Meningiomas of Meckel's cave.

A retrospective review of 12 cases of meningioma of Meckel's cave involving the Gasserian ganglion or the trigeminal posterior root (or both) seen at the Mayo Clinic during a 20-year period suggested three clearly defined clinical groups. One group (the largest) had typical trigeminal neuralgia and an excellent prognosis after the removal of the easily detachable mass that was impinging on the ganglion. A second group, with meningiomas en plaque embedded in the ganglion, had a history of atypical trigeminal face pain without neurological deficit, but the prognosis for pain relief was not as good as in the previous group. A third group had a history of face dysesthesias and pain, objective trigeminal sensory loss, and multiple cranial nerve deficit; these patients had meningiomas with histological signs of mitotic activity and a poor prognosis, with return of intractable pain and recurrence of the tumor.