Elevated vascular endothelial growth factor level in Coats' disease and possible therapeutic role of bevacizumab

Purpose: To compare intraocular vascular endothelial growth factor (VEGF) level in patients with and without Coats' disease, and to report a case of Coats' disease that responded to intravitreal injection of bevacizumab. Methods: Intraocular fluid was obtained from four eyes with Coats' disease (subretinal fluid in three eyes and aqueous in one eye) and from five eyes with rhegmatogenous retinal detachment (subretinal fluid in four eyes and vitreous in one eye). Intraocular VEGF level was compared between these two groups. In one eye with stage 2B Coats' disease, macular edema, visual acuity, and intraocular VEGF level were compared before and after intravitreal injection of bevacizumab. Results: Mean intraocular VEGF level in eyes with Coats' disease was 2,394.5 pg/ml, compared to 15.3 pg/ml in eyes with rhegmagenous retinal detachment. In the eye with stage 2B Coats' disease, macular edema was reduced after bevacizumab injection, and the visual acuity improved from 0.05 to 0.2. Intraocular VEGF level decreased from 1247 pg/ml to 20.4 pg/ml 1 month after the injection. Conclusion: Coats' disease is associated with increased intraocular VEGF level. Bevacizumab may be a valuable adjunctive treatment for Coats' disease.