subject:(Corneal biomechanics)

University of Rochester

1. Osapoetra, Laurentius Oscar; McAleavey, Stephen A. Quantitative corneal elastography using high-frequency ultrasound.

Degree: PhD, 2018, University of Rochester

URL: http://hdl.handle.net/1802/34276

► Measurement of corneal biomechanical properties can aid in predicting corneal responses to diseases and surgeries. Different biomechanical characteristics of the cornea have been studied primarily… (more)

Subjects/Keywords: Corneal biomechanics

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APA (6^th Edition):

Osapoetra, Laurentius Oscar; McAleavey, S. A. (2018). Quantitative corneal elastography using high-frequency ultrasound. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/34276

Chicago Manual of Style (16^th Edition):

Osapoetra, Laurentius Oscar; McAleavey, Stephen A. “Quantitative corneal elastography using high-frequency ultrasound.” 2018. Doctoral Dissertation, University of Rochester. Accessed March 09, 2021. http://hdl.handle.net/1802/34276.

MLA Handbook (7^th Edition):

Osapoetra, Laurentius Oscar; McAleavey, Stephen A. “Quantitative corneal elastography using high-frequency ultrasound.” 2018. Web. 09 Mar 2021.

Vancouver:

Osapoetra, Laurentius Oscar; McAleavey SA. Quantitative corneal elastography using high-frequency ultrasound. [Internet] [Doctoral dissertation]. University of Rochester; 2018. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1802/34276.

Council of Science Editors:

Osapoetra, Laurentius Oscar; McAleavey SA. Quantitative corneal elastography using high-frequency ultrasound. [Doctoral Dissertation]. University of Rochester; 2018. Available from: http://hdl.handle.net/1802/34276

University of Rochester

2. Ramirez Garcia, Manuel Alejandro. Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions.

Degree: PhD, 2020, University of Rochester

URL: http://hdl.handle.net/1802/35793

► The overall objective of my research is to apply novel engineering approaches to rigorously characterize the tissue- and cell-scale mechanical responses of the cornea in… (more)

▼ The overall objective of my research is to apply novel engineering approaches to rigorously characterize the tissue- and cell-scale mechanical responses of the cornea in order to elucidate the cause of and motivate improved clinical interventions for stromal- and endothelial-related corneal conditions. Specifically, I seek to inform novel strategies to reduce iatrogenic (surgically-induced) corneal endothelial cell (CEC) loss during corneal transplantation by developing novel experimental platforms to quantify the vulnerability of CECs to isolated, controlled, and measurable mechanical forces. I also aim to establish the relationship between the mechanical properties of the corneal stroma and its constituents in order to shed light on the etiology of stroma-related conditions. I will pursue my overall research objective through two specific aims: 1) characterize the effects of isolated mechanical loading regimes on corneal endothelial cell viability and 2) assess the effects of stromal proteoglycan removal on the biomechanical properties of the cornea. In Aim 1, two sub-aims will be explored to determine the impact of 1a) contact-based indentation forces, and 1b) bending moments on corneal endothelial cell viability. In Aim 2, two sub-aims will be explored to 2a) develop an experimental platform to determine the baseline location-dependent viscoelastic material properties of the human cornea and 2b) determine the effects of proteoglycan digestion on the anisotropic viscoelastic material properties of the porcine cornea. The results from Aim 1 indicate a critical threshold force exists where indentation-type forces do not cause CEC loss and curling is not a major contributor to iatrogenic trauma. These results are important because they complement clinical studies to advance understanding of iatrogenic trauma. In addition, these results can motivate new surgical tool development and technique modification to improve outcomes of corneal transplantation. The results from Aim 2 indicate that the depth-dependent out-of-plane Young’s Modulus profile of the peripheral and central cornea is uniform and that proteoglycans play an important and distinct role in the transverse shear modulus, out-of-plane Young’s modulus and in-plane Young’s modulus of the corneal stroma. Hence, stromal proteoglycans may play both a lubricating and cross-linking role with competing effects on biomechanical properties. These results are important because they highlight the importance of considering the cornea’s structural heterogeneity and anisotropy in measuring its material properties. Moreover, the individual measurements of each material property can be used as key input parameters in computational simulations of the cornea’s mechanical response. In addition, by understanding what role stromal proteoglycans play in the biomechanical properties of the cornea, we can better understand corneal conditions characterized by abnormal stromal proteoglycan content.

Subjects/Keywords: Corneal biomechanics; Corneal endothelial cell; Corneal surgery; Stromal proteoglycans; Surgical trauma; Transverse isotropic model

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APA (6^th Edition):

Ramirez Garcia, M. A. (2020). Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/35793

Chicago Manual of Style (16^th Edition):

Ramirez Garcia, Manuel Alejandro. “Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions.” 2020. Doctoral Dissertation, University of Rochester. Accessed March 09, 2021. http://hdl.handle.net/1802/35793.

MLA Handbook (7^th Edition):

Ramirez Garcia, Manuel Alejandro. “Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions.” 2020. Web. 09 Mar 2021.

Vancouver:

Ramirez Garcia MA. Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions. [Internet] [Doctoral dissertation]. University of Rochester; 2020. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1802/35793.

Council of Science Editors:

Ramirez Garcia MA. Engineering approaches to elucidate the causes of endothelial and stromal corneal conditions. [Doctoral Dissertation]. University of Rochester; 2020. Available from: http://hdl.handle.net/1802/35793

Freie Universität Berlin

3. Heinke, Melanie. Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis.

Degree: 2014, Freie Universität Berlin

URL: http://dx.doi.org/10.17169/refubium-7131

► Background: Rheumatoid arthritis (RA) is a systemic, primary inflammatory autoimmune connective tissue disease accompanied by a characteristic polyarticular inflammation. In most of the cases, more… (more)

▼ Background: Rheumatoid arthritis (RA) is a systemic, primary inflammatory autoimmune connective tissue disease accompanied by a characteristic polyarticular inflammation. In most of the cases, more than 3 joints are affected. The disease is characterized by synovial hyperplasia and progredient joint destruction. The typical joint affection of RA presents as infiltration of the synovial membrane with macrophages, B- and T-cells, which develops into a chronic synovialitis and attacks cartilage and bone structures. An ocular involvement is typical for a long disease duration of rheumatoid arthritis (RA) especially with a positive verification of rheumatoid factor. Typical ocular manifestations of RA are keratokonjunctivitis sicca, keratitis, episcleritis and scleritis. Because of a similar collagen structure in cartilage and cornea we performed the study to investigate whether patients suffering from RA exhibit changes in corneal biomechanics as a result of collagen reformation processes. Material and methods: 79 patients were included into the evaluation, with 38 patients suffering from RA (f:m = 31:7, average of age±standard deviation 57,47±5,04 years) and 41 persons (f:m = 31:10, 55,24±3,39 years) forming a control group. Inclusion criteria for the first group were RA of a duration of 10 years and more, because corneal remodeling needs 2-3 years. For selection of patients the classification critertia for RA according to the American College of Rheumatology (ACR) were applied. Besides the anamnesis following clinical examinations were performed: Visual acuity, slit lamp microscopy, Goldmann applanation tonometry, assessment of the central corneal thickness with Orbscan II as well as measurement of the biomechanical characteristics of the cornea with the Ocular Response Analyzer (ORA). Results: Concerning the corrected visual acuity, the spherical equivalent, the cup-disc-ratio and Goldmann applanation pressure there was no statistical difference between the two groups for the probability of error of p≤ 0,05. In addition no statistical significant difference of the corneal hysteresis (CH) and corneal resistance factor (CRF) were found between the two tested groups (mean± standard deviation, CH: RA 11,74± 1,35 mmHg; control group (C) 11,32± 1,46 mmHg; CRF: RA 11,41± 1,68 mmHg, C 10,80± 1,37 mmHg). Conclusion: Disregarding long duration of the disease (≥ 10 years), no corneal changes accompanying inflammatory processes and collagenosis could be found in the rheumatic group. However, the difference of the corneal thickness and intraocular pressure corrected values of CH and CRF (CHkorr - CRFkorr) shows statistically significant lower values in the patient group. The cornea in patients with RA seems to be fixed by a change in the content of extracellular matrix. Advisors/Committee Members: [email protected] (contact), w (gender), N.N. (firstReferee), N.N. (furtherReferee).

Subjects/Keywords: corneal biomechanical properties; corneal biomechanics; corneal hysteresis; corneal resistance factor; rheumatoid arthritis; 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit

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APA (6^th Edition):

Heinke, M. (2014). Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis. (Thesis). Freie Universität Berlin. Retrieved from http://dx.doi.org/10.17169/refubium-7131

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):

Heinke, Melanie. “Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis.” 2014. Thesis, Freie Universität Berlin. Accessed March 09, 2021. http://dx.doi.org/10.17169/refubium-7131.

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

MLA Handbook (7^th Edition):

Heinke, Melanie. “Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis.” 2014. Web. 09 Mar 2021.

Vancouver:

Heinke M. Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis. [Internet] [Thesis]. Freie Universität Berlin; 2014. [cited 2021 Mar 09]. Available from: http://dx.doi.org/10.17169/refubium-7131.

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

Council of Science Editors:

Heinke M. Clinical study to messure the corneal biomechanics in patients with rheumatoid arthritis. [Thesis]. Freie Universität Berlin; 2014. Available from: http://dx.doi.org/10.17169/refubium-7131

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

The Ohio State University

4. Tang, Junhua. Ultrasonic Characterization of Corneal and Scleral Biomechanics.

Degree: PhD, Biomedical Engineering, 2012, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354678642

► Cornea and sclera are the major load-bearing tissue of the eye and the biomechanics of the cornea and sclera have been shown to be critical… (more)

▼ Cornea and sclera are the major load-bearing tissue of the eye and the biomechanics of the cornea and sclera have been shown to be critical in the understanding, diagnosis and management of glaucoma. It is therefore important to non-invasively measure the mechanical properties of the cornea and sclera and examine their effects in glaucoma. The current study was designed to investigate the effect of corneal stiffness on intraocular pressure (IOP) and central corneal thickness (CCT) measurements and develop ultrasound-based techniques for non-invasive characterization of corneal and scleral biomechanics under physiological loadings and configurations. We first examined the effect of the natural variation in speed of sound in cornea on the measurement of corneal thickness, which is an important parameter affecting the IOP measurement and a risk factor of glaucoma. The effect of the variation in corneal stiffness on IOP measurement was examined experimentally, and a non-invasive ultrasound method for measuring acoustic impedance was used to estimate the corneal stiffness and potentially provide corrections for IOP measurement. An ultrasound strain imaging method based on speckle tracking was developed to characterize the mechanical response of the sclera under IOP elevations, and the performance of the ultrasound method was evaluated both experimentally and using simulations. The mechanical responses of the porcine and human sclera under IOP elevations were then examined by this ultrasound strain imaging method.The variance of speed of sound in cornea was shown to potentially produce significant error in corneal thickness measurement using the current clinical setting of speed of sound in ultrasound pachymetry. Corneal acoustic impedance was significantly correlated with the speed of sound in cornea and could potentially be used to improve corneal thickness measurement accuracy. The effect of corneal stiffness on IOP measurement was found to be significant, and the corneal acoustic impedance was significantly correlated with the IOP measurement error and the corneal stiffness measured through uniaxial tests. This correlation may provide necessary corrections for clinical IOP measurement. The ultrasound speckle tracking method developed for noninvasive measurement of through-thickness distributive strains of the sclera demonstrated excellent accuracy and high signal-to-noise ratio in both experimental and simulation results. The porcine and human sclera showed anisotropic, nonlinear, heterogeneous mechanical responses under IOP elevations.The current study demonstrated significant effects of corneal biomechanics on CCT and IOP measurement and the complexity of sclera biomechanics in response to IOP loadings. This research also established the feasibility of the proposed ultrasound methods as useful experimental and clinical tools to characterize corneal and scleral biomechanics non-invasively. Future studies should implement these techniques for measurement of corneal and scleral biomechanical properties in glaucoma… Advisors/Committee Members: Liu, Jun (Advisor).

Subjects/Keywords: Biomechanics; Biomedical Engineering; Ophthalmology; ultrasound; ultrasound elastography; corneal biomechanics; scleral biomechanics; glaucoma

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

APA (6^th Edition):

Tang, J. (2012). Ultrasonic Characterization of Corneal and Scleral Biomechanics. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1354678642

Chicago Manual of Style (16^th Edition):

Tang, Junhua. “Ultrasonic Characterization of Corneal and Scleral Biomechanics.” 2012. Doctoral Dissertation, The Ohio State University. Accessed March 09, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354678642.

MLA Handbook (7^th Edition):

Tang, Junhua. “Ultrasonic Characterization of Corneal and Scleral Biomechanics.” 2012. Web. 09 Mar 2021.

Vancouver:

Tang J. Ultrasonic Characterization of Corneal and Scleral Biomechanics. [Internet] [Doctoral dissertation]. The Ohio State University; 2012. [cited 2021 Mar 09]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354678642.

Council of Science Editors:

Tang J. Ultrasonic Characterization of Corneal and Scleral Biomechanics. [Doctoral Dissertation]. The Ohio State University; 2012. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354678642

Macquarie University

5. Viswanathan, Deepa. Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus.

Degree: 2015, Macquarie University

URL: http://hdl.handle.net/1959.14/1068058

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Thesis by publication.

1. Introduction and review of the literature – 2. Methods – 3. Longitudinal effect of topical antiglaucoma medications on central corneal thickness… (more)

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Thesis by publication.

1. Introduction and review of the literature – 2. Methods – 3. Longitudinal effect of topical antiglaucoma medications on central corneal thickness – 4. Relationship of change in central corneal thickness to visual field progression in eyes with glaucoma – 5. Relationship of biomechanical profile to structural characteristics in normal, forme fruste keratoconic, keratoconic and crosslinked corneas – 6. Comparative analysis of corneal measurements obtained from a scheimpflug camera and an integrated placido-optical coherence tomography device in normal and keratoconic eyes – 7. Sensitivity and specificity of newer biomechanical waveform parameters in detecting keratoconus – 8. Prospective longitudinal study of corneal collagen cross-linking in progressive keratoconus – 9. Outcome of corneal collagen crosslinking for progressive keratoconus in paediatric patients – 10A. Discussion and summary – 10B. Conclusions and future directions – References – Appendix.

This thesis extensively investigates the relationship of corneal structure and biomechanical profile to the diagnosis and treatment of two ocular disorders: glaucoma and keratoconus. The research papers arising out of these studies have been compiled to form this thesis by publication. The main hypotheses addressed by this PhD thesis include:

1. Baseline central corneal thickness could be a predictive factor of glaucoma progression 2. Ongoing change in corneal thickness may occur in glaucoma subjects and this might be related to glaucoma progression. 3. Altering the dynamic properties of the cornea by collagen crosslinking can affect the progression of disease in keratoconic subjects.

Despite having different mechanisms, both conditions are significant causes of preventable blindness. Glaucoma is more prevelant in the older population whereas keratoconus tends to affect younger subjects. Interestingly, thinner corneas and altered biomechanics are related to glaucoma risk and also characteristic of keratoconus. The aim of the glaucoma studies was to identify longitudinal variation in corneal thickness and its relationship to antiglaucoma medications and visual field progression. This could provide some insight on the clinical relevance of repeat corneal thickness measurements in glaucoma practice. Our findings indicate that corneal thickness reduces slightly over time in eyes on topical prostaglandin therapy and that thinner corneas may be associated with an increased risk of visual field progression.

The keratoconus studies aimed to explore the relationship between corneal structural and biomechanical characteristics, compare corneal imaging devices, analyse the sensitivity and specificity of biomechanical parameters in keratoconus detection and study the outcome of collagen crosslinking in adult and paediatric progressive keratoconic eyes. Knowledge from these studies would allow clinicians to identify and manage keratoconus more efficiently. Our results indicate significant correlations between corneal…

Advisors/Committee Members: Macquarie University. Australian School of Advanced Medicine.

Subjects/Keywords: Cornea – Diseases; Glaucoma – Diagnosis; Glaucoma – Treatment; Keratoconus – Diagnosis; Keratoconus – Treatment; glaucoma; keratoconus; corneal biomechanics

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

APA (6^th Edition):

Viswanathan, D. (2015). Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1068058

Chicago Manual of Style (16^th Edition):

Viswanathan, Deepa. “Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus.” 2015. Doctoral Dissertation, Macquarie University. Accessed March 09, 2021. http://hdl.handle.net/1959.14/1068058.

MLA Handbook (7^th Edition):

Viswanathan, Deepa. “Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus.” 2015. Web. 09 Mar 2021.

Vancouver:

Viswanathan D. Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus. [Internet] [Doctoral dissertation]. Macquarie University; 2015. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/1959.14/1068058.

Council of Science Editors:

Viswanathan D. Corneal structure and biomechanics: relationship to diagnosis and treatment of glaucoma and keratoconus. [Doctoral Dissertation]. Macquarie University; 2015. Available from: http://hdl.handle.net/1959.14/1068058

6. Oehring, Daniela. Ocular biomechanics of the anterior segment.

Degree: PhD, 2018, University of Plymouth

URL: http://hdl.handle.net/10026.1/10647

► The thesis investigates methods of examining corneal biomechanics using non-contact tonometry and introduces novel techniques to investigate corneal material properties in vivo. A comprehensive systems… (more)

▼ The thesis investigates methods of examining corneal biomechanics using non-contact tonometry and introduces novel techniques to investigate corneal material properties in vivo. A comprehensive systems analysis of the CorvisST (CST) and Ocular Response Analyser (ORA) was performed. Pressure sensors were used to characterisation the airflow produced by the CST and the ORA. Distinct differences were observed between the central airflow pressures between the two devices: the CST pressure was higher and of shorter duration. Scheimpflug high-speed imaging via the CST allowed components of the corneal deformation to be investigated and the development of a 3D deformation matrix (time, depth and spatial resolution) through tracing of the anterior and posterior corneal surface. Measures of whole eye movement (WEM) with CST were found to be robust. WEM demonstrated an asymmetric profile and a correction method was developed to address the corneal deformation matrix for this asymmetry. Novel methods for characterisation of intrinsic material characteristics of the cornea were developed using numerical and graphical analytical procedures. Application of these parameters was tested on enucleated porcine eyes across a wide range of manometry internal ocular pressure (MIOP). The dynamic E-Modulus was found to be most affected by MIOP change. To investigate the in vivo distribution and heterogeneity of the corneal biomechanics, a novel set-up allowed the mapping of corneal biomechanics across the cornea using the CST (central, paracentral, peripheral) and ORA (central, peripheral). Biometric and demographic grouping of subjects allowed detection of discriminating factors between individuals. The results suggest that the in vivo cornea of healthy human adults can be characterised as a viscoelastic, damped system for longitudinal strain and a highly oscillating system for lateral strain. The cornea is approximately homogenous for measures of rigidity and dynamic E-Modulus but other corneal material characteristics (longitudinal and lateral strain, hysteresis, damping and compressibility) demonstrated regional differences. The experimental design employed allowed for strict control of biometric and biomechanical intersubject variables, based on gold-standard techniques as well as newly-developed methods, thereby creating a normative database for future use.

Subjects/Keywords: 617.7; Cornea; Biomechanical properties; Anterior ocular segment; Corneal hysteresis; CorvisST; Ocular Response Analyzer; Corneal Young's modulus; Corneal deflection behavior; Regional variation of the corneal biomechanics; Airpuff tonometry; Non contact tonometry; Airstream NCT; Globe retraction; Whole eye movement

10 more images…

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APA (6^th Edition):

Oehring, D. (2018). Ocular biomechanics of the anterior segment. (Doctoral Dissertation). University of Plymouth. Retrieved from http://hdl.handle.net/10026.1/10647

Chicago Manual of Style (16^th Edition):

Oehring, Daniela. “Ocular biomechanics of the anterior segment.” 2018. Doctoral Dissertation, University of Plymouth. Accessed March 09, 2021. http://hdl.handle.net/10026.1/10647.

MLA Handbook (7^th Edition):

Oehring, Daniela. “Ocular biomechanics of the anterior segment.” 2018. Web. 09 Mar 2021.

Vancouver:

Oehring D. Ocular biomechanics of the anterior segment. [Internet] [Doctoral dissertation]. University of Plymouth; 2018. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/10026.1/10647.

Council of Science Editors:

Oehring D. Ocular biomechanics of the anterior segment. [Doctoral Dissertation]. University of Plymouth; 2018. Available from: http://hdl.handle.net/10026.1/10647

Freie Universität Berlin

7. Riedel, Eileen. Biomechanical properties of the cornea in patients with systemic lupus erythematosus.

Degree: 2016, Freie Universität Berlin

URL: http://dx.doi.org/10.17169/refubium-5834

► Subject and Methods: Systemic Lupus Erythematosus is an autoimmune disease able to effect all organ systems – including the eye. In this study 15 ANA-… (more)

Subjects/Keywords: Systemic Lupus Erythematosus; Ocular Response Analyzer; Pentacam; corneal properties; corneal biomechanics; ocular manifestation; 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit

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APA (6^th Edition):

Riedel, E. (2016). Biomechanical properties of the cornea in patients with systemic lupus erythematosus. (Thesis). Freie Universität Berlin. Retrieved from http://dx.doi.org/10.17169/refubium-5834

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):

Riedel, Eileen. “Biomechanical properties of the cornea in patients with systemic lupus erythematosus.” 2016. Thesis, Freie Universität Berlin. Accessed March 09, 2021. http://dx.doi.org/10.17169/refubium-5834.

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

MLA Handbook (7^th Edition):

Riedel, Eileen. “Biomechanical properties of the cornea in patients with systemic lupus erythematosus.” 2016. Web. 09 Mar 2021.

Vancouver:

Riedel E. Biomechanical properties of the cornea in patients with systemic lupus erythematosus. [Internet] [Thesis]. Freie Universität Berlin; 2016. [cited 2021 Mar 09]. Available from: http://dx.doi.org/10.17169/refubium-5834.

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

Council of Science Editors:

Riedel E. Biomechanical properties of the cornea in patients with systemic lupus erythematosus. [Thesis]. Freie Universität Berlin; 2016. Available from: http://dx.doi.org/10.17169/refubium-5834

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

Loughborough University

8. Wilson, Abby. An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics.

Degree: PhD, 2017, Loughborough University

URL: http://hdl.handle.net/2134/28380

► There has been widespread interest in corneal biomechanics over recent years, driven largely by the advancements in, and the popularity of refractive surgery techniques and… (more)

▼ There has been widespread interest in corneal biomechanics over recent years, driven largely by the advancements in, and the popularity of refractive surgery techniques and subsequent concerns over their safety. Lately there has been interest into whether crosslinking, which is currently used for the treatment of keratoconus, could be developed as a minimally invasive technique to change the refractive power of the cornea by selectively changing the corneal biomechanics in specific regions to induce a shape change. Successful application of this technique requires a detailed understanding of corneal biomechanics and so far, little is known about the biomechanics of this complex tissue. The current lack of understanding can be mostly attributed to the absence of a suitable measurement technique capable of examining the dynamic behaviour of the cornea under physiological loading conditions. This thesis describes the development of a novel full-field, ex vivo, measurement method incorporating speckle interferometric techniques, to examine the biomechanics of the cornea before and after crosslinking in response to hydrostatic pressure fluctuations representative of those that occur in vivo during the cardiac cycle. The eventual measurement system used for the experiments detailed in this thesis incorporated; an Electronic Speckle Pattern Interferometer (ESPI), a Lateral Shearing Interferometer (LSI) and a fringe projection shape measurement system. The combination of these systems enabled the 3-dimensional components of surface displacement and the 1st derivative of surface displacement to be determined in response to small pressure fluctuations up to 1 mmHg in magnitude. The use of both ESPI and LSI together also enabled the applicability of LSI for measurement of non-flat surfaces to be assessed, and limitations and error sources to be identified throughout this work. To enable the measurement of corneal biomechanics, part of this thesis was concerned with the design of a bespoke loading rig. A chamber was designed that could accommodate tissue of both porcine and human origin. This chamber was linked to a hydraulic loading rig, whereby the cornea could be held at a baseline pressure representative of normal intraocular pressure and small pressure variations could be introduced by the automated vertical movement of the reservoir supplying the chamber. Experiments were conducted on a range of non-biological samples with both flat and curved surface topography, and both uniform and non-uniform mechanical properties, to determine if the measurement configuration was giving the expected measurement data and the loading rig was stable and repeatable. Following experiments on non-biological samples, a range of experiments were conducted on porcine corneas to develop a suitable testing methodology and address some of the challenges associated with corneal measurement, including transparency and hydration instability. During these investigations, a suitable surface coating was identified to generate an adequate return signal…

Subjects/Keywords: 617.7; Cornea; Laser Speckle Interferometry; ESPI; Lateral Shearing Interferometry; Biomechanics; Refractive surgery; Corneal crosslinking; Keratoconus; Topographic crosslinking; Customised crosslinking

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

APA (6^th Edition):

Wilson, A. (2017). An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics. (Doctoral Dissertation). Loughborough University. Retrieved from http://hdl.handle.net/2134/28380

Chicago Manual of Style (16^th Edition):

Wilson, Abby. “An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics.” 2017. Doctoral Dissertation, Loughborough University. Accessed March 09, 2021. http://hdl.handle.net/2134/28380.

MLA Handbook (7^th Edition):

Wilson, Abby. “An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics.” 2017. Web. 09 Mar 2021.

Vancouver:

Wilson A. An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics. [Internet] [Doctoral dissertation]. Loughborough University; 2017. [cited 2021 Mar 09]. Available from: http://hdl.handle.net/2134/28380.

Council of Science Editors:

Wilson A. An investigation into the use of Laser Speckle Interferometry for the analysis of corneal deformation with relation to biomechanics. [Doctoral Dissertation]. Loughborough University; 2017. Available from: http://hdl.handle.net/2134/28380

9. Schweitzer, Cédric. Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study.

Degree: Docteur es, Santé publique. Option : Epidémiologie, 2016, Bordeaux

URL: http://www.theses.fr/2016BORD0186

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Le glaucome est une maladie neurodégénérative qui se définit par une perte progressive en fibres nerveuses rétiniennes et un rétrécissement du champ visuel. Il s’agit… (more)

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Le glaucome est une maladie neurodégénérative qui se définit par une perte progressive en fibres nerveuses rétiniennes et un rétrécissement du champ visuel. Il s’agit de la première cause de cécité irréversible dans le monde et le principal facteur de risque est la pression intraoculaire (PIO). L’étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies OculaiRes) est une étude épidémiologique qui a pour but de déterminer l’incidence des différentes pathologies oculaires liées à l’âge avec les facteurs nutritionnels, démographiques ou environnementaux dans une population représentative de la région de Bordeaux. En 2009-2010, 624 sujets âgés de plus de 74 ans ont bénéficié d’un examen ophtalmologique complet incluant un examen du nerf optique en rétinophotographie et en tomographie à cohérence optique spectral-domain (SD-OCT), d’une mesure la PIO au tonomètre à air et d’une évaluation des propriétés biomécaniques de la cornée. Une mesure de l’accumulation cutanée de produits de glycation avancée a été réalisée par autofluorescence. Le diagnostic de glaucome a été réalisé en utilisant les critères de la classification ISGEO (International Society for Epidemiologic and Geographical Ophthalmology). Les paramètres biomécaniques de la cornée étaient modifiés avec l’âge et chez les sujets ayant une histoire résidentielle à des latitudes plus exposées aux ultraviolets ambiants. L’épaisseur de cornée était plus élevée chez les sujets anciennement fumeurs. L’autofluorescence cutanée ≥ 2.7 UA (Unité Arbitraire) était indépendamment associée au glaucome. Les paramètres d’épaisseur en fibres nerveuses rétiniennes du SD-OCT présentaient de bonnes performances diagnostiques pour discriminer les sujets glaucomateux des témoins et la base normative présentait de bonnes performances discriminatives lorsqu’au moins un des paramètres était considéré comme anormal. Notre étude apporte des résultats originaux en termes de facteurs de risque de glaucome ou de déterminants des facteurs de risque de glaucome. De plus les performances diagnostiques du SD-OCT pourraient fournir des informations utiles pour optimiser les stratégies de dépistage du glaucome dans une population générale âgée.

Glaucoma is a neurodegenerative disease defined by a progressive loss of optic nerve axons and retinal ganglion cells resulting in a characteristic enlargement of the optic nerve head cup and associated visual field defects. It remains the first cause of irreversible blindness worldwide and intraocular pressure (IOP) is the main risk factor. The ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies OculaiRes) study is a population-based study. It aims to assess the associations of age-related eye diseases with nutritional, demographic and environmental factors in a representative population of the Bordeaux area. In 2009-2010, 624 subjects, aged 74 years or more, underwent a complete eye examination, including an optic nerve head evaluation using retinophotography and a spectral-domain optical coherence tomography (SD-OCT), an IOP…

Advisors/Committee Members: Delcourt, Cécile (thesis director).

Subjects/Keywords: Epidémiologie; Glaucome; Vieillissement oculaire; Dépistage glaucome; Biomécanique cornéenne; Produits de glycation avancée; Epidemiology; Glaucoma; Age-related eye disease; Glaucoma screening; Corneal biomechanics; Advanced glycation end-products

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

APA (6^th Edition):

Schweitzer, C. (2016). Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2016BORD0186

Chicago Manual of Style (16^th Edition):

Schweitzer, Cédric. “Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study.” 2016. Doctoral Dissertation, Bordeaux. Accessed March 09, 2021. http://www.theses.fr/2016BORD0186.

MLA Handbook (7^th Edition):

Schweitzer, Cédric. “Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study.” 2016. Web. 09 Mar 2021.

Vancouver:

Schweitzer C. Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study. [Internet] [Doctoral dissertation]. Bordeaux; 2016. [cited 2021 Mar 09]. Available from: http://www.theses.fr/2016BORD0186.

Council of Science Editors:

Schweitzer C. Analyse épidémiologique du glaucome dans une population âgée : l'étude ALIENOR (Antioxydants, Lipides Essentiels, Nutrition et maladies Occulaires) : Epidemiology ou glaucoma in an elderly population : the Alienor Study. [Doctoral Dissertation]. Bordeaux; 2016. Available from: http://www.theses.fr/2016BORD0186

University of Houston

10. Vantipalli, Srilatha. Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography.

Degree: PhD, Physiological Optics and Vision Science, University of Houston

URL: http://hdl.handle.net/10657/3625

► Purpose: Optical coherence elastography (OCE) quantifies the tissue’s biomechanical properties through mechanical loading and imaging the tissue response using optical coherence tomography (OCT). Current techniques… (more)

▼ Purpose: Optical coherence elastography (OCE) quantifies the tissue’s biomechanical properties through mechanical loading and imaging the tissue response using optical coherence tomography (OCT). Current techniques evaluating corneal stiffness do not account for the influence of key physiological factors on the measured corneal biomechanical properties and either require contact, or create global deformations masking the localized variations: the hallmark of corneal ectasias, e.g., keratoconus. To implement OCE in the cornea, we developed a micro air-pulse stimulator that provides non-contact, dynamic, spatially localized, tissue stimulation. This dissertation determines a) the acute effects of tissue hydration and UV riboflavin cross-linking (CXL) treatment on the corneal ultrastructure, and evaluates the corneal biomechanical properties determined using OCE due to the effect of b) hydration and CXL treatment, c) deep stromal cross-linking treatments and d) in vivo application. Methods: a) Ex vivo de-epithelialized rabbit corneas (n=11) were cross-linked instilling 0.1% riboflavin solution for 30min across the whole cornea and UV irradiation (365nm, 3mW/cm2) to only the temporal half-region for 30min while instilling riboflavin and processed for light and transmission electron microscopy. Corneal thickness and collagen fibril separation computed as the average radial inter-fibrillar distance from the sampled fibril cross-sectional electron micrographs were recorded. b) OCE imaging was performed using phase-sensitive OCT imaging to quantify the tissue deformation dynamics resulting from a spatially discrete, low-force air-pulse (150μm spot size; 0.8ms duration; <10Pa (<0.08mmHg)). The time-dependent surface deformation is characterized by a viscoelastic tissue recovery response, quantified by an exponential decay constant—relaxation rate (RR). Higher RR is consistent with increased stiffness. Hydration influence was determined (n=10) instilling 0.9% saline every 5min for 60min and 20% dextran for another 60min. Measurements were made every 20min to determine central corneal thickness (CCT) and RR. Hydration and CXL effects were determined by obtaining OCE measurements on cross-linked corneas using isotonic (n=6) and hypertonic (n=7) riboflavin. c) OCE measurements were performed (n=10) at: the de-epithelialized stromal surface, 2/3rd corneal depth post-trephination, and after deep stromal cross-linking treatment. Rose bengal green light cross-linking (RGX) using 0.1% rose bengal solution for 20min (n=5) and 10min green light irradiation (565nm, 0.25W/cm2) and CXL treatment (n=5) was performed in the deep stroma. d) In vivo OCE was performed on anesthetized Dutch belted rabbits (n=20) recording within-session (IOP: 10, 20, 30, 40mmHg) and between sessions RR measurements before and after animal re-positioning (10mmHg). Results: a) Corneal thickness decreased significantly (−56%) after CXL treatment. Anterior collagen fibril spacing decreased significantly in the paired CXL treated region (−23%) showing that acute… Advisors/Committee Members: Frishman, Laura J. (advisor), Twa, Michael D. (committee member), Burns, Alan R. (committee member), Marsack, Jason D. (committee member), Larin, Kirill V. (committee member), Miller, William L. (committee member).

Subjects/Keywords: Cornea; Optical coherence elastography; Vision sciences; Corneal biomechanics; Collagen cross-linking

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APA (6^th Edition):

Vantipalli, S. (n.d.). Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/3625

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16^th Edition):

Vantipalli, Srilatha. “Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography.” Doctoral Dissertation, University of Houston. Accessed March 09, 2021. http://hdl.handle.net/10657/3625.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7^th Edition):

Vantipalli, Srilatha. “Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography.” Web. 09 Mar 2021.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Vantipalli S. Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography. [Internet] [Doctoral dissertation]. University of Houston; [cited 2021 Mar 09]. Available from: http://hdl.handle.net/10657/3625.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Vantipalli S. Characterizing Corneal Biomechanical Properties Using Dynamic Optical Coherence Elastography. [Doctoral Dissertation]. University of Houston; Available from: http://hdl.handle.net/10657/3625

Note: this citation may be lacking information needed for this citation format:
No year of publication.

11. Dias, Janice Maxine. Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques.

Degree: PhD, Biomedical Engineering (Engineering), 2014, University of Miami

URL: https://scholarlyrepository.miami.edu/oa_dissertations/1332

► Corneal biomechanics has become an increasingly important field within ophthalmology. Striving to establish a relationship between corneal physiological structure and function, corneal biomechanics is… (more)

Subjects/Keywords: Corneal biomechanics; Atomic Force Microscopy; Tissue Biomechanics; Characterization; Ophthalmology; Cornea Crosslinking

…2.2 Corneal Biomechanics… …Corneal biomechanics is an important parameter for designing, developing and improving… …2009). 2.2 Corneal Biomechanics 2.2.1 Significance Although extensive research… …biomechanics has yet to arrive to the same level of standardization and mastery. Corneal biomechanics… …understanding of corneal biomechanics is required if they are to serve as an indication of normal and…

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

APA (6^th Edition):

Dias, J. M. (2014). Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques. (Doctoral Dissertation). University of Miami. Retrieved from https://scholarlyrepository.miami.edu/oa_dissertations/1332

Chicago Manual of Style (16^th Edition):

Dias, Janice Maxine. “Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques.” 2014. Doctoral Dissertation, University of Miami. Accessed March 09, 2021. https://scholarlyrepository.miami.edu/oa_dissertations/1332.

MLA Handbook (7^th Edition):

Dias, Janice Maxine. “Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques.” 2014. Web. 09 Mar 2021.

Vancouver:

Dias JM. Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques. [Internet] [Doctoral dissertation]. University of Miami; 2014. [cited 2021 Mar 09]. Available from: https://scholarlyrepository.miami.edu/oa_dissertations/1332.

Council of Science Editors:

Dias JM. Characterization of Corneal Biomechanics using Customized Atomic Force Microscopy Techniques. [Doctoral Dissertation]. University of Miami; 2014. Available from: https://scholarlyrepository.miami.edu/oa_dissertations/1332

12. Ford, Matthew R. Development and Application of Optical Coherence Elastography for Corneal Biomechanics.

Degree: PhD, Biomedical Engineering, 2015, Case Western Reserve University School of Graduate Studies

URL: http://rave.ohiolink.edu/etdc/view?acc_num=case1436545044

► The biomechanical properties of the cornea are an important determinant of both the shape and function of the human visual system. Measuring the biomechanical properties… (more)

Subjects/Keywords: Biomedical Engineering; Biomedical Research; Biomechanics; Medical Imaging; Ophthalmology; Optical Coherence Tomography; Elastography; Cornea; Biomechanics; Corneal Biomechanics; Shear Wave

…Glycosaminoglycans ix Development and Application of Optical Coherence Elastography for Corneal… …Biomechanics By MATTHEW R FORD Abstract The biomechanical properties of the cornea are an important… …application of OCE to corneal measurement was made possible by the use of speckle tracking in the… …corneal stroma. Application of OCE to human donor corneas was used to measure the biomechanical… …crosslinking (CXL). The corneal mechanical properties were shown to increase in stiffness…

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APA (6^th Edition):

Ford, M. R. (2015). Development and Application of Optical Coherence Elastography for Corneal Biomechanics. (Doctoral Dissertation). Case Western Reserve University School of Graduate Studies. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=case1436545044

Chicago Manual of Style (16^th Edition):

Ford, Matthew R. “Development and Application of Optical Coherence Elastography for Corneal Biomechanics.” 2015. Doctoral Dissertation, Case Western Reserve University School of Graduate Studies. Accessed March 09, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1436545044.

MLA Handbook (7^th Edition):

Ford, Matthew R. “Development and Application of Optical Coherence Elastography for Corneal Biomechanics.” 2015. Web. 09 Mar 2021.

Vancouver:

Ford MR. Development and Application of Optical Coherence Elastography for Corneal Biomechanics. [Internet] [Doctoral dissertation]. Case Western Reserve University School of Graduate Studies; 2015. [cited 2021 Mar 09]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1436545044.

Council of Science Editors:

Ford MR. Development and Application of Optical Coherence Elastography for Corneal Biomechanics. [Doctoral Dissertation]. Case Western Reserve University School of Graduate Studies; 2015. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1436545044

13. Medeiros, Fabricio Witzel de. Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.

Degree: PhD, Oftalmologia, 2011, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;

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Objetivo: Investigar as alterações biomecânicas da córnea de suínos induzidas pela confecção de lamelas pediculadas de diferentes espessuras pelo laser de femtossegundo. Métodos: Para a… (more)

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Objetivo: Investigar as alterações biomecânicas da córnea de suínos induzidas pela confecção de lamelas pediculadas de diferentes espessuras pelo laser de femtossegundo. Métodos: Para a formação dos dois grupos, 12 olhos de porcos foram usados: lamelas pediculadas de 100 e de 300 micrômetros confeccionadas pelo laser de femtossegundo. Cada olho foi submetido aos seguintes exames, antes da criação das lamelas: topografia por rasterstereography, Ocular Response Analyzer (ORA), tomografia do segmento anterior por coerência óptica para a avaliação paquimétrica corneal e das lamelas criadas e sistema de velocidade de onda (SVO), que mede a velocidade de propagação de ondas acústicas entre dois transdutores posicionados na superfície corneal antes e imediatamente, após a feitura da lamela. O primerio passo foi desenhado para o estudo das diferenças em relação à histerese corneal, fator de resistência corneal, mudanças na curvatura e velocidade de propagação de onda acústica entre córneas com lamelas finas e espessas. Posteriormente, as lamelas foram amputadas, e as medidas do sistema de velocidade de onda foram repetidas. Resultados: A média de espessura das lamelas ± desviopadrão (DP) foi de 108,5±6,9 (8,5% da espessura total) e 307,8±11,5 m (22,9% da espessura total), para os grupos de lamelas finas e espessas, respectivamente (p< 0,001). Histerese corneal e o fator de resistência corneal não apresentaram diferença estatística, após a criação de lamelas finas (p = 0,81 e p = 0,62, respectivamente). Histerese corneal foi significantemente mais baixa, depois da confecção de lamelas mais espessas (8,0±1,0 para 5,1±1,5 mmHg para medidas pré e pós-operatórias, respectivamente, p = 0,003, diminuição de 36,25%) e fator de resistência corneal também mostrou significante diminuição nesse grupo, após o procedimento cirúrgico; valores médios pré e pós-operatórios de 8,2±1,6 e 4,1±2,5 mmHg respectivamente (p= 0,007), diminuição de 50%. A ceratometria média simulada apresentou maiores valores, após a confecção das lamelas mais espessas em relação ao pré-operatório (ceratometria pré e pós-operatória de 39,5±1 D e 45,9±1,2 D, respectivamente, p= 0,003). Para o grupo de lamelas finas, não houve diferença estatisticamente significante (ceratometria pré e pós-operatória de 40,6±0,6 D e 41,4±1,0 D, respectivamente, p=0,55). Em relação ao Sistema de Velocidade de Onda, após a criação das lamelas e sua amputação, houve diminuição da velocidade de propagação acústica, embora na maior parte das posições não fosse estatisticamente significante. Conclusão: Nas condições experimentais estabelecidas por este estudo, a criação de lamelas de maior espessura pareceu exercer efeito mais relevante sobre a biomecânica da córnea de suínos

Purpose: To study the impact of programmed flaps at two different thicknesses on the biomechanical properties of the swine corneas. Methods: Twelve pig eyes were enrolled in this study and were formed two groups: 100m and 300 m flaps performed with the femtosecond laser. Each eye had the following procedure before…

Advisors/Committee Members: Alves, Milton Ruiz.

Subjects/Keywords: Biomecânica; Biomechanics; Ceratomileuse assistida por excimer laser in situ; Cirurgia refrativa; Cornea; Córnea; Corneal topography; Ectasia; Ectasia; Flaps; Histerese; Histeresis; Lamelas pediculadas; Laser-assisted in situ keratomileusis; Pachymetry; Paquimetria; Refractive surgery; Topografia da córnea

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

APA (6^th Edition):

Medeiros, F. W. d. (2011). Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;

Chicago Manual of Style (16^th Edition):

Medeiros, Fabricio Witzel de. “Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.” 2011. Doctoral Dissertation, University of São Paulo. Accessed March 09, 2021. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;.

MLA Handbook (7^th Edition):

Medeiros, Fabricio Witzel de. “Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo.” 2011. Web. 09 Mar 2021.

Vancouver:

Medeiros FWd. Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. [Internet] [Doctoral dissertation]. University of São Paulo; 2011. [cited 2021 Mar 09]. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;.

Council of Science Editors:

Medeiros FWd. Alterações biomecânicas da córnea de suínos induzidas pela confecções de lamelas pediculadas de diferentes espessuras por laser de femtossegundo. [Doctoral Dissertation]. University of São Paulo; 2011. Available from: http://www.teses.usp.br/teses/disponiveis/5/5149/tde-22082011-123320/ ;

14. Touboul, David. Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment.

Degree: Docteur es, Biologie Cellulaire et Physiopathologie, 2014, Bordeaux

URL: http://www.theses.fr/2014BORD0051

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Le cross-linking du collagène cornéen (CXL) est une cornéoplastie mini-invasive reposant surun concept biomécanique difficile à objectiver physiquement et dont les preuves del’efficacité thérapeutique sont… (more)

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Le cross-linking du collagène cornéen (CXL) est une cornéoplastie mini-invasive reposant surun concept biomécanique difficile à objectiver physiquement et dont les preuves del’efficacité thérapeutique sont d’interprétation complexe. Les principes, les nuances et lesrésultats du CXL sont colligés dans cette thèse afin de valider l’intérêt du modèleexpérimental choisi pour tester la pertinence de notre travail de recherche sur l’élastographiecornéenne par ondes de cisaillement.Notre cheminement expérimental a abouti au choix du modèle de CXL trans-épithélial (TCXL)assisté par iontophorèse (I-CXL), réalisé in vivo, sur oeil de lapin. Les mesuresélastographiques obtenues après euthanasie ont ainsi pu démontrer une modificationsignificative du profil d’élasticité de la cornée après CXL, testé successivement de manièredynamique et statique.Nos résultats confirment donc l’efficacité biomécanique instantanée du I-CXL et donnent uneidée plus précise de la valeur de la photo-polymérisation du tissu cornéen isolée desphénomènes liés à la cicatrisation. Les enjeux technologiques de l’élastographe cornéen paranalyse des ondes de cisaillement ont pu être définis afin de développer une stratégie de miseen oeuvre d’un système pertinent pour la pratique clinique.

Corneal collagen cross-linking (CXL) is a kind of minimaly invasive corneoplasty mainlybased on a biomechanical concept, which is very difficult to measure physically, and whichthe therapeutic efficacy understanding is complex.Principles, different protocols and resultsare summarized in this thesis in order to illustrate the usefulness of the experimental modelchosen in our experimentations about elastographic corneal shear wave imaging.The pathway of our experimental work have led to the choice of trans-epithelial CXL (TCXL)assisted by iontophoresis (I-CXL), performed in vivo, on rabbits eyes. Elastographicmeasurements we obtained after animals euthanasia have shown a significant change of thecorneal elasticity profile after CXL, successively tested in a dynamic and in a static fashion.Our results do confirm the biomechanical efficacy of the I-CXL procedure and give a moreprecise idea of the sole photo-polymerization effect by avoiding any confounding healingconcern. Technological issues for corneal elastography with shear wave imaging have beenraised in this thesis to develop a realistic strategy for the launch of a clinically useful device.

Advisors/Committee Members: Grenier, Nicolas (thesis director).

Subjects/Keywords: Cornée; Biomécanique; Elastographie; Ondes de cisaillement; Imagerie supersonique; Elasticité; Kératocône; Photo-polymérisation du collagène cornéen (CXL); Riboflavine; Iontophorèse; Cornea; Biomechanics; Elastography; Shear wave; Supersonic Imaging; Elasticity; Keratoconus; Corneal collagen cross-linking (CXL); Riboflavin; Iontophoresis

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

APA (6^th Edition):

Touboul, D. (2014). Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2014BORD0051

Chicago Manual of Style (16^th Edition):

Touboul, David. “Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment.” 2014. Doctoral Dissertation, Bordeaux. Accessed March 09, 2021. http://www.theses.fr/2014BORD0051.

MLA Handbook (7^th Edition):

Touboul, David. “Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment.” 2014. Web. 09 Mar 2021.

Vancouver:

Touboul D. Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment. [Internet] [Doctoral dissertation]. Bordeaux; 2014. [cited 2021 Mar 09]. Available from: http://www.theses.fr/2014BORD0051.

Council of Science Editors:

Touboul D. Apport de l’élastographie par imagerie des ondes de cisaillement pour l’évaluation de la photo-polymerisation du collagène cornéen : Contribution of shear wave imaging elastography for corneal collagen photo-polymerization assessment. [Doctoral Dissertation]. Bordeaux; 2014. Available from: http://www.theses.fr/2014BORD0051

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Open Access Theses and Dissertations