MORPHOLOGY OF LYMPHATICS IN HUMAN VENOUS CRURAL ULCERS WITH LIPODERMATOSCLEROSIS

Abstract

A morphological evaluation of lymphatic vessels of skin leg ulcers was performed in 39human subjects with longstanding venous insufficiency and lipodermatosclerosis. Light andelectron microscopy demonstrated that the superficial fibrin and inflammatory cell layers andintermediate blood capillary layer of the ulcer bed, which were primarily granulation tissue, didnot contain lymphatics. Moreover, lymphatic capillaries were present only sporadically in thetransition zone from granulation tissue to the deeper collagenous scar layer of the ulcer. In someinstances, in the deepest part of the ulcer bed near the crural fascia, there were one or twothicker lymphatic collectors with valves, which were continuations of collectors from the plantarfoot region. Lymphatics were present at the border of the ulcer and in lipodermatosclerotic skin,but the endothelium and muscle lining layer were partially destroyed. Lymphatic capillaries werecharacterized by open interendothelial junctions in conjunction with subendothelial edema. Inlipodermatosclerotic skin, the morphologic changes suggest that absorption of interstitial fluidand lymph is markedly disturbed adjacent to the ulcer bed, which likely contributes to both slowhealing and high recurrence of skin ulcers associated with longstanding venous insufficiency