Vijaya Lingam

Determinants of glaucoma awareness and knowledge in urban Chennai.

Aim: To assess the awareness and knowledge levels about glaucoma and its determinants in an urban population of Chennai in south India. Materials and Methods: Chennai glaucoma study (CGS) was a population based prevalence study to estimate the prevalence of glaucoma in a rural and urban south Indian population. A total of 3850 subjects aged 40 years or above participated in the urban arm of CGS. A systematic random sample of 1926 (50.0%) subjects completed a questionnaire that assesses their awareness and knowledge level of glaucoma. Respondents “having heard of glaucoma” even before they were contacted/recruited for the study were defined as “aware” and respondents having some understanding of the eye disease were defined as “knowledgeable”. Results: Overall 13.5% were aware of glaucoma, the age-gender adjusted rate for awareness was 13.3% (95% CI: 11.57 to 15.03). Two clinicians graded knowledge on glaucoma, based on the subjects knowledge of risk factors, definitions and treatment aspects of glaucoma. Overall 8.7% had some knowledge about glaucoma. Among those who had knowledge 0.5% had good knowledge about glaucoma, 4% had fair knowledge and 4.2% had poor knowledge. We observed a very good agreement between the clinicians in grading knowledge (k =0.92). Determinants of glaucoma awareness and knowledge were higher levels of education, females, age, religion and family history of glaucoma. Conclusion: Awareness and knowledge about glaucoma was very low among the urban population of Chennai. We have found that younger subjects and men were less aware of glaucoma. Subjects with lower levels of education were less aware and knew less about glaucoma than their counterparts. The study findings stress the need for health education for effective prevention of blindness due to glaucoma.

A randomized, crossover, open label pilot study to evaluate the efficacy and safety of Xalatan® in comparison with generic Latanoprost (Latoprost) in subjects with primary open angle glaucoma or ocular hypertension

AIM To compare the efficacy and tolerability of Xalatan with generic latanoprost (Latoprost) in subjects with primary open angle glaucoma (POAG) or ocular hypertension (OH). MATERIALS AND METHODS This was a single-center, randomized, open label, crossover, two period comparative study. At the baseline visit, subjects were randomized to two groups. Group A received Xalatan for weeks 1-12 followed by Latoprost for weeks 13-24. Group B received Latoprost for weeks 1-12 followed by Xalatan for weeks 13-24. RESULTS 30 subjects were recruited, 12 in Group A and 18 in Group B. In subjects administered Xalatan, intraocular pressure (IOP) showed a greater decrease (P < 0.001) from 23.64 +/- 3.13 mmHg at baseline to 14.29 +/- 1.61 mmHg at week 12 (fall of 9.35 +/- 3.55 mmHg, 38.66% +/- 10.29) than that seen in the Latoprost group (22.74 +/- 2.47 mmHg to 16.98 +/- 2.49 mmHg, fall of 5.76 +/- 1.41 mmHg; 25.42% +/- 5.98). In period 2 when subjects were crossed over to Xalatan from Latoprost, there was a further fall from 16.98 +/- 2.49 mmHg to 16.09 +/- 1.49 at week 24 (fall of 0.89 +/- 1.59 mmHg; 4.3% +/- 8.76). However, when subjects were crossed over to Latoprost from Xalatan, the IOP rose from 14.29 +/- 1.61 mmHg to 15.36 +/- 1.71 mmHg at week 24 (8.86% +/- 17.76). There was no significant difference in incidence of conjunctival hyperemia or any other adverse events in both the groups. CONCLUSION The magnitude of IOP lowering in patients with POAG and OH with Xalatan and Latoprost is different. In our study, the IOP lowering with Xalatan was higher than that with Latoprost.

Follow-up of primary angle closure suspects after laser peripheral iridotomy using ultrasound biomicroscopy and A-scan biometry for a period of 2 years.

AimTo determine the morphologic changes in the anterior segment of primary angle closure suspects (PACS) who underwent laser peripheral iridotomy (LPI) for a period of 2 years. MethodsPACS (n=82 eyes) of Asian Indian origin who attended the Glaucoma clinic of tertiary eye hospital underwent A-scan biometry and ultrasound biomicroscopy. Anterior chamber depth, anterior chamber angle (ACA), axial length, lens thickness, relative lens position, central corneal thickness, angle opening distance 500, trabecular-ciliary process distance, iris-ciliary process distance, and iris thickness were measured before LPI and after LPI at 1 week, 6 months, 1 year, 1.5 years, and 2 years. Variation in the parameters measured over a period of 2 years was analyzed. ResultsFifteen eyes out of 52 eyes developed into primary angle closure (PAC) with synechial changes. Univariate analysis for the predictive factors of PAC showed no significant association for age, sex, narrow angle, ultrasound biomicroscopy parameters, and vertical cup-disc ratio. When analyzed as continuous variables, decreasing ACA was significant risk factor (95% confidence interval: 0.703, 0.989, P=0.037). Iris-ciliary process distance, ACA, lens thickness, and angle opening distance 500 were the parameters that varied significantly (P<0.05) between “before LPI group” and “after LPI groups.” None of the subjects developed increased intraocular pressure after laser iridotomy. ConclusionsIn this hospital-based study on the course of PACS subjects after LPI, as many as 28% progressed to PAC. Decreasing ACA was the predictive factor for the progression of PACS to PAC. There was no increase in intraocular pressure, history, or symptoms of acute attack of glaucoma among the study subjects after LPI.

Prevalence and associated factors for pterygium and pinguecula in a South Indian population

Citation information: Rashima A, Ramesh S Ve, Lokapavani V, Vijaya L & George R. Prevalence and associated factors for pterygium and pinguecula in a South Indian population. Ophthalmic Physiol Opt 2011. doi: 10.1111/j.1475‐1313.2011.00882.x

Genetic Association of SNPs near ATOH7, CARD10, CDKN2B, CDC7 and SIX1/SIX6 with the Endophenotypes of Primary Open Angle Glaucoma in Indian Population

Primary open angle glaucoma (POAG) belonging to a group of optic neuropathies, result from interaction between genetic and environmental factors. Study of associations with quantitative traits (QTs) is one of the successful strategies to understand the complex genetics of POAG. The current study attempts to explore the association of variations near/in genes like ATOH7, SIX1/SIX6 complex, CDKN2B, CARD10, and CDC7 with POAG and its QTs including vertical cup to disc ratio (VCDR), central corneal thickness (CCT), intra ocular pressure (IOP), and axial length (AL). Case-control study design was carried out in a sample size of 97 POAG cases and 371 controls from South India. Model-based (additive, recessive, dominant) association of the genotypes and their interaction was carried out between cases and controls using chi-square, linear and logistic regression methods. Nominal significance (P<0.05) was observed for QTs like i) VCDR with SNPs rs1900004 (ATOH7); rs1192415 (CDC7); rs10483727 (SIX1/SIX6), rs9607469 (CARD10); ii) CCT with rs1192415; iii) IOP with rs1900004 and iv) AL with rs1900004 and rs1063192 (CDKN2B). We were able to replicate previously known interactions between ATOH7-SIX6 and SIX6-CDKN2B along with few novel interactions between ATOH7—CDC7 and SIX6 with genes including CARD10 and CDC7. In summary, our results suggest that a probable interaction among the candidate genes for QTs, play a major role in determining the individual’s susceptibility to POAG.

Incidence and Management of Glaucoma in Vogt Koyanagi Harada Disease.

Purpose:To analyse the prevalence, incidence, and risk factors of glaucoma in Vogt Koyanagi Harada (VKH) disease and study the changes in visual acuity and intraocular pressure (IOP) with treatment. Materials and Methods:Retrospective chart analysis of 448 eyes of 224 patients of Indian origin diagnosed with VKH disease from January 1990 to December 2013, who had a minimum follow-up of 3 months was performed. Results:Seventy-one eyes (15.8%) developed sustained elevation in IOP. The prevalence of glaucoma at presentation was 15.8% and the cumulative incidence of glaucoma was 11.7%. The mechanisms of glaucoma were open-angle glaucoma in 46 eyes, (64.8%), angle closure in 21 eyes (29.6%), and of combined mechanisms in the remainder (4 eyes, 5.6%). Acute angle-closure crisis developed in 9 eyes (12.6%). Uveal effusion (odds ratio 9.47; confidence interval, 4.08-20.03) and increased number of recurrences (odds ratio 1.31; confidence interval, 1.13-1.53) were found to be significant risk factors for the development of glaucoma. Successful control of IOP was achieved in 64% at 12 months using medical/ laser treatment for glaucoma and was 50 % at 12 months following surgical management. Conclusions:Glaucoma is a frequent complication of uveitis in VKH disease. Presence of uveal effusion and increased number of recurrences of inflammation are significant risk factors.

Prevalence of the optic disc anomalies in the adult South Indian population

Purpose To determine the prevalence of congenitally abnormal disc (all anomalies) in an adult population in southern India. Methods Subjects aged ≥40 years (n=6013) underwent a complete ophthalmic examination. Optic disc anomalies were diagnosed according to the definitions given in the article. Results Optic disc anomalies were found in 81 eyes of 66 (1.1%, 95% CIs 0.00834 to 0.01361) patients. The prevalence of each anomaly in the descending order was peripapillary myelinated nerve fibre (0.28%), epipapillary glial tissue on the optic disc (0.28%), peripapillary vascular loops (0.16%), tilted disc (0.09%), optic disc coloboma (0.08%), optic nerve hypoplasia (0.04%), optic disc pit (0.04%), optic disc pigmentation (0.03%), optic nerve head drusen (0.03%), Bergmeister’s papilla (0.03%), optic disc pit and coloboma (0.01%). Conclusions The prevalence of optic disc anomalies is 1.1% in the adult South Indian population.

Management of Elevated Intraocular Pressure Associated With Subluxated/dislocated Lenses by Combining Trabeculectomy With Adjunctive Mitomycin C With Lensectomy, Vitrectomy, and Scleral Fixation of Intraocular Lens

Aim:To evaluate the short-term outcomes of lensectomy, combined with vitrectomy, scleral-fixated intraocular lens (SFIOL), and trabeculectomy with adjunctive mitomycin C (MMC) in patients with subluxated/dislocated crystalline lenses with associated elevated intraocular pressure (IOP). Materials and Methods:This retrospective case series included 51 eyes of 51 patients who underwent lensectomy, vitrectomy, and SFIOL combined with trabeculectomy with MMC between 2003 and 2012. The main outcome measures assessed were IOP, change in visual acuity, IOP-lowering medications, and the complications and reoperation rates. Results:The most common etiology observed was blunt trauma in 35 eyes (68.6%). Glaucomatous optic neuropathy was detected in 13 eyes (25.49%) preoperatively. The IOP reduced significantly from a preoperative mean of 26.3±11.5 mm Hg to 13±4.6 mm Hg (P<0.001) at the final visit. The mean preoperative number of IOP-lowering medications of 2.9±0.8 reduced to 0.3±0.7 at last follow-up (P<0.001). The best-corrected visual acuity (Snellens) improved significantly from 20/600 to 20/60 (P<0.001). Complete success defined as IOP⩽21 mm Hg without medications was achieved in 93%±5% and 80%±13% at 1 and 2 years, respectively. Major postoperative complications included retinal detachment in one eye and SFIOL dislocation in another. Conclusions:The technique of combining SFIOLs with trabeculectomy with adjunctive MMC in the management of subluxated/dislocated lenses resulted in good IOP control and improvement in visual acuity.

Topiramate-induced secondary angle closure

Acute angle closure (AAC) is a serious complication of topiramate therapy. A 43-year-old woman developed simultaneous bilateral AAC following use of topiramate. In another centre, patient was treated as a pupillary block angle closure which included oral acetazolamide. On examination at our centre however, a diagnosis of topiramate-induced secondary angle closure was made but delayed recognition lead to iris atrophy and cataract; both changes affected the quality of vision after recovery. In this case report, we highlight the fact that a careful clinical approach can prevent ambiguity in diagnosis and differentiation from primary angle closure. Awareness among health professionals can also help in early recognition thus evading serious ocular complications.