Indian Journal of Ophthalmology

GUEST EDITORIAL
Year
: 2006  |  Volume : 54  |  Issue : 3  |  Page : 147--148

Angle closure and India


Devindra Sood, NN Sood 
 Glaucoma Imaging Centre, New Delhi - 110 049, India

Correspondence Address:
Devindra Sood
Glaucoma Imaging Centre, P-13 South Extension Part 2, New Delhi - 110 049
India




How to cite this article:
Sood D, Sood N N. Angle closure and India.Indian J Ophthalmol 2006;54:147-148


How to cite this URL:
Sood D, Sood N N. Angle closure and India. Indian J Ophthalmol [serial online] 2006 [cited 2022 Dec 2 ];54:147-148
Available from: https://www.ijo.in/text.asp?2006/54/3/147/27063


Full Text

It is estimated that by the year 2010, 60.5 million people would be burdened by glaucoma and that by 2020 there would be 79.6 million sufferers. Forty-seven per cent of the glaucomas worldwide would be in Asia with more than 75% being angle closure.[1] At present twelve million Indians are affected by glaucoma accounting for 12.8% of the blindness in the country.[2]

Hospital-based data from India report primary open angle glaucoma (POAG) to be as common as primary angle closure glaucoma (PACG), with 45 to 55% of primary glaucomas being PACG.[3],[4] In the glaucoma clinic of an eye hospital, 45.9% of all primary adult glaucomas were of the angle closure type.[4] Of these 24.8% had acute angle closure glaucoma, 31.2% had subacute and 44% had chronic glaucoma. Since then the definition of angle closure glaucoma has undergone a change. Angle closure is now described as an anatomical disorder where symptomatology does not specify the involved mechanism.[5] In Asian eyes, the majority of the closures arise from a combination of a pupil block and nonpupil blocking mechanisms.[6] Primary angle closure suspect (occludable angle), primary angle closure (PAC) and PACG are now distinct entities reflecting the severity of the disease.[7],[8],[9]

More than 80% of the chronic angle closures have no significant symptoms.[4] Three landmark studies conducted in India, the Vellore eye survey reported a prevalence of 4.32% for PACG. Occludable angles accounted for 10.3% in the population.[10] The Andhra Pradesh eye disease survey reported a prevalence of 0.71% for PACG and occludable angles accounted for 1.41% of the study population.[11] The Aravind comprehensive eye survey reported a prevalence of 0.5% for PACG (95% CI 0.3 - 0.7).[3] Despite near similar study populations, a meaningful comparison is difficult because of the differences in patient selection, methodology and definitions used.

Screening for angle closure glaucoma appears tempting to minimize the loss of vision, but it is still not a viable option. In fact glaucoma does not fulfill all the criteria laid down by the World Health Organization to justify a population-based screening. Also, available resources (trained ophthalmologists, instrumentation and time) and the economics of glaucoma detection and treatment are not uniform. Every step in glaucoma management - investigation / treatment could further burden these scarce resources, which if judiciously used could actually benefit more people.[11] Case detection in the clinic is perhaps the best approach as of now. Improved detection with simple tests (flashlight test and von Herrick's test) and confirmation on gonioscopy play a key role in diagnosis.

It is heartening to note three articles on various aspects of angle closure in this issue of the Indian Journal of Ophthalmology. Two of these detail case detection in the clinic. The study by Al-Mubrad et al . looks at a rapid, noninvasive method for screening in the clinic while Kaushik et al . emphasize gonioscopy as a cost-effective tool for identifying signs of angle closure.

Drugs prescribed for diverse conditions can aggravate closure; particularly in those with narrow angles and or a previously undiagnosed angle closure.[12] In our concern for primary angle closure we often tend to neglect secondary angle closure. Desai et al . emphasize the effect of one such drug.

In conclusion, in India asymptomatic chronic angle closure glaucoma mimicking POAG is common. Gonioscopy is the confirmatory test and must become a part of the routine workup for our glaucoma patients and suspects. Provocative testing may play a supportive role in asymptomatic occludable angles . The definitive treatment for angle closure is a laser iridotomy. The efficacy of the iridotomy is dependant on the underlying mechanism causing closure and also the stage of the disease.[13] Following the iridotomy, angle closure is treated medically or surgically in the same manner as open angle glaucoma. Treatment of the fellow eye with a laser iridotomy is mandatory.

References

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4Sihota R, Agarwal HC. Profile of the subtypes of angle closure glaucoma in a tertiary hospital in North India. Indian J Ophthalmol 1998;46:25-9.
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11South East Asia Glaucoma Interest Group. Asia Pacific Glaucoma Guidelines. SEAGIG: Sydney; 2003.
12Mandelkorn R, Obert M. Nonsteroidal drugs and glaucoma In : Robert R, Shields M, Theodore K. The Glaucomas Volume II Mosby: 1996.
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