[Experimental studies on tissue expansion in reconstructive surgery].

In the present study, a porcine model for controlled tissue expansion was investigated under the conditions or formation of extreme enlarged randomized flaps. The circulatory disturbances and necrotizing processes to be expected were evaluated immediately after flap formation by intravenous injection of fluorescein dye to predict the surviving area. Lectin histochemistry and immunohistology were performed using either the direct and indirect immunofluorescence technique (DIFT, IIFT) or immunoperoxidase techniques (POX). Over all, the expanded randomized flaps healed without complications in all animals. The acute randomized flaps showed clear necroses already after 10 days. In the thoracic area they averaged 60.3% (SD = 8.17%) and in the pelvic area 47.32% (SD = 14.11%) of the flap. The use of the fluorescein dye test in the present experiment demonstrated that the flap surviving area is significantly greater than the flap staining area. The regular expression of suprabasal keratins and epidermal lectin binding sites provides evidence for a normal epidermal cell differentiation.