subject:(Tear film)

University of Waterloo

1. Jabeen, Asiya. Studies on the Optimization of Neuropeptides Detection in the Human Tear Film.

Degree: 2020, University of Waterloo

► Introduction: Dry Eye Disease (DED) stems from a disruption of the homeostasis of the tear film (TF), a thin layer of fluid covering the ocular… (more)

▼ Introduction: Dry Eye Disease (DED) stems from a disruption of the homeostasis of the tear film (TF), a thin layer of fluid covering the ocular surface. The TF consists of numerous constituents that include proteins, lipids, mucins, water, electrolytes, immunoglobulins, vitamins, cytokines, and neuropeptides. An imbalance in any of these constituents could result in an unstable tear film, contributing to the pathophysiology of DED. Among these factors, neuropeptides, small proteinaceous substances produced and released by neurons through regulated secretory routes, may have a role in the pathophysiology of DED. To understand the impact of the disease on the concentrations of calcitonin gene-related peptide (CGRP), substance P (SP), neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP) in the tear film, it is important to first understand the sample collection and quantification methods. The purpose of this thesis was to optimize a method to quantify the concentration of four neuropeptides using enzyme linked immunosorbent assay (ELISA). a common laboratory technique used to quantify the concentration of neuropeptides in the tear film. ELISAs have been used to determine the quantity of different components in blood and other bodily fluids in the human tear film. The aims of each chapter were as follows: Chapter 3: To determine the variability of two tear collection methods, basal tear collection and flush tear collection, for quantifying SP, CGRP, VIP, and NPY, and to quantify the day-to-day variability of these neuropeptides. Chapter 4: To assess the validity of a commercially available ELISA kits for the quantification of neuropeptides. Chapter 5: To examine the measurement variability of two commercially available ELISA kits for the quantification of SP. Methods: Chapter 3: Basal and flush tears (following instillation of 20 μL of saline on the ocular surface) of 8 healthy participants were collected from the right and left eyes respectively, using glass microcapillary tubes on two consecutive days. The concentrations of the four neuropeptides in the tears were determined using ELISA, for both collection methods, and for both days. Chapter 4: Basal tears (5 µL) were collected from the temporal canthus of each eye of 3 healthy participants using glass microcapillary tubes. To assess the validity of the ELISA kit used in Chapter 3, two experiments were performed: a spike and recovery experiment, followed by a serial dilution response. In the spike and recovery experiment, 2 μL of tears from each participant were diluted in 108 μL of three known concentrations of SP, CGRP, and NPY (1 pg/mL, 10 pg/mL, and 100 pg/mL). The concentrations of neuropeptides were quantified using ELISA and the percent recovery was calculated. In the serial dilution response experiment, 4 μL of tears were collected from a single participant and was spiked into a known concentration of NPY (100 pg/mL). Serial dilutions (1:2, 1:4 and 1:8) were conducted and the percent recovery was calculated. Multiple troubleshooting and…

Subjects/Keywords: neuropeptides; elisa; optimization; tear film

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APA (6^th Edition):

Jabeen, A. (2020). Studies on the Optimization of Neuropeptides Detection in the Human Tear Film. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15832

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jabeen, Asiya. “Studies on the Optimization of Neuropeptides Detection in the Human Tear Film.” 2020. Thesis, University of Waterloo. Accessed February 27, 2021. http://hdl.handle.net/10012/15832.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jabeen, Asiya. “Studies on the Optimization of Neuropeptides Detection in the Human Tear Film.” 2020. Web. 27 Feb 2021.

Vancouver:

Jabeen A. Studies on the Optimization of Neuropeptides Detection in the Human Tear Film. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10012/15832.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jabeen A. Studies on the Optimization of Neuropeptides Detection in the Human Tear Film. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/15832

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. Arumugam Balasubramanian, Sivaraman. Changes to the tear film proteome in keratoconus.

Degree: Optometry & Vision Science, 2012, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/52170 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10840/SOURCE01?view=true

► Keratoconus (KC) is a progressive degenerative disease of the eye which causes an irregularly shaped cornea leading to severe impairment of vision. Despite basic and… (more)

▼ Keratoconus (KC) is a progressive degenerative disease of the eye which causes an irregularly shaped cornea leading to severe impairment of vision. Despite basic and clinical studies KC remains a poorly understood disease. This project was designed to investigate the levels of proteins, proteases and cytokines in the tears of people with KC.Basal tears were collected from normal controls (C); people with KC and from people who had undergone corneal collagen cross-linking (CXL) for the treatment of KC. Corneal curvature of each subject was mapped. Proteomic technologies including gel electrophoresis, ELISA, mass spectrometry, antibody arrays and activity assays were used to examine the changes in tear proteins, proteases and cytokines between the different subject groups. There was approximately 2-fold decrease in total protein levels, lactoferrin, secretory IgA between KC and C tears, but the level of albumin was not significantly reduced. The tear protein changes correlated to the severity of the disease. Increased levels of cathepsin B (2.7-fold) and decreased levels of cystatin S (2.1-fold) and cystatin SN (2-fold), polymeric immunoglobulin receptor (9.4-fold), fibrinogen alpha chain (8.2-fold) were observed in KC compared to C. Keratin type-1 cytoskelatal-14 and keratin type-2 cytoskeletal-5 was present only in the tears of KC. Tears of people with KC had 1.9 times higher levels of proteolytic activity and over-expression of several matrix metalloproteinases (MMP) -1, -3, -7, -13 and interleukins (IL) -4, -5, -6, -7, -8 and tumour necrosis factor (TNF) -α, -β compared to tears from C. No significant difference in MMPs were observed between the C and CXL groups, although the expression levels of TNF-α was 1.5 times increased in CXL compared to C. The activity of tear proteases in CXL were not significantly different compared to either KC or C subjects.The tears of people with KC appear to have an altered tear protein profile, higher levels of proteases and cytokines that might reflect the pathological events in KC corneas. The novel findings reported in this thesis might lead the way to the development of non-invasive diagnostic or prognostic tests for KC or determine the success of CXL using tear proteomics. Advisors/Committee Members: Pye, David, Optometry & Vision Science, Faculty of Science, UNSW.

Subjects/Keywords: Proteomics; Keratoconus; Tear film

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APA (6^th Edition):

Arumugam Balasubramanian, S. (2012). Changes to the tear film proteome in keratoconus. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52170 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10840/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

Arumugam Balasubramanian, Sivaraman. “Changes to the tear film proteome in keratoconus.” 2012. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2021. http://handle.unsw.edu.au/1959.4/52170 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10840/SOURCE01?view=true.

MLA Handbook (7^th Edition):

Arumugam Balasubramanian, Sivaraman. “Changes to the tear film proteome in keratoconus.” 2012. Web. 27 Feb 2021.

Vancouver:

Arumugam Balasubramanian S. Changes to the tear film proteome in keratoconus. [Internet] [Doctoral dissertation]. University of New South Wales; 2012. [cited 2021 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/52170 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10840/SOURCE01?view=true.

Council of Science Editors:

Arumugam Balasubramanian S. Changes to the tear film proteome in keratoconus. [Doctoral Dissertation]. University of New South Wales; 2012. Available from: http://handle.unsw.edu.au/1959.4/52170 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10840/SOURCE01?view=true

University of New South Wales

3. Wei, Xiaojia Eric. Biochemical studies of the tear film in humans and rabbits.

Degree: Optometry & Vision Science, 2012, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/52715 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11388/SOURCE01?view=true

► Clinically, a decrease in tear film stability has been associated with both dry eye and contact lens discontinuation. Rabbits are known to have a significantly… (more)

Subjects/Keywords: Biochemistry; Tear film; Stability

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wei, X. E. (2012). Biochemical studies of the tear film in humans and rabbits. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52715 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11388/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

Wei, Xiaojia Eric. “Biochemical studies of the tear film in humans and rabbits.” 2012. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2021. http://handle.unsw.edu.au/1959.4/52715 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11388/SOURCE01?view=true.

MLA Handbook (7^th Edition):

Wei, Xiaojia Eric. “Biochemical studies of the tear film in humans and rabbits.” 2012. Web. 27 Feb 2021.

Vancouver:

Wei XE. Biochemical studies of the tear film in humans and rabbits. [Internet] [Doctoral dissertation]. University of New South Wales; 2012. [cited 2021 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/52715 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11388/SOURCE01?view=true.

Council of Science Editors:

Wei XE. Biochemical studies of the tear film in humans and rabbits. [Doctoral Dissertation]. University of New South Wales; 2012. Available from: http://handle.unsw.edu.au/1959.4/52715 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11388/SOURCE01?view=true

Virginia Tech

4. Brantman, Karen Renee. Tear Film VEGF in Dogs with Vascularizing Corneal Disease.

Degree: MS, Biomedical and Veterinary Sciences, 2013, Virginia Tech

URL: http://hdl.handle.net/10919/23166

► This body of work encompasses two studies: the collection of canine tears via a novel polyester rod and the comparison of VEGF-A concentrations in tears… (more)

Subjects/Keywords: VEGF; tear film; canine corneal vascularization

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APA (6^th Edition):

Brantman, K. R. (2013). Tear Film VEGF in Dogs with Vascularizing Corneal Disease. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/23166

Chicago Manual of Style (16^th Edition):

Brantman, Karen Renee. “Tear Film VEGF in Dogs with Vascularizing Corneal Disease.” 2013. Masters Thesis, Virginia Tech. Accessed February 27, 2021. http://hdl.handle.net/10919/23166.

MLA Handbook (7^th Edition):

Brantman, Karen Renee. “Tear Film VEGF in Dogs with Vascularizing Corneal Disease.” 2013. Web. 27 Feb 2021.

Vancouver:

Brantman KR. Tear Film VEGF in Dogs with Vascularizing Corneal Disease. [Internet] [Masters thesis]. Virginia Tech; 2013. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10919/23166.

Council of Science Editors:

Brantman KR. Tear Film VEGF in Dogs with Vascularizing Corneal Disease. [Masters Thesis]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/23166

University of New South Wales

5. Rohit, Athira. Effect of tear film lipid parameters in contact lens wear comfort.

Degree: Optometry & Vision Science, 2015, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/54317 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:34779/SOURCE02?view=true

► This thesis aimed to assess the effect of exogenous lipid supplements on ocular comfort during contact lens wear and the biology underpinning those effects. A… (more)

▼ This thesis aimed to assess the effect of exogenous lipid supplements on ocular comfort during contact lens wear and the biology underpinning those effects. A reliable device to measure the tear evaporation rate was developed and validated. Tear collection methods were optimised to characterise the tear lipidome. Electro spray tandem mass spectrometry was used to analyse individual lipid components. A pilot study demonstrated that the tear film stability during short-term contact lens wear was associated with ocular comfort, the activity of phospholipase A2 enzyme (sPLA2) and the concentrations of a lipid aldehyde, malondialdehyde (MDA). After 6-8 hours of lens wear, as the tear film stability increased so did the mole% of wax esters in the total lipidome whereas the mole% of cholesterol esters decreased. Higher tear evaporation rates were associated with reduced levels of phospholipids. The study also provided preliminary evidence for the effectiveness of an exogenous lipid supplement in improving ocular comfort and tear film stability during short-term contact lens wear. In the light of these preliminary findings, a double-masked, randomised crossover placebo controlled intervention study was conducted among habitual contact lens wearers to investigate various aspects of the lipid layer following the administration of two formulations of tear lipid supplements and their respective vehicle placebo. A transient improvement in tear film stability with the two lipid supplements was observed in symptomatic contact lens wearers. However, the improvement did not persist by the end of 2-week long lens wear. Between the two supplements, the anionic phospholipid emulsion drop showed a superior effect in ocular comfort, lipid layer appearance and tear evaporation rate in symptomatic wearers compared to the zwitterionic phospholipid spray. Improved contact lens wear comfort was related to increased tear film stability and lipid layer thickness, and a reduced tear evaporation rate, sPLA2 concentration and activity in tears. Increased concentration of sPLA2 was also associated with higher concentrations of degraded phospholipids and reduced levels of (O-acyl)-ω-hydroxy fatty acids in tears. The study found significant associations between various aspects of the lipid layer and comfort of the eye. These associations suggests that alterations in lipid biochemistry might be modulating changes in clinical and functional aspects of lipid layer which triggers changes in lens wear comfort. The learnings may help to inform development of topical preparations to improve comfort. Thus, the thesis provided an evidence based assessment of the effect of topical lipid preparations on ocular comfort by a comprehensive exploration of the clinical, functional and biochemical aspects of tear lipid layer. Advisors/Committee Members: Stapleton, Fiona, Optometry & Vision Science, Faculty of Science, UNSW, Willcox, Mark, Optometry & Vision Science, Faculty of Science, UNSW.

Subjects/Keywords: Tear film; Lipid layer; contact lens comfort

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rohit, A. (2015). Effect of tear film lipid parameters in contact lens wear comfort. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/54317 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:34779/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Rohit, Athira. “Effect of tear film lipid parameters in contact lens wear comfort.” 2015. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2021. http://handle.unsw.edu.au/1959.4/54317 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:34779/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Rohit, Athira. “Effect of tear film lipid parameters in contact lens wear comfort.” 2015. Web. 27 Feb 2021.

Vancouver:

Rohit A. Effect of tear film lipid parameters in contact lens wear comfort. [Internet] [Doctoral dissertation]. University of New South Wales; 2015. [cited 2021 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/54317 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:34779/SOURCE02?view=true.

Council of Science Editors:

Rohit A. Effect of tear film lipid parameters in contact lens wear comfort. [Doctoral Dissertation]. University of New South Wales; 2015. Available from: http://handle.unsw.edu.au/1959.4/54317 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:34779/SOURCE02?view=true

Queensland University of Technology

6. Alonso-Caneiro, David. Non-invasive assessment of tear film surface quality.

Degree: 2010, Queensland University of Technology

URL: https://eprints.qut.edu.au/41737/

► The tear film plays an important role preserving the health of the ocular surface and maintaining the optimal refractive power of the cornea. Moreover dry… (more)

Subjects/Keywords: tear film, image processing, pattern analysis, high-speed videokeratoscopy, data modelling, tear film surface kinetics, non-invasive methods; ODTA

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Alonso-Caneiro, D. (2010). Non-invasive assessment of tear film surface quality. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/41737/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Alonso-Caneiro, David. “Non-invasive assessment of tear film surface quality.” 2010. Thesis, Queensland University of Technology. Accessed February 27, 2021. https://eprints.qut.edu.au/41737/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Alonso-Caneiro, David. “Non-invasive assessment of tear film surface quality.” 2010. Web. 27 Feb 2021.

Vancouver:

Alonso-Caneiro D. Non-invasive assessment of tear film surface quality. [Internet] [Thesis]. Queensland University of Technology; 2010. [cited 2021 Feb 27]. Available from: https://eprints.qut.edu.au/41737/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Alonso-Caneiro D. Non-invasive assessment of tear film surface quality. [Thesis]. Queensland University of Technology; 2010. Available from: https://eprints.qut.edu.au/41737/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Rochester

7. Zhang, Aizhong. Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry.

Degree: PhD, 2017, University of Rochester

URL: http://hdl.handle.net/1802/33008

► Visual acuity and comfort is strongly influenced by the homogeneity and integrity of the ocular tear film. The tear film is established with each blink… (more)

▼ Visual acuity and comfort is strongly influenced by the homogeneity and integrity of the ocular tear film. The tear film is established with each blink and after a period of time it will break, leading to a loss of visual acuity and comfort to stimulate another blink. Chronic disorders of tear film lead to a prevalent problem of dry eye syndrome. The goal of my research is to develop objective and quantitative tools for dry eye syndrome diagnosis. The tear film health is directly associated with the environmental conditions such as temperature, humidity and air flow rate. Using thermography, I investigated the relation of the dynamic ocular surface temperature with the environment, and analyzed normal and dry eye subjects and different subgroups of dry eye subjects. I developed a thermal impulse perturbation (TIP) model to describe the fast heating of the ocular surface during each blink by the eyelids and redistributed tears. I studied the bioheat transfer mechanisms of the ocular surface cooling after a blink and experimentally measured the evaporation and convection coefficients in both normal and stressed clinical environments. Furthermore, I developed a second generation (2G) tearscope, using macroscopic imaging ellipsometry (MIE) that can simultaneously measure the thickness and refractive index of a film covering a flat or curved substrate. MIE was tested and validated with bare BK7 and SF11 substrates, MgF2 anti-reflection coated and Al2O3 coated BK7 substrates with curvatures approximating the human cornea. I also tested the flat witness samples on microscope slides and Si wafers, from the same coating runs with the curved coated samples. The final results were compared with the flat witness sample results from the profilometer, the J.A. Woollam Alpha SE ellipsometer, and the Filmetrics reflectometer. The thicknesses accuracy of the MIE is ±15 nm and the refractive index accuracy is ±0.05. The relaxed sample alignment tolerance is ±10 mm laterally in the focal plane, and ±2.5 mm axially. With further development, MIE has the potential to provide simultaneous measurements of lipid layer thicknesses and refractive indices, which may provide better clinical diagnosis of dry eye syndrome.

Subjects/Keywords: Ocular surface; Dry eye; Tear film; Thermography; Ellipsometry.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, A. (2017). Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/33008

Chicago Manual of Style (16^th Edition):

Zhang, Aizhong. “Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry.” 2017. Doctoral Dissertation, University of Rochester. Accessed February 27, 2021. http://hdl.handle.net/1802/33008.

MLA Handbook (7^th Edition):

Zhang, Aizhong. “Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry.” 2017. Web. 27 Feb 2021.

Vancouver:

Zhang A. Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry. [Internet] [Doctoral dissertation]. University of Rochester; 2017. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1802/33008.

Council of Science Editors:

Zhang A. Dynamic characterization of ocular surface with thermography and macroscopic imaging ellipsometry. [Doctoral Dissertation]. University of Rochester; 2017. Available from: http://hdl.handle.net/1802/33008

University of Illinois – Chicago

8. Ellis, Matthew. Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses.

Degree: 2014, University of Illinois – Chicago

URL: http://hdl.handle.net/10027/19023

► Glaucoma is a progressive neurodegenerative disorder in which ocular stressors adversely affect retinal ganglion cells, causing dendritic and axonal atrophies that eventually lead to cell… (more)

▼ Glaucoma is a progressive neurodegenerative disorder in which ocular stressors adversely affect retinal ganglion cells, causing dendritic and axonal atrophies that eventually lead to cell death and irreversible loss of vision. It is estimated that by the year 2020 the disease will affect more than 80 million individuals worldwide. Thus the effective management of glaucoma represents a critical, unmet medical need. Toward this end, the irreversible nature of glaucomatous vision loss dictates that the disease must be detected early in its progression if the efficacy of treatment plans is to be maximized. However, the early detection of glaucoma remains a difficult task. To overcome this challenge, the novel technology behind multi-electrode electroretinography has been developed by Dr. John Hetling of the University of Illinois at Chicago. This novel approach to elecroretinography uses a Contact Lens Electrode Array (CLEAr Lens™) to record spatially distinct bioelectric potentials from the cornea. These biopotentials are then used to interpret the health of the retina. It is hypothesized and supported by early data that via this approach, spatially localized functional deficits, such as those associated with glaucoma, can be detected at early stages of disease progression. The technique of multi-electrode electroretinography is dependent upon the recorded corneal potentials being spatially distinct. That is, the signals must preserve unique information about the underlying source currents generated by retinal activity. However, such information is lost if the signals are shunted together, which may occur if tear film between the cornea and recording lens is too thick. This places particular importance upon the thickness of this tear film with respect to the multi-electrode electroretinogram (meERG) project. Thus, this Thesis will be focused upon studying the dynamics of the tear film thickness beneath the CLEAr Lens. Through measuring tear film thickness in the ~20 minutes that follow lens insertion, we seek to investigate how tear film thickness affects meERG recording. We hypothesize that following lens insertion, there is a lens-settling period over which tear film thickness changes. Furthermore, we hypothesize that these changes in tear film thickness will induce predictable alterations in meERG responses. To examine these hypotheses, the current study seeks to determine how tear film thickness changes over the course of the lens settling period, and how these changes are manifested in meERG responses. Advisors/Committee Members: Hetling, John R. (advisor), McMahon, Timothy (committee member), Esmailbeigi, Hananeh (committee member).

Subjects/Keywords: Multi-electrode electroretinography; meERG; electroretinography; ERG; tear film; retina

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APA (6^th Edition):

Ellis, M. (2014). Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/19023

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ellis, Matthew. “Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses.” 2014. Thesis, University of Illinois – Chicago. Accessed February 27, 2021. http://hdl.handle.net/10027/19023.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ellis, Matthew. “Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses.” 2014. Web. 27 Feb 2021.

Vancouver:

Ellis M. Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses. [Internet] [Thesis]. University of Illinois – Chicago; 2014. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10027/19023.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ellis M. Tear Film Thickness and its Effects on the Recording of Multi-electrode Electroretinographic Responses. [Thesis]. University of Illinois – Chicago; 2014. Available from: http://hdl.handle.net/10027/19023

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Delaware

9. Zhong, Lan. Dynamics and imaging for lipid-layer-driven tear film breakup (TBU).

Degree: PhD, University of Delaware, Department of Mathematical Sciences, 2018, University of Delaware

URL: http://udspace.udel.edu/handle/19716/23959

► Rapid tear film thinning has been frequently observed in vivo. The tear film can thin dramatically within one second. However, the dominant mechanisms are unknown.… (more)

▼ Rapid tear film thinning has been frequently observed in vivo. The tear film can thin dramatically within one second. However, the dominant mechanisms are unknown. There are different arguments why rapid tear film thinning occurs. In this dissertation, we hypothesized that a non-uniform lipid layer drives tear film thinning; thicker lipid (glob) spreads to its surrounding thinner region, which induces a strong tangential flow and thins the aqueous layer. To test this hypothesis, we built lipid-driven thin film models using lubrication theory. The models successfully captured a very strong tangential flow as well as the short time scale. One successful prediction is that tear film breakup (TBU) occurs beneath a small glob and around the edge of a large glob; these match well with in vivo experimental results. ☐ We then adapted our lipid-driven model by adding equations for solute (salt ions and fluorescein) transport to investigate osmolarity and fluorescein concentration distribution. In rapid thinning, osmolarity and fluorescein concentration remains approximately constant. With the computed fluorescein concentration and aqueous layer thickness, we estimated fluorescein intensity, which is often used to visualize the tear thinning in clinical settings. Fluorescein intensity is proportional to aqueous layer thickness if tear film breakup time (TBUT) is less than 4 seconds. For tear film breakup (TBU) longer than 4 seconds, an initial fluorescein concentration less than about 0.2% can capture rapid tear thinning accurately. We made a close comparison between our simulation results (predicted fluorescein intensity) with in vivo experimental results, and the simulation matches the time scale and physical dimensions very well. ☐ Evaporation has been believed to be a major mechanism of TBU that develops over long times; our mathematical models in this thesis showed that the lipid layer can play an essential role in rapid TBU. This additional understanding of TBU provides insights about better imaging methods and treatment of lipid-driven TBU. ☐ To date, processing experimental images has been a very labor intense task. Thousands of high resolution microscopic images of the lipid layers of several thousand subjects were taken by a research group from The Ohio State University to study lipid layer structure. However, most of these images share limited and similar patterns. To better analyze these images, we built a classification model under the framework of Bag of Features using a small portion of the whole dataset. The classification model is then utilized to classify the remaining images. The model achieved an accuracy of 0.82 on the test dataset and highly reduced the workload of analyzing lipid layer images. Advisors/Committee Members: Braun, Richard J..

Subjects/Keywords: Pure sciences; Applied sciences; Tear film breakup (TBU)

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APA (6^th Edition):

Zhong, L. (2018). Dynamics and imaging for lipid-layer-driven tear film breakup (TBU). (Doctoral Dissertation). University of Delaware. Retrieved from http://udspace.udel.edu/handle/19716/23959

Chicago Manual of Style (16^th Edition):

Zhong, Lan. “Dynamics and imaging for lipid-layer-driven tear film breakup (TBU).” 2018. Doctoral Dissertation, University of Delaware. Accessed February 27, 2021. http://udspace.udel.edu/handle/19716/23959.

MLA Handbook (7^th Edition):

Zhong, Lan. “Dynamics and imaging for lipid-layer-driven tear film breakup (TBU).” 2018. Web. 27 Feb 2021.

Vancouver:

Zhong L. Dynamics and imaging for lipid-layer-driven tear film breakup (TBU). [Internet] [Doctoral dissertation]. University of Delaware; 2018. [cited 2021 Feb 27]. Available from: http://udspace.udel.edu/handle/19716/23959.

Council of Science Editors:

Zhong L. Dynamics and imaging for lipid-layer-driven tear film breakup (TBU). [Doctoral Dissertation]. University of Delaware; 2018. Available from: http://udspace.udel.edu/handle/19716/23959

10. Athukorala, Bhagya. Mathematical modeling of a contact lens and tear layer at equilibrium.

Degree: 2012, Texas Tech University

URL: http://hdl.handle.net/2346/46968

► In this thesis, we study the capillary surface at a vertical wall, and a tear meniscus around a symmetric, spherical cap lens. We propose a… (more)

Subjects/Keywords: Contact lens; tear film

…lens resting on the inside of the lower eyelid . . . . . Case 1: Tear film over a disk… …meniscus. Since tear film is at equilibrium, its velocity is u and, hence, viscous stress τ 1 are… …tear film, upper and lower contact angles are calculated by considering the quasistatic… …posterior tear film completely neglects hydrostatic pressure variation due to gravity. But, our… …quasi-steady motion of the tear film under the contact lens and away from the lens. In the…

10 more images…

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APA (6^th Edition):

Athukorala, B. (2012). Mathematical modeling of a contact lens and tear layer at equilibrium. (Thesis). Texas Tech University. Retrieved from http://hdl.handle.net/2346/46968

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Athukorala, Bhagya. “Mathematical modeling of a contact lens and tear layer at equilibrium.” 2012. Thesis, Texas Tech University. Accessed February 27, 2021. http://hdl.handle.net/2346/46968.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Athukorala, Bhagya. “Mathematical modeling of a contact lens and tear layer at equilibrium.” 2012. Web. 27 Feb 2021.

Vancouver:

Athukorala B. Mathematical modeling of a contact lens and tear layer at equilibrium. [Internet] [Thesis]. Texas Tech University; 2012. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/2346/46968.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Athukorala B. Mathematical modeling of a contact lens and tear layer at equilibrium. [Thesis]. Texas Tech University; 2012. Available from: http://hdl.handle.net/2346/46968

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Milazzo, Enza Maria Serena. Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis.

Degree: 2012, Università degli Studi di Catania

URL: http://hdl.handle.net/10761/1176

► La Vernal Keratoconjunctivitis (VKC) è una patologia oculare allergica cronica che determina nei soggetti che ne soffrono un quadro infiammatorio severo. Lo scopo del presente… (more)

▼ La Vernal Keratoconjunctivitis (VKC) è una patologia oculare allergica cronica che determina nei soggetti che ne soffrono un quadro infiammatorio severo. Lo scopo del presente lavoro è stato quello di analizzare il profilo proteomico qualitativo e quantitativo del fluido lacrimale appartenente a soggetti affetti da VKC e di confrontarlo con quello di soggetti sani, in modo da stabilire differenze presenti nel loro pattern di espressione proteico. I campioni sono stati trattati tramite la tecnologia iTRAQ, seguita dall analisi dei campioni tramite 1D-LC-MALDI MS/MS. Durante la prima fase (biomarker discovery) sono stati realizzati cinque esperimenti iTRAQ 4-plex (due campioni di controllo e due patologici in ogni esperimento). I risultati ottenuti hanno permesso di individuare tre biomarkers della VKC: siero albumina, serotransferrina ed emopexina. Il rapporto 115/114 (rapporto quantitativo di una data proteina espressa nei due campioni di controllo) per queste tre proteine, infatti, è un numero vicino ad uno in tutti gli esperimenti effettuati; tutti i soggetti patologici presentano un notevole aumento nei livelli di tali proteine; la sovraespressione delle tre proteine sieriche, infine, è dello stesso ordine di grandezza nello stesso soggetto. Le analisi sui dieci pazienti affetti da VKC hanno evidenziato un incremento lineare del livello di siero albumina analizzando soggetti che presentavano la patologia con un diverso grado di severità (da lieve a grave). I risultati ottenuti, pertanto, possono essere utilizzati anche per individuare in maniera obiettiva il grado di severità della patologia. Durante la seconda fase è stata impiegata la tecnologia iTRAQ 8-plex (analisi simultanea di otto diversi soggetti) per valutare l efficacia di due trattamenti farmacologici, uno a base di ciclosporina A all 1% e l altro sull impiego di clobetasone, nella prevenzione delle ricadute ed il controllo delle fasi attive della patologia. Le lacrime di tutti i soggetti trattati con ciclosporina A e con clobetasone rispetto ai soggetti non sottoposti ad alcun trattamento presentavano una notevole diminuzione nei livelli delle proteine siero albumina, serotransferrina, ed emopexina ma anche di altre due proteine tipicamente sieriche non individuate negli altri esperimenti: apolipoprotein A-I e alpha 1-acid glycoprotein. I risultati, dunque, sono stati positivi per entrambi i trattamenti ed hanno confermato l efficacia di tali farmaci per la gestione delle fasi attive della patologia in quanto consentono un buon controllo dei sintomi della VKC ed in particolare del quadro infiammatorio.

Subjects/Keywords: Area 03 - Scienze chimiche; Tear film; Vernal Keratoconjunctivitis; iTRAQ; Quantitative Proteomics

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APA (6^th Edition):

Milazzo, E. M. S. (2012). Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis. (Thesis). Università degli Studi di Catania. Retrieved from http://hdl.handle.net/10761/1176

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Milazzo, Enza Maria Serena. “Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis.” 2012. Thesis, Università degli Studi di Catania. Accessed February 27, 2021. http://hdl.handle.net/10761/1176.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Milazzo, Enza Maria Serena. “Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis.” 2012. Web. 27 Feb 2021.

Vancouver:

Milazzo EMS. Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis. [Internet] [Thesis]. Università degli Studi di Catania; 2012. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10761/1176.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Milazzo EMS. Analisi proteomica quantitativa del fluido lacrimale per la diagnosi e la terapia farmacologica della Vernal Keratoconjunctivitis. [Thesis]. Università degli Studi di Catania; 2012. Available from: http://hdl.handle.net/10761/1176

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

12. Alghamdi, Waleed. Impact of contact lens wear on the meibomian glands, lid margin and tear film.

Degree: Optometry & Vision Science, 2016, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/56872 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41811/SOURCE02?view=true

► Ocular discomfort and dry eye symptoms are the main reasons for contact lens (CL) wear intolerance and discontinuation. In this context, dry eye and discomfort… (more)

▼ Ocular discomfort and dry eye symptoms are the main reasons for contact lens (CL) wear intolerance and discontinuation. In this context, dry eye and discomfort can be multifactorial, but with a growing clinical impression that physiological changes in the eyelid and meibomian glands (MGs) are involved. Yet, evidence is still inconclusive on the impact of CL wear on MGs and lid margin disease. Thus, this thesis aimed to observe the characteristics of the MGs, eyelids and tear film following varying durations of CL wear or previous CL wear. This thesis consists of three main studies that are clinical, histological and biochemical in nature.In order to achieve this aim, a cross-sectional study was conducted involving a single observation of each member of a sample divided into five groups based on soft contact lens wearing experience. Three groups were existing CL wearers with different exposure durations (short, medium and long); one group had previously worn CLs and had now ceased; and a control group who had never worn CLs. In the clinical study, a series of tests was applied to assess changes in the morphology and function of MGs, lid margin abnormalities, symptoms and related dry eye and ocular surface damage. Alterations to MG morphology and function, poorer tear film stability and lid margin characteristics were found to be associated with CL wear. Although these changes onset during the first two years of wear, prolonged CL exposure beyond this point does not appear to be associated with further modification. Cessation of wear for at least 6 months does not lead to resolution.Following on from these observations a histological study was conducted to investigate the nature of cellular changes in the lid margin epithelium using the impression cytology technique. Histochemical analysis showed that CL wear altered lid margin epithelial cell morphology, cytoplasmic: nuclear ratio and goblet cell density but evidence for increased keratinisation was inconclusive. Next, biochemical studies examined two areas, first changes in the levels of inflammatory mediator MMP-9 in tears and second, the composition of meibum in the context of CL wear. The level of MMP-9 was relatively higher in early years of CL wear whereas meibum composition analysis did not reveal any specific changes with CL wear. Advisors/Committee Members: Papas, Eric, Optometry & Vision Science, Faculty of Science, UNSW, Markoulli, Maria, Optometry & Vision Science, Faculty of Science, UNSW, Holden, Brien, Optometry & Vision Science, Faculty of Science, UNSW.

Subjects/Keywords: Contact lens; Meibomian glands; Dry eye; Lid margin; Tear film

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APA (6^th Edition):

Alghamdi, W. (2016). Impact of contact lens wear on the meibomian glands, lid margin and tear film. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/56872 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41811/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Alghamdi, Waleed. “Impact of contact lens wear on the meibomian glands, lid margin and tear film.” 2016. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2021. http://handle.unsw.edu.au/1959.4/56872 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41811/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Alghamdi, Waleed. “Impact of contact lens wear on the meibomian glands, lid margin and tear film.” 2016. Web. 27 Feb 2021.

Vancouver:

Alghamdi W. Impact of contact lens wear on the meibomian glands, lid margin and tear film. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2021 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/56872 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41811/SOURCE02?view=true.

Council of Science Editors:

Alghamdi W. Impact of contact lens wear on the meibomian glands, lid margin and tear film. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/56872 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:41811/SOURCE02?view=true

Iowa State University

13. Sebbag, Lionel. An eye on the dog as a translational model for ocular pharmacology.

Degree: 2020, Iowa State University

URL: https://lib.dr.iastate.edu/etd/18223

► Today’s high failure rate in ophthalmic clinical trials can be largely explained by two major shortcomings: (i) the animals routinely studied (rabbits, mice, rats) are… (more)

▼ Today’s high failure rate in ophthalmic clinical trials can be largely explained by two major shortcomings: (i) the animals routinely studied (rabbits, mice, rats) are not representative of the affected population due to apparent anatomical and physiological differences with humans; and (ii) studies conducted in healthy eyes do not account for physiological disturbances in ocular homeostasis present in diseased eyes. Unlike traditional laboratory animals, diseases in dogs better reflect the complex genetic, environmental, and physiological variation present in humans; however, the translational potential of canine research is currently limited by scarce information on normative data specific to dogs, and the limited means to mimic ocular disease in a reliable and non-invasive manner in this species. The work conducted in the dissertation provides a deeper understanding of the canine ocular surface in health and disease states, investigating laboratory Beagle dogs and canine patients of varied breeds and cephalic conformations. Tear fluid was collected from canine eyes in successive experiments – primarily via Schirmer tear strips but also capillary glass tubes and absorbent sponges – and subsequent bioanalytical tools included fluorophotometry (tear film fluorescence), infrared spectroscopy (total protein content), immunoassays (serum albumin, cytokines, chemokines) and liquid chromatography-mass spectrometry (corticosteroids). Data analysis combined conventional statistical tests with nonlinear mixed-effects mathematical modeling to improve the robustness of the predictions. The main research outcomes of the dissertation work are the following: (i) Normative data were established for canine tear film dynamics, including tear volume (65.3 µL), basal tear turnover rate (12.2%/min) and reflex tear turnover rate (50%/min). In both clinical and research settings, successive lacrimal tests should be spaced by ≥ 10 min in dogs to provide sufficient time for the tear film to replenish. (ii) The volumetric capacity of the canine palpebral fissure was 31.3 µL, approximating the volume of a single eyedrop. Kinetic studies confirmed that a single drop is sufficient for topical administration in dogs, any excess being lost predominantly by blinking and spillage over the periocular skin. (iii) Topical histamine solutions of 1, 10, and 375 mg/mL induced mild, moderate, and severe conjunctivitis in dogs, respectively. The resulting disruption of the blood-tear barrier promoted leakage of plasma compounds (eg., albumin) into the tear film, a finding confirmed in dogs with naturally acquired ocular diseases. This ‘large animal’ model was robust, non-invasive, and self-resolving, providing a unique opportunity to investigate the ocular surface in health and disease. (iv) Acute conjunctivitis increased tear quantity and decreases tear stability, although ocular surface homeostasis was rapidly restored. (v) Corticosteroid levels in the tear film did not change significantly between healthy vs. diseased eyes following oral prednisone…

Subjects/Keywords: Albumin; Animal models; Ocular Surface; Pharmacology; Tear film; Translational Research

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sebbag, L. (2020). An eye on the dog as a translational model for ocular pharmacology. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/18223

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sebbag, Lionel. “An eye on the dog as a translational model for ocular pharmacology.” 2020. Thesis, Iowa State University. Accessed February 27, 2021. https://lib.dr.iastate.edu/etd/18223.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sebbag, Lionel. “An eye on the dog as a translational model for ocular pharmacology.” 2020. Web. 27 Feb 2021.

Vancouver:

Sebbag L. An eye on the dog as a translational model for ocular pharmacology. [Internet] [Thesis]. Iowa State University; 2020. [cited 2021 Feb 27]. Available from: https://lib.dr.iastate.edu/etd/18223.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sebbag L. An eye on the dog as a translational model for ocular pharmacology. [Thesis]. Iowa State University; 2020. Available from: https://lib.dr.iastate.edu/etd/18223

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Plymouth

14. Abdul Rahim, Muhammad Afzam Shah Bin. An investigation of computer vision syndrome with smart devices.

Degree: PhD, 2018, University of Plymouth

URL: http://hdl.handle.net/10026.1/12813

► The overarching theme of the thesis was to investigate the association between smart device use and computer vision syndrome. The initial study designed and developed… (more)

▼ The overarching theme of the thesis was to investigate the association between smart device use and computer vision syndrome. The initial study designed and developed the Open Field Tear film Analyser (OFTA) enabling a continuous, real-time assessment of the tear film and blink characteristics during smart device use. The monocular OFTA prototype was validated and showed good intra- and inter-observer repeatability relative to the Oculus Keratograph 5M and Bausch and Lomb one position keratometer. Subsequently, tear osmolarity following engagement with reading and gaming tasks on smart device and paper platforms was investigated. Discrete measures of osmolarity pre- and post-engagement with the tasks were obtained with the TearLab osmometer; osmolarity values differed between platforms when participants were engaged in a gaming task but no such difference was observed with the reading task. In addition, the influence of repeated measurements on tear osmolarity was also explored. To simulate the habitual binocular viewing conditions normally associated with smart device use, the binocular OFTA was developed. The device was used to assess the tear film and blink characteristics whilst engaging with reading and gaming tasks on smart device and paper platforms. The results revealed differences in blink characteristics and non-invasive tear break up time between the different platforms and tasks assessed. In addition, the thesis also reports on an investigation examining the real-time accommodative response to various targets displayed on smart devices using an open-field autorefractor with a Badal lens system adaptation. The results showed that accommodative latency, accommodative lag, mean velocity of accommodation, speed of disaccommodation and mean velocity of disaccommodation varied across the different platforms. Through the use of validated subjective questionnaires and smartphone apps, the relationship between duration of smartphone use and symptoms of dry eye were examined. The findings of this study demonstrated that longer duration of smartphone and personal computer use were associated with higher risk of dry eyes as indicated by subjective questionnaire outcomes.

Subjects/Keywords: 617.7; Non invasive tear break up time; Binocular Open Field Tear Film Analyzer; Tear osmolarity; Accommodation response; Smartphone usage pattern; Smart devices and Computer Vision Syndrome

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Abdul Rahim, M. A. S. B. (2018). An investigation of computer vision syndrome with smart devices. (Doctoral Dissertation). University of Plymouth. Retrieved from http://hdl.handle.net/10026.1/12813

Chicago Manual of Style (16^th Edition):

Abdul Rahim, Muhammad Afzam Shah Bin. “An investigation of computer vision syndrome with smart devices.” 2018. Doctoral Dissertation, University of Plymouth. Accessed February 27, 2021. http://hdl.handle.net/10026.1/12813.

MLA Handbook (7^th Edition):

Abdul Rahim, Muhammad Afzam Shah Bin. “An investigation of computer vision syndrome with smart devices.” 2018. Web. 27 Feb 2021.

Vancouver:

Abdul Rahim MASB. An investigation of computer vision syndrome with smart devices. [Internet] [Doctoral dissertation]. University of Plymouth; 2018. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10026.1/12813.

Council of Science Editors:

Abdul Rahim MASB. An investigation of computer vision syndrome with smart devices. [Doctoral Dissertation]. University of Plymouth; 2018. Available from: http://hdl.handle.net/10026.1/12813

Queensland University of Technology

15. 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 (6^th 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 (16^th Edition):

Tyagi, Garima. “Ocular surface changes with short-term contact lens wear.” 2011. Thesis, Queensland University of Technology. Accessed February 27, 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 (7^th Edition):

Tyagi, Garima. “Ocular surface changes with short-term contact lens wear.” 2011. Web. 27 Feb 2021.

Vancouver:

Tyagi G. Ocular surface changes with short-term contact lens wear. [Internet] [Thesis]. Queensland University of Technology; 2011. [cited 2021 Feb 27]. 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

University of Arizona

16. 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)

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 (6^th 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 (16^th Edition):

Solem, Cameron Cole. “Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography .” 2017. Masters Thesis, University of Arizona. Accessed February 27, 2021. http://hdl.handle.net/10150/624129.

MLA Handbook (7^th Edition):

Solem, Cameron Cole. “Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography .” 2017. Web. 27 Feb 2021.

Vancouver:

Solem CC. Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography . [Internet] [Masters thesis]. University of Arizona; 2017. [cited 2021 Feb 27]. 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

17. 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 (6^th 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 (16^th Edition):

Micali, Jason Daniel. “Interferometer for Measuring Dynamic Corneal Topography .” 2015. Doctoral Dissertation, University of Arizona. Accessed February 27, 2021. http://hdl.handle.net/10150/581129.

MLA Handbook (7^th Edition):

Micali, Jason Daniel. “Interferometer for Measuring Dynamic Corneal Topography .” 2015. Web. 27 Feb 2021.

Vancouver:

Micali JD. Interferometer for Measuring Dynamic Corneal Topography . [Internet] [Doctoral dissertation]. University of Arizona; 2015. [cited 2021 Feb 27]. 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

18. 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 (6^th 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 (16^th Edition):

Primeau, Brian Christopher. “INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS .” 2011. Doctoral Dissertation, University of Arizona. Accessed February 27, 2021. http://hdl.handle.net/10150/202971.

MLA Handbook (7^th Edition):

Primeau, Brian Christopher. “INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS .” 2011. Web. 27 Feb 2021.

Vancouver:

Primeau BC. INTERFEROMETRIC CHARACTERIZATION OF TEAR FILM DYNAMICS . [Internet] [Doctoral dissertation]. University of Arizona; 2011. [cited 2021 Feb 27]. 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

Virginia Tech

19. Rainbow, Marc E. Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses.

Degree: MS, Veterinary Medical Sciences, 2004, Virginia Tech

URL: http://hdl.handle.net/10919/9896

► The purpose of this study was to determine the effects of three medical treatments, topical oxytetracycline, topical prednisolone acetate, and systemic flunixin meglumine, on the… (more)

▼ The purpose of this study was to determine the effects of three medical treatments, topical oxytetracycline, topical prednisolone acetate, and systemic flunixin meglumine, on the activity of two proteinases, matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), in equine tear film. The study design consisted of twelve ophthalmically normal horses separated into three groups of four in a cross-over study design. Each group was treated for 5 days with flunixin meglumine (500mg IM bid), topical 1% prednisolone acetate (0.2ml tid), or topical oxytetracycline (0.2ml tid), followed by a 9-day washout period. All topical medications were applied to the left eye and the right eye was treated with a placebo. Tears were collected before the first treatment on day one and the morning following the last treatment on day 5. Tear film proteinase activity was measured using gelatin zymography and measurements of optical density. Statistical analysis of the difference between the treated and untreated eyes and the eyes before and after treatment was performed using mixed effects model for ANOVA. When eyes were compared after treatment, there was no significant difference between treated and placebo eyes for MMP-2 or MMP-9 for any of the treatments. When post-treated eyes were compared to pre-treated eyes, there was a significant decrease in MMP-2 activity in the left eye of horses treated with flunixin meglumine (P=0.0259). There were no differences in MMP-2 and MMP-9 activity for the other treatments. In conclusion, topical 1% prednisolone acetate and topical oxytetracycline did not significantly change MMP-2 or MMP-9 activity in normal equine tear film. Systemic flunixin meglumine had an inhibitory, but questionable, effect on MMP-2 activity in normal equine tear film. This project was funded by Patricia Bonsall Stuart Award for Equine Research. Advisors/Committee Members: Pickett, J. Phillip (committeechair), Brooks, Dennis E. (committee member), Herring, Ian P. (committee member), Dascanio, John J. (committee member).

Subjects/Keywords: tear film; cornea; equine; matrix matalloproteinase

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APA (6^th Edition):

Rainbow, M. E. (2004). Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/9896

Chicago Manual of Style (16^th Edition):

Rainbow, Marc E. “Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses.” 2004. Masters Thesis, Virginia Tech. Accessed February 27, 2021. http://hdl.handle.net/10919/9896.

MLA Handbook (7^th Edition):

Rainbow, Marc E. “Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses.” 2004. Web. 27 Feb 2021.

Vancouver:

Rainbow ME. Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses. [Internet] [Masters thesis]. Virginia Tech; 2004. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10919/9896.

Council of Science Editors:

Rainbow ME. Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses. [Masters Thesis]. Virginia Tech; 2004. Available from: http://hdl.handle.net/10919/9896

The Ohio State University

20. Kimball, Samuel H. Evaporation is the Primary Mechanism of Tear Film Thinning.

Degree: MS, Vision Science, 2009, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957487

► The purpose of this study was to determine the contribution of evaporation in the thinning of the pre-corneal tear film. The human tear film is… (more)

Subjects/Keywords: Ophthalmology; tear film; dry eye; evaporation; tear film thinning; interferometry; mechanisms of tear film thinning

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APA (6^th Edition):

Kimball, S. H. (2009). Evaporation is the Primary Mechanism of Tear Film Thinning. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957487

Chicago Manual of Style (16^th Edition):

Kimball, Samuel H. “Evaporation is the Primary Mechanism of Tear Film Thinning.” 2009. Masters Thesis, The Ohio State University. Accessed February 27, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957487.

MLA Handbook (7^th Edition):

Kimball, Samuel H. “Evaporation is the Primary Mechanism of Tear Film Thinning.” 2009. Web. 27 Feb 2021.

Vancouver:

Kimball SH. Evaporation is the Primary Mechanism of Tear Film Thinning. [Internet] [Masters thesis]. The Ohio State University; 2009. [cited 2021 Feb 27]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957487.

Council of Science Editors:

Kimball SH. Evaporation is the Primary Mechanism of Tear Film Thinning. [Masters Thesis]. The Ohio State University; 2009. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957487

University of Waterloo

21. Walther, Hendrik. Contact Lenses and Tear Film Lipids.

Degree: 2017, University of Waterloo

URL: http://hdl.handle.net/10012/12767

► Introduction Lipids are essential tear components that aid the stability of the tear film (TF) to protect it from excess evaporation. The composition, conformation, and… (more)

▼ Introduction Lipids are essential tear components that aid the stability of the tear film (TF) to protect it from excess evaporation. The composition, conformation, and function of TF lipids are jeopardized by external factors such as contact lens (CL) wear and environmental elements (i.e. UV radiation, oxidation). Specifically, silicone hydrogel (SiHy) CLs exhibit relatively high deposition of TF lipids that may be associated with visual disturbances and discomfort. Additionally, lipids are degraded by oxidation and may cause alterations of the TF lipid layer, which in turn might be a source for dry eye symptoms. The overall goal of this thesis was to evaluate the quantity and location of lipid deposition on various CL materials over time and also to assess the impact lipid contamination may have on various care products and TF quality measurements. The specific aims of each chapter of this thesis were as follows: • Chapter 3: To determine the efficacy of multi-purpose solutions (MPS) on the removal of cholesterol deposits from SiHy lens materials. • Chapter 4: To analyze the uptake of cholesterol on SiHy and conventional hydrogel (CH) daily disposable (DD) CL materials using an in vitro radiochemical detection method. • Chapter 5: To evaluate the differences in lipid uptake and penetration in DD CL using the conventional “in-vial” method compared to a novel in vitro eye model. • Chapter 6: To develop a novel in vitro model to determine pre-lens non-invasive break- up times (NIBUT) and to subsequently compare the break-up times over five contemporary DD lens materials. • Chapter 7: To optimize and develop a method to determine and quantify lipid peroxidation by-products that indicates oxidative stress in tears. Materials and Methods • Chapter 3: Five contemporary SiHy lens materials were incubated for 7 days using a radiochemical experiment. Additionally, lenses were stored and cleaned in different MPSs using a rub and rinse technique. Lipids were then extracted from lenses with 2:1 chloroform:methanol, analyzed in a beta-particle radiation counter and μg/lens of cholesterol was determined. • Chapter 4: Seven different commercially available DD CLs were incubated for 16 hours to determine the impact of material composition on cholesterol deposition. Subsequent to the incubation, lenses were extracted using 2:1 chloroform:methanol and the extracts were analyzed in a beta-particle radiation counter and (ng/lens) extrapolated from standard curves. • Chapter 5: Seven DD CLs were incubated for 4 and 12 hours in an artificial tear solution (ATS) containing fluorescently-labelled cholesterol (7-nitrobenz-2-oxa-1,3-diazol-4- yl-cholesterol, or NBD-cholesterol). Additionally, CLs were incubated in an “in-vial” condition and compared to a novel in vitro eye platform, designed to simulate physiological tear flow, tear volume, and ‘simulated’ blinking. After the incubation period, the CLs were analyzed using a laser scanning confocal microscope (LSCM), and quantitative analyses for penetration depth and…

Subjects/Keywords: contact lenses; tear film lipids; lipid deposition; silicone hydrogels; conventional hydrogels; lipid penetration; lipid oxidation; daily disposable; non-invasive tear break-up time; oxidative stress; cholesterol

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APA (6^th Edition):

Walther, H. (2017). Contact Lenses and Tear Film Lipids. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/12767

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Walther, Hendrik. “Contact Lenses and Tear Film Lipids.” 2017. Thesis, University of Waterloo. Accessed February 27, 2021. http://hdl.handle.net/10012/12767.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Walther, Hendrik. “Contact Lenses and Tear Film Lipids.” 2017. Web. 27 Feb 2021.

Vancouver:

Walther H. Contact Lenses and Tear Film Lipids. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10012/12767.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Walther H. Contact Lenses and Tear Film Lipids. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/12767

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Minho

22. Oliveira, Cristina Daniela Moreira. Edema corneal com lentes esclerais .

Degree: 2013, Universidade do Minho

URL: http://hdl.handle.net/1822/28063

► Nos últimos cinco anos houve um aumento do uso de lentes esclerais rígidas permeáveis aos gases de grande diâmetro, uma vez que estas lentes são… (more)

Subjects/Keywords: Lentes esclerais; Edema corneal; Transmissibilidade ao oxigénio; Filme lacrimal pós-lente; Scleral lenses; Corneal edema; Oxygen transmissibility; Post- lens tear film

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APA (6^th Edition):

Oliveira, C. D. M. (2013). Edema corneal com lentes esclerais . (Masters Thesis). Universidade do Minho. Retrieved from http://hdl.handle.net/1822/28063

Chicago Manual of Style (16^th Edition):

Oliveira, Cristina Daniela Moreira. “Edema corneal com lentes esclerais .” 2013. Masters Thesis, Universidade do Minho. Accessed February 27, 2021. http://hdl.handle.net/1822/28063.

MLA Handbook (7^th Edition):

Oliveira, Cristina Daniela Moreira. “Edema corneal com lentes esclerais .” 2013. Web. 27 Feb 2021.

Vancouver:

Oliveira CDM. Edema corneal com lentes esclerais . [Internet] [Masters thesis]. Universidade do Minho; 2013. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1822/28063.

Council of Science Editors:

Oliveira CDM. Edema corneal com lentes esclerais . [Masters Thesis]. Universidade do Minho; 2013. Available from: http://hdl.handle.net/1822/28063

University of Rochester

23. Huang, Jinxin. Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics.

Degree: PhD, 2016, University of Rochester

URL: http://hdl.handle.net/1802/31696

► Dry Eye Disease (DED) is a common multifactorial disease that affects the ocular surface. Symptoms of DED include discomfort, visual disturbance, and irritation. In severe… (more)

▼ Dry Eye Disease (DED) is a common multifactorial disease that affects the ocular surface. Symptoms of DED include discomfort, visual disturbance, and irritation. In severe cases, damage to and scarring of the ocular surface can cause permanent vision loss. DED is recognized as one of the most frequent reasons for seeking eye care, and it seriously degrades the vision-related quality of life. </br> Tear film instability has been established as a core mechanism of DED. Traditionally, this has been quantified as the temporal thinning of the tear film thickness leading to tear film breakup. The normal tear film consists of three layers: the lipid layer, the aqueous layer, and the mucin layer. The lipid layer is about 20~150 nm thick; underneath the lipid lies the aqueous layer, which is secreted by the lacrimal gland and contributes the largest volume to the tear with a few microns in thickness. Because there is no clear interface between the aqueous and mucin components of the tear film, they are considered as one layer in this thesis. Also, the mucin component may be thought as creating a rough interface to the cornea. </br> Among different methods of measuring the tear film thickness in vivo, optical coherence tomography (OCT) was shown to be a promising approach, due to its noninvasive nature and the recent advance of broadband light source techniques. A few methods based on spectral domain OCT were explored: indirect measurement of the tear film thickness with the application of a contact lens, and direct thickness measurements with ultrahigh resolution OCT. However, these OCT methods measure the total thickness of the tear film and cannot separate the lipid layer and the aqueous layer. This thesis proposes an approach that is based on the combination of the spectral domain OCT hardware and statistical decision theory, to simultaneously measure the thicknesses of both the lipid and the aqueous layers of the tear film. </br> To develop a customized OCT system that is suitable for the tear film dynamics measurement application, a task-based assessment approach was used to explore the system parameters space of an OCT system. The idea of task-based assessment is to evaluate the system parameters with performance metrics that are associated with the specified task, which in this thesis is a thickness estimation task. The thickness estimation task was mathematically modeled, including the physical process of data acquisition with key parameters of the system taken into account as well as the data post-processing procedure with a thickness estimator. To investigate the impact of different parameters, accuracy and precision of the thickness estimates were used as performance metrics. The theoretical findings were later validated with physical phantoms. </br> With the success in the physical phantoms validation, the system was advanced to measure the tear film thickness and dynamics in vivo, which was approved by the Research Subjects Review Board at the University of Rochester. Results find that…

Subjects/Keywords: Maximum-likelihood estimation; Optical coherence tomography; Statistical noise; Task-based assessment; Tear film dynamics; Thickness estimation

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APA (6^th Edition):

Huang, J. (2016). Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/31696

Chicago Manual of Style (16^th Edition):

Huang, Jinxin. “Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics.” 2016. Doctoral Dissertation, University of Rochester. Accessed February 27, 2021. http://hdl.handle.net/1802/31696.

MLA Handbook (7^th Edition):

Huang, Jinxin. “Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics.” 2016. Web. 27 Feb 2021.

Vancouver:

Huang J. Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics. [Internet] [Doctoral dissertation]. University of Rochester; 2016. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1802/31696.

Council of Science Editors:

Huang J. Nanometer-class optical coherence tomography for in vivo imaging of the tear film dynamics. [Doctoral Dissertation]. University of Rochester; 2016. Available from: http://hdl.handle.net/1802/31696

McMaster University

24. Cui, Yuguo. Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components.

Degree: PhD, 2010, McMaster University

URL: http://hdl.handle.net/11375/19032

►

Hydroxypropyl guar (HPG) is an effective ingredient in lubricant eye drops used by patients with dry eye disease. The overall goal of the work… (more)

▼

Hydroxypropyl guar (HPG) is an effective ingredient in lubricant eye drops used by patients with dry eye disease. The overall goal of the work described in this thesis is to understand the physical-chemical properties of HPG in the presence ofmodel surfaces and solutes with view to understanding the behavior of HPG in the tear film. HPG behaviors are complex because borate ions bind to HPG, which converts nonionic HPG into anionic polyelectrolyte, RPG-borate. The borate binding constants are very low, meaning the charges on RPG-borate are labile. Another consequence ofweak binding is that the equilibrium electrolyte concentration with HPG-borate is relatively high. Mathematical models were developed to predict the structure of HPG-borate as functions of pH. This thesis probes the question "When does HPG-borate behave as an anionic polyelectrolyte?" This work shows that HPG-borate exhibits deviant behaviors of an anionic polyelectrolyte: does not interact with cationic surfactants below the CMC; does not interact with lysozyme (cationic protein), and does not adsorb onto cationic liposomes. By contrast, anionic polyelectrolytes such as carboxymethyl guar display generic behaviors. On the other hand, HPG-borate forms polyelectrolyte complexes with cationic polyelectrolytes at low ionic strength and other work from our laboratory has shown that HPG-borate flocculates cationic polystyrene latex. This complex range of RPG-borate behaviors was rationalized by proposing that the labile nature ofthe charge groups means that the charge density on RPG-borate is regulated by the local electrostatic environment. Near a cationic surface HPG-borate charge density increases whereas near an anionic surface the charge density is lower. Anionic liposome interactions with HPG-borate were characterized. HPG concentrations close to clinical levels induced depletion flocculation ofthe anionic liposomes. This is the first example we have found depletion interactions were proposed for the tear film. To summarize the main implications for the ophthalmic application of HPG are: 1) under ophthalmic conditions HPG-borate behaves as a nonionic water soluble polymer; 2) RPG-borate will adsorb onto hydrophobic domains but will not interact with lysozyme; 3) depletion interactions are important and have the potential to stabilize the lipid layer and destabilize emulsion droplets and other dispersed species in the tear film.

Thesis

Doctor of Philosophy (PhD)

Advisors/Committee Members: Pelton, Robert H., Chemical Engineering.

Subjects/Keywords: chemical engineering; hydroxypropyl guar; borate interaction; tear film component

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APA (6^th Edition):

Cui, Y. (2010). Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/19032

Chicago Manual of Style (16^th Edition):

Cui, Yuguo. “Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components.” 2010. Doctoral Dissertation, McMaster University. Accessed February 27, 2021. http://hdl.handle.net/11375/19032.

MLA Handbook (7^th Edition):

Cui, Yuguo. “Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components.” 2010. Web. 27 Feb 2021.

Vancouver:

Cui Y. Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components. [Internet] [Doctoral dissertation]. McMaster University; 2010. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/11375/19032.

Council of Science Editors:

Cui Y. Characterizing Hydroxypropyl Guar - Borate Interactions with Model Tear Film Components. [Doctoral Dissertation]. McMaster University; 2010. Available from: http://hdl.handle.net/11375/19032

McMaster University

25. Spadafora, Alysha. Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers.

Degree: MASc, 2017, McMaster University

URL: http://hdl.handle.net/11375/22798

► When a biomaterial is inserted into the body, the interaction of the surface with the surrounding biological environment is crucial. Given the importance of the… (more)

▼ When a biomaterial is inserted into the body, the interaction of the surface with the surrounding biological environment is crucial. Given the importance of the surface, the ability to alter the surface properties to support a compatible environment is therefore desirable. Silicone hydrogel contact lenses (CL) allow for improved oxygen permeability through the incorporation of siloxane functional groups. These groups however are extremely surface active and upon rotation, can impart hydrophobicity to the lens surface, decreasing lens wettability and increasing protein and lipid deposition. Lens biofouling may be problematic and therefore surface modification of these materials to increase compatibility is exceedingly recognized for importance in both industry and research. The current work focuses on the creation of a novel anti-fouling polymer surface by the incorporation of 2-methacryoyloxyethyl phosphorylcholine (MPC), well known for its biomimetic and anti-fouling properties. A controlled polymerization method was used to generate a unique double-grafted architecture to explore the effect of increasing surface density of polyMPC chains on corresponding anti-fouling properties. The novel free polymer was synthesized by a 3-step atom transfer radical polymerization (ATRP). First, poly(2-hydroxyethyl methacrylate) (polyHEMA) was polymerized by ATRP, where the hydroxyl (OH) groups of the polymer then underwent an esterification to create macroinitiating sites. From these sites, a second ATRP of poly(MPC) varying in length occurred, yielding the double-grafted polymer poly(2(2-bromoisobutyryloxy-ethyl methacrylate)-graft-poly(2-methacryloyloxyethyl phosphorylcholine (pBIBEM-g-pMPC). The polymer was designed for resistance to protein adsorption through a possible synergistic effect between the surface induced hydration layer by surrounding PC groups coupled with steric repulsion of the densely grafted chains. To test its potential as a surface modifier, the polymer was grafted from model silicone hydrogel CL through a 4-step surface initiated ATRP (SI-ATRP) in a similar manner to the free polymer. First, the ATRP initiator was immobilized from the HEMA OH groups of the unmodified CL, generating Intermedate-1. A polyHEMA brush was grafted from the initiating sites yielding pHEMA-50, followed by the generation of a second initiator layer (Intermediate- 2). A sequential ATRP of poly(MPC) then generated the target pMPC-50/pMPC-100 surfaces. For the free pBIBEM-g-pMPC polymer analysis, 1H-NMR and GPC determined polymers formed with a predictable MW and low polydispersity (PDI). For surface grafting, using a sacrificial initiator, 1H-NMR and GPC indicated that the pHEMA-50 and pMPC-50/pMPC-100 polymers were well-controlled, with a MW close to the theoretical and a low PDI. For surface chemical composition, ATR-FTIR showed the presence of the ATRP initiator (Intermediate-1 and 2) by the appearance of a C-Br peak and disappearance of the OH peak. XPS confirmed the chemical composition of the 4-step synthesis by a… Advisors/Committee Members: Sheardown, Heather, Biomedical Engineering.

Subjects/Keywords: Atom Transfer Radical Polymerization; Phosphorylcholine; Silicone Hydrogel Contact Lenses; Anti-fouling; Tear Film; 2-Methacryloyloxyethyl Phosphorylcholine

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Spadafora, A. (2017). Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/22798

Chicago Manual of Style (16^th Edition):

Spadafora, Alysha. “Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers.” 2017. Masters Thesis, McMaster University. Accessed February 27, 2021. http://hdl.handle.net/11375/22798.

MLA Handbook (7^th Edition):

Spadafora, Alysha. “Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers.” 2017. Web. 27 Feb 2021.

Vancouver:

Spadafora A. Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers. [Internet] [Masters thesis]. McMaster University; 2017. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/11375/22798.

Council of Science Editors:

Spadafora A. Surface Modification of Model Silicone Hydrogel Contact Lenses with Densely Grafted Phosphorylcholine Polymers. [Masters Thesis]. McMaster University; 2017. Available from: http://hdl.handle.net/11375/22798

Linnaeus University

26. Csobod, Sylvia. Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon.

Degree: Medicine and Optometry, 2013, Linnaeus University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26530

►

Syfte: Syftet med studien var att utvärdera om det fanns någon variation av tårfilmens osmolariet, morgon och kväll hos personer utan symptom av torra… (more)

▼

Syfte: Syftet med studien var att utvärdera om det fanns någon variation av tårfilmens osmolariet, morgon och kväll hos personer utan symptom av torra ögon. Metod: Tårfilmens osmolaritet mättes på totalt 30 patienter, två gånger på en dag; morgon och kväll. Mätningarna utfördes med TearLab^TM osmolarity system. Både höger och vänster öga mättes på varje patient. Samtliga deltagande ombads fylla i en symptomenkät vid namn TERTC-DEQ. Endast personer utan symptom på torra ögon tilläts delta i studien. Alltså personer med totalt 17 poäng på TERTC-DEQ. Resultat: Ingen statistisk signifikant skillnad kunde iakttas hos personernas osmolaritet mellan morgon och kväll (P > 0.05). Slutsats: I studien kunde ingen skillnad på osmolaritet i tårfilmen iakttas mellan morgon och kväll hos personer utan symptom på torra ögon. Därmed tros tårfunktionen hos dessa personer fungera korrekt. Tårfilmens osmolaritet upprätthåller rätt balans och förändras därför inte från morgon till kväll.

Aim: The aim of this study was to determine if there is an diurnal variation in tear osmolarity among healty non dry-eye subjects. Method: The osmolarity of the tearfilm was measured in a total of 30 subjects twice a day; morning and evening, using the TearLab^TM osmolarity system. Measurements were performed on both right and left eye in all the subjects. All subjects were asked to fill in a symptom questionnaire named TERTC-DEQ and only those with a total score of 17 points were allowed to participate in the study. Subjects below this score had therefore no symptoms of dry eye. Results: There was no statistical significant difference between the subjects tear osmolarity comparing the morning and evening values (P>0,05). Conclusion: This study did not show any difference in the subjects tear osmolarity, comparing morning and evening measurements. None of the individuals had any symptoms of dry eye. Therefore it is believed that in subjects with no symptoms of dry eye, the tear osmolarity remains stable between morning and evening.

Subjects/Keywords: osmolarity; tear film; tearlab; diurnal; variation; osmolaritet; tårfilm; tearlab; morgon; kväll; Medical and Health Sciences; Medicin och hälsovetenskap

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Csobod, S. (2013). Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon. (Thesis). Linnaeus University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26530

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Csobod, Sylvia. “Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon.” 2013. Thesis, Linnaeus University. Accessed February 27, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26530.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Csobod, Sylvia. “Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon.” 2013. Web. 27 Feb 2021.

Vancouver:

Csobod S. Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon. [Internet] [Thesis]. Linnaeus University; 2013. [cited 2021 Feb 27]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26530.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Csobod S. Förändringar av tårfilmens osmolaritet mellan morgon och kväll hos personer utan symptom på torra ögon. [Thesis]. Linnaeus University; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26530

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

27. Lu, Hui. Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging.

Degree: PhD, Electrical and Computer Engineering (Engineering), 2017, University of Miami

URL: https://scholarlyrepository.miami.edu/oa_dissertations/1792

► Dry eye debilitates the patients physically, limit their ability to perform daily tasks, cause clinical depression, and compromise quality of life. Accurate diagnosis of the… (more)

Subjects/Keywords: Tear Film; Reflectometry; Optical Coherence Tomography

…Anatomy of the Human Eye and Ocular Adnexa ....................................... Tear Film… …Currently Available Techniques for Tear Film Quantification .................. Aims of the Study… …Use of SD-OCT for Initial Study of Tear Film........................................... 18… …System ................................................................... Tear Film… …Reflectometry System for Tear Film Measurement ................... System Calibration and Measurement…

12 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lu, H. (2017). Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging. (Doctoral Dissertation). University of Miami. Retrieved from https://scholarlyrepository.miami.edu/oa_dissertations/1792

Chicago Manual of Style (16^th Edition):

Lu, Hui. “Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging.” 2017. Doctoral Dissertation, University of Miami. Accessed February 27, 2021. https://scholarlyrepository.miami.edu/oa_dissertations/1792.

MLA Handbook (7^th Edition):

Lu, Hui. “Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging.” 2017. Web. 27 Feb 2021.

Vancouver:

Lu H. Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging. [Internet] [Doctoral dissertation]. University of Miami; 2017. [cited 2021 Feb 27]. Available from: https://scholarlyrepository.miami.edu/oa_dissertations/1792.

Council of Science Editors:

Lu H. Reflectometry and Optical Coherence Tomography for Non-invasive High Resolution Tear Film Thickness Evaluation and Ophthalmic Imaging. [Doctoral Dissertation]. University of Miami; 2017. Available from: https://scholarlyrepository.miami.edu/oa_dissertations/1792

University of Edinburgh

28. Donora, Matthew. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.

Degree: PhD, 2020, University of Edinburgh

URL: http://hdl.handle.net/1842/37179

► Smart contact lenses (SCLs) are a new class of wearable medical device set to revolutionise the way we approach healthcare. SCLs have been designed for… (more)

▼ Smart contact lenses (SCLs) are a new class of wearable medical device set to revolutionise the way we approach healthcare. SCLs have been designed for functions such as active vision correction, drug delivery, display technology and chemical sensing. By integrating electrochemical sensors into SCLs, continuous, unobtrusive and non-invasive monitoring of chemical markers in the tear film may be carried out. However, despite significant advances in the past few years, an electrochemical smart contact lens (ESCL) suitable for clinical use has not yet been demonstrated. There are still design challenges which need to be addressed before this technology matures into real medical utility. The primary issues facing ESCLs today are the construction of a safe, comfortable device, and the fidelity of the measurements made in the tear film when compared to an equivalent measurement in the blood. Recent advances in SCL platforms may be used to inform a new ESCL design, and address the issues of discomfort or safe use. A clinically approved SCL for glaucoma treatment is already used in hospitals around the world, offering hope of a clear path to an approved ESCL. However, the question of measurement fidelity may represent a greater challenge. In this thesis, a next-generation ESCL is designed, built and characterised. The physical design follows previous work towards soft SCL platforms, and represents a significant improvement on the current ESCL state-of-the-art. To improve the quality of the measurements taken in this device, advanced electrochemical sensors are first investigated and developed on flexible substrates suitable for SCL integration. In the final design, a set of spatially distributed, individually addressable microelectrode arrays are integrated into a soft ESCL. A new electrochemical method is also developed to perform video-rate spatiotemporal electrochemical sensing, with very low power requirements and a minimum of driving logic complexity. In addition, a neural network method is developed to correct for the measurement distortion inherent to taking measurements in the tear film and attempting to make conclusions about the equivalent measurement in the blood. In combination, this new design and methodology greatly improves both safety and comfort of the ESCL, and makes progress towards an ESCL capable of taking measurements continuously and unobtrusively with real clinical utility.

Subjects/Keywords: smart contact lenses; electrochemical measurements; tear film; sensors; wearable medical devices; electrochemical smart contact lens; electrochemical sensing

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❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Donora, M. (2020). Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/37179

Chicago Manual of Style (16^th Edition):

Donora, Matthew. “Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.” 2020. Doctoral Dissertation, University of Edinburgh. Accessed February 27, 2021. http://hdl.handle.net/1842/37179.

MLA Handbook (7^th Edition):

Donora, Matthew. “Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.” 2020. Web. 27 Feb 2021.

Vancouver:

Donora M. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. [Internet] [Doctoral dissertation]. University of Edinburgh; 2020. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/1842/37179.

Council of Science Editors:

Donora M. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. [Doctoral Dissertation]. University of Edinburgh; 2020. Available from: http://hdl.handle.net/1842/37179

University of Edinburgh

29. Donora, Matthew. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.

Degree: PhD, 2020, University of Edinburgh

URL: https://doi.org/10.7488/era/480 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.810223

► Smart contact lenses (SCLs) are a new class of wearable medical device set to revolutionise the way we approach healthcare. SCLs have been designed for… (more)

▼ Smart contact lenses (SCLs) are a new class of wearable medical device set to revolutionise the way we approach healthcare. SCLs have been designed for functions such as active vision correction, drug delivery, display technology and chemical sensing. By integrating electrochemical sensors into SCLs, continuous, unobtrusive and non-invasive monitoring of chemical markers in the tear film may be carried out. However, despite significant advances in the past few years, an electrochemical smart contact lens (ESCL) suitable for clinical use has not yet been demonstrated. There are still design challenges which need to be addressed before this technology matures into real medical utility. The primary issues facing ESCLs today are the construction of a safe, comfortable device, and the fidelity of the measurements made in the tear film when compared to an equivalent measurement in the blood. Recent advances in SCL platforms may be used to inform a new ESCL design, and address the issues of discomfort or safe use. A clinically approved SCL for glaucoma treatment is already used in hospitals around the world, offering hope of a clear path to an approved ESCL. However, the question of measurement fidelity may represent a greater challenge. In this thesis, a next-generation ESCL is designed, built and characterised. The physical design follows previous work towards soft SCL platforms, and represents a significant improvement on the current ESCL state-of-the-art. To improve the quality of the measurements taken in this device, advanced electrochemical sensors are first investigated and developed on flexible substrates suitable for SCL integration. In the final design, a set of spatially distributed, individually addressable microelectrode arrays are integrated into a soft ESCL. A new electrochemical method is also developed to perform video-rate spatiotemporal electrochemical sensing, with very low power requirements and a minimum of driving logic complexity. In addition, a neural network method is developed to correct for the measurement distortion inherent to taking measurements in the tear film and attempting to make conclusions about the equivalent measurement in the blood. In combination, this new design and methodology greatly improves both safety and comfort of the ESCL, and makes progress towards an ESCL capable of taking measurements continuously and unobtrusively with real clinical utility.

Subjects/Keywords: smart contact lenses; electrochemical measurements; tear film; sensors; wearable medical devices; electrochemical smart contact lens; electrochemical sensing

Record Details Similar Records Cite « Share

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Donora, M. (2020). Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. (Doctoral Dissertation). University of Edinburgh. Retrieved from https://doi.org/10.7488/era/480 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.810223

Chicago Manual of Style (16^th Edition):

Donora, Matthew. “Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.” 2020. Doctoral Dissertation, University of Edinburgh. Accessed February 27, 2021. https://doi.org/10.7488/era/480 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.810223.

MLA Handbook (7^th Edition):

Donora, Matthew. “Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods.” 2020. Web. 27 Feb 2021.

Vancouver:

Donora M. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. [Internet] [Doctoral dissertation]. University of Edinburgh; 2020. [cited 2021 Feb 27]. Available from: https://doi.org/10.7488/era/480 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.810223.

Council of Science Editors:

Donora M. Spatially distributed microelectrode arrays in smart contact lenses : novel sensing designs, theory and methods. [Doctoral Dissertation]. University of Edinburgh; 2020. Available from: https://doi.org/10.7488/era/480 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.810223

University of Georgia

30. Wynne, Brittany Marie. Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels.

Degree: 2017, University of Georgia

URL: http://hdl.handle.net/10724/36619

► The endocrine system and the lacrimal functional unit are linked in ways that are not currently well understood. The included study investigated concentrations of the… (more)

Subjects/Keywords: CORTISOL; TEAR FILM; CORTICOSTEROID; CANINE HYPERADRENOCORTICISM; HYPOTHALAMIC-PITUITARY AXIS; EQUINE FUNGAL KERATITIS; EQUINE PITUITARY PARS INTERMEDIA DYSFUNCTION

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wynne, B. M. (2017). Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/36619

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wynne, Brittany Marie. “Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels.” 2017. Thesis, University of Georgia. Accessed February 27, 2021. http://hdl.handle.net/10724/36619.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wynne, Brittany Marie. “Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels.” 2017. Web. 27 Feb 2021.

Vancouver:

Wynne BM. Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels. [Internet] [Thesis]. University of Georgia; 2017. [cited 2021 Feb 27]. Available from: http://hdl.handle.net/10724/36619.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wynne BM. Cortisol and the tear film: the relationship between stress, adrenal disease and tear cortisol levels. [Thesis]. University of Georgia; 2017. Available from: http://hdl.handle.net/10724/36619

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations