A Clinical Therapeutic Assessment for the Administration of Different Modes of Ultrasounds to Stimulate the Zusanli Acupuncture Point of Hypertension Patients

A clinical trial to assess the therapeutic effect of ultrasonic stimulations on the acupuncture point was carried out. Specifically, ultrasound frequencies of 1 and 3 MHz associated with different duty cycles of the tone burst wave at different acoustic power were employed to stimulate the Zusanli acupuncture point of a subject's right leg. The Ryodoraku values were measured from the 12 primary meridians of both hands to monitor the change of the meridian impedance following the stimulation. Totally 67 healthy volunteers and 60 hypertension patients were evaluated, in which these subjects were administered ultrasonic stimulations for 10 minutes. In addition to measurement of the Ryodoraku value, physiological quantities including blood pressure and pulse rate were also recorded. Results demonstrated that after ultrasound stimulations on the Zusanli acupoint, the Ryodoraku values measured from both the hypertension patients and healthy subjects were significantly decreased (p<0.01). The percentage change of the Ryodoraku value associated with stimulations using a 3 MHz is 8% larger than that of a 1 MHz. The application of a 770 mW ultrasound has an approximately 6% percentage change larger than that of a 380 mW. Moreover, ultrasonic stimulation of a 100% duty cycle developed an approximately 7% percentage change more than that of a 10% duty cycle. In additional, the systolic pressure, diastolic pressure, and pulse of hypertension patients were obviously reduced (p<0.05) after the ultrasonic stimulation. The average decrease of these physiological quantities was from 3 to 7%. Therefore, this study verified that the therapeutic effect of ultrasonic stimulations on the acupuncture point, which could be taking into account for further development of an ultrasonic acupuncture system.