Drexel University researchers have found a new method for treating chronic wounds: an ultrasound applicator that can be worn like an adhesive bandage.

The device delivers low-frequency, low-intensity ultrasound directly to wounds, and was found to significantly accelerate healing in five patients with venous ulcers. 

These ulcers are caused when valves in the veins malfunction, causing blood to pool in the leg instead of returning to the heart. This pooling, called venous stasis, can cause proteins and cells in the vein to leak into the surrounding tissue leading to inflammation and formation of an ulcer. 

Venous ulcers account for 80% of all chronic wounds found on lower extremities and affect about a half million people each year. 

Annual treatment costs have been pegged at more than $1 billion. Passive treatments are most common, says Drexel’s Michael Weingarten, M.D. 

Results will be published in the Journal of the Acoustical Society of America.