Intracranial optic nerve germinoma.

A 11-year-old boy presented with complaints of diminution of vision in the left eye for three months. On examination, the vision in this eye was reduced to only perception of light. Magnetic resonance imaging revealed a thickened left intracranial optic nerve. The lesion was explored by a pterional craniotomy. At surgery, the left optic nerve was diffusely thickened. The biopsy of a fleshy mass along the optic nerve showed that it was a germinoma on histopathology. Isolated optic nerve germinomas are extremely rare. Exclusive primary involvement of the intracranial portion of the optic nerve by a germinoma has not been reported in the literature. This rare case is discussed and the relevant literature has been reviewed.