Optic nerve changes in chorioidal malignant melanoma.

The optic nerve has been investigated in 11 cases of chorioidal malignant melanoma. 10 cases showed central fascicular degeneration surrounded by a rim of myelinated nerve fibers. Microglia was regularly found demarkating the central changes and often within the demyelinated areas. The changes were found within all quadrants of the nerve and without any apparent correlation with defects in the visual field.