['To evaluate the immediate effects of indirect moxibustion, a traditional local thermal therapy, on renal hemodynamics by using Doppler ultrasonography (US).', 'Prospective observational study of postintervention changes in several variables.', 'Gifu University Hospital, Gifu, Japan.', 'Eleven healthy persons (7 men and 4 women; mean age±standard deviation, 32.6±5.7 years) were enrolled.', 'Indirect moxibustion was applied for 4 minutes to bilateral lower back acupuncture points (BL23). Each participant received 3 successive treatments.', 'The main outcome measurement was resistive index (RI) in the renal segmental arteries. Blood flow variables, including RI, were measured for 6 renal segmental arteries by Doppler US at rest (baseline), immediately after completion of moxibustion (post 1), and 10 minutes later (post 2). Participants were monitored for adverse events during the intervention.', 'The mean RI was 0.578±0.037 at baseline, 0.546±0.027 at post 1, and 0.547±0.032 at post 2. RI decreased significantly between post 1 and baseline (95% confidence interval [CI], -0.053 to -0.011; p=0.003) and between post 2 and baseline (95% CI, -0.052 to -0.009; p=0.005). No adverse events, such as burns, were observed.'] Does traditional thermal therapy with indirect moxibustion decrease renal arterial resistive index?