These lesions appear to be at the level of the choroid and deep retina. Posterior vitreous cellular reaction is always present. Vascular sheathing, disc edema and CME may also appear. As the lesions mature, they may enlarge, resulting in RPE atrophy. In the late stages, RPE hyperpigmentation and retinal arteriolar narrowing can appear, and the disc may be pale.
Some patients develop disc neovascularization and vitreous hemorrhage.
Angiography reveals marked disc and cystoid macular leakage. The lesions stain relatively poorly, or not at all. The ERG is usually abnormal in both rod and cone function. Because of the vision-threatening nature of this disease, systemic steroids and sometimes steroid sparing medications such as cyclosporine are necessary. The response is usually good.