Clinical features differentiate retinoblastoma, Coats’ disease

BOSTON — Physicians can distinguish between Coats’ disease and retinoblastoma in the clinic if they know what features to look for, according to one expert.

“You have to look at the pupillary reflex, the appearance of the anterior chamber, the clarity of the vitreous, the color of the subretinal fluid, the caliber and course of the retinal vessels, and the macular appearance,”Jerry A. Shields, MD, told colleagues at Macula 2015.

In Coat’s disease, patients have more of a yellow pupillary reflex, and the anterior chamber is clear, even though cholesterolosis bulbi can form. The vitreous is classically clear, but the subretinal fluid may be yellow with cholesterol deposits. Uniformly dilated blood vessels form aneurysmal irregular dilatations, and blood vessels disappear into the ora serrata.

In retinoblastoma, patients have more of a white pupillary reflex. The anterior chamber is clear, but the vitreous may be hazy and the subretinal fluid is white-gray. Blood vessels are uniformly dilated but not aneurysmally, and in the exophytic type of the disease, they disappear into the substance of the underlying tumor.

In macular disease, both diseases cause abnormal pupillary reflex. According to Shields, whereas there is yellow exudation and no feeder vessels seen in Coats’ disease, there is white tumor and dilated feeding artery and vein draining into the lesion seen in retinoblastoma.

Retinoblastoma and Coats’ disease look similar and have similar clinical features superficially, Shields said, “but when you look with close scrutiny, there’s a big difference in most cases.”

Disclosure: Shields has no relevant financial disclosures.