Outcomes of Surgical Treatment of Migraines: A Systematic Review & Meta-Analysis

Background: Migraine surgery at 1 of 6 identified “trigger sites” of a target cranial sensory nerve has rapidly grown in popularity since 2000. This study summarizes the effect of migraine surgery on headache severity, headache frequency, and the migraine headache index score which is derived by multiplying migraine severity, frequency, and duration. Materials and Methods: This is a PRISMA-compliant systematic review of 5 databases searched from inception through May 2020 and is registered under the PROSPERO ID: CRD42020197085. Clinical trials treating headaches with surgery were included. Risk of bias was assessed in randomized controlled trials. Meta-analyses were performed on outcomes using a random effects model to determine the pooled mean change from baseline and when possible, to compare treatment to control. Results: 18 studies met criteria including 6 randomized controlled trials, 1 controlled clinical trial, and 11 uncontrolled clinical trials treated 1143 patients with pathologies including migraine, occipital migraine, frontal migraine, occipital nerve triggered headache, frontal headache, occipital neuralgia, and cervicogenic headache. Migraine surgery reduced headache frequency at 1 year postoperative by 13.0 days per month as compared to baseline ( I2 = 0%), reduced headache severity at 8 weeks to 5 years postoperative by 4.16 points on a 0 to 10 scale as compared to baseline ( I2 = 53%), and reduced migraine headache index at 1 to 5 years postoperative by 83.1 points as compared to baseline ( I2 = 2%). These meta-analyses are limited by a small number of studies that could be analyzed, including studies with high risk of bias. Conclusion: Migraine surgery provided a clinically and statistically significant reduction in headache frequency, severity, and migraine headache index scores. Additional studies, including randomized controlled trials with low risk-of-bias should be performed to improve the precision of the outcome improvements.

Single Incision Approach for Decompression of Greater, Lesser and Third Occipital Nerves in Migraine Surgery

Background The traditional approach for occipital migraine surgery encompasses 3 separate surgical incisions in the posterior neck to decompress the great occipital nerves (GON), lesser occipital nerves (LON) and third occipital nerves (TON). We sought to evaluate a single midline incision approach for decompression of all 6 occipital nerves. Methods Using 10 cadaveric hemi-sides (5 fresh cadaver head and necks). Anatomic landmarks and the location of the bilateral GON, LON and TON were marked according to previous anatomic studies. A single midline 9-cm incision was made and lateral skin flaps were raised to decompress or avulse all 6 nerves. Results The GON and TON were identified 3.5 and 6.2 cm, respectively inferior to a line bisecting the external auditory canal (EAC) and 1.5 cm lateral to the midline. The LON was identified 6-cm inferior and 6.5-cm medial to a line bisecting the EAC in the plane just above the investing layer of the deep cervical fascia until the posterior boarder of the sternocleidomastoid was encountered. The LON had the greatest amount of variation, but was identified lateral to the posterior border of the SCM. Conclusions A single midline incision approach allows for successful identification and decompression of all 6 occipital nerves in migraine surgery.