Bevacizumab for Coats' disease with exudative retinal detachment and risk of vitreoretinal traction

Aim To evaluate the effect of supplemental intravitreal bevacizumab for management of Coats' disease. Methods Retrospective analysis of eight patients with Coats' disease manifesting total or partial exudative retinal detachment where the retinal telangiectasia was treated with standard laser photocoagulation and/or cryotherapy plus additional intravitreal bevacizumab (1.25 mg/0.05 ml). Results The mean patient age was 88 (range 7-240) months and 63% were male. Coats' disease was classified as stage 2 (n = 1, 12%), 3a (n = 3, 38%) and 3b (n = 4, 50%). Features included retinal detachment (n = 8, 100% with mean detachment extent involving 8 clock hours), telangiectasia (n = 8, 100% with mean extent of 8 clock hours), peripheral retinal ischaemia on fluorescein angiography (n = 7, 88%) and no evidence of neovascularisation. Treatment consisted of cryotherapy (n = 8, 100%), laser photocoagulation (n = 4, 50%) and bevacizumab intravitreal injection (n = 8) with median number of one injection per eye (mean 1.75, and range 1-4 injections). After a mean follow-up of 8.5 months, resolution of retinopathy (n = 8, 100%), Coats'-related subretinal fluid (n = 8, 100%) and retinal exudation (n = 6, 75%) was noted. However, vitreous fibrosis developed (n = 4, 50%) at a mean of 5 months following a mean of 1.75 bevacizumab injections with three (38%) evolving into traction retinal detachment. Conclusion Coats' disease treated with intravitreal bevacizumab in addition to standard therapy can develop to vitreoretinal fibrosis and potentially traction retinal detachment. These tractional features are not often found in Coats' disease treated with standard measures without bevacizumab. Caution is advised in the use of bevacizumab for patients with Coats' disease.