Abnormal choroid morphology Dark choroid 2016-11-29T11:49:16Z A fluorescein angiographic finding of absence of the normal background fluorescence (a dark choroid). The cause of dark choroid is thought to relate to the deposition of an abnormal material (lipofuscin) in the retinal pigment epithelial cells. Fluorescein angiography should no longer be used for diagnosis of Stargardt disease. Abnormal fundus fluorescein angiography