Detection of small trigeminal neurinomas.

Four cases of trigeminal neurinoma are reviewed with particular attention to clinical signs and symptoms, lumbar puncture, electroencephalogram, brain scan, plain skull and tomographic radiographs, and angiographic and pneumoencephalographic findings. Pneumoencephalography, with special tomographic projections to identify various portions of the trigeminal nerve, delineated the tumor in all cases. Tumor removal was complete in three patients and nearly complete in the fourth. There was no operative morbidity or mortality.