Contralateral trigeminal neuralgia as a false localizing sign in intracranial tumors

Three cases of contralateral trigeminal neuralgia as a false localizing sign in intracranial tumors are reported. In each patient (meningioma, 2 cases; cholesteatoma, 1 case) the tumor was asymptomatic, so that intracranial tumor had not been suspected preoperatively. In all cases, tumors were large and firm. The tumor was supratentorial in two cases. In one case, a cortically mediated mechanism may have caused the neuralgia, whereas in the remaining two cases distortion and displacement of the brain stem and compression of the contralateral Meckel's cave would explain the trigeminal nerve signs.