Coats' disease: trends and long-term treatment outcomes in a tertiary referral centre

Background: The long-term treatment outcomes in Coat's disease - particularly in the era of newer pharmacotherapies such as anti-vascular endothelial growth factor (VEGF) agents and depot steroids - are poorly understood. Aim: To describe the clinical features and treatment outcomes of 148 eyes with Coats' disease assessed in a referral centre over 30 years. Materials and methods: We conducted a retrospective chart review of patients diagnosed with Coats' disease between 1 June 1987 and 31 July 2017. The demographic, clinical and treatment data were collected and long-term functional and anatomical outcomes were analysed based on the treatment either with conventional therapy (cryo/laser) or along with adjuvants like intravitreal steroids or anti-VEGFs. Results: The mean age at presentation was 15.22 years (median 11). Familial exudative vitreoretinopathy was the most common referral diagnosis, 76/148 (51.5%), followed by Coats' disease, 37/148 (25%), and retinoblastoma, 35/148 (23.6%). Stage 3B was most common at presentation (31.8%), followed by 2B (22.3%) and 2A (16.9%). A total of 107 patients were treated either with conventional therapy or in combination with adjuvants. The mean follow-up period was 24.95 months. The visual acuity improved from baseline logMAR 2.17 (Snellen-20/2958) to logMAR 1.88 (Snellen-20/1517) at final follow-up (p = 0.004). The improvement in visual acuity was better when the presenting BCVA was <1 logMAR (Snellen 20/200), p = 0.004. No statistically significant change in BCVA was noted between conventional and adjuvant groups, p = 0.5. However, the final anatomical outcome was good in 78/99 (78.8%) in the conventional group and 45/49 (91.8%) in the adjuvant group, respectively (p = 0.046). Conclusion: In this series of patients with Coats' disease over three decades, the use of intravitreal steroids or anti-VEGFs as adjuvants resulted in better anatomical outcomes. A better baseline visual acuity, lower stage of the disease, and older age at presentation were found to be the factors leading to favourable visual outcomes.