Comparison of outcomes of transnasal sphenopalatine ganglion and ultrasound-guided proximal greater occipital nerve blockades in chronic migraine

Background & Objective: A need exists for prophylactic treatment options for chronic migraine. Our aim was to evaluate and compare the effect of greater occipital nerve (GON) and transnasal sphenopalatine ganglion (SPG) blockade on headache days, responder rate, attack severity, attack frequency, and medication overuse in patients with chronic migraine. Methods: This was a retrospective study. The GON blockade was performed at the proximal level under ultrasound guidance with 1.5 cc 0.5% bupivacaine, and the SPG blockade was performed transnasally with 0.5 cc 0.5% bupivacaine applied for 30 minutes with swab sticks. Patients who completed bilateral blocks applied in four weekly sessions were included in the analysis. Results: Seventy patients (GON=37, SPG=33) were included in the study. Both groups showed a significant improvement in the number of days with headache, severity of attacks, and frequency of attacks at the first-and third-month follow-up visits compared to the baseline (p<0.001). Responder rates were similar at the first-and third-month follow-up visits (r= 3.707, p=0.054; r=0.071, p=0.790, respectively). At the third-month follow-up, the prevalence of medication overuse decreased from 78% to 13% in the GON group and from 57% to 9% in the SPG group, and these differences were statistically significant (p<0.001 for both groups). No significant difference was noted in efficacy between the treatment groups (p=0.714). No significant adverse effects occurred in either group. Conclusion: Both proximal GON blockade and minimally invasive SPG blockade are effective and safe options for prophylaxis in patients with chronic migraine.