Malignant melanoma of the optic nerve
P. De Potter, C. L. Shields, R. C. Eagle Jr, J. A. Shields and J. L. Lipkowitz
Ocular Oncology Service, Wills Eye Hospital, Philadelphia, Pa., USA.
A 67-year-old man was diagnosed as having a melanocytoma of the optic disc
in the left eye. Observation during a 5-year period showed no change in the
lesion. At age 72 years, he had abrupt visual loss to no light perception
in the affected left eye. Clinical examination disclosed little enlargement
of the papillary tumor but ultrasonographic evidence of optic nerve
infiltration. Precontrast magnetic resonance imaging studies disclosed a
hyperintense infiltrative lesion in the enlarged left optic nerve.
Enhancement features of the lesion excluded a hemorrhagic process. The eye
was removed with a 22.5-mm segment of optic nerve. Histopathologic
examination showed a large, necrotic, mixed-cell malignant melanoma
confined to the optic nerve. No choroidal involvement or viable
melanocytoma cells were documented. This case stresses that it may be
difficult to differentiate a melanocytoma from a primary malignant melanoma
of the optic nerve.
