A rare benign eye tumour characterised by the presence of glial cells, vascular tissue and sheets of pigment epithelial cells lacking the distribution and organisation of the normal retina and retinal pigment epithelium. The lesion is most commonly found unilaterally as a slightly elevated mass in a peripapillary location but can also occur in the macula or the retinal periphery. It is sometimes associated with neurofibromatosis type 1 or 2, naevoid basal cell carcinoma syndrome, or branchio-oculo-facial syndrome. Patients may be asymptomatic or present with progressive loss of vision. [from
SNOMEDCT_US]