Coats disease is an idiopathic condition characterized by dilated and stretched vessels with intraretinal and subretinal exudates that generally occurs in both children and adults, predominantly males.
Despite reports of being associated with retinitis pigmentosa, Senior-Lohen Syndrome, Turner’s Syndrome, Hallermann-Streiff Syndrome, no definite connection has been made between other systemic or ocular conditions and Coats Disease, and there is no evidence to suggest genetic transmission.
The retina will have a yellow color, but the fluid in the retina will be clear. The typical fundus appearance is that of a localized, liquid rich, yellow subretinal exudate associated with vascular anomalies including sheathing, dilated twisted and turned vessels, stretched-out vessels that appear dilated, zones of capillary drop-out, and neovascularization.
The clinical course is variable, but generally progressive. Exacerbation and inactive stages occur over time. Spontaneous remissions are the exception, but can occur. Serous retinal detachment, iridocyclitis, cataract, and secondary neovascular glaucoma can be complications.
The differential diagnosis includes retinoblastoma, hyperplastic primary vitreous, retinopathy of prematurity, toxocariasis, sickle cell retinopathy, Eales Disease, familial exudative vitreo-retinopathy, cavernous hemangioma, leukemia and anemia, Norrie’s Disease, and any vasculopathy producing exudation.
Treatment options include laser photocoagulation and cryo therapy. Draining of subretinal fluid may also be required with laser or cryo therapy. Vitrectomy with internal drainage of subretinal fluid, vasoablative procedures, intraocular tamponade with gas or silicone oil may also be needed.