Xu Li. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 204-242). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Lai Shiu-Ming, Jimmy. / "January 2004." / Thesis (M.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 157-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.

<p>Glaucoma is a common disease in the elderly population. Open-angle glaucoma (OAG) is the predominant form of glaucoma. Chronic simple glaucoma and capsular glaucoma, characterized by the occurrence of pseudoexfoliation in the anterior eye segment, are the most frequent types of OAG. The purpose of the present thesis was to study the epidemiology of OAG in the municipality of Tierp, whose population has a high exposure to pseudoexfoliation.</p><p>In a case-finding study, the prevalence of known cases of OAG by December 31, 1983 was estimated to 1.4% in people ≥45 years of age. Sixty-three percent of all cases had capsular glaucoma. Patients with advanced glaucoma were older, had had the disease for longer, had higher mean initial intraocular pressure, and had more extensive visual field defects at the time of diagnosis.</p><p>A population survey of people 65–74 years of age was conducted in 1984–86. The prevalence of OAG was 5.3%. Pseudoexfoliation was found in 17%, being more common in females. Pseudoexfoliation was associated with OAG only in people previously diagnosed with the disease (odds ratio = 16). In cases detected at the survey, an intraocular pressure ≥20 mmHg was a serious risk factor of having OAG (odds ratio = 9.7).</p><p>In a 5-year follow-up study of participants in the population survey, increased intraocular pressure and pseudoexfoliation were recognized as independent risk factors for the development of OAG (standardized risk ratios = 3.4 and 9.8, respectively). Interaction between increased intraocular pressure and pseudoexfoliation was indicated. By May 2006, the incidence of OAG was estimated to 7.1 per 1,000 person-years. The incidence of capsular glaucoma was more than twice that of chronic simple glaucoma.</p><p>The prevalence and incidence of OAG was higher than that reported from other studies conducted on Caucasian populations. The probable explanation for this finding is exposure to pseudoexfoliation.</p>

Glaucoma is a common disease in the elderly population. Open-angle glaucoma (OAG) is the predominant form of glaucoma. Chronic simple glaucoma and capsular glaucoma, characterized by the occurrence of pseudoexfoliation in the anterior eye segment, are the most frequent types of OAG. The purpose of the present thesis was to study the epidemiology of OAG in the municipality of Tierp, whose population has a high exposure to pseudoexfoliation. In a case-finding study, the prevalence of known cases of OAG by December 31, 1983 was estimated to 1.4% in people ≥45 years of age. Sixty-three percent of all cases had capsular glaucoma. Patients with advanced glaucoma were older, had had the disease for longer, had higher mean initial intraocular pressure, and had more extensive visual field defects at the time of diagnosis. A population survey of people 65–74 years of age was conducted in 1984–86. The prevalence of OAG was 5.3%. Pseudoexfoliation was found in 17%, being more common in females. Pseudoexfoliation was associated with OAG only in people previously diagnosed with the disease (odds ratio = 16). In cases detected at the survey, an intraocular pressure ≥20 mmHg was a serious risk factor of having OAG (odds ratio = 9.7). In a 5-year follow-up study of participants in the population survey, increased intraocular pressure and pseudoexfoliation were recognized as independent risk factors for the development of OAG (standardized risk ratios = 3.4 and 9.8, respectively). Interaction between increased intraocular pressure and pseudoexfoliation was indicated. By May 2006, the incidence of OAG was estimated to 7.1 per 1,000 person-years. The incidence of capsular glaucoma was more than twice that of chronic simple glaucoma. The prevalence and incidence of OAG was higher than that reported from other studies conducted on Caucasian populations. The probable explanation for this finding is exposure to pseudoexfoliation.

No description available.

Epidemiological evidence indicates that selenium supplementation may increase risk for ocular hypertension and glaucoma. The purpose of this project was to determine the effects of selenium on the conventional "trabecular" aqueous outflow pathway, a likely site of pathology for glaucoma. Human trabecular meshwork (HTM) cells and human umbilical vein endothelial cells (HUVECs) were treated with selenium (MSeA) at or near physiologically relevant concentrations. Selenium uptake by cells was monitored using mass spectrometry. While detectible changes in intracellular selenium were observed after exposure to 1-10 uM MSeA for 24 hours, the majority remained in the conditioned medium. The high concentrations of extracellular selenium we observed raised the possibility that selenium has an extracellular target.To investigate the role of selenium in extracellular matrix turnover, I examined alterations in protein secretion and intracellular signaling. MSeA treatment (5-10 uM) led to a significant decrease in the secretion of matrix metalloproteinase -2 and its inhibitor after 6-24 hours and to a dose-dependent decrease in kinase signaling. Later, I investigated the possibility that integrins are an extracellular target of selenium by monitoring morphological changes in HTM cells and by treating them with divalent cations. MSeA stimulated morphological changes consistent with a decrease in integrin function. These occurred before (less than 3 hours) alterations in protein secretion and intracellular signaling (3-6 hours). Zinc treatment prevented MSeA-mediated alterations in protein secretion and changes in cell-matrix adhesion.Finally markers of HTM cell homeostasis were examined. MSeA treatment (5 uM) led to a 60% decrease in protein synthesis after 3 hours and a 60% reduction in protein secretion, without causing significant alterations in cell viability and total ATP. To assess the physiological relevance of my results, anterior segments were perfused with MSeA to determine its effects on aqueous outflow facility. Preliminary results suggest that MSeA leads to a decrease in outflow facility.The combination of MSeA-induced decreases in several indicators of HTM cell homeostasis (without adversely effects on cell viability at physiologically relevant doses) and decreases in outflow facility provide a possible mechanism for selenium-associated ocular hypertension.

No description available.

El presente trabajo es una adaptación de la técnica quirúrgica de trabeculectomía para el tratamiento del glaucoma canino. Para tal fin se utilizaron 5 caninos de distintos sexos, razas y edades, con una historia clínica de glaucoma. Ellos fueron intervenidos en la Clínica de Animales Menores de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos, empleándose la técnica quirúrgica de trabeculectomía, la cual consiste en crear una nueva vía de drenaje del humor acuoso. En cada uno de los casos, se demostró que dicha técnica es una alternativa, rápida, poco costosa y confiable para el tratamiento resolutivo de esta patología. Con el fin de verificar su eficacia se realizaron evaluaciones oftalmológicas post-quirúrgicas. Los hallazgos mostraron en todos los casos una importante disminución de la presión intraocular. Al comparar las presiones intraoculares antes y después de la intervención quirúrgica se encontró una diferencia estadística significativa con un nivel de confiabilidad del 99%. Se concluye que la técnica quirúrgica de trabeculectomía puede ser usada en la resolución del aumento de la presión intraocular en caninos. / The present work in an adjustment of the surgical technique of trabeculectomy for the treatment of the canine glaucoma. To accomplish it, 5 canines of different sex, races and age, with clinical history of glaucoma were used. They were treated in the Clinic of Small Animals of the Faculty of Veterinary Medicine of the National University of San Marcos. The surgical technique of trabeculectomy permitted to find a new way of draining of the aqueous humor. In each of the cases, there was demonstrated that the technique is a quick, cheap and reliable alternative for treatment of this pathology. In order to verify its efficiency, postsurgical evaluations were done. In all the case the findings showed an important decrease of the intraocular pressure. When comparing the intraocular pressures before an after the surgical intervention. There was found a significative statistical difference, with 99% of reliance. It is concluded that the surgical technique of trabeculectomy can be used successfully in the treatment of the increase of he intraocular pressure in canine.

Purpose: We evaluate solutions for an applanating surface modification to the Goldmann tonometer prism, which substantially negates the errors due to patient variability in biomechanics. Methods: A modified Goldmann or correcting applanation tonometry surface (CATS) prism is presented which was optimized to minimize the intraocular pressure (lOP) error due to corneal thickness, stiffness, curvature, and tear film. Mathematical modeling with finite element analysis (FEA) and manometric lOP referenced cadaver eyes were used to optimize and validate the design. Results: Mathematical modeling of the optimized CATS prism indicates an approximate 50% reduction in each of the corneal biomechanical and tear film errors. Manometric lOP referenced pressure in cadaveric eyes demonstrates substantial equivalence to GAT in nominal eyes with the CATS prism as predicted by modeling theory. Conclusion: A CATS modified Goldmann prism is theoretically able to significantly improve the accuracy of lOP measurement without changing Goldmann measurement technique or interpretation. Clinical validation is needed but the analysis indicates a reduction in CCT error alone to less than +/- 2 mm Hg using the CATS prism in 100% of a standard population compared to only 54% less than +/- 2 mm Hg error with the present Goldmann prism. Translational Relevance: This article presents an easily adopted novel approach and critical design parameters to improve the accuracy of a Goldmann applanating tonometer.

Purpose: To compare the effect of topical prednisolone acetate 1% (PA) used after routine cataract surgery to the effect of difluprednate 0.05% (DFBA) used for the same indication on intraocular pressure (IOP). Methods: An electronic query was created to gather information from all cataract surgeries between January 2010 and January 2015 within the electronic health record database at Barnet Dulaney Perkins, a multicenter, multiphysician private practice in Phoenix, Arizona. Information collected included age, sex, diabetes status, glaucoma history, medication regimen (use of PA or DFBA), and IOP before surgery, 5-10 days postoperatively (TP1) and 3-6 weeks postoperatively (TP2). Postoperative IOP measurements were compared to baseline IOP measurement in each patient. Results: Regardless of steroid used, all patients in this study experienced an increase in IOP within TP1 and returned to baseline IOP (+/- 2.0 mmHg) by TP2. Patients who received DFBA showed a statistically significant increase in IOP at TP1 compared to those on PA (P<0.001) with the mean IOP an average 0.60 mmHg higher (95% CI = 0.3, 0.9). The odds ratio of a clinically significantly increased IOP at TP1 (defined as overall IOP >= 21 mmHg and an increase of >= 10 mmHg) in DFBA-treated patients was 1.84 (95% CI = 1.4, 2.6). In patients treated with PA, 3% reached a significantly increased IOP, compared to 4.4% of patients in the DFBA group (P<0.05). Risk factors for increased IOP were identified, and include advanced age (>75) (P<0.005) and a history of glaucoma (P<0.001). Conclusion: In postoperative cataract patients, use of DFBA increased the risk of a clinically significant IOP increase.