The lymphatic capillary network was visualized by fluorescence microlymphography (subepidermal injection of 0.01 ml of FITC-dextran 150000 under a fluorescence microscope) in the medial ankle region of 21 patients with chronic venous incompetence (CVI) and of 15 healthy controls. In severe CVI leading to trophical changes of the skin lymphatic microangiopathy was detected. Obliterations of parts of the superficial capillary network, phenomena of cutaneous reflux and increased permeability of capillary fragments occurred. These findings contrast to primary lymphedema where the rete remains intact in most cases.