Trigeminal neuralgia and hemifacial spasm: treatment by microvascular decompression.

On the basis of observation of 26 patients, we consider that the common cause in trigeminal neuralgia and hemifacial spasm is compression of the nerve-root entry zone at the brainstem by a blood vessel, usually an artery. By mobilising the vessel, and securing it away from the nerve, symptoms were relieved in 16 of 17 patients with trigeminal neuralgia and in seven of nine patients with hemifacial spasm for a follow-up period of up to four years. Trigeminal microvascular decompression had few complications, but three patients treated for facial hemispasm had postoperative deafness and one had a probable small brainstem infarct. The major advantage of this surgical approach is that is possible to relieve the symptoms without facial anaesthesia or paralysis.