments were undertaken to investigate the influence of the eyelids on the shape of the cornea.
In the first experiment, an investigation into the diurnal variation of corneal shape was carried out by measuring corneal topography at three different times (approximately 9 am, 1 pm and 5 pm) during the day over three days of the week (Monday, Tuesday and Friday). Highly significant diurnal changes were found to occur in the corneal topography of 15 of the 17 subjects. This change typically consisted of horizontal bands of distortion in the superior, and to a lesser extent, inferior cornea, increasing throughout the day (and returning to baseline the next morning). These changes appeared to be related to forces from the eyelids on the anterior cornea. Some changes were also found in corneal astigmatism. Corneal astigmatism power vector J0 (astigmatism 90/180°) was found to increase slightly over the course of the week. Whilst the changes in astigmatism were small in magnitude, this result leaves open the possibility that pressure from the eyelid may cause changes in corneal astigmatism. If pressure from the eyelids is involved in the aetiology of corneal astigmatism, then one may expect associations to exist between certain characteristics of the eyelids and corneal shape. An experiment was then undertaken to explore these possible associations.
We defined the average morphology of the palpebral fissure in different angles of vertical gaze for 100 young normal subjects. This was achieved through analysis of digital images that were captured in primary gaze, 20° downgaze and 40° downgaze. Parameters defining the size, position, angle and contour of the eyelids were determined. Highly significant changes were found to occur in the palpebral fissure with downward gaze. The palpebral aperture narrows in downward gaze, and the angle of the eyelids changes from being slightly upward slanted in primary gaze, to being slightly downward slanted in downward gaze. The eyelid margin contour also flattens significantly in downward gaze.
The average topography of the central and peripheral cornea was also defined for this same population. A technique was used that allowed the capture and subsequent combination of topography data from both the central and the peripheral cornea. The use of this technique provided a large corneal topography map, with data extending close to the limbus for each subject. Marked flattening was found to…
Subjects/Keywords: cornea; astigmatism; aberrations; eyelids; corneal topography; videokeratoscopy; digital imaging; eyelid morphology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Read, S. A. (2006). Corneal topography and the morphology of the palpebral fissure. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/16203/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Read, Scott A. “Corneal topography and the morphology of the palpebral fissure.” 2006. Thesis, Queensland University of Technology. Accessed January 26, 2021.
https://eprints.qut.edu.au/16203/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Read, Scott A. “Corneal topography and the morphology of the palpebral fissure.” 2006. Web. 26 Jan 2021.
Vancouver:
Read SA. Corneal topography and the morphology of the palpebral fissure. [Internet] [Thesis]. Queensland University of Technology; 2006. [cited 2021 Jan 26].
Available from: https://eprints.qut.edu.au/16203/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Read SA. Corneal topography and the morphology of the palpebral fissure. [Thesis]. Queensland University of Technology; 2006. Available from: https://eprints.qut.edu.au/16203/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ)
26.
Μάμτζιου, Ευφροσύνη.
Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς.
Degree: 2000, Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ)
URL: http://hdl.handle.net/10442/hedi/25429
Subjects/Keywords: Τοπογραφία κερατοειδούς; Χρωματικός τοπογραφικός χάρτης; Τοπογραφικό σχήμα; Στατιστικοί τοπογραφικοί δείκτες; Ασφαιρικότης κερατοειδούς; Corneal topography; Color-coded topographic map; Topographic pattern; Corneal statistical indices; Asphericity of corneal
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Μάμτζιου, . . (2000). Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς. (Thesis). Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ). Retrieved from http://hdl.handle.net/10442/hedi/25429
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Μάμτζιου, Ευφροσύνη. “Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς.” 2000. Thesis, Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ). Accessed January 26, 2021.
http://hdl.handle.net/10442/hedi/25429.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Μάμτζιου, Ευφροσύνη. “Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς.” 2000. Web. 26 Jan 2021.
Vancouver:
Μάμτζιου . Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς. [Internet] [Thesis]. Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ); 2000. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10442/hedi/25429.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Μάμτζιου . Τοπογραφία του κερατοειδούς: μια νέα μέθοδος στην απεικόνιση του φυσιολογικού και παθολογικού κερατοειδούς. [Thesis]. Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ); 2000. Available from: http://hdl.handle.net/10442/hedi/25429
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
Medeiros, Fabricio Witzel de.
Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.
Degree: PhD, Oftalmologia, 2011, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/
;
► Objetivo: Investigar as alterações biomecânicas da córnea de suínos induzidas pela confecção de lamelas pediculadas de diferentes espessuras pelo laser de femtossegundo. Métodos: Para a…
(more)
▼ Objetivo: Investigar as alterações biomecânicas da córnea de suínos induzidas pela confecção de lamelas pediculadas de diferentes espessuras pelo laser de femtossegundo. Métodos: Para a formação dos dois grupos, 12 olhos de porcos foram usados: lamelas pediculadas de 100 e de 300 micrômetros confeccionadas pelo laser de femtossegundo. Cada olho foi submetido aos seguintes exames, antes da criação das lamelas: topografia por rasterstereography, Ocular Response Analyzer (ORA), tomografia do segmento anterior por coerência óptica para a avaliação paquimétrica corneal e das lamelas criadas e sistema de velocidade de onda (SVO), que mede a velocidade de propagação de ondas acústicas entre dois transdutores posicionados na superfície corneal antes e imediatamente, após a feitura da lamela. O primerio passo foi desenhado para o estudo das diferenças em relação à histerese corneal, fator de resistência corneal, mudanças na curvatura e velocidade de propagação de onda acústica entre córneas com lamelas finas e espessas. Posteriormente, as lamelas foram amputadas, e as medidas do sistema de velocidade de onda foram repetidas. Resultados: A média de espessura das lamelas ± desviopadrão (DP) foi de 108,5±6,9 (8,5% da espessura total) e 307,8±11,5 m (22,9% da espessura total), para os grupos de lamelas finas e espessas, respectivamente (p< 0,001). Histerese corneal e o fator de resistência corneal não apresentaram diferença estatística, após a criação de lamelas finas (p = 0,81 e p = 0,62, respectivamente). Histerese corneal foi significantemente mais baixa, depois da confecção de lamelas mais espessas (8,0±1,0 para 5,1±1,5 mmHg para medidas pré e pós-operatórias, respectivamente, p = 0,003, diminuição de 36,25%) e fator de resistência corneal também mostrou significante diminuição nesse grupo, após o procedimento cirúrgico; valores médios pré e pós-operatórios de 8,2±1,6 e 4,1±2,5 mmHg respectivamente (p= 0,007), diminuição de 50%. A ceratometria média simulada apresentou maiores valores, após a confecção das lamelas mais espessas em relação ao pré-operatório (ceratometria pré e pós-operatória de 39,5±1 D e 45,9±1,2 D, respectivamente, p= 0,003). Para o grupo de lamelas finas, não houve diferença estatisticamente significante (ceratometria pré e pós-operatória de 40,6±0,6 D e 41,4±1,0 D, respectivamente, p=0,55). Em relação ao Sistema de Velocidade de Onda, após a criação das lamelas e sua amputação, houve diminuição da velocidade de propagação acústica, embora na maior parte das posições não fosse estatisticamente significante. Conclusão: Nas condições experimentais estabelecidas por este estudo, a criação de lamelas de maior espessura pareceu exercer efeito mais relevante sobre a biomecânica da córnea de suínos
Purpose: To study the impact of programmed flaps at two different thicknesses on the biomechanical properties of the swine corneas. Methods: Twelve pig eyes were enrolled in this study and were formed two groups: 100m and 300 m flaps performed with the femtosecond laser. Each eye had the following procedure before…
Advisors/Committee Members: Alves, Milton Ruiz.
Subjects/Keywords: Biomecânica; Biomechanics; Ceratomileuse assistida por excimer laser in situ; Cirurgia refrativa; Cornea; Córnea; Corneal topography; Ectasia; Ectasia; Flaps; Histerese; Histeresis; Lamelas pediculadas; Laser-assisted in situ keratomileusis; Pachymetry; Paquimetria; Refractive surgery; Topografia da córnea
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Medeiros, F. W. d. (2011). Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;
Chicago Manual of Style (16th Edition):
Medeiros, Fabricio Witzel de. “Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.” 2011. Doctoral Dissertation, University of São Paulo. Accessed January 26, 2021.
http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;.
MLA Handbook (7th Edition):
Medeiros, Fabricio Witzel de. “Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.” 2011. Web. 26 Jan 2021.
Vancouver:
Medeiros FWd. Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. [Internet] [Doctoral dissertation]. University of São Paulo; 2011. [cited 2021 Jan 26].
Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;.
Council of Science Editors:
Medeiros FWd. Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. [Doctoral Dissertation]. University of São Paulo; 2011. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;
28.
Kounis, Georgios.
Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία.
Degree: 2007, University of Crete (UOC); Πανεπιστήμιο Κρήτης
URL: http://hdl.handle.net/10442/hedi/24861
► Purpose. To describe a new software tool for the detailed presentation of corneal topography measurements variability by means of color coded maps. Methods. Software was…
(more)
▼ Purpose. To describe a new software tool for the detailed presentation of corneal topography measurements variability by means of color coded maps. Methods. Software was developed in Visual Basic to analyze and process a series of 10 consecutive measurements obtained by a topographic system on calibration spheres and individuals with emmetropic low high and irregular astigmatic corneas Corneal surface was segmented into 1200 segments and the coefficient of variance of each segment’s keratometric dioptric power was used as the measure of variability. The results were presented graphically in color coded maps (Variability Maps). Two topographic systems the TechnoMed C-Scan and the TOMEY Topographic Modeling System (TMS-2Ν) were examined to demonstrate our method. Results. Graphic representation of coefficient of variance offered a detailed representation of examination variability both in calibration surfaces and human corneas. It was easy to recognize an increase in variability as the irregularity of examination surfaces increased. In individuals with high and irregular astigmatism a variability pattern correlated with the pattern of corneal topography, steeper corneal areas possessed higher variability values compared with flatter areas of the same cornea. Numerical data permitted direct comparisons and statistical analysis. Conclusions. We propose a method that permits a detailed evaluation of the variability of corneal topography measurements. The representation of the results both graphically and quantitatively improves interpretability and facilitates a spatial correlation of variability maps with original topography maps. Given the popularity of topography based custom refractive ablations of the cornea it is possible that variability maps may assist clinicians in the evaluation of corneal topography maps of patients with very irregular corneas before custom ablation procedures.
Σκοπός. Ο προσδιορισμός της επαναληψιμότητας τοπογραφικών συστημάτων μέσω ενός λογισμικού που χρησιμοποιεί ανάλυση σημείο-προς σημείο των εξαχθέντων πρωτευόντων δεδομένων (Raw Data). Μέθοδοι. Ένας εξεταστής λαμβάνει 10 διαδοχικές τοπογραφικές μετρήσεις με δυο τοπογραφικά συστήματα το TechnoMed C Scan και το Tomey Topographic Modeling System (TMS-2N) σε σφαίρες βαθμονόμησης, σε εμμετροπικούς, μυωπικούς, αστιγματικούς και σε πολύ ανώμαλης επιφάνειας κερατοειδείς. Ο κερατοειδής χωρίζεται σε 1200 τμήματα και για κάθε τμήμα υπολογίζεται: η μέση τιμή, η τυπική απόκλιση και ο συντελεστής μεταβλητότητας (coefficient of variation) μέσω λογισμικού που αναπτύχθηκε σε γλωσσά προγραμματισμού Visual Basic 6.0. Τα αποτελέσματα εκφράζονται και αριθμητικά και γραφικά υπό τη μορφή έγχρωμων χαρτών που είναι παρόμοιοι με αυτούς της τοπογραφίας και η επαναληψιμότητα εκφράζεται μέσω του συντελεστή μεταβλητότητας. Αποτελέσματα. Ακόμη και αν οι σφαίρες βαθμονόμησης έχουν καλύτερα αποτελέσματα ως προς τη επαναληψιμότητα (CoV<0 5%) σε σχέση με τους κερατοειδείς (CoV>0 5%), υπάρχουν και περιοχές όπου η επαναληψιμότητα μειώνεται αισθητά (CoV>1.25%D). Το…
Subjects/Keywords: Κερατοειδική τοπογραφία; Βιντεοκερατοσκόπιο; Επαναληψιμότητα μετρήσεων; Corneal topography; Videokeratoscopy; Repeatability - reproducibility of measurements; Computer - assisted / instrumentation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kounis, G. (2007). Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία. (Thesis). University of Crete (UOC); Πανεπιστήμιο Κρήτης. Retrieved from http://hdl.handle.net/10442/hedi/24861
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kounis, Georgios. “Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία.” 2007. Thesis, University of Crete (UOC); Πανεπιστήμιο Κρήτης. Accessed January 26, 2021.
http://hdl.handle.net/10442/hedi/24861.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kounis, Georgios. “Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία.” 2007. Web. 26 Jan 2021.
Vancouver:
Kounis G. Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία. [Internet] [Thesis]. University of Crete (UOC); Πανεπιστήμιο Κρήτης; 2007. [cited 2021 Jan 26].
Available from: http://hdl.handle.net/10442/hedi/24861.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kounis G. Μελέτη της επαναληψιμότητας μετρήσεων τοπογραφικών συστημάτων του κερατοειδούς στην οφθαλμολογία. [Thesis]. University of Crete (UOC); Πανεπιστήμιο Κρήτης; 2007. Available from: http://hdl.handle.net/10442/hedi/24861
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Freie Universität Berlin
29.
Schründer, Stephan Alexander.
Corneal topometry using ultraviolet fringe projection.
Degree: 2008, Freie Universität Berlin
URL: http://dx.doi.org/10.17169/refubium-4994
► Refractive laser surgery has become a wide spread application to correct vision errors like nearsightedness at the corneal level. Unfortunately there is no guarantee as…
(more)
▼ Refractive laser surgery has become a wide spread application to correct
vision errors like nearsightedness at the
corneal level. Unfortunately there
is no guarantee as to whether the laser ablation leads to a favorable outcome.
Until today there is no online procedure control. This dissertation presents a
new method to measure the
corneal and scleral surface shape during refractive
laser procedures in an attempt to use it as an online monitoring feature. A
preliminary clinical study has show the potential of the method. Biomechanical
side effects of the microkeratom cut during LASIK interfere with the online
surface shape measurements. Hence a refined approach is necessary to use the
full potential of the method. Different side effects of the laser treatment
have been illustrated and quantified for the first time. Further studies are
necessary to establish the method on a broader basis.
Advisors/Committee Members: n (gender), Prof. Dr. Friedrich Hoffmann (firstReferee), PD Dr. Ebba Schwarz (furtherReferee).
Subjects/Keywords: Corneal Topography; Fringe Projection; Ultraviolet; Laser; LASIK; 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Schründer, S. A. (2008). Corneal topometry using ultraviolet fringe projection. (Thesis). Freie Universität Berlin. Retrieved from http://dx.doi.org/10.17169/refubium-4994
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Schründer, Stephan Alexander. “Corneal topometry using ultraviolet fringe projection.” 2008. Thesis, Freie Universität Berlin. Accessed January 26, 2021.
http://dx.doi.org/10.17169/refubium-4994.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Schründer, Stephan Alexander. “Corneal topometry using ultraviolet fringe projection.” 2008. Web. 26 Jan 2021.
Vancouver:
Schründer SA. Corneal topometry using ultraviolet fringe projection. [Internet] [Thesis]. Freie Universität Berlin; 2008. [cited 2021 Jan 26].
Available from: http://dx.doi.org/10.17169/refubium-4994.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Schründer SA. Corneal topometry using ultraviolet fringe projection. [Thesis]. Freie Universität Berlin; 2008. Available from: http://dx.doi.org/10.17169/refubium-4994
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
30.
Dantas, Paulo Elias Corrêa.
Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal.
Degree: PhD, Oftalmologia, 2002, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-07032002-002915/
;
► Doença alérgica ocular acomete cerca de ¼ da população mundial. Dentro do espectro da doença alérgica ocular, a cérato-conjuntivite vernal, que afeta principalmente crianças, pode…
(more)
▼ Doença alérgica ocular acomete cerca de ¼ da população mundial. Dentro do espectro da doença alérgica ocular, a cérato-conjuntivite vernal, que afeta principalmente crianças, pode apresentar-se sob forma severa e persistente, levando a dano do tecido corneal e comprometimento da função visual. Traumatismo epitelial crônico, induzido pelo ato de coçar os olhos, associado ao intenso prurido ocular tem sido apontado como fator de risco importante na patogênese do ceratocone. Pode estimular a apoptose prematura dos ceratócitos, provocando mudanças estruturais do estroma da córnea. A associação de cérato-conjuntivite vernal e ceratocone tem sido apontada como freqüente na literatura oftalmológica através de estudos descritivos e qualitativos, que, entretanto, não auxiliam na detecção precoce da doença ectásica corneal, prejudicando sua análise epidemiológica, seu estudo genético e a definição de sua patogênese. Propôs-se estudo clínico caso-controle de pacientes com cérato-conjuntivite vernal do Ambulatório de Alergia Ocular do Departamento de Oftalmologia da Santa Casa de São Paulo, com finalidade de obter-se, por meio da análise topográfica computadorizada de córnea utilizando-se de descritor quantitativo da superfície anterior da córnea (sumário diagnóstico de Holladay), informações sobre as alterações topográficas da superfície anterior da córnea, que pudessem determinar a freqüência da associação entre cérato-conjuntivite vernal e ceratocone, além de seus efeitos sobre o desempenho da visão destes pacientes. Os resultados obtidos neste estudo mostram alta freqüência de ceratocone em pacientes com cérato-conjuntivite vernal. A performance visual destes pacientes é influenciada pelas aberrações provocadas por alterações da asfericidade corneal e de outras variáveis topográficas.
Allergic ocular disease affects ¼ of the world population. Inside the spectrum of the allergic ocular disease, vernal keratoconjunctivitis, that affects mostly children, may present as severe and persistent form, leading to corneal tissue damage and disturbing visual function. Chronic epithelial trauma, provoked by eye rubbing due to intense ocular itching, has been postulated as an important risk factor in the pathogenesis of keratoconus. It may induce early keratocyte apoptosis that results in structural changes to the corneal stroma. The association of keratoconus with vernal keratoconjunctivitis has been observed to be frequent in the ophthalmological literature by descriptive and qualitative studies, unable to detect earlier forms of this ectatic corneal disease, weakening epidemiological analysis, genetic studies and the definition of its pathogenesis. We proposed a case-control clinical study of patients with vernal keratoconjunctivitis from the Ambulatory of Ocular Allergy of the Department of Ophthalmology of Santa Casa of São Paulo, aiming for information on the anterior corneal curvature and visual performance, using a quantitative descriptor analyzer (Holladay Diagnostic Summary). The results suggest high frequency of the…
Advisors/Committee Members: Alves, Milton Ruiz.
Subjects/Keywords: allergic conjunctivitis; ceratocone/diagnóstico; ceratocone/epidemiologia; conjuntivite alérgica/diagnóstico; conjuntivite alérgica/epidemiologia; corneal disease; corneal topography; doenças da córnea/diagnóstico; doenças da córnea/epidemiologia; keratoconus; topografia da córnea/estatística e dados numéricos
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Dantas, P. E. C. (2002). Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5149/tde-07032002-002915/ ;
Chicago Manual of Style (16th Edition):
Dantas, Paulo Elias Corrêa. “Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal.” 2002. Doctoral Dissertation, University of São Paulo. Accessed January 26, 2021.
http://www.teses.usp.br/teses/disponiveis/5/5149/tde-07032002-002915/ ;.
MLA Handbook (7th Edition):
Dantas, Paulo Elias Corrêa. “Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal.” 2002. Web. 26 Jan 2021.
Vancouver:
Dantas PEC. Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal. [Internet] [Doctoral dissertation]. University of São Paulo; 2002. [cited 2021 Jan 26].
Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-07032002-002915/ ;.
Council of Science Editors:
Dantas PEC. Alterações topográficas da córnea em pacientes com cérato-conjuntivite vernal. [Doctoral Dissertation]. University of São Paulo; 2002. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-07032002-002915/ ;
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