Ultrasound-guided greater occipital nerve block for chronic migraine: a systematic review and meta-analysis

This systematic review and meta-analysis evaluated the safety and efficacy of ultrasound-guided greater occipital nerve block (US-GONB) in managing chronic migraine, comparing outcomes with sham, pulsed radiofrequency (PRF), sphenopalatine ganglion block (SPG), and combination interventions. Following PRISMA guidelines, a comprehensive search of PubMed, Scopus, Cochrane Library, and Web of Science was conducted until February 5, 2025. Eligible studies included clinical trials and observational studies assessing the efficacy and safety of US-GONB in migraine patients. Two reviewers independently performed data extraction and risk of bias assessment. Meta-analyses utilized RevMan 5.4, reporting mean differences (MD) with 95% confidence intervals (CI), applying random- or fixed-effects models based on heterogeneity. Six studies (n = 344) were included: four randomized controlled trials (RCTs), one non-RCT, and one retrospective cohort. Compared to sham, US-GONB significantly reduced pain intensity (MD: –3.57 points, 95% CI: [–3.95, –3.19]), monthly headache days (MD: –12.12 days, 95% CI: [–13.95, –10.29]), and analgesic use (MD: –2.05 analgesics, 95% CI: [–2.48, –1.62]). Efficacy relative to PRF was comparable; outcomes improved when PRF was added. SPG often showed superior results in head-to-head comparisons. Dizziness was the most frequent adverse event (38.9%), with serious complications being rare. US-GONB may be a well-tolerated, minimally invasive treatment for chronic migraine, particularly when pharmacologic strategies fail. It offers clinically meaningful improvements over sham but shows variable efficacy against active comparators. Some studies indicate potential synergistic effects with PRF. Limitations include small sample sizes and methodological heterogeneity, warranting larger standardized RCTs to inform clinical guidelines.