Microangiopathy of the skin and the effect of leg compression in patients with chronic venous insufficiency

Purpose: The reasons for the efficacy of leg compression in the treatment of chronic venous insufficiency are not clear. We have used laser Doppler fluxmetry to assess the effect of external compression on the skin microcirculation. Methods: Fifteen patients with lipodermatosclerosis caused by chronic venous insufficiency and 15 control subjects were studied in the supine and sitting positions. The laser Doppler probe, incorporated in a polyethylene chamber, was applied to the lower leg underneath a blood pressure cuff. Pressures were applied from 10 to 100 mm Hg in increments of 10 mm Hg. A computer data logging system recorded laser Doppler flux blood cell velocity, and concentration of moving blood cells. Results: In patients in the supine position, 20 mm Hg compression resulted in a median increase of 33% in laser Doppler flux, and a median increase of 79% in blood cell velocity, but higher pressures caused a progressive decrease in laser Doppler flux and blood cell velocity. With the patient in the sitting position, compression up to 60 mm Hg caused an increase in laser Doppler flux (median percentage increase at 20 mm Hg compression 84%) and blood cell velocity (median percentage increase at 20 mm Hg compression 22%). At 20 mm Hg compression, the concentration of moving blood cells decreased in the supine position (median percentage fall 27%) but did not change significantly in the dependent position. The effects of compression in control subjects were similar to those in patients, but to a lesser degree. Conclusion: Our study suggests that compression treatment may achieve part of its effect by causing an increase in the microcirculatory flow velocity. (J V ASC S URG 1994;19:1074–83.)