Comparison of the long-term results of microvascular decompression and percutaneous trigeminal neurolysis for the treatment of trigeminal neuralgia

Abstract

Introduction: The treatment of medically refractory trigeminal neuralgia has progressed greatly in the last quarter of the 20th century. Excellent relief of the severe pain produced by this condition can be achieved either with the Jannetta microvascular decompression (MVD) operation or via percutaneous neurolytic procedures (PTN) using radiofrequency thermocoagulation (RFL) or glycerol chemoneurolysis (GLY). Methods: We report here the initial results and long-term follow-up data on 702 patients operated upon over a 20-year interval between 1974 and 1994. The number of patients who had MVD is 406 and 352 had 536 PTN procedures. The number of patients treated via RFL is 126 and 242 using GLY. Obviously, some patients had multiple procedures and are in more than one treatment category. The average elapsed time since surgery was 167 months (13.9 years) at the time of last follow-up, and all patients had a minimum of 2 years follow-up at the time of data acquisition. Follow-up was accomplished by questionnaires sent to the patient, their family, or their physician as well as by telephone interviews and record review. Results are graded excellent if the patient is pain-free and off medication, good if pain-free with need for medication at times, but without medication side effects (all were medically intractable preoperatively), fair if the patient requires medications but has breakthrough pain or side effects from the medication, and poor if still with pain. Excellent and good results are considered successes; fair and poor results are considered failures. Results: MVD initially produced 91% excellent results, 6% good results, and failed in 3%. On long-term follow-up, 66% were excellent and 15% good for an 81% success rate. PTN using RFL initially produced 87% excellent results, 6% good, and failed in 7%, while glycerol produced 83% excellent and 9% good results with 8% failures. Thus, both achieved 92–93% initial success. In long-term follow-up, RFL had 71% excellent, 10% good for an 81% success rate. Glycerol had 52% excellent and 12% good results for a 64% long-term success rate. The average time for recurrence with either procedure was 18–19 months. Conclusions: The initial success with all three approaches is equal at 91–93%. The long-term successes for RFL and MVD are also equal at 81% while glycerol has a 64% success indicating more frequent recurrences. Complications with MVD could be serious or even life threatening (1%), such as cerebellar hemorrhage or edema. A number of transient cranial nerve deficits were also seen with a 2% chance of permanent ipsilateral hearing loss. These complications were not seen with PTN, but meningitis and intracerebral hemorrhage occurred in rare cases. Being destructive, PTN procedures intentionally reduced fifth nerve function. RFL was associated with annoying dysesthesia in 22% of our patients, 2% anesthesia dolorosa, and 1.2% corneal anesthesia. GLY produced only 2–4% annoying dysesthesia and 0.3% anesthesia dolorosa. Both procedures are effective ways to treat trigeminal neuralgia. We recommend MVD for younger, better risk patients and PTN for patients who are medically infirm or older (over age 65 to 70). We prefer GLY as the percutaneous procedure of choice since it is easier to treat recurrences by repeating the procedure than it is to treat dysesthetic pain and annoying paresthesias.