Urea-De-Epithelialized Human Amniotic Membrane for Ocular Surface Reconstruction.

The conjunctiva is a clear tissue covering the white part of the eye and lines the back of the eyelids. Conjunctival diseases, such as symblepharon, cause inflammation, discharges, and photophobia. The treatment often requires excision of large parts of conjunctiva. Tissue engineering of conjunctival cells using human amniotic membrane (HAM) denuded of its epithelium as a basement membrane scaffold has been shown to be effective for covering conjunctival defects. However, most epithelial denudation protocols are time-consuming and expensive or compromise HAM's basement membrane structure and matrix components. We have previously described a method to de-epithelialize HAM using ice-cold urea (uHAM). In this report, we used this method to provide tissue-engineered constructs with cultivated conjunctival epithelial cells on uHAM in two patients, one with a giant conjunctival nevus and the other with a large symblepharon. Autologous conjunctival epithelial cells harvested from incisional biopsies of these two patients were cultured on the uHAM scaffold. The transplantation of tissue-engineered constructs to patients' ocular surface immediately after the removal of lesions showed successful reconstruction of the ocular surface. Postoperatively, there were neither recurrence of lesions nor epithelial defects throughout the follow-up (up to 7 and 19 months, respectively). This report highlights the translational potential of an efficient and inexpensive method to prepare de-epithelialized HAM as a basement membrane scaffold for cell-based tissue-engineered treatments of ocular surface disorders. Stem Cells Translational Medicine 2019;8:620&626.

Prospective audit of ptosis surgery at the Singapore National Eye Centre: two-year results.

PURPOSE: To evaluate the demographics, presentation, and surgical outcomes of patients undergoing ptosis surgery in an Asian population in a prospective manner. METHODS: A prospective ptosis audit was conducted over a 2-year period from January 2010 to December 2011 in a tertiary eye hospital in Singapore. All patients undergoing ptosis surgery by, or under the supervision of, an oculoplastic-trained consultant in the institution were included. Institutional Review Board approval was obtained for the study. RESULTS: This study comprises 302 patients, of which 236 were acquired and 66 were congenital ptosis cases. Levator repair (77.2%) was the most commonly performed procedure, followed by levator resection (13.9%) and brow suspension (8.9%). Forty-seven (10.1%) eyes had readjustment within 2 weeks, the reasons for readjustment being eyelid height undercorrection (n = 35), eyelid height overcorrection (n = 9), and unsatisfactory eyelid contour (n = 4). Postoperatively, 93.8% of patients showed an increase in marginal reflex distance-1 (MRD1), 91.3% achieved symmetry or <1 mm of asymmetry in MRD1, 98.5% had good eyelid contour, and 74.3% had symmetric eyelid crease. On a scale of 1 to 10, 83.1% of patients gave a subjective grade of 7 or better. CONCLUSIONS: This study is the first prospective ptosis surgery audit in an Asian population and takes a leading step in assessing both subjective and objective surgical outcomes in a prospective manner. With the continuation of this audit in years to come, it will allow us to generate clinical outcomes in a robust manner and allow for more reliable benchmarking with major centers elsewhere.

Variation of angle parameters in asians: an anterior segment optical coherence tomography study in a population of singapore malays.

PURPOSE: To assess variations in angle parameters using anterior segment optical coherence tomography (AS-OCT) and to investigate demographic, ocular and systemic associations of angle width. METHODS: This was a substudy of a population based, cross-sectional survey of 3280 (78.7% response rate) Malay people aged 40 to 80 years in Singapore. All participants underwent a standardized interview and ocular and systemic examination. AS-OCT was performed on 291 consecutive patients in standardized dark conditions. Angle opening distance (AOD-500) and trabecular-iris space area (TISA-500) 500 microm from the scleral spur were determined for the nasal and temporal angles. Anterior chamber depth (ACD) was also measured. RESULTS: AS-OCT measurements were analyzed in 239 (82.1%) right eyes. Mean AOD 500 was smaller in women than in men, both nasally (0.255 vs. 0.293 mm, P = 0.026) and temporally (0.245 vs. 0.286 mm, P = 0.023). Mean TISA-500 was smaller in women in the nasal quadrant only (0.104 vs. 0.117 mm, P = 0.035). Mean ACD was smaller in women than in men (2.71 vs. 2.87 mm, P = 0.001). Multiple linear regression showed that axial length and ACD were significantly associated with AOD-500 and TISA-500 both nasally (adjusted R(2) = 0.34 for AOD-500 and 0.20 for TISA-500) and temporally (adjusted R(2) = 0.35 for AOD-500 and 0.24 for TISA-500). Body mass index, HbA(1c), systolic blood pressure, intraocular pressure, cup-to-disc ratio, and central corneal thickness were not significantly associated with AOD-500, TISA-500, or ACD. CONCLUSIONS: In this Malay population, angle width measured by AS-OCT was smaller in women than in men, and in eyes with shorter axial length and shallower ACD.

Determinants of the optic cup to disc ratio in an Asian population: the Singapore Malay Eye Study (SiMES).

OBJECTIVE: To describe the distribution and determinants of the optic cup to disc ratio (CDR) in Malay adults in Singapore. METHODS: This population-based, age-stratified study examined 3280 Malay people aged 40 to 80 years in Singapore. Participants underwent a standardized interview and an ocular examination. A slitlamp examination measured the vertical dimensions of the disc and cup, excluding areas of peripapillary atrophy and the Elschnig scleral ring. RESULTS: Vertical CDR was recorded for 3228 right eyes and 3237 left eyes. The mean (SD) CDR was 0.40 (0.15) in both eyes. The CDR in the right eye increased with age (P < .001) and was greater in men vs women (age-adjusted CDR, 0.42 vs 0.39; P < .001). In multiple linear regression, significant determinants of greater CDR were increasing age, male sex, higher intraocular pressure (IOP), lower diastolic blood pressure, lower body mass index, and previous cataract surgery. Of these, higher IOP was the most important determinant of the CDR. After excluding 149 persons with glaucoma, male sex, higher IOP, lower diastolic blood pressure, lower body mass index, and diabetes mellitus were significant predictors of greater CDR. CONCLUSION: Greater vertical CDR was related to male sex, higher IOP, lower diastolic blood pressure, and lower body mass index.

The prevalence and types of glaucoma in malay people: the Singapore Malay eye study.

PURPOSE: To assess the prevalence and types of glaucoma in an Asian Malay population. METHODS: The Singapore Malay Eye Study is a population-based, cross-sectional survey that examined 3280 (78.7% response) persons aged 40 to 80 years. Participants underwent a standardized clinical examination including slit-lamp biomicroscopy, Goldmann applanation tonometry, and dilated optic disc assessment. Participants who were suspected to have glaucoma also underwent visual field examination (24-2 SITA standard, Humphrey Visual Field Analyzer II), gonioscopy, and repeat applanation tonometry. Glaucoma was defined according to International Society for Geographical and Epidemiologic Ophthalmology criteria. RESULTS: Of the 3280 participants, 150 (4.6%) had diagnosed glaucoma, giving an age- and sex-standardized prevalence of 3.4% (95% confidence interval [CI], 3.3%-3.5%). The age- and sex-standardized prevalence of primary open-angle glaucoma was 2.5% (95% CI, 2.4%-2.6%), primary angle-closure glaucoma 0.12% (95% CI, 0.10%-0.14%), and secondary glaucoma 0.61% (95% CI, 0.59%-0.63%). Of the 150 glaucoma cases, only 12 (8%) had a previous known history of glaucoma. Twenty-seven (18%) eyes had low vision (based on best corrected visual acuity logarithm of the minimal angle of resolution [logMAR] >0.30 to <1.00 in the eye with glaucoma for unilateral cases; and based on the better eye for bilateral cases) and 15 (10%) were blind (logMAR, >/=1.00). CONCLUSIONS: The prevalence of glaucoma among Malay persons 40 years of age and older in Singapore is 3.4%, comparable to ethnic Chinese people in Singapore and other racial/ethnic groups in Asia. As in Chinese, Caucasians, and African people, primary open-angle glaucoma was the main form of glaucoma in this population. More than 90% of glaucoma cases were previously undetected.

Diabetes, hyperglycemia, and central corneal thickness: the Singapore Malay Eye Study.

PURPOSE: To examine the relationship of diabetes and hyperglycemia with central corneal thickness (CCT) in Malay adults in Singapore. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Three thousand two hundred eighty Malay adults ages 40-80 years living in Singapore. METHODS: The study population was selected using an age-stratified random sampling procedure of Malay 40- to 80-year-olds living in the southwestern part of Singapore. Participants had a standardized interview, examination, and ocular imaging at a centralized study clinic. Central corneal thickness was measured with an ultrasound pachymeter, and nonfasting serum glucose and glycosylated hemoglobin (Hb A(1C)) was obtained from all participants. Diabetes was defined as having nonfasting glucose levels of > or =200 mg/dl (11.1 mmol/l), a self-report of diabetic medication use, or physician diagnosis of diabetes. MAIN OUTCOME MEASURES: Central corneal thickness. RESULTS: Of the 3280 (78.7% response) participants, data on CCT were available on 3239 right eyes. Central corneal thickness was normally distributed, with a mean of 541.2 microm. There were 748 persons with diabetes (23.0%). After controlling for age and gender, central corneas were significantly thicker in persons with diabetes than in those without diabetes (547.2 microm vs. 539.3 microm, P<0.001) and, in the total population, with higher serum glucose (539.6, 540.2, 541.3, and 544.4, comparing increasing glucose quartiles; P = 0.023) and higher Hb A(1C) (537.8, 541.0, 541.4, and 545.5, comparing increasing Hb A(1C) quartiles; P<0.001) levels. In multiple linear regression models adjusting for age, intraocular pressure (IOP), body mass index, and axial length, persons with diabetes had, on average, central corneas 6.50 microm thicker than those of persons without diabetes. CONCLUSIONS: This population-based study among Malays showed that diabetes and hyperglycemia are associated with thicker central corneas, independent of age and IOP levels. These findings may have implications for understanding the relationship between diabetes and glaucoma.

Changes in the optic disc after acute primary angle closure.

PURPOSE: To evaluate the changes in optic disc morphology in the first 4 months after an episode of acute primary angle closure (APAC) using stereoscopic optic disc photography and computer-assisted planimetry. DESIGN: Prospective observational case series. PARTICIPANTS: Forty-seven Asian subjects with unilateral APAC who were successfully treated with laser peripheral iridotomy (LPI). MAIN OUTCOME MEASURES: Cup-to-disc ratio (CDR) and optic cup and neuroretinal rim areas. METHODS: Stereoscopic optic disc photographs were taken 2 and 16 weeks after LPI, and the images were analyzed by computer-assisted planimetry. The overall, quadrantic, and 30 degrees sector areas of the optic disc, CDR, and neuroretinal rim area were analyzed by 2 independent masked graders, and the mean of the readings was used to calculate changes in optic disc parameters. RESULTS: The majority of the subjects were female (66%) and Chinese (90%), and the mean age was 67.6+/-11.2 years (range, 40-94). In APAC eyes from week 2 to week 16, the mean CDR increased from 0.56+/-0.05 to 0.59+/-0.03 (P<0.001), and the mean neuroretinal rim area decreased from 1.74+/-0.31 mm2 to 1.59+/-0.27 mm2 (P<0.001). Quadrantic and sector analysis showed preferential loss of neuroretinal rim area at the superotemporal and inferotemporal areas. There was no significant change in optic disc parameters in the fellow eyes over the study period. CONCLUSIONS: This study demonstrated changes in optic disc morphology from week 2 to week 16 after an episode of APAC. The pattern of optic nerve damage demonstrated in our study was comparable with that seen in primary open-angle glaucoma and experimental glaucoma models.

Necrotizing scleritis following diode laser transscleral cyclophotocoagulation.

A 23-year-old Chinese woman presented with necrotizing scleritis 10 months after diode laser cyclophotocoagulation for the treatment of her neovascular glaucoma. There were areas of scleral thinning with uveal prolapse in the superior quadrant. The inflammation and progression of the staphyloma were controlled with systemic steroids. Diode laser cyclophotocoagulation may not be safe in patients suspected to have underlying systemic vasculitic diseases.