Visualising vascular perfusion in isolated human abdominal flaps using dynamic infrared thermography (DIRT) and indocyanine green fluorescence video angiography (ICG-FA)

Abstract

This experimental study compared the direct technique indocyanine green fluorescence angiography (ICG-FA) and the indirect technique dynamic infrared thermography (DIRT) for visualising skin perfusion. Eight isolated human transverse abdominal skin flaps, obtained from female patients undergoing abdominoplasty, were used. A total of 19 selected vessels were individually perfused. Warm and cold perfusate was used for visualising skin perfusion with DIRT. Both techniques were tested for repeatability, making up a total of 34 perfusions. Qualitative analysis of the rate and pattern of perfusion visualised by both techniques was carried out. The extent of the perfused area indicated by the indirect DIRT technique corresponded well with the perfused area indicated by the direct ICG-FA technique. The appearance of distinct hot spots in the IR images provided additional information on the distribution of perforating vessels. It is concluded that in experimental situations the non-invasive DIRT technique is a good alternative to the invasive ICG-FA technique for visualising skin perfusion.