Applying negative pressure to wounds may speed the formation of granulation tissue, decrease the amount of localized edema, increase blood flow, and accelerate healing. In the present study, we treated ten patients with stage IV chronic pressure ulcers using this negative pressure dressing technique. The long (A) and short (B) diameters of each ulcer were measured to determine size, and the vertical distance from the skin to the deepest point of the ulcer was measured to determine depth. Lesions were measured initially and at weekly intervals. The area of each lesion was taken to be 3.14 x A/2 x B/2 (cm(2)). When we compared the area of ulcer before and after the treatment, the area had been reduced in all cases, and the average reduction was 55.1%. The depth of ulcer also decreased in all cases, and the average reduction was 61.2%. Over the period of evaluation, the method was considered markedly effective in reducing the size and depth of ulcers.