Optic disc melanocytoma, also known as magnocellular nevus, is a rare benign tumor that often develops within or close to the optic nerve head and occasionally involves the retina and choroid.
The majority of melanocytomas do not result in loss of visual acuity; however, about 25% of affected eyes experience minor vision loss. Retinal exudation involving the macula is the principal factor that leads to visual loss. Other risk factors include retinal extension and subretinal fluid. Although it is uncommon, malignant transformation, spontaneous tumor necrosis and central retinal vein obstruction