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ABSTRACT: OBJECTIVE: To investigate the use of swept-source optical coherence tomography (OCT) for measuring the area and degree of peripheral anterior synechia (PAS) involvement in patients with angle-closure glaucoma. DESIGN: Cross-sectional study. PARTICIPANTS: Twenty-three eyes with PAS (detected by indentation gonioscopy) from 20 patients with angle-closure glaucoma (20 eyes had primary angle-closure glaucoma and 3 eyes had angle-closure glaucoma secondary to chronic anterior uveitis [n = 2] and Axenfeld-Rieger syndrome [n = 1]). METHODS: The anterior chamber angles were evaluated with indentation gonioscopy and imaged by swept-source OCT (Casia OCT, Tomey, Nagoya, Japan) in room light and in the dark using the "angle analysis" protocol, which was composed of 128 radial B-scans each with 512 A-scans (16-mm scan length). The area and degree of PAS involvement were measured in each eye after manual detection of the scleral spur and the anterior irido-angle adhesion by 2 masked observers. The interobserver variability of the PAS measurements was calculated. MAIN OUTCOME MEASURES: The agreement of PAS assessment by gonioscopy and OCT, the area and the degree of PAS involvement, and the intraclass correlation coefficient (ICC) of interobserver PAS measurements. RESULTS: The area of PAS (mean ± standard deviation) was 20.8±16.9 mm(2) (range, 3.9-74.9 mm(2)), and the degree of PAS involvement was 186.5±79.9 degrees (range, 42-314 degrees). There was no difference in the area of PAS (P = 0.90) and the degree of PAS involvement (P = 0.95) between images obtained in room light and in the dark. The interobserver ICCs were 0.99 (95% confidence interval [CI], 0.98-1.00) for the area of PAS and 0.99 (95% CI, 0.97-1.00) for the degree of PAS involvement. There was good agreement of PAS assessment between gonioscopy and OCT images (kappa = 0.79; 95% CI, 0.67-0.91). CONCLUSIONS: Swept-source OCT allows visualization and reproducible measurements of the area and degree of PAS involvement, providing a new paradigm for evaluation of PAS progression and risk assessment for development of angle-closure glaucoma. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmology 03/2013; · 5.45 Impact Factor
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ABSTRACT: OBJECTIVE:: To determine the visibility of the scleral spur (SS), Schwalbe's line (SL), and Schlemm's canal (SC) imaged by a swept-source optical coherence tomographer (OCT). METHODS:: One eye from each individual was randomly selected from 30 normal subjects and 30 patients with primary open-angle glaucoma for anterior segment imaging with a swept-source OCT. The angles were imaged with 2 protocols: (1) high-density (HD, a raster of 64 B-scans each with 512 A-scans over 8 mm) and (2) low-density scans (LD, 128 radial scans each with 512 A-scans over 16 mm). The visibility of the angle structures was determined by 2 masked observers and compared among the superior (90 degrees), nasal (0 degrees), inferior (270 degrees), and temporal (180 degrees) quadrants. RESULTS:: The interobserver agreement for assessment of visibility of the angle structures was high with agreement coefficients ranging between 0.769 and 0.987. The SS, SL, and SC were visible by both observers in 95% to 100%, 68% to 98%, and 12% to 42% of a total of 240 (4×60) quadrants in 60 HD images, respectively. The visibility was reduced in LD images (50% to 95%, 0% to 10%, and 0%, respectively). The temporal and nasal quadrants generally had superior visibility of the angle structures than the superior and inferior quadrants. CONCLUSIONS:: The SS, SL, and SC could be identified with the swept-source OCT although their visibility varied with the scan location and scan density. The SS was best visualized, followed by the SL and then the SC in the OCT images.
Journal of glaucoma 01/2013; · 1.74 Impact Factor
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ABSTRACT: OBJECTIVE: To compare phacoemulsification versus trabeculectomy with adjunctive mitomycin C in medically uncontrolled chronic angle-closure glaucoma (CACG) without cataract. DESIGN: Prospective, randomized clinical trial. PARTICIPANTS: Fifty medically uncontrolled CACG eyes without cataract of 50 patients. INTERVENTION: Patients were randomized into undergoing either phacoemulsification or trabeculectomy with adjunctive mitomycin C. After surgery, patients were followed up every 3 months for 2 years. MAIN OUTCOME MEASURES: Intraocular pressure (IOP) and requirement for glaucoma drugs. RESULTS: Twenty-six CACG eyes were randomized to receive phacoemulsification, and 24 eyes underwent trabeculectomy with mitomycin C. Phacoemulsification and trabeculectomy resulted in significant and comparable IOP reduction at 24 months after surgery (reduction of 8.4 mmHg or 34% for phacoemulsification vs. 8.9 mmHg or 36% for trabeculectomy; P = 0.76). Over first 24 months, trabeculectomy-treated eyes required on average 1.1 fewer drugs than phacoemulsification-treated eyes (P<0.001). However, trabeculectomy was associated with significantly more surgical complications than phacoemulsification (46% vs. 4%; P = 0.001). Eight (33%) of 24 trabeculectomy eyes demonstrated cataract during follow-up. CONCLUSIONS: Both phacoemulsification and trabeculectomy are effective in reducing IOP in medically uncontrolled CACG eyes without cataract. Trabeculectomy is more effective than phacoemulsification in reducing dependence on glaucoma drugs, but is associated with more complications. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmology 09/2012; · 5.45 Impact Factor
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American journal of ophthalmology 08/2012; 154(2):418. · 3.83 Impact Factor
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ABSTRACT: differentiate the associations of exudative age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) with the ARMS2/HTRA1 locus.
The entire ARMS2 sequence was sequenced and HTRA1 rs11200638 genotyped in 568 unrelated Chinese individuals: 156 exudative AMD patients, 164 PCV patients, and 248 controls. A meta-analysis was performed to examine the effects of rs10490924 and rs11200638 at the ARMS2/HTRA1 locus in PCV.
In total, 31 polymorphisms in ARMS2 were identified. Significant associations with both exudative AMD and PCV were observed in 11 of them and HTRA1 rs11200638, with different genotypic distributions between exudative AMD and PCV (P < 0.001). After adjusting for rs11200638, ARMS2 rs10490924 remained significantly associated with exudative AMD (P = 0.011), but not with PCV (P = 0.077). Meta-analysis showed consistent allelic associations of rs10490924 and rs11200638 with PCV in different study populations.
There is a strong and consistent association of the ARMS2/HTRA1 locus with both exudative AMD and PCV, suggesting the two disorders share, at least partially, similar molecular mechanisms. Different effect sizes indicate the existence of additional genetic and environmental factors affecting them to different extents.
Investigative ophthalmology & visual science 04/2012; 53(6):3175-82. · 3.43 Impact Factor
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Ophthalmology 04/2012; 119(4):886-7. · 5.45 Impact Factor
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ABSTRACT: To study the efficacy and safety of triple therapy (sub-Tenon triamcinolone [∼70 mg], intravitreal bevacizumab [1.25 mg], and focal/grid laser) for refractory diabetic macular edema.
Twenty-nine eyes of 29 patients who received triple therapy were monitored for central foveal thickness, best-corrected visual acuity (BCVA), and side effects over a 1-year period. Their results were compared with a focal/grid laser historical control group of 18 eyes (18 patients).
In the triple therapy group, mean central foveal thickness significantly reduced from baseline value of 441 μm to 298 μm at Month 12 (P < 0.001), but there was no significant change of BCVA. In the control group, there were no sustained significant changes of central foveal thickness or BCVA. A subgroup analysis of 7 eyes in the triple therapy group with baseline BCVA of ≤20/100 showed significant BCVA improvements from 4 weeks to 9 months. The maximum improvement was achieved at 6 months, when the mean BCVA improved by 9.5 Early Treatment Diabetic Retinopathy Study letters from baseline. Intraocular pressure rise (31.0%), partial ptosis (17.2%), and significant cataractogenesis (8.7%) were encountered in the triple therapy group but not in the control group.
Sustained reduction of central foveal thickness was achieved with triple therapy over the 1-year study period. Significant visual improvement was seen only in patients with worse baseline BCVA, but not in the triple therapy group as a whole. Significant side effects of intraocular pressure rise, ptosis, and cataractogenesis were encountered in the triple therapy group.
Retina (Philadelphia, Pa.) 02/2012; 32(4):672-8. · 2.93 Impact Factor
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ABSTRACT: Purpose: To provide a systematic review of the published studies pertaining to the lifestyle modification, dietary, nutritional and vitamins supplements for preventing occurrence or halting deterioration of age-related macular degeneration (AMD). Methods: The literature searches from 1990 to December 2010 with following keywords, 'age related macular degeneration', 'nutrition', 'antioxidant', 'diet' and 'vitamins supplements' using search engines Pubmed, Google Scholar, Medline and the Cochrane Library. Meta-analyses, population-based cohort studies and case-controlled trials were reviewed, whereas small cases series, case reports, commentaries, abstracts in proceedings or personal observations were excluded. Results: Smoking and obesity are identified risk factors for AMD. High dietary intakes of omega-3 fatty acids, and macular xanthophylls lutein and zeaxanthin have been associated with a lower risk of prevalence and incidence in AMD. Vitamin B and extracts from wolfberry, Gingko biloba and berry anthocyanins were also subjects of intense research interests, but there has been no concluding scientific evidence yet. The Age-Related Eye Disease study (AREDS) is the only large-scale randomized controlled clinical trial to show beneficial effect of AREDS formulation of vitamins C, E, beta-carotene and zinc with copper in reducing the risk progression to advanced AMD in patients with intermediate AMD or with advanced AMD in one eye. Conclusion: Quit smoking is an important advice to patients to prevent or slow the progress of AMD. There is no recommendation for routine nutritional or vitamins supplementation for primary prevention. However, patients with documented intermediate risk of AMD or advanced AMD in one eye are recommended to take AREDS-type vitamin supplements.
Acta ophthalmologica 01/2012; · 2.44 Impact Factor
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ABSTRACT: To investigate age-related changes of the retinal nerve fiber layer (RNFL) imaged by a spectral-domain optical coherence tomography (OCT).
Prospective, cross-sectional, and longitudinal studies.
One hundred normal individuals were recruited for cross-sectional analysis, 35 of whom were randomly selected for longitudinal analysis.
The circumpapillary average and quadrant RNFL thicknesses were measured by the Cirrus HD-OCT. In the longitudinal study, participants were followed at 4-month intervals for a mean of 30 months (range, 24-41 months) for RNFL and visual field measurements. Cross-sectional RNFL data were analyzed with multiple linear regression models with adjustment of spherical error, optic disc area, and signal strength. Longitudinal RNFL measurements were analyzed with linear mixed models with fixed coefficients on follow-up duration, baseline RNFL thickness, spherical error, optic disc area, and signal strength. Factors influencing the rate of change of RNFL measurements were analyzed in the interaction terms with "duration" in the linear mixed models.
Rates of change of average and quadrant RNFL thicknesses.
In the cross-sectional analysis, significant negative correlations were found between age and average (-0.33 μm/year; P = 0.011), inferior (-0.45 μm/year; P = 0.037), and temporal (-0.31 μm/year; P = 0.046) RNFL thicknesses. In the longitudinal analysis, the mean rates of change of average, superior, and inferior RNFL thicknesses were -0.52 (95% confidence interval [CI], -0.86 to -0.17), -1.35 (95% CI, -2.05 to -0.65) and -1.25 μm/year (95% CI, -1.78 to -0.71), respectively, after adjusting for baseline RNFL thickness, spherical error, disc area, and signal strength. There was no detectable RNFL reduction in the nasal and temporal quadrants. The only significant factor influencing the rates of change of RNFL measurements was the baseline RNFL thickness. A greater baseline RNFL thickness was associated with a faster rate of change.
Progressive, age-related decline of RNFL thickness can be detected with longitudinal OCT imaging. Rate estimates derived from trend analysis for detection of glaucomatous RNFL progression should be interpreted with reference to the normal ranges of age-related reduction, particularly when the baseline RNFL measurement is large.
Ophthalmology 01/2012; 119(4):731-7. · 5.45 Impact Factor
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ABSTRACT: Purpose. To evaluate the clinical features, microbiological spectrum, and treatment outcomes of endogenous endophthalmitis. Methods. Retrospective review of consecutive cases with infective endogenous endophthalmitis presenting from 2000 to 2007. The main outcome measure was the visual outcome at the latest follow-up visit. Other outcome measures included microbiological investigations, anatomical and clinical outcomes. Results. 22 eyes of 21 patients were included, and the mean follow-up duration was 2.7 years. Eyes with fungal endogenous endophthalmitis were more likely to have visual acuity of finger counting or better at presentation compared with those with bacterial endogenous endophthalmitis (odds ratio = 15.0, P = 0.013). Gram-negative microorganisms accounted for 50% of infections, while fungal and gram-positive organisms accounted for 27.3% and 22.7%, respectively. Despite treatment, the visual outcome was poor in general as 10 (45.5%) eyes had no light perception at the latest follow-up visit and 6 (27.3%) eyes required enucleation or evisceration. Contrary to previous studies, fungal endogenous endophthalmitis did not appear to have better visual outcome compared with bacterial endogenous endophthalmitis. Conclusion. Gram-negative microorganisms were the main causative pathogens of endogenous endophthalmitis in Hong Kong. The visual prognosis of endogenous endophthalmitis is generally poor as almost 50% of eyes were blind despite treatment.
Journal of Ophthalmology 01/2012; 2012:265078.
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ABSTRACT: To compare pain scores with and without supplementary topical 2% lidocaine gel in patients undergoing simultaneous bilateral laser-assisted in situ keratomileusis (LASIK) under topical anesthesia using 0.5% proparacaine eye drops.
Randomized double-masked placebo-controlled trial.
Fifty-one Chinese subjects (102 eyes, with 51 eyes in each arm) were included. One eye was randomly allocated to have supplementary 2% lidocaine gel while the other eye received carbomer gel as control, in addition to topical 0.5% proparacaine. The pain scores for each eye during microkeratome flap creation, during laser ablation, and at 15, 30, and 45 minutes after LASIK were assessed. An overall pain score of the LASIK procedure was also obtained. Primary outcome measures were pain scores during and after LASIK. Secondary outcomes included need for additional topical anesthesia, patient cooperation score, and duration and complications of surgery.
In the 2% lidocaine gel-treated group, the pain scores were significantly lower during microkeratome flap creation and laser ablation, and postoperatively at 30 and 45 minutes (P<.05 for all). Patients in the lidocaine gel group required less additional topical anesthesia (P=.0004) and were more cooperative (P=.019) as compared to the carbomer gel group. No surgical or postoperative complications were observed.
The use of supplementary 2% lidocaine gel in LASIK is effective in lowering the pain experienced during and up to 45 minutes after LASIK.
American journal of ophthalmology 11/2011; 153(4):627-31, 631.e1-3. · 3.83 Impact Factor
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Acta ophthalmologica 10/2011; 90(5):e413-5. · 2.44 Impact Factor
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Archives of ophthalmology 09/2011; 129(9):1242-3. · 3.86 Impact Factor
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Archives of ophthalmology 09/2011; 129(9):1241-2. · 3.86 Impact Factor
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ABSTRACT: To test an educational intervention promoting the purchase of spectacles among Chinese children.
Randomized, controlled trial.
Children in years 1 and 2 of all 20 junior and senior high schools (ages 12-17 years) in 3 rural townships in Guangdong, China.
Children underwent visual acuity (VA) testing, and parents of participants with presenting VA worse than 6/12 in either eye improving by more than 2 lines with cycloplegic refraction were recommended to purchase glasses. Children at 10 randomly selected schools received a lecture, video, and classroom demonstration promoting spectacle purchase.
Self-reported purchase of spectacles (primary outcome) and observed wear or possession of newly purchased glasses (secondary outcome) at follow-up examinations (mean, 219 ± 87 days after the baseline visit).
Among 15 404 eligible children, examinations were completed for 6379 (74.6%) at intervention schools and 5044 (73.6%) at control schools. Spectacles were recommended for 2236 (35.1%) children at intervention schools and for 2212 (43.9%) at control schools. Of these, 417 (25.7%) intervention schools children and 537 (34.0%, P = 0.45) control schools children reported buying glasses. Predictors of purchase in regression models included female gender (P = 0.02), worse uncorrected VA (P < 0.001), and higher absolute value of refractive error (P = 0.001). Neither the rate of self-reported purchase of glasses or observed wear or possession of newly purchased glasses differed between control schools and intervention schools in mixed-effect logistic regression models. Among children not purchasing glasses, 21.7% had better-eye VA of worse than 6/18.
An intervention based on extensive pilot testing and focus groups in the area failed to promote spectacle purchase or wear. The high burden of remaining uncorrected poor vision underscores the need to develop better interventions.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmology 09/2011; 118(12):2343-50. · 5.45 Impact Factor
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Archives of ophthalmology 08/2011; 129(8):1108. · 3.86 Impact Factor
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ABSTRACT: It has been shown that the pressure-to-cornea index (PCI), which estimates the relative effects of intraocular pressure (IOP) and central corneal thickness (CCT), may differentiate between glaucoma and non-glaucoma states. The authors investigated the utility of the pressure-cornea-vascular index (PCVI) in predicting field-progression in patients with normal tension glaucoma (NTG).
PCVI was constructed from PCI (maximum IOP/CCT(3)) extended with risk factors identified as associated with field-progression in a prospective NTG cohort. Receiver operator characteristics and area under the curve (AUC) of a range of constructs were calculated to arrive at an optimal PCVI.
415 eyes from 415 NTG subjects (184 field-progressed and 231 field-stable) with 3 years of follow-up were analysed. The construct PCVI=(maximum pretreatment office IOP × age at presentation × vertical cup-to-disc ratio at presentation × (1.5 if presence of systemic hypertension; 2.5 if presence of disc haemorrhage; 3.5 if presence of both; 1.0 if none))/(CCT(3)×100) (CCT in mm) gave the highest AUC at 0.71 (95% CI 0.66 to 0.76, p<0.001). The mean PCVI were 113.1±76.8 and 69.7±39.7 for progressed and stable NTG groups, respectively (p<0.001).
PCVI may be useful for predicting progression in NTG with a satisfactory AUC comparable to established scoring systems in neurovascular medicine. Validation of PCVI in other NTG cohorts, preferably of different ethnicity, is necessary. Trial registration number NCT00321386.
The British journal of ophthalmology 08/2011; 95(8):1106-10. · 2.92 Impact Factor
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ABSTRACT: To utilize focus groups (FGs) to identify barriers to cataract surgery specific to older persons in rural Guangdong, China.
Three focus groups in separate locations were carried out for persons aged 60 years and above with best-corrected vision <= 6/18 due to cataract, either accepting or refusing surgery. Participants also ranked responses to questions about acceptance of surgery among the elderly. FG transcripts were coded independently by two investigators using qualitative data management software.
Twenty participants had a mean age of 72.7 ± 6.1 years, 14 (70.0%) were women and 17 (85.0%) were blind (best-corrected vision <= 6/60) in at least one eye. Cost was ranked by two of three groups as the main barrier to surgery, and all groups listed reducing cost as the best strategy to increase surgical uptake. Many respondents planned to use China's New Cooperative Medical Scheme (NCMS) health insurance to pay for surgery. Participants showed poor understanding of cataract, but ranked educational interventions low as methods of increasing uptake. Though opinions of local service quality were poor, respondents did not see quality as an important barrier to accepting service. Participants frequently depended on family members to pay for surgery.
Contrary to some previous reports, cost may be an important barrier to cataract surgery in rural China, which NCMS may help to alleviate. Educational interventions to increase knowledge about cataract are needed, but may face skepticism among patients. Strategies to promote cataract surgery should target the entire family.
Ophthalmic epidemiology 08/2011; 18(4):179-86. · 1.93 Impact Factor
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ABSTRACT: To compare the area and the angular width of localized retinal nerve fiber layer (RNFL) defects imaged by confocal scanning laser ophthalmoscopy (CSLO) and optical coherence tomography (OCT) and to evaluate their agreement.
Cross-sectional study.
Fifty-one eyes of 41 glaucoma patients.
Sixty-one distinctive, localized RNFL defects (17 superior and 44 inferior RNFL defects) detected in RNFL photographs imaged by a CSLO were identified. These patients underwent RNFL imaging with a spectral-domain OCT. The RNFL thickness deviation maps (50×50 pixels) generated by the OCT revealed the locations of abnormal RNFL thicknesses with abnormal pixels denoted in red (RNFL thickness less than the lower 99% normal distribution) or yellow (RNFL thickness less than the lower 95% normal distribution). The RNFL thickness deviation maps were aligned and overlaid with the corresponding CSLO RNFL photographs. The area and the angular width of RNFL defects from the corresponding retinal regions in the CSLO RNFL photographs and the OCT RNFL thickness maps were measured and compared. Their agreement was analyzed with the Bland-Altman plot.
The area and the angular width of RNFL defects and the agreement of RNFL defects measurements between OCT images and CSLO RNFL photographs.
The area and the angular width of RNFL defects measured with the CSLO RNFL photographs were 1.11 ± 0.57 mm² and 23.80 ± 10.38°, respectively, which were significantly smaller than those measured by the OCT RNFL thickness deviation map when abnormal RNFL thickness was defined as less than the lower 95% centile ranges (2.27 ± 0.92 mm² and 74.16 ± 28.74°, respectively; both P < 0.001). When abnormal RNFL thickness was defined as less than the lower 99% centile ranges, a significant difference in angular width (42.11 ± 22.19°; P<0.001), but not in area (1.19 ± 0.68 mm²; P = 0.444) was found between the 2 imaging methods. Bland-Altman plots revealed that a larger RNFL defect was associated with a greater difference in angular width between OCT and CSLO RNFL photography measurements.
The agreement of RNFL defect measurements between CSLO RNFL photography and OCT was poor. The OCT RNFL thickness deviation map could reveal additional RNFL abnormalities not detectable by CSLO RNFL photography.
Proprietary or commercial disclosure may be found after the references.
Ophthalmology 07/2011; 118(11):2196-202. · 5.45 Impact Factor
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Archives of ophthalmology 07/2011; 129(7):963. · 3.86 Impact Factor
