Microvascular decompression for trigeminal neuralgia. A five-year follow-up study.

A series of 72 patients with typical trigeminal neuralgia who underwent microsurgical exploration of the trigeminal nerve in the posterior fossa is analyzed. The operations were performed between 1977 and 1980 with an average follow-up period of 4.94 years. Seventy-eight percent of the patients have remained free of pain after the operation. Of the 16 patients (22%) that were either not relieved of their pain or had a recurrence, two are well-controlled with medical treatment and the rest have required a variety of surgical procedures (mostly radiofrequency rhizotomy) for pain relief. Recurrences were significantly more common in females. There was no relationship between recurrence rate and the age of the patient or the duration of the symptoms before surgery. Definite compression of the trigeminal nerve at the root entry zone by an arterial loop singly or in combination with other arteries or a vein was found in 82% of the patients. The recurrence rate in this group was 19%. Definite compression by a vein was found in seven patients and the pain recurred in four (47%), a significant difference. There was no death or disabling stroke in this series, but persistent unilateral hearing loss occurred in a total of 14 patients (19%), with complete deafness in the ipsilateral ear in five patients (7%). In addition, two patients suffered mild but persistent ataxia of gait and two patients intermittent diplopia. These results are compared with the results of other reported series.