Primary malignant melanoma of the optic nerve sheath: a case report.

Background: Primary malignant melanoma of the optic nerve or its sheath, without choroidal involvement, is rare.

Case Description: A case of primary malignant melanoma of the optic nerve in a 67-year-old man is presented.

Conclusions: With a preserved vision, normal fundoscopy makes the correct preoperative diagnosis a real challenge.