Ninety-six patients underwent percutaneous radiofrequency coagulation (RC) of the Gasserian ganglion for relief of trigeminal neuralgia between 1973 and 1978. Fifty-two percent of patients who were followed for 5 years were free of recurrence after a single RC procedure. Factors predicting clinical results were sought from initial historical and demographic data. Age, sex, duration of illness, and previous response to medication were unrelated to outcome. Patients previously treated by open surgery appeared to receive less benefit from subsequent RC. The RC procedure seemed more effective in the treatment of patients with classical tic douloureux than in those with atypical features. The degree of sensory loss created by RC was associated with the clinical outcome. Patients acquiring dense sensory deficits demonstrated a reduced risk of recurrence (p = 0.006): 25% of patients with dense sensory loss and 55% of those with a partial deficit developed a recurrence by 5 years, whereas all patients without initial sensory loss suffered a recurrence by 5 years.