Blindness and Low Vision in a Tertiary Ophthalmologic Center in Thailand

Abstract

Purpose:To determine the causes of blindness and low vision in patients consulting a tertiary ophthalmologic center in northern Thailand.Methods: The study population included 2,951 new consecutive patients from the Department of Ophthalmology at University Hospital in Chiang-Mai, Thailand. Main outcome measures were blindness and low vision, which were defined according to World Health Organization criteria.Results: Of 2,951 patients, 369 (12.5%) had blindness and/or low vision (bilateral blindness in 73, unilateral blindness in 129, bilateral low vision in 77, and unilateral low vision in 90). Of the etiological causes of visual loss, age-related ocular disease was the most frequent (128 patients [35%]) followed by infections (66 patients [18%]) and trauma (43 patients [12%]). Although infections and trauma were the predominant causes of blindness, age-related disorders were frequently found in patients with low vision. Of anatomical sites, the lens (134 patients [36%]) was the main location of visual loss, closely followed by disorders of the retina and/or uvea (126 patients [34%]). Blindness and low vision were considered avoidable in 70% of cases. Of 73 patients with bilateral blindness, 14 had active cytomegalovirus retinitis, accounting for 19% of all patients with bilateral blindness. Conclusion:The most common causes of blindness and low vision in a tertiary center in northern Thailand were age-related ocular disorders and infections, which were predominantly cases of cytomegalovirus retinitis in human immunodeficiency virus-infected patients.RETINA 27:635-640, 2007

Uveitis in a tertiary ophthalmology centre in Thailand

“…This relatively high percentage of infectious uveitis was mainly due to the large amount of CMV retinitis in HIV-infected patients The prevalence of HIV-associated uveitis (30% of all with uveitis) is higher than in the West and is influenced by the high number of HIV-positive people in the Thai population and also by the fact that ophthalmological treatment is concentrated in tertiary centres such as ours 11 12 18. However, this percentage is similar to those in a study from the USA in the pre-HAART era (11–30%) 11 19 20.…”

Telemedicine Diagnosis of Cytomegalovirus Retinitis by Nonophthalmologists

“…In fact, because the study site is a tertiary referral center, it is likely that even the 35.6% prevalence estimate is higher than what would be observed at a typical HIV clinic in Thailand. 7,8,16 At a 10% prevalence, which is a more realistic estimate for a nontertiary health care setting, the mean positive predictive value would be 61.9% for a diagnosis of CMV retinitis present and 11.5% for a diagnosis of unknown, and the mean negative predictive value would be 97.9%. These results demonstrate that a telemedicine program with nonexpert graders would be effective in ruling out CMV retinitis in patients who do not have the disease.…”

“…At a tertiary ophthalmologic center in Chiang Mai, Thailand, CMV retinitis was found in 33% of HIV-positive patients who received screening and was one of the leading causes of blindness among all patients seen at the clinic. 7,8 In this resource-poor setting, patients often have severe disease when they first present to an ophthalmologist despite receiving HAART, which is suggestive of inadequate screening. 9,10 There are significant challenges to screening the population at risk for CMV retinitis.…”

HIV/AIDS in the Developing World

“…31 In a 2007 study from Thailand, CMV retinitis was the cause of bilateral blindness in nearly 20% of all patients. 58 Recent estimates indicate that India is home to 2.4 million HIVpositive people, lower than earlier estimated. 3,59 In earlier studies, CMV retinitis and HIV retinopathy seemed to be less prevalent in India than in western countries, reported between 17% and 20% and between 7% and 15%, respectively.…”