Biomedical subjects

Tin Aung

Publications and source records attributed to Tin Aung.

At least 19 recordsLinked to original sources

PubMed2006

Comparison of the scanning peripheral anterior chamber depth analyzer and the modified van Herick grading system in the assessment of angle closure.

PURPOSE: To compare the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and the modified van Herick grading system in the assessment of angle closure, using gonioscopy as the reference standard. DESIGN: Prospective comparative study. PARTICIPANTS: One hundred twenty phakic subjects (53 with primary angle closure and 67 with open angles) with no history of laser or intraocular surgery. METHODS: The modified van Herick grading system was used to grade the peripheral anterior chamber depth (ACD) clinically. The SPAC was used to assess ACD, and this was graded categorically as S (suspect angle closure), P (potential angle closure), or N (normal) and numerically from 1 to 12. One randomly selected eye of each subject underwent examination with the modified van Herick grading, SPAC, Goldmann applanation tonometry, optic disc examination, and gonioscopy. The SPAC measurements, modified van Herick grades (0%, 5%, 15%, 25%, 40%, 75%, and > or =100% of corneal thickness), and gonioscopy (graded as narrow or open) were correlated using the Spearman correlation coefficient. The receiver operating characteristics of the 2 methods to detect angle closure also were compared. MAIN OUTCOME MEASURES: Grading of ACD by the SPAC, the modified van Herick system, and gonioscopic grading of the angle. RESULTS: The SPAC results correlated well with the modified van Herick grading system (categorical grade, r = 0.527; numerical grade, r = 0.542; P<0.0001). For eyes graded as having narrow angles by gonioscopy, the area under the curve (AUC) for SPAC categorical grade S or P was 0.790; sensitivity and specificity were 84.9% and 73.1%, respectively. For the modified van Herick grading system, using a cutoff of peripheral ACD < or = 25% corneal thickness, the AUC was 0.872 and sensitivity and specificity were 84.9% and 89.6%. Compared with gonioscopy that found 53 of 120 cases of narrow angles, the SPAC graded more eyes as having narrow angles (63/120) than the modified van Herick system (52/120). CONCLUSIONS: The SPAC correlated well with the modified van Herick system in grading peripheral ACD. However, the SPAC appeared to overestimate the proportion of eyes with narrow angles relative to gonioscopy and the modified van Herick grading system.

Adult↗

PubMed2006

Detection of primary angle closure using anterior segment optical coherence tomography in Asian eyes.

OBJECTIVE: To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle closure when compared with gonioscopy in Asian subjects. DESIGN: Prospective observational case series. PARTICIPANTS: Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery. METHODS: Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions. MAIN OUTCOME MEASURES: Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard. RESULTS: Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 [66.7%] eyes) and by gonioscopy in 99 (49.5%) patients (152 [44.4%] eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval [CI], 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard, specificity of AS-OCT in the dark was 55.4% (95% CI, 45.2-65.2) for detecting individuals with angle closure. CONCLUSION: Anterior segment OCT is a rapid noncontact method of imaging angle structures. It is highly sensitive in detecting angle closure when compared with gonioscopy. More persons are found to have closed angles with AS-OCT than with gonioscopy.

Adult↗

PubMed2006

Imaging of trabeculectomy blebs using anterior segment optical coherence tomography.

OBJECTIVE: To image trabeculectomy blebs using anterior segment optical coherence tomography (AS-OCT). DESIGN: Prospective cross-sectional study. PARTICIPANTS: Fifty-five patients who had previously undergone trabeculectomy surgery. METHODS: All blebs were imaged with a prototype of the AS-OCT. Standardized color monophotographs of blebs were also obtained. Blebs were assessed for the following qualitative features: bleb height, thickness of the conjunctiva in the bleb wall, presence of cystic spaces within the bleb wall, apposition of the scleral flap to underlying sclera, and patency of the internal ostium. MAIN OUTCOME MEASURES: For blebs with preoperative intraocular pressure (IOP) > 18 mmHg with or without ocular hypotensive medication, success was defined as last recorded IOP< or =18 mmHg without topical glaucoma medication. For blebs with preoperative IOP< or =18 mmHg with ocular hypotensive medication, success was defined last recorded IOP< or =18 mmHg with cessation of ocular hypotensive medication. For blebs with preoperative IOP< or =18 mmHg without ocular hypotensive medication, a 20% drop in IOP with no ocular hypotensive medication was accepted as success. RESULTS: Seventy-eight blebs in eyes of 55 patients were imaged. There were 32 (58.2%) men and the mean age was 68.9+/-11.5 years. Fifty-seven (73.1%) blebs were classified as successful. Anterior segment optical coherence tomography identified the following bleb characteristics: total bleb height, bleb cavity, bleb wall thickness, tangential and radial dimensions, scleral flap thickness, and patency of the internal ostium. The majority of successful blebs displayed thickening of the bleb wall. Failed blebs were mostly low and were characterized by ostial occlusion, apposition of conjunctiva-episclera to sclera or apposition of the scleral flap to its bed. Thickening of the bleb wall was typically absent. CONCLUSIONS: AS-OCT is a promising tool to image trabeculectomy blebs. It was able to demonstrate features of bleb morphology not visible with the slit lamp.

Aged↗

PubMed2006

An outbreak of Fusarium keratitis associated with contact lens wear in Singapore.

CONTEXT: Fungal keratitis is a potentially blinding condition that is rarely seen with contact lens wear. OBJECTIVE: To describe a nationwide outbreak of fungal keratitis caused by Fusarium species among contact lens wearers in Singapore. DESIGN, SETTING, AND PATIENTS: Nationwide, hospital-based case series. All cases of fungal keratitis among contact lens wearers in all ophthalmology departments in Singapore were reviewed along with the charts of all contact lens wearers with culture-proven fungal keratitis from March 2005 through May 2006. A standardized telephone interview was conducted to obtain additional clinical information. MAIN OUTCOME MEASURE: Diagnosis of Fusarium keratitis associated with contact lens wear. RESULTS: During the study period, 66 patients (68 affected eyes) were diagnosed with Fusarium keratitis associated with contact lens wear; the estimated annual national incidence is 2.35 cases per 10,000 contact lens wearers (95% confidence interval, 0.62-7.22). Patients ranged in age from 13 to 44 years (mean [SD], 27.1 [8.4] years), of which 32 (48.5%) were men. The vast majority (65 patients; 98.5%) wore soft, disposable contact lenses; 62 patients (93.9%) reported using 1 brand of contact lens cleaning solution (ReNu, Bausch & Lomb, Rochester, NY), including 42 patients (63.6%) who recalled using ReNu with MoistureLoc. Most patients (81.8%) reported poor contact lens hygiene practices, including overnight use of daily wear contact lenses (19.7%), and use of contact lenses past the replacement date (43.9%). The final best-corrected visual acuity ranged from 20/20 to 20/80. Five patients (5 eyes; 7.4%) required emergency therapeutic or tectonic corneal transplantation. CONCLUSIONS: A new and evolving epidemic of Fusarium keratitis associated with contact lens wear was found in Singapore. Physicians and eye care practitioners worldwide need to be aware of the likelihood of similar outbreaks emerging among contact lens wearers.

Adolescent↗

PubMed2006

Mutations in sodium-borate cotransporter SLC4A11 cause recessive congenital hereditary endothelial dystrophy (CHED2).

Congenital hereditary endothelial dystrophy (CHED) is a heritable, bilateral corneal dystrophy characterized by corneal opacification and nystagmus. We describe seven different mutations in the SLC4A11 gene in ten families with autosomal recessive CHED. Mutations in SLC4A11, which encodes a membrane-bound sodium-borate cotransporter, cause loss of function of the protein either by blocking its membrane targeting or nonsense-mediated decay.

Amino Acid Substitution↗

PubMed2006

Detection of narrow angles and established angle closure in Chinese residents of Singapore: potential screening tests.

PURPOSE: To assess the performance of peripheral and central anterior chamber depth (ACD) measurements, and autorefraction, in identifying Chinese people with occludable drainage angles or established primary angle closure. DESIGN: Population-based cross-sectional analysis. METHODS: Subjects aged 40 years and older were drawn from a representative sample of Chinese Singaporean residents. Limbal chamber depth (LCD) was estimated and central ACD was measured using optical pachymetry and ultrasound. An autorefraction was taken for all subjects. Angle width and the presence of peripheral anterior synechiae were determined by gonioscopy. Receiver operating characteristic curves were generated to show the performance of these tests in detecting occludable angles. RESULTS: A total of 1090 subjects were examined. The prevalence of occludable angles was 6.5%. LCD measurement performed best in detecting occludable angles (area under the curve [AUC] 0.904, 95% confidence interval [CI] 0.870, 0.937). Optical pachymetry and ultrasound measurement of ACD performed less well (AUC 0.859 and 0.810, respectively), and autorefraction performed poorly in detecting occludable angles (AUC 0.632). LCD also gave the best performance in detecting primary angle closure (AUC 0.782, 95% CI 0.727, 0.837). CONCLUSIONS: Limbal LCD estimation outperforms other methods of measuring ACD as a screening tool for the detection of occludable drainage angles in the Chinese population of Singapore.

Adult↗

PubMed2006

Effect of trabeculectomy on lens opacities in an East Asian population.

OBJECTIVE: To examine the progression of lens opacity in Asian people after trabeculectomy and determine associated risk factors. METHODS: This was an observational case series of 243 people aged 36 to 82 years. Trabeculectomy was performed on 1 eye of each subject. Lens opacity was measured yearly using the Lens Opacification Classification System III. The main outcome measure was worsening of lens opacity defined as an increase of 2 or more Lens Opacification Classification System III units in any of the 3 lens regions, nuclear, cortical, and posterior subcapsular. Risk of progression was evaluated using logistic regression models. RESULTS: Data for 177 people were analyzed. One hundred seventeen (66%) of 177 subjects showed progression in opacity in any lens region at 3 years. Seventy-seven (66%) of 117 of those who progressed did so during the first year. Of these, 63 (82%) of 77 had lens opacity in the posterior subcapsular region. Factors associated with progression of posterior-subcapsular lens opacity at 1 year were diabetes (odds ratio, 2.4; 95% confidence interval, 1.0-5.4), use of antiglaucoma medication, dosage of topical steroid postoperatively, and being operated on by a trainee surgeon (odds ratio, 2.3; 95% confidence interval, 1.0-5.2). CONCLUSIONS: Trabeculectomy is associated with progression of lens opacity predominantly in the posterior subcapsular region. Modification of risk factors such as postoperative steroid use may delay progression.

Adult↗

PubMed2006

Inferior corneal decompensation following laser peripheral iridotomy in the superior iris.

PURPOSE: To describe a previously unreported clinical entity of inferior corneal decompensation occurring as a long-term complication of superior laser peripheral iridotomy. DESIGN: Retrospective, non-comparative observational case series. METHODS: Chart review of 14 subjects (16 eyes) with inferior corneal decompensation. RESULTS: All patients were Chinese, most were females (71.4%), and the mean age was 69.5 +/- 8.1 year. The mean interval from iridotomy to the onset of inferior corneal decompensation was 66.1 +/- 34.0 months. The most common indication for laser iridotomy was for prophylaxis, either in the fellow eye of acute angle closure (43.8%) or for occludable angles (12.5%). CONCLUSIONS: Corneal decompensation in the inferior part of the cornea at a site remote from the iridotomy is a rare but important complication of laser iridotomy. Because many of the laser iridotomies were performed prophylactically in eyes without glaucoma, patients may need to be warned of this risk.

Aged↗

PubMed2006

Peripapillary retinal nerve fiber layer thickness variations with myopia.

PURPOSE: To determine the relationship between peripapillary retinal nerve fiber layer (RNFL) thickness and myopia using optical coherence tomography (OCT). DESIGN: Prospective observational case series. METHODS: One hundred thirty-two young males with myopia (spherical equivalent [SE], -0.50 to -14.25 diopters) underwent ophthalmic examination of one randomly selected eye. Optical coherence tomography (OCT-1, version 4.1) was performed by a single operator using circular scans concentric with the optic disc with scan diameters of 3.40 mm, 4.50 mm, and 1.75 x vertical disc diameter (VDD). For each scan diameter, mean peripapillary RNFL thickness was calculated. Statistical analysis comprised repeated-measurements analysis and Pearson correlation. RESULTS: Mean peripapillary RNFL thickness did not correlate with SE for the 3.40-mm (r = -0.11, P = 0.22), 4.50-mm (r = -0.103, P = 0.24), or 1.75xVDD (r = -0.08, P = 0.36) OCT scan diameters. Neither did mean peripapillary RNFL thickness correlate with axial length for the 3.40-mm (r = -0.04, P = 0.62), 4.50-mm (r = 0.03, P=0.75), or 1.75xVDD (r = -0.02, P = 0.78) scan diameters. Mean peripapillary RNFL thicknesses for the 3.40-mm, 4.50-mm, and 1.75xVDD scans were 101.1+/-8.2 microm (95% confidence interval [CI], 99.4-102.8), 78.9+/-8.2 microm (95% CI, 77.5-80.3), and 97.5+/-10.9 microm (95% CI, 95.6-99.4), respectively. CONCLUSIONS: Mean peripapillary RNFL thickness did not vary with myopic SE or axial length for any OCT scan diameter investigated. Retinal NFL thickness measurements may be a useful parameter to assess and monitor glaucoma damage in myopic subjects.

Adult↗

PubMed2006

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.

Acute Disease↗

PubMed2006

Long-term outcomes in fellow eyes after acute primary angle closure in the contralateral eye.

PURPOSE: To determine the long-term outcome of the contralateral eye in Asian persons with a unilateral attack of acute primary angle closure (APAC). DESIGN: Cross-sectional observational case series. PARTICIPANTS: Seventy-nine individuals who were examined from 4 to 10 years after a unilateral episode of APAC at 2 Singapore hospitals. METHODS: All subjects underwent a complete eye examination. The optic discs were graded clinically and photographically for the presence of glaucomatous optic neuropathy, and automated visual field tests were assessed for damage. All visual fields and optic nerve photographs (when available) underwent a second evaluation by a masked glaucoma specialist, who assessed whether the changes were compatible with glaucoma. MAIN OUTCOME MEASURES: Glaucomatous optic neuropathy, intraocular pressure (IOP), and visual impairment (defined as best-corrected visual acuity of worse than 6/12). RESULTS: Ninety of 138 eligible patients (65.2%) with APAC were examined, 79 with unilateral attacks. Subjects were predominantly Chinese (n = 68; 86%). There were 54 females (68%), and mean age was 68.5+/-8.9 years (standard deviation) at the time of APAC, with a mean duration of 6.3+/-1.5 years from the time of the APAC episode to the study examination. The contralateral eyes of 7 patients (8.9%) had definite or probable glaucoma, 2 of whom were felt to have glaucoma in that eye at the time of the attack. Three eyes had markedly cupped optic discs (cup-to-disc ratio > or = 0.9). Thirteen eyes (16.9%) had best-corrected vision worse than 6/12, due to cataract in almost half the cases. Only 1 eye had vision < 6/60, the cause of which was corneal decompensation. One other patient had only a central island remaining with vision of 6/12. Mean IOP of the study participants was 15.7+/-4.7 mmHg, with 6 subjects (7.6%) having undergone trabeculectomy. CONCLUSIONS: Definite or probable glaucoma was present at the time of diagnosis in 2 (2.5%) fellow eyes and developed in an additional 5 (6.5%) with a mean follow-up of 6 years. More than 80% of this cohort retained good vision in the contralateral eye, in contrast to the eye that underwent APAC. Unoperated cataract accounted for most of the visual impairment in this group.

Acute Disease↗

PubMed2006

Lens opacity, thickness, and position in subjects with acute primary angle closure.

PURPOSE: To compare lens thickness (LT), lens position (LP), relative lens position (RLP), and degree and type of lens opacity between affected and fellow eyes of subjects with acute primary angle closure (APAC) to identify any differences in lens characteristics that may be contributory to the acute episode. In addition, axial length (AL) and anterior chamber depth (ACD) measurements were evaluated. METHODS: Seventy-three study subjects with unilateral APAC were treated with sequential laser iridotomy (LI) in both eyes. Two weeks after LI, ACD, LT, and AL measurements were made in both eyes using ultrasound pachymetry. LP was defined as ACD+1/2LT and RLP as LP/AL. The Lens Opacity Classification III (LOCS III) System was used for grading lens opacity. RESULTS: The subjects were 90% Chinese and 63% female. Mean age was 61.0+/-10.9 years. Significant differences between the affected and fellow eyes were found in the ACD (2.11+/-0.35 vs 2.18+/-0.23; P=0.02) and LP (4.61+/-0.47 vs 4.75+/-0.29; P=0.02). Cortical opacity was greater in fellow eyes (0.32+/-0.72 vs 0.53+/-0.95; P=0.02). There was no difference in LT, RLP, or degree of lens opacity in the nuclear and posterior subcapsular regions. CONCLUSIONS: Compared with fellow eyes, APAC-affected eyes have shallower ACD, more anterior LP, and less cortical opacity. These differences may be contributory to APAC.

Acute Disease↗

PubMed2006

Myopia, axial length, and OCT characteristics of the macula in Singaporean children.

PURPOSE: The purpose of this study was to evaluate the associations between macular volume and thickness, as assessed by optic coherence tomography (OCT), with refraction and axial length (AL) in children. METHODS: A total of 104 Chinese school children (51 girls and 53 boys) 11 to 12 years of age were randomly selected from one school during the 2005 examination in the Singapore Cohort Study of the Risk Factors for Myopia (SCORM). Cycloplegic autorefraction was performed to obtain refraction (defined as spherical equivalent [SE]) and ultrasound biometry performed to obtain the AL. Macular volume and thickness were then measured (StratusOCT3; Carl Zeiss Meditec, Dublin, CA). RESULTS: Children with moderate myopia (SE at least -3.0 D) tended to have smaller total macular volume and thinner quadrant-specific macular thickness (except in the inferior and superior inner quadrants), followed by children with low myopia (-0.5 -0.5 D). Total macular volume was positively associated with SE (beta=1.58, 95% CI, 0.84 to 2.32, standardized beta=0.14, P<0.001) and negatively associated with AL (beta=-1.20, 95% CI, -1.62 to -0.79, standardized beta=0.45, P<0.001) in multiple linear regression models controlling for age and gender. CONCLUSIONS: In children, increasing axial myopia was associated with reduced macular volume and thickness. These findings suggest that early anatomic changes may be present in the retinas of children with axial myopia.

Anthropometry↗

PubMed2005

Anterior chamber depth and the risk of primary angle closure in 2 East Asian populations.

OBJECTIVE: To evaluate the risk of peripheral anterior synechiae (PAS) and glaucomatous optic neuropathy attributable to primary angle closure at varying anterior chamber depths (ACDs) in two East Asian populations. METHODS: Participants 40 years and older were from 2 population-based glaucoma surveys in Mongolia and Singapore. Central ACD was measured by optical pachymetry. Presence of PAS was determined by dynamic gonioscopy. Cases with secondary PAS were excluded. Glaucomatous optic neuropathy was diagnosed in subjects with structural and functional evidence of glaucoma. RESULTS: A total of 2032 subjects, consisting of 942 Mongolians and 1090 Chinese Singaporeans, were included in this study. A logistic model of the relationship between ACD and PAS among Singaporeans showed a consistent, incremental increase in PAS across the entire range of ACD. In deeper anterior chambers the rate of PAS exceeded that seen in Mongolians. In Mongolians, there was a clear threshold for ACD (2.4 mm) at or above which PAS were very uncommon. With ACD less than 2.4 mm, the rate of PAS rose rapidly to overtake that seen in Singaporeans. CONCLUSIONS: Shallow anterior chambers are a significant risk factor for angle closure in East Asians, although the nature of the association is specific to the individual population. There was a trend toward higher rates of glaucomatous optic neuropathy in people with the shallowest anterior chambers.

Adult↗

PubMed2005

Optic disk ovality as an index of tilt and its relationship to myopia and perimetry.

PURPOSE: To examine the association of optic disk ovality with myopic refractive error, axial length, and the visual field. DESIGN: Prospective observational case series. METHODS: The study included 150 randomly recruited male subjects with myopia. In all cases, one eye was randomly selected, and subjective refraction, slit-lamp examination, applanation tonometry, gonioscopy, A-scan ultrasonography, funduscopy, and color optic disk stereo photography were performed. Disk ovality was assessed using the ratio of minimum to maximum disk diameter (index of tilt). A ratio of < or = 0.8 was considered as significant disk tilt. Visual fields were tested using static automated threshold perimetry with two methods of optical correction: trial lenses and contact lenses. RESULTS: Of the total sample, 137 subjects completed the study. Mean age was 21.2 +/- 1.1 year, and mean spherical equivalent was -6.36 +/- 3.56 diopters. Mean ovality ratio was 0.83 +/- 0.09; 55 subjects (40.2%) had significant tilted optic disks. Greater optic disk ovality (tilt) correlated with greater myopia (P = .009) and longer axial length (P = .009); 95.6% of subjects had normal visual fields with both methods of optical correction. Using multiple linear regression analysis, greater tilt was independently related to a higher mean defect on testing with trial lenses (P < .01). CONCLUSIONS: Increased optic disk tilt was associated with higher myopia and reduced sensitivity on field testing. These factors are important in the assessment of glaucoma in patients with myopia.

Adult↗

PubMed2005

Use of surodex in phacotrabeculectomy surgery.

PURPOSE: To evaluate the use of Surodex (Oculex Pharmaceuticals, Sunnyvale, California) a drug delivery system incorporating 60 micrograms of dexamethasone in a pellet, in phacotrabeculectomy surgery. DESIGN: Nonrandomized, prospective, interventional case series. METHODS: Phacotrabeculectomy was performed on 37 Asian subjects with primary open-angle glaucoma (POAG) using a standardized technique. All subjects received a Surodex pellet underneath the scleral flap. Results were compared with those of 31 POAG subjects who had undergone phacotrabeculectomy augmented with 50 mg/ml of intraoperative 5-fluorouracil (5-FU) during the same period. RESULTS: Mean follow-up in months was 19.7 +/- 7.9 and 22.1 +/- 6.2 for the Surodex and 5-FU groups, respectively (P = .29). There was a 20.1% decrease in intraocular pressure in the Surodex group compared with 28.5% decrease in the 5-FU group (P = .6). Postoperative complications occurred in three cases (8.1%) and six cases (19.3%), respectively (P = .04). CONCLUSIONS: Combined phacotrabeculectomy surgery augmented by intra-scleral placement of Surodex results in good control of IOP and a low incidence of complications.

Anterior Eye Segment↗

PubMed2005

Configuration of the drainage angle, intraocular pressure, and optic disc cupping in subjects with chronic angle-closure glaucoma.

OBJECTIVE: To investigate the relationship between drainage angle configuration with untreated intraocular pressure (IOP) and optic disc cupping in subjects with chronic angle-closure glaucoma (CACG). DESIGN: Prospective, observational study. PARTICIPANTS: Two hundred seventy-five Asian subjects with CACG who participated in a randomized controlled trial that investigated the IOP-reducing effect of latanoprost and timolol. METHODS: Chronic angle-closure glaucoma was defined as the presence of glaucomatous optic neuropathy (with or without a visual field defect), an anterior chamber angle in which the pigmented trabecular meshwork was not visible for at least 180 degrees on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in association with elevated IOP of 21 mmHg or more. Static and dynamic gonioscopy were performed, the angles were graded in each quadrant according to the Shaffer scheme, and the number of clock hours of PAS was recorded. The untreated IOP and vertical cup-to-disc ratio were correlated with mean angle width and extent of PAS. MAIN OUTCOME MEASURES: Mean angle width, clock hours of PAS, IOP, and vertical cup-to-disc ratio. RESULTS: Most subjects were female (75%), and the mean age was 62.9+/-9.4 years. The mean angle width was 0.77+/-0.53 and the mean number of clock hours of PAS was 4.77+/-3.2 hours. Untreated IOP correlated with angle width (r = -0.23; P<0.001) and clock hours of PAS (r = 0.22; P<0.001). Vertical cup-to-disc ratio also correlated with angle width (r = -0.17; P = 0.004) and PAS (r = 0.28; P<0.001). Performing a multiple linear regression using baseline IOP as the outcome variable with age, gender, clock hours of PAS, and angle width as predictors, there was a 0.39-mmHg (95% confidence interval, 0.15-0.63) increase in baseline untreated IOP for each unit increase in clock hours of PAS (P = 0.002). CONCLUSIONS: In subjects with CACG, the extent of PAS and a narrower width of the drainage angle were associated with higher untreated IOP and a larger vertical cup-to-disc ratio.

Adult↗

PubMed2005

Degree of angle closure and the intraocular pressure-lowering effect of latanoprost in subjects with chronic angle-closure glaucoma.

OBJECTIVE: To examine the relationship between the configuration of the drainage angle and intraocular pressure (IOP)-lowering efficacy of latanoprost in subjects with chronic angle-closure glaucoma (CACG). DESIGN: Prospective observational case series. PARTICIPANTS: One hundred thirty-seven Asian subjects with CACG. METHODS: Study subjects had participated in a 12-week, randomized, double-masked study that assessed the IOP-reducing effect of latanoprost. Chronic angle-closure glaucoma was defined as optic neuropathy with or without a visual field defect, an anterior chamber angle in which the trabecular meshwork was not visible for at least 180 degrees on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in association with a chronically elevated IOP. Static and dynamic gonioscopy was performed at baseline. The angles were graded in each quadrant according to the Shaffer scheme, and the number of clock hours of PAS was recorded. The change in daily IOP (defined as the mean of the 9:00 am and 5:00 pm IOP time point values) from baseline to week 12 was analyzed and correlated with mean angle width and extent of PAS. RESULTS: One hundred thirty-seven Asian subjects with CACG completed the study in the latanoprost-treated group. Most subjects were female (75%), and the mean age was 62.6+/-9.4 years. At baseline, the mean angle width was 0.84+/-0.55, and the mean number of clock hours of PAS was 4.67+/-2.95. After 12 weeks of treatment, latanoprost reduced IOP from 25.0+/-5.5 mmHg to 17.5+/-5.0 mmHg (P<0.001). The percent change in IOP produced by latanoprost was not associated with mean angle width (Spearman's r = 0.04, P = 0.64) or the number of clock hours of PAS (Spearman's r = -0.15, P = 0.08). CONCLUSIONS: In subjects with CACG, the IOP-reducing efficacy of latanoprost was not affected by the degree of angle narrowing or extent of synechial angle closure.

Adult↗