Low-frequency ultrasound treatment of chronic venous leg ulcers in an outpatient therapy

Low-dose ultrasound seems to be an effective method to enhance wound healing, particularly in chronic venous leg ulcers. The aim of our investigation was to examine the effect of 30 kHz low-dose ultrasound in local treatment of chronic venous leg ulcers, when added to conventional therapy of outpatients. Twenty-four patients with chronic ulcerations of the leg due to chronic venous insufficiency were randomised in placebo-controlled parallel groups in a single-blind clinical study. Patients were randomised to conventional therapy with topical application of hydrocolloid dressings and compression therapy or conventional therapy with additional ultrasound treatment for 12 weeks. The ultrasound treatment consisted of 10 min of footbathing, with application of 30 kHz continuous ultrasound 100 mW/cm2 three times a week. The ulcer area was measured by planimetry, using a millimeter grid before treatment and after 2, 4, 6, 8, 10 and 12 weeks of therapy. The ulcer radius and the daily ulcer radius reduction were calculated. Colour photographs of the ulcers were taken under standard conditions at the same time. After each treatment local findings and side effects were recorded. After 12 weeks of treatment the control group showed a mean decrease of 16.5% in the ulcerated area. In contrast the mean ulcerated area decreased by 55.4% in the ultrasound group (p<0.007). The daily ulcer reduction in the ultrasound-treated patients was 0.08 mm+/-0.04 mm and in the placebo patients 0.03 mm+/-0.03 mm. Patients recorded only minor side-effects such as a tingling feeling and occasionally pinhead-sized bleeding in the ulcer area. The application of low-frequency and low-dose ultrasound is a helpful treatment option in chronic venous leg ulcers, especially if they do not respond to conventional ulcer treatment.