Measurement of the lymphatic clearance of the human skin using a fluorescent tracer

The lymphatic clearance of the human skin at the instep of the foot was mea sured in 20 healthy volunteers (mean age +/- SD 33.8 +/- 10.5 years). Ten m icroliters of fluorescein isothiocyanate-dextran 150,000 were injected intr adermally and the fluorescent light intensity of the deposit was measured 1 0 min and 24 h after injection by window densitometry. Fluorescent light in tensity decreased by 31.2 +/- 13.5 arbitrary units (p < 0.0001) or by a fac tor of 4.1 +/- 3.9. Reproducibility was tested 2-6 weeks later in 7 subject s and an intraclass reliability of 0.76 was found. These are the first meas urements of the lymphatic clearance of the human skin using a fluorescent t racer. The method is easier and safer than the isotope clearance technique and small areas of the human skin can be investigated. The data found form a basis with which to compare measurements made in patients with different forms of edema. Copyright (C) 2001 S. Karger AG, Basel.