WASHINGTON – Peripheral neuromodulation effectively managed a variety of craniofacial and headache pain syndromes, with 82% of patients reporting significant pain relief up to 65 months after the surgery in a retrospective study.
While percutaneous neuromodulation surgery is by no means a primary therapy for facial pain or headache, "it is something to keep in mind for patients with intractable pain," Dr. Antonios Mammis said at the annual meeting of the Congress of Neurological Surgeons.
Dr. Mammis, a resident at the Neurological Institute of New Jersey in Newark, presented a review of 99 patients who underwent occipital or trigeminal branch stimulation for a variety of craniofacial pain syndromes. The study won the group’s Ronald Tasker Award for Research in Pain Management. He conducted the study while he was a resident at Long Island Jewish Medical Center, New Hyde Park, N.Y.
The review encompassed procedures done by a single neurosurgeon from 2004 to 2011. During the review, Dr. Mammis reclassified each patient’s symptoms according to the International Classification of Headache Disorders, Second Edition. Of the 99 patients, 74 were female. The mean age at surgery was 43 years (range, 11-68 years).
Chiari malformation type 1 was the most common classification (28 patients). This was not a surprise, since the neurosurgeon worked at a Chiari referral center.
Other pain classifications included migraine with or without aura (24), chronic posttraumatic headache attributed to mild head injury (11), occipital neuralgia (8), postcraniotomy headache (7), chronic cluster headache (5), headache secondary to ischemic stroke (5), other terminal branch neuralgias (5), cervicogenic headache (4), hemicrania continua (1), and acromegaly (1).
All patients underwent a 4- to 7-day treatment trial, with a bilateral lead placement performed under local anesthesia with intravenous sedation. The surgeon used surface anatomy and fluoroscopy to determine lead placement. During the trial, patients kept a headache diary noting frequency, duration, and severity.
While percutaneous neuromodulation surgery is by no means a primary therapy for facial pain or headache, "it is something to keep in mind for patients with intractable pain," said Dr. Antonios Mammis.
After the trial period, 79 patients (80%) reported significant pain relief, which was defined as at least a 50% decrease in pain as rated on a visual analog scale. These patients went on to have a permanent neuromodulator implanted. Of these, 56 received only occipital leads, 12 received only trigeminal leads, and 11 had leads implanted on both nerve branches.
Most of the headache syndromes responded equally well to the neurostimulators. At the last follow-up, which ranged from 1 to 65 months, 65 (82%) reported continued use of the stimulator and continued to report significant pain improvement.
At that time, stimulators were still being used in 15 of 18 Chiari malformation patients, 19 of 21 migraine patients, 7 of 7 occipital neuralgia patients, 6 of 7 postcraniotomy patients, 4 of 4 cluster headache patients, 1 of 3 ischemic stroke patients, 1 of 4 terminal branch neuralgia patients, 3 of 3 cervicogenic headache patients, and the one patient with hemicrania continua. The single acromegaly patient received a stimulator, but did not have long-term pain relief.
Complications arose in 10 patients. Four of these were lead migrations that required revision, which is "a problem that is very easily corrected," Dr. Mammis said. Six patients acquired an infection; three were wound erosions and three were surgical site infections without erosion. "All of these leads were explanted and revised," he said. There were no infections after revision.
Nearly a quarter of the patients (22%) asked for a cosmetic revision. "This was primarily done because they could see or feel the lead," Dr. Mammis said. "These were not infected leads, and there were no infections after these revisions."
Dr. Mammis had no financial disclosures.