Fluorescence microlymphography.

Abstract

SUMMARY Microneedles, 0.2 mm o.d., were connected to a microsyringe and mounted on a micromanipulator. Under microscopic control, 0.01 ml of a 25% solution of FITC-labeled dextran-40 or dextran-150 were injected into the subepidermis at the big toe near the nailfold or in the medial ankle region. Fluorescence intravital microscopy revealed a network of lymphatic microvessels. The comparison with recent anatomic studies reveals that the reticular network visualized by FITC-dextran corresponds to the network in the stratum papillare. In 20 healthy subjects lymphatic capillaries were detected in a restricted area on the lateral aspect of the big toe. In 10 patients with primary lymphedema, the dye expanded to almost the entire dorsal skin surface of the big toe. In two cases, enlarged and tortuous microvessels of pathologic shape were observed.Fluorescence microlymphography is a simple and nearly atraumatic approach for depicting the intravital anatomy of human skin lymphatic capillaries.

Clinical and diagnostic aspects of lymphedema

“…It is an almost atraumatic technique as described by Bollinger et al [26]. FITC-dextran (fl uorescein isothiocyanate-labeled dextran) has a molecular weight of 150,000 Dalton and is available as a powder.…”

“…In most studies the patients rested comfortably in supine position. Microinjections in big toes [26], in the volar part of the forearm, and in the face were performed [28]. It can even be applied in regions with indurated skin or near venous ulcers.…”

Microcirculation: its significance in clinical and molecular medicine

“…The subcutaneous microinjection of fluorescein isothiocyanate (FITC) dextran (150,000 molecular weight) renders visible the lymphatic capillary network of the skin, a circulatory system of difficult access [8,9].…”

“…Fluorescence microlymphography is clinically useful in patients with lymphoedema [3,74] (Fig. 5), and has demonstrated hypertension, a recently recognized pathophysiological phenomenon.…”

“…5), and has demonstrated hypertension, a recently recognized pathophysiological phenomenon. Fluorescence capillaroscopy can also be of clinical value in these patients [3,74].…”