Friday, August 7, 2009

Surgery Relieves Migraines But Limitations Noted

For the 30 million Americans seeking relief from migraine headaches, relatively minor surgical procedures reported in the August 2009 edition of the journal Plastic and Reconstructive Surgery could be a solution. Although, a close look at the data suggests limitations that should be considered.

A blinded, controlled clinical trial was designed to demonstrate the efficacy of surgical deactivation of 3 common migraine headache trigger sites. In 75 patients with confirmed moderate-to-severe migraine headache, trigger sites were identified as located in either frontal, temporal, or occipital regions of the head. A trigger site is where migraine begins and settles, and it corresponds in these cases to regional irritation of trigeminal nerve branches. Average age of patients was 45 years (range 26-76), and there was a mix of those experiencing migraines with and without aura; patient sex was unspecified in the report.

Patients were randomly assigned to receive either actual (n=49) or sham (n=26) surgery in their predominant trigger site, but they were not told (were blinded to) which procedure they would receive. The actual surgeries, performed under anesthesia, generally involved incisions in the identified trigger regions with selective removal of affected nerve and muscle tissues. Sham surgeries (control group) involved the same procedures but without removing any muscle or nerve tissues. The procedures were performed in an ambulatory surgery center and required about one hour each; patients were able to resume usual activities within a week.

Approximately 84% of the actual surgery group and 58% of the sham surgery group had at least a 50% reduction in migraine headaches (frequency, intensity, duration) at the 1-year followup (p < 0.05). Most important, 57% of patients in the actual surgery group reported complete elimination of migraine headache, compared with only about 4% in the sham surgery group (p < 0.001). Compared with the sham surgery group, those receiving actual surgery also demonstrated statistically significant improvements in migraine-specific assessments of quality of life, disability, and other measures, and these were not dependent on the trigger site or presence versus absence of aura. The most common surgical complication was slight hollowing of the temple in the group with temporal migraine headache. As a side benefit, the actual surgery for frontal migraine was similar to a traditional cosmetic “forehead lift,” thus alleviating frown lines and creating a more youthful look.

Caveats & Limitations: This study demonstrates that surgical deactivation of peripheral migraine headache trigger sites may be an effective alternative treatment for select patients who suffer from frequent migraine headaches that are difficult to manage with other therapies. However, it also is important to look at the data from this trial in ways that are important to patients.

The use of invasive sham surgeries in human clinical trials has been questioned on ethical grounds; however, this trial is an example of how without such a control group the benefit of a new procedure might be overstated. Prior research, using the same surgical procedures but without a sham-surgery control group, had reported a 92% response rate (50% reduction of migraine symptoms). In this present trial, the surgical-response rate is diminished by the fact that nearly 3 of every 5 patients receiving the sham surgery procedure had a favorable response, which the researchers attributed to possible placebo effects or, perhaps, merely undermining tissues during the sham procedure may have altered neurosensory function in a beneficial way, but this is unknown for certain. To explain treatment failures in the actual surgery group, of which there were 16.3% (8/49), the researchers suggest the possibility of misdiagnosed trigger sites or the presence of multiple trigger sites that were not all treated.

In any case, the available data do indicate a complete migraine-remission rate attributable to the actual surgery of 53% (57% [actual]-4% [sham]), which gives a number-needed-to-treat (NNT) of about 2 (1/.53). In other words, 1 of every 2 properly diagnosed patients undergoing actual surgery might be expected to have a complete remission of their migraines at 1 year. Beyond complete relief it is difficult to predict how many might partially benefit because so many patients having the sham surgery experienced a 50% reduction of symptoms. Also, it is important to acknowledge that any surgical procedure carries some risk; although, adverse events reported in this trial were minor.

Some of the subgroup sizes in this trial, especially for sham surgery, were quite small and may not have had statistical power to fully delineate significant treatment or placebo effects. Further research enrolling larger numbers of patients could be advantageous; meanwhile, insurance plans might consider the procedure experimental and be unwilling to cover costs. There also is a question of long-term benefits beyond the 12 months that were assessed in this trial. In a press release, Bahman Guyuron, MD, developer of the technique and lead researcher, said he has a “large number of patients who have remained symptom-free for more than 5 years.” However, it would be helpful if this number could be better defined and substantiated.

Reference: Guyuron B, Reed D, Kriegler JS, et al. A placebo-controlled surgical trial of the treatment of migraine headaches. Plast. Reconstr. Surg. 2009(Aug);124(2):461-468. [See abstract.]