Objective To discuss the individualized operation standard and its safety on the deep acupuncture at Tianshu （天枢 ST 25）. Methods Acupuncture was applied to Tianshu （天枢 ST 25）） in 39 patients. The individualized standard depth of insertion at the acupoint was determined as the penetrating the peritoneum with needle by 1 to 2 mm. The regression analysis was adopted to analyze the impacts of abdominal circumference （AC, cm） on the peritoneal position via CT cross-section scanning and image survey. Results The formula of rational needling depth at Tianshu （天枢 ST 25） with individualized deep acupuncture was： depth=-0.562＋0.045. AC. Conclusion The depth of insertion at Tianshu （天枢 ST 25）, determined as penetrating the peritoneum with needle by 1 to 2 mm is safe and feasible, which may be applicable and have the guidance significance for the assessment of clinical operation and safety on the deep acupuncture at the other acupoints on the abdominal region.
