Morphological changes of dermal blood and lymphatic vessels in chronic venous insufficiency of the leg.

Morphological changes of dermal blood and lymphatic microcirculation in skin biopsies from patients affected by Chronic Venous Insufficiency (CVI) associated with stasis dermatitis of the lower limbs, are reported here. Blood vessels are characterized by an occluded lumen, thickening and reduplication of the basement membrane. The structural changes in dermal lymphatic vessels are: (i) collapsed lumen of lymphatics located in the papillar dermis; (ii) numerous and complex interdigitations between contiguous endothelial cells and lack of open junctions; (iii) derangement of the anchoring filaments that normally pull the lymphatic lumen open. The connective matrix is characterized by fibrosis with formation of dense bundles of collagen and elastic fibers. These results suggest that the dermal lymphatic and blood microcirculation in CVI are connected to a reduced fluid exchange capacity because of the structural changes occurred in the vascular and lymphatic wall and in the surrounding connective tissue.