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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

"Desempenho visual na correção de miopia com óculos e lentes de contato gelatinosas" / Visual performance in myopic correction with spectacles and soft contact lenses

Breno Barth Amaral de Andrade 24 September 2004 (has links)
Objetivos: Avaliar o desempenho visual(DV), por meio da AV logMAR de alto contraste, sensibilidade ao contaste(SC) e análise de frentes de onda(AFO), em míopes, com óculos e três LCG. Métodos: Estudo clínico e prospectivo, em 40 indivíduos míopes(-1,00D e -4,50D). Exames: AV logMAR de alto contraste, avaliação de SC e AFO. Resultados: A AFO detectou diferença na aberração de terceira ordem sem e com as LCG.. Em relação ao nível trifoil houve diferença entre com e sem LCG. Conclusões: Na avaliação do DV com óculos e com LCG, a AFO é uma medida mais sensível da função visual que a AV LogMAR de alto contraste e a SC. / Objective: to evaluate the visual performance(VP) by Visual acuity(VA)Logmar of high contrast, sensibility of contrast(SC) and wavefront (WF) in myopic patients correct with spectacles and 3 SCL Methods: prospective clinical trial was performed in 40 myopic patients(-1,00 D and -4,50 D). Exams: VA, WF and CS. Results: The WF analysis detected a significant difference in a third order aberration with and without SCL. There was significant difference related to trefoil coefficient in VP between with and without SCL. Conclusion: In VP evaluation with spectacles and SCL the wavefront analysis was more sensible measure of VP when compared with high contrast VA Logmar and CS.
142

Estudo comparativo entre a ceratectomia fotorrefrativa (PRK) e a ceratectomia subepitelial borboleta assistida a laser (LASEK borboleta) / Comparative study between photorefractive keratectomy (PRK) and butterfly laser-assisted subepithelial keratectomy (BLASEK)

Vinicius Coral Ghanem 29 August 2007 (has links)
OBJETIVO: Avaliar comparativamente os resultados de duas técnicas de cirurgia refrativa de superfície com excimer laser, ceratectomia fotorrefrativa (PRK) e ceratectomia subepitelial borboleta assistida à laser (LASEKb). LOCAL: Hospital de Olhos Sadalla Amin Ghanem, Joinville, Santa Catarina, Brasil. MÉTODOS: Realizou-se um estudo prospectivo, randomizado e duplo-cego envolvendo 102 olhos de 51 pacientes. Cada paciente teve aleatoriamente um dos olhos operado com a técnica do PRK e o outro com LASEKb. Os pacientes foram acompanhados por 1 ano. RESULTADOS: Não houveram diferenças significativas entre os dois grupos na acuidade visual (AV) para longe, sem correção, (P = 0,5593). No 12o mês pós-operatório (PO), 98,04% dos olhos no grupo do PRK e 96,08% no grupo do LASEKb atingiram AV sem correção de 20/20. A previsibilidade, eficácia, segurança e estabilidade não apresentaram diferença estatisticamente significativa entre os grupos. O índice de segurança foi de 1 no PRK e 0,996 no LASEKb. Um olho do grupo do LASEKb perdeu uma linha de visão. A porcentagem de olhos que apresentou EE aos 12 meses na faixa de ±0,50 D foi de 94,1% no grupo do PRK e de 86,3% no grupo do LASEKb (P = 0,1883). Enquanto que na faixa de ±1,0 D foi de 100% no grupo do PRK e 98% no grupo do LASEKb (P = 0,3125). Não houve necessidade de reoperações. O tempo médio de cirurgia na técnica PRK foi de 304,86 + 58,77 segundos (aproximadamente 5 minutos) e na técnica LASEKb de 608,35 + 76,88 segundos (aproximadamente 10 minutos) (P < 0,001). O tempo médio de reepitelização no grupo do PRK foi de 4,35 ± 0,48 dias (variação, 4 a 5 dias) e no grupo do BLASEK foi de 4,75 ± 0,72 dias (variação, 4 a 6 dias) (P < 0,002). Os níveis de dor e o desconforto ocular PO não foram estatisticamente diferentes entre os grupos, entretanto houve uma tendência para menor dor no PRK (3,31 ± 4,09 vs 4,43 ± 4,27; P = 0,18). Houve uma redução estatisticamente significativa nos valores do teste de Schirmer em todas as avaliação PO, tanto no PRK (23,6 ± 8,1 vs 19,4 ± 10,1; P < 0,002) quanto no LASEKb (22,4 ± 8,7 vs 18,9 ± 9,7; P = 0,01), entretanto não houve diferença entre os grupos. A opacificação corneana (OC) PO foi pequena nos dois grupos. Somente no 1o mês foi observado diferença estatística entre os grupos, com maior intensidade da OC no grupo do LASEKb (0,18 ± 0,3881) quando comparado ao PRK (0,08 ± 0,2109) (P = 0,039936). A maior intensidade foi observada no 3o mês, com redução gradativa até o 12o mês. CONCLUSÃO: Dentro das condições deste estudo, conclui-se que o PRK e o LASEKb mostraram resultados semelhantes, exceto que o PRK apresentou menor tempo cirúrgico, reepitelização corneana mais rápida e menor OC no 30o PO. / PURPOSE: Comparatively evaluate the results of two techniques of surface excimer laser refractive surgery, photorefractive keratectomy (PRK) and butterfly laser-assisted subepithelial keratectomy (BLASEK). SETTING: Sadalla Amin Ghanem Eye Hospital, Joinville, Santa Catarina, Brazil. METHODS: This is a prospective, randomized and double-masked study including 102 eyes from 51 patients. Each patient was randomized to have one eye operated on with PRK and the other with BLASEK. Patients were followed for 1 year. RESULTS: There were no significant differences between the groups regarding uncorrected distant visual acuity (VA) (p= 0.5593). On the 12th post-operative (PO) month, 98.04% of the eyes in the PRK group and 96.08% in the BLASEK group reached uncorrected VA of 20/20. The predictability, efficacy, safety and stability did not present statically significant difference between groups. The safety index was of 1 for PRK and 0.996 for BLASEK. One eye of the BLASEK group lost one line on the 12th PO month. The percentage of the eyes that presented spherical equivalent at 12 months in the range of ±0.50 D was 94.1% in the PRK group and 86.3% in the BLASEK group (p = 0.1883). While in the range of ±1.0 D it was 100% in the PRK group and 98% in the BLASEK group (p = 0.3125). There were no retreatments. The mean surgical time was 304.86 + 58.77 seconds (approximately 5 minutes) in PRK and 608.35 + 76.88 seconds in BLASEK (approximately 10 minutes) (P < 0,001). The mean reepithelization time in the PRK group was 4.35 ± 0.48 days (range, 4 to 5 days), and in the BLASEK group was 4.75 ± 0.72 days (range, 4 to 6 days) (P < 0.002). Pain scores and ocular discomfort were not statistically different between groups, although there was a trend towards a lower pain level with PRK (3.31 ± 4.09 vs. 4.43 ± 4.27; P = 0.18). Schirmer test values were significantly reduced from preoperative levels through 12 months with both PRK (23.6 ± 8.1 vs. 19.4 ± 10.1; P < 0.002) and BLASEK (22.4 ± 8.7 vs. 18.9 ± 9.7; P = 0.01), however there was no difference between groups in any time point. Haze incidence was slight in both groups. Only in the 1st PO month statistical difference between the groups was observed, with higher intensity in the BLASEK group (0.18 ± 0.3881) when compared to the PRK (0.08 ± 0.2109) (p = 0.039936). The highest intensity was observed on the 3rd month, with gradual reduction until the 12th month. CONCLUSION: In the conditions of this study, it can be concluded that PRK and BLASEK showed similar results, except that PRK presented shorter surgical time, faster corneal reepithelization and less haze at 30th PO days.
143

Reclamações trabalhistas e eficiência econômica / Labor complaints and economic efficiency

Sergio André Castelani 26 September 2008 (has links)
Esta dissertação investiga a relação entre eficiência econômica e reclamações trabalhistas. Especificamente, neste trabalho desenvolvemos um modelo teórico baseado na Teoria dos Jogos que explica o funcionamento econômico dos casos de reclamações trabalhistas, com ênfase na escolha entre soluções negociadas ou litigiosas para as mesmas. O texto dá atenção especial ao sistema existente no Brasil das Câmaras de Conciliação Prévia. Também testamos empiricamente as conclusões teóricas do modelo, para obter apoio empírico às suas previsões. Com base nas evidências obtidas, sugerimos alguns aperfeiçoamentos para melhorar o funcionamento das regras de solução das reclamações trabalhistas para extrair maior eficiência econômica destes procedimentos. / This dissertation investigates the relationship between economic efficiency and labor complaints. Specifically, this work developed a theoretical model based on Games Theory which explains the economic functioning of labor complaints cases, with emphasis on the choice between negotiated or litigant solutions to them. The text gives special attention to the existing system in Brazil called Câmaras de Conciliação Prévia (Prior Conciliation Boards). Moreover, we also have tested empirically the conclusions of the theoretical model, aiming to find empirical support to its forecasts. Based on the evidence obtained, we suggest some improvements to the functioning of the labor complaints solution rules, in order to extract greater economic efficiency from these procedures.
144

Determinants of seeking eye care services among Grade 8 to 12 learners in Giyani, South Africa

Mulungwa, Justice 05 1900 (has links)
MPH / Department of Public Health / See the attached abstract below
145

Risk Factors Associated with the Occurrence of Refractive errors among Secondary School Children in Malamulele Community, Limpopo Province.

Khoza, Hllawulani Lizzy 09 1900 (has links)
MPH / Department of Public Health / See the attached abstract below
146

Managermyopie in deutschen Unternehmen: Eine empirische Analyse

Berger, Michael 16 July 2012 (has links)
Unterlassen die Vorstände deutscher Unternehmen wirtschaftlich sinnvolle Investitionen, um einer auf Quartalszahlen fokussierten Financial Community befriedigende Ergebnisse präsentieren zu können? In der vorliegenden Arbeit wird die Frage nach der Existenz von solch kurzfristigem Verhalten, bezeichnet als Managermyopie bzw. Managerial Myopia, sowie den Einflussfaktoren auf dieses Verhalten gestellt. Zur Beantwortung wurden eine postalische, anonymisierte Fragebogenumfrage unter den Finanzvorständen der CDAX-Unternehmen mit einer Rücklaufquote von 21% sowie teilstrukturierte Interviews durchgeführt. Die Ergebnisse liefern deutliche Hinweise auf die Existenz von kurzfristigem Verhalten. Die Faktoren Kapitalmarktdruck, Unternehmensgröße und Fremdkapitalquote besitzen einen statistisch messbaren Einfluss auf kurzfristiges Verhalten. Die Untersuchung liefert direkte Erkenntnisse über Kapitalmarktdruck, das tatsächlich ausgeübte Maß von kurzfristigem Verhalten und die aktuelle Debatte über die verpflichtende Einführung von Quartalsberichterstattung.:INHALTSVERZEICHNIS I ABKÜRZUNGSVERZEICHNIS IV ABBILDUNGSVERZEICHNIS VI TABELLENVERZEICHNIS VII I. EINLEITUNG 1 1. HINTERGRUND 1 2. PROBLEMSTELLUNG, RELEVANZ UND NEUIGKEITSGRAD DER ARBEIT 3 3. AUFBAU DER ARBEIT 5 II. GRUNDLAGEN 7 1. MANAGERMYOPIE: BEGRIFFSBESTIMMUNG 7 2. AUSPRÄGUNGSFORMEN VON MANAGERMYOPIE 11 2.1. Aufwendungsmyopie 12 2.1.1. Forschung und Entwicklung 13 2.1.2. Werbung 14 2.1.3. Personalentwicklung 16 2.1.4. Sonstige Ausprägungsformen von Aufwendungsmyopie 17 2.2. Ertragsmyopie 17 2.2.1. Preiserhöhungen 18 2.2.2. Preissenkungen 19 2.2.3. Markenerweiterungen 22 2.2.4. Nutzung neuer Distributionskanäle 23 III. LITERATURÜBERBLICK 26 1. EINORDNUNG DER MANAGERMYOPIE-LITERATUR INNERHALB DER CORPORATE-FINANCE-LITERATUR 26 2. EINORDNUNG DER MANAGERMYOPIE-LITERATUR INNERHALB DER ACCOUNTING-LITERATUR 33 2.1. Einordnung der Managermyopie-Literatur innerhalb der angloamerikanischen Accounting-Literatur 33 2.2. Einordnung der Managermyopie-Literatur innerhalb der deutschen Accounting-Literatur 35 3. „ANECDOTAL EVIDENCE“ 37 4. THEORETISCHE ARBEITEN 42 5. EMPIRISCHE ARBEITEN 53 5.1. Analysen von Aufwendungen 53 5.2. Analysen von Kapitalaufnahmen 58 5.3. Umfragen und Experimente 62 5.4. Sonstige 64 6. ZUSAMMENFASSENDE WÜRDIGUNG DES VORHANDENEN MATERIALS 69 6.1. Würdigung des vorhandenen theoretischen Materials 69 6.2. Würdigung des vorhandenen empirischen Materials 71 IV. METHODIK 74 1. FRAGESTELLUNGEN UND HYPOTHESEN 74 1.1. Fragestellungen 75 1.1.1. Existenz von Managermyopie in deutschen Unternehmen 76 1.1.2. Existenz von Kapitalmarktdruck auf deutsche Unternehmen 79 1.2. Hypothesen 80 1.2.1. Kapitalmarktdruck 81 1.2.2. Berichtsfrequenz 82 1.2.3. Strategische Langfristinvestoren 84 1.2.4. Fremdfinanzierung 85 1.2.5. Unternehmensgröße 86 1.2.6. Industriezugehörigkeit 87 2. DURCHFÜHRUNG DER UNTERSUCHUNG 88 2.1. Methode der Datenerhebung 88 2.1.1. Begründung der Methode der Datenerhebung 88 2.1.2. Einordnung des gewählten Untersuchungsdesigns 91 2.2. Durchführung der Fragebogenumfrage 93 2.2.1. Untersuchungsobjekte, angestrebte Grundgesamtheit und Beobachtungsobjekte 93 2.2.2. Auswahlgesamtheit 94 2.2.3. Fragebogenentwicklung 95 2.2.4. Versendung und Rücklauf der Fragebögen, Inferenzpopulation 96 2.3. Durchführung der Interviewserie 98 2.4. Operationalisierung der verwendeten Variablen 99 2.4.1. Operationalisierung von Managermyopie 99 2.4.2. Operationalisierung von Kapitalmarktdruck 103 2.4.3. Operationalisierung der demographischen Variablen 104 3. BESCHREIBUNG DER INFERENZPOPULATION DER FRAGEBOGENUMFRAGE 107 3.1. Eigenschaften der an der Fragebogenumfrage teilnehmenden Unternehmen 107 3.2. Verzerrungen der Inferenzpopulation 109 3.2.1. Analyse des Coverage-Bias 109 3.2.2. Analyse des Non-Response-Bias 110 3.2.3. Analyse des Social-Desirability-Bias 114 3.2.4. Analyse des Informant-Bias 117 3.2.5. Analyse der Verzerrung durch Mißverständnis 118 4. ZUSAMMENFASSUNG DER METHODIK 119 V. ERGEBNISSE 122 1. DESKRIPTIVE ANALYSE 122 1.1. Existenz von Managermyopie in deutschen Unternehmen 122 1.2. Existenz von Aufwendungsmyopie in deutschen Unternehmen 124 1.3. Existenz verschiedener Ausprägungen von Aufwendungsmyopie in deutschen Unternehmen 126 1.4. Existenz von Ertragsmyopie in deutschen Unternehmen 128 1.5. Existenz verschiedener Ausprägungen von Ertragsmyopie in deutschen Unternehmen 129 1.6. Existenz von Kapitalmarktdruck in deutschen Unternehmen 131 2. INFERENZSTATISTISCHE ANALYSE 133 2.1. Kapitalmarktdruck und Managermyopie 133 2.2. Berichtsfrequenz und Kapitalmarktdruck 137 2.3. Berichtsfrequenz und Managermyopie 139 2.4. Strategische Langfristinvestoren und Kapitalmarktdruck 140 2.5. Strategische Langfristinvestoren und Managermyopie 141 2.6. Fremdkapitalquote und Kapitalmarktdruck 142 2.7. Fremdkapitalquote und Managermyopie 144 2.8. Unternehmensgröße und Kapitalmarktdruck 145 2.9. Unternehmensgröße und Managermyopie 147 2.10. Industriezugehörigkeit und Kapitalmarktdruck 148 2.11. Industriezugehörigkeit und Managermyopie 152 VI. DISKUSSION UND AUSBLICK 156 1. ZUSAMMENFASSUNG UND DISKUSSION DER ERGEBNISSE 156 2. FAZIT 162 3. LIMITATIONEN DER VORLIEGENDEN ARBEIT 163 4. STÄRKEN DER VORLIEGENDEN ARBEIT 164 5. ZUKÜNFTIGE FORSCHUNG 165 6. AUSBLICK 167 ANHANG 1: DAS MODELL VON STEIN (1989) 170 ANHANG 2: FRAGEBOGEN 174 ANHANG 3: BEGLEITSCHREIBEN DEUTSCHE BÖRSE AG 176 ANHANG 4: ANTWORTEN DER FRAGEBOGENUMFRAGE 177 ANHANG 5: INTERVIEW-LEITFADEN 178 LITERATURVERZEICHNIS 180 VERZEICHNIS DER ZITIERTEN ZEITUNGSARTIKEL 199 VERZEICHNIS DER ZITIERTEN GESETZE UND VERORDNUNGEN 200
147

Influence of eye rotation on peripheral eye length measurement obtained with a partial coherence interferometry instrument

Verkicharla, P.K., Suheimat, M., Mallen, Edward A.H., Atchison, D.A. 11 December 2013 (has links)
No / The eye rotation approach for measuring peripheral eye length leads to concern about whether the rotation influences results, such as through pressure exerted by eyelids or extra-ocular muscles. This study investigated whether this approach is valid. Peripheral eye lengths were measured with a Lenstar LS 900 biometer for eye rotation and no-eye rotation conditions (head rotation for horizontal meridian and instrument rotation for vertical meridian). Measurements were made for 23 healthy young adults along the horizontal visual field (+/- 30 degrees ) and, for a subset of eight participants along the vertical visual field (+/- 25 degrees ). To investigate the influence of the duration of eye rotation, for six participants measurements were made at 0, 60, 120, 180 and 210 s after eye rotation to +/- 30 degrees along horizontal and vertical visual fields. Peripheral eye lengths were not significantly different for the conditions along the vertical meridian (F1,7 = 0.16, p = 0.71). The peripheral eye lengths for the conditions were significantly different along the horizontal meridian (F1,22 = 4.85, p = 0.04), although not at individual positions (p >/= 0.10) and were not important. There were no apparent differences between the emmetropic and myopic groups. There was no significant change in eye length at any position after maintaining position for 210 s. Eye rotation and no-eye rotation conditions were similar for measuring peripheral eye lengths along horizontal and vertical visual field meridians at +/- 30 degrees and +/- 25 degrees , respectively. Either condition can be used to estimate retinal shape from peripheral eye lengths.
148

Ocular rigidity : a previously unexplored risk factor in the pathophysiology of open-angle glaucoma : assessment using a novel OCT-based measurement method

Sayah, Diane Noël 02 1900 (has links)
Le glaucome est la première cause de cécité irréversible dans le monde. Bien que sa pathogenèse demeure encore nébuleuse, les propriétés biomécaniques de l’oeil sembleraient jouer un rôle important dans le développement et la progression de cette maladie. Il est stipulé que la rigidité oculaire (RO) est altérée au travers les divers stades de la maladie et qu’elle serait le facteur le plus influent sur la réponse du nerf optique aux variations de la pression intraoculaire (PIO) au sein du glaucome. Pour permettre l’investigation du rôle de la RO dans le glaucome primaire à angle ouvert (GPAO), la capacité de quantifier la RO in vivo par l’entremise d’une méthode fiable et non-invasive est essentielle. Une telle méthode n’est disponible que depuis 2015. Basée sur l'équation de Friedenwald, cette approche combine l'imagerie par tomographie par cohérence optique (TCO) et la segmentation choroïdienne automatisée afin de mesurer le changement de volume choroïdien pulsatile (ΔV), ainsi que la tonométrie dynamique de contour Pascal pour mesurer le changement de pression pulsatile correspondant. L’objectif de cette thèse est d’évaluer la validité de cette méthode, et d’en faire usage afin d’investiguer le rôle de la RO dans les maladies oculaires, particulièrement le GPAO. Plus spécifiquement, cette thèse vise à : 1) améliorer la méthode proposée et évaluer sa validité ainsi que sa répétabilité, 2) investiguer l’association entre la RO et le dommage neuro-rétinien chez les patients glaucomateux, et ceux atteints d’un syndrome de vasospasticité, 3) évaluer l’association entre la RO et les paramètres biomécaniques de la cornée, 4) évaluer l’association entre la RO et les pics de PIO survenant suite aux thérapies par injections intravitréennes (IIV), afin de les prédire et de les prévenir chez les patients à haut risque, et 5) confirmer que la RO est réduite dans les yeux myopes. D’abord, nous avons amélioré le modèle mathématique de l’oeil utilisé pour dériver ΔV en le rendant plus précis anatomiquement et en tenant compte de la choroïde périphérique. Nous avons démontré la validité et la bonne répétabilité de cette méthodologie. Puis, nous avons effectué la mesure des coefficients de RO sur un large éventail de sujets sains et glaucomateux en utilisant notre méthode non-invasive, et avons démontré, pour la première fois, qu'une RO basse est corrélée aux dommages glaucomateux. Les corrélations observées étaient comparables à celles obtenues avec des facteurs de risque reconnus tels que la PIO maximale. Une forte corrélation entre la RO et les dommages neuro-rétiniens a été observée chez les patients vasospastiques, mais pas chez ceux atteints d'une maladie vasculaire ischémique. Cela pourrait potentiellement indiquer une plus grande susceptibilité au glaucome due à la biomécanique oculaire chez les patients vasospastiques. Bien que les paramètres biomécaniques cornéens aient été largement adoptés dans la pratique clinique en tant que substitut pour la RO, propriété biomécanique globale de l'oeil, nous avons démontré une association limitée entre la RO et ces paramètres, offrant une nouvelle perspective sur la relation entre les propriétés biomécaniques cornéennes et globales de l’oeil. Seule une faible corrélation entre le facteur de résistance cornéenne et la RO demeure après ajustement pour les facteurs de confusion dans le groupe des patients glaucomateux. Ensuite, nous avons présenté un modèle pour prédire l'amplitude des pics de PIO après IIV à partir de la mesure non-invasive de la RO. Ceci est particulièrement utile pour les patients à haut risque atteints de maladies rétiniennes exsudatives et de glaucome qui nécessiteraient des IIV thérapeutiques, et pourrait permettre aux cliniciens d'ajuster ou de personnaliser le traitement pour éviter toute perte de vision additionnelle. Enfin, nous avons étudié les différences de RO entre les yeux myopes et les non-myopes en utilisant cette technique, et avons démontré une RO inférieure dans la myopie axiale, facteur de risque du GPAO. Dans l'ensemble, ces résultats contribuent à l’avancement des connaissances sur la physiopathologie du GPAO. Le développement de notre méthode permettra non seulement de mieux explorer le rôle de la RO dans les maladies oculaires, mais contribuera également à élucider les mécanismes et développer de nouveaux traitements ciblant la RO pour contrer la déficience visuelle liée à ces maladies. / Glaucoma is the leading cause of irreversible blindness worldwide. While its pathogenesis is yet to be fully understood, the biomechanical properties of the eye are thought to be involved in the development and progression of this disease. Ocular rigidity (OR) is thought to be altered through disease processes and has been suggested to be the most influential factor on the optic nerve head’s response to variations in intraocular pressure (IOP) in glaucoma. To further investigate the role of OR in open-angle glaucoma (OAG) and other ocular diseases such as myopia, the ability to quantify OR in living human eyes using a reliable and non-invasive method is essential. Such a method has only become available in 2015. Based on the Friedenwald equation, the method uses time-lapse optical coherence tomography (OCT) imaging and automated choroidal segmentation to measure the pulsatile choroidal volume change (ΔV), and Pascal dynamic contour tonometry to measure the corresponding pulsatile pressure change. The purpose of this thesis work was to assess the validity of the methodology, then use it to investigate the role of OR in ocular diseases, particularly in OAG. More specifically, the objectives were: 1) To improve the extrapolation of ΔV and evaluate the method’s validity and repeatability, 2) To investigate the association between OR and neuro-retinal damage in glaucomatous patients, as well as those with concomitant vasospasticity, 3) To evaluate the association between OR and corneal biomechanical parameters, 4) To assess the association between OR and IOP spikes following therapeutic intravitreal injections (IVIs), to predict and prevent them in high-risk patients, and 5) To confirm that OR is lower in myopia. First, we improved the mathematical model of the eye used to derive ΔV by rendering it more anatomically accurate and accounting for the peripheral choroid. We also confirmed the validity and good repeatability of the method. We carried out the measurement of OR coefficients on a wide range of healthy and glaucomatous subjects using this non-invasive method, and were able to show, for the first time, that lower OR is correlated with more glaucomatous damage. The correlations observed were comparable to those obtained with recognized risk factors such as maximum IOP. A strong correlation between OR and neuro-retinal damage was found in patients with concurrent vasospastic syndrome, but not in those with ischemic vascular disease. This could perhaps indicate a greater susceptibility to glaucoma due to ocular biomechanics in vasospastic patients. While corneal biomechanical parameters have been widely adopted in clinical practice as surrogate measurements for the eye’s overall biomechanical properties represented by OR, we have shown a limited association between these parameters, bringing new insight unto the relationship between corneal and global biomechanical properties. Only a weak correlation between the corneal resistance factor and OR remained in glaucomatous eyes after adjusting for confounding factors. In addition, we presented a model to predict the magnitude of IOP spikes following IVIs from the non-invasive measurement of OR. This is particularly useful for high-risk patients with exudative retinal diseases and glaucoma that require therapeutic IVIs, and could provide the clinician an opportunity to adjust or customize treatment to prevent further vision loss. Finally, we investigated OR differences between non-myopic and myopic eyes using this technique, and demonstrated lower OR in axial myopia, a risk factor for OAG. Overall, these findings provide new insights unto the pathophysiology of glaucomatous optic neuropathy. The development of our method will permit further investigation of the role of OR in ocular diseases, contributing to elucidate mechanisms and provide novel management options to counter vision impairment caused by these diseases.

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