Acupuncture for Tinnitus: A Scoping Review of Clinical Studies

Background: Acupuncture treatment for tinnitus has received attention owing to its potential as an alternative to conventional treatment modalities. We conducted a scoping review to identify detailed information on acupuncture treatment methods used in clinical studies and to provide useful information for practitioners, patients, and researchers. Methods: MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, Oriental Medicine Advanced Searching Integrated System (OASIS), Korean Research Information Sharing Service (RISS), DataBase Periodical Information Academic (DBPIA), and the China National Knowledge Infrastructure (CNKI) were searched from their inception to December 2023. This review included single-arm trials, open-label randomized controlled trials (RCTs), and double-blind RCTs using needle-type acupuncture to treat tinnitus in English, Chinese, and Korean. We investigated basic and detailed information on the acupuncture treatment methods, assessment methods, and study outcomes. Network analysis was also conducted to evaluate the centrality between acupoints in the doubleblind RCTs. Results: We included 106 articles. There were 11 single-arm trials, 90 open-label RCTs, and 5 double-blind RCTs. Most (89.6%) of these studies were conducted in China. Manual acupuncture was the most common type of acupuncture in treatment group. A total of 119 acupuncture points were used 1,138 times. The most frequently used acupoints were local points around the ear (TE17, GB2, SI19, and TE21). Both local and distant acupoints were used simultaneously in these studies. The treatment duration of 20-39 days, 10 to 19 sessions of treatment, the mean acupuncture duration of 30 min, needle diameter of 0.30 mm × 40 mm, and needling depth over 30 mm and less than 50 mm were confirmed as the most common. Conclusion: These study outcomes will enable future acupuncture studies on tinnitus to perform more effective and standardized acupuncture treatments in selecting acupoints and procedures. Furthermore, the study has implications for informing clinicians and students about more impactful acupuncture strategies for addressing tinnitus.