Microcirculation in mixed arterial/venous ulcers and the surrounding skin: clinical study using a laser Doppler perfusion imager and capillary microscopy.

To treat mixed skin ulcers effectively, it is important to investigate skin microcirculation in greater detail. Therefore, we used laser Doppler perfusion imaging and capillary microscopy for assessing both subpapillary and nutritive microcirculation in four defined regions of the skin in 17 patients with mixed ulcers caused by a combination of peripheral arterial occlusive disease and chronic venous insufficiency. Laser Doppler area flux was significantly higher in the ulcer areas than in the areas without granulation tissue and those in intact skin. The flux in the scars was higher than that in the intact skin or in the ulcer areas without granulation tissue. Capillary density in the intact skin was higher than the densities in nongranulation tissue areas, granulation areas, and scar areas (p<0.001 for all comparisons). To conclude, the ulcer areas without granulation tissue did not show a healing tendency due to poor subpapillary and nutritive perfusion; the granulation tissue exhibited high subpapillary perfusion as a sign of healing. In the scars, sufficient blood supply could be detected in both layers as a sign of an almost complete healing process. Blood supply in the intact skin is, however, already affected by distorted microcirculation in the ulcers.