The presence of refractile or non-refractile yellow Gass plaques in the retinal arterioles is near pathognomonic for the disease. Fluorescein angiography may demonstrate leakage in areas remote from the retinal infarctions.
Refractile or non-refractile yellow Gass plaques found within retinal arterioles are highly indicative of the condition, and fluorescein angiography can show leakage in areas away from the retinal infarctions.