Achieving greater occipital nerve (GON) block in patients with chronic migraine was found to be comparably effective using a proximal or a distal ultrasound (US)-guided technique for alleviating headache intensity, reducing the number of headache days, and improving sleep interruption all in the short term, with the proximal GON technique offering more sustained analgesic benefits, according to a study published in Regional Anesthesia and Pain Medicine.
The study included participants with refractory chronic migraines who were randomly assigned to receive a proximal or distal US-guided GON block with bupivacaine and methylprednisolone acetate (n=40). The primary outcome was the difference in numeric rating score (NRS) for headache intensity at 1 month; secondary outcomes included effectiveness, performance, and safety of both approaches.
Both techniques were found to be associated with significant reductions in NRS pain scores at 24 hours and 1 week post-procedure. Participants who had received GON block using the proximal approach reported a significant reduction in NRS pain score at 1 month and 3 months compared with baseline.
There were no significant differences in NRS scores between the proximal and distal cohorts at any of the follow-up time points.
At 1 month, participants in both groups reported a significant reduction in the number of headache days per week. In the distal group, the number of headache days dropped from 6.40 to 5.50; in the proximal group, it fell from 6.30 to 4.98 at 1 month. At 1 week, participants in both groups reported a significant improvement in sleep interruption.
“With potentially longer-lasting analgesia with equivalent steroid exposure, we recommend using an US-guided proximal GON injection approach first for the treatment of [chronic migraines],” the researchers noted.
Flamer D, Alakkad H, Soneji N, et al. Comparison of two ultrasound-guided techniques for greater occipital nerve injections in chronic migraine: a double-blind, randomized, controlled trial. [published online March 18, 2019]. Reg Anesth Pain Med. doi:10.1136/rapm-2018- 100306