Study of temporal and perfusion physiology of skin capillaries in the dorsum of the foot

The aim of this study was twofold: firstly, to study the nature of any temp oral variation in capillary numbers, and secondly to determine the proporti on of perfused to total nutritional capillaries in normal skin. Using in vi vo microscopy, the temporal behaviour of the number of visible capillaries in the skin of the dorsum of foot was observed over periods of time varying from 5 min to 55 days in 15 healthy subjects. Capillary perfusion was then studied by comparing capillary numbers before and after intravenous inject ion of sodium fluorescein. The mean percent difference in the number of vis ible capillaries over a mean period of 25.3 days was 5.5%. The percentage r atio of perfused to total capillaries was 54.2%. This study shows that ther e is little quantitative change in capillary numbers over periods of up to 50 days, and that under physiological conditions, about half of the nutriti onal capillaries of skin are not perfused. Copyright (C) 2001 S. Karger AG, Basel.