A Scoping Review of Ultrasound Visualization of Thin Acupuncture Needles Inserted into the Human Body and Reporting of Imaging Conditions

Objective: This scoping review aimed to examine the existing literature on ultrasound visualization of acupuncture needles inserted into the human body, with a focus on image characteristics and methodological reproducibility. Methods: A search of the PubMed database was conducted on September 1, 2023, using terms related to acupuncture, dry needling, and ultrasound. English-language articles containing ultrasound images of acupuncture needle insertion into human tissue were eligible for inclusion. Results: In the 21 studies included in this review, acupuncture needles with diameters ranging from 0.16 to 0.35 mm were visualized using ultrasound imaging. However, the reporting of imaging conditions and equipment specifications was limited, leaving concerns regarding the reproducibility of methodologies and the validity of cross-study comparisons. Conclusion: Ultrasound visualization of acupuncture needles inserted into the human body has been demonstrated in several studies. To support further development in this field, future research should aim to provide standardized and detailed descriptions of imaging techniques and parameters.