Regeneration of subcutaneous connective tissue in children. A histological study with application of the CELLSTIC device.

Cellular patterns of healing subcutaneous connective tissue were studied histologically in 22 pediatric surgical patients using the CELLSTIC device. This wound drain, specially developed for this purpose, consists of a standardized, viscose cellulose sponge inside a thin silicone rubber tube. When left between the wound edges, wound exudate flows through the drain, allowing its cells to attach themselves to the sponge surface. The sponge serves as a framework within which the cells may migrate, divide and transform. During the first 12 h the cellular pattern in the sponge resembles that of peripheral blood, whereafter the number of polymorphonuclear leukocytes, almost exclusively neutrophils, gradually increases. Later on, monocytes, macrophages and lymphocytes invade. Fibroblasts were usually seen at the end of the third day postoperatively, but in some cases the first fibroblasts appeared even earlier. CELLSTIC neither disturbs normal wound healing nor increases the rate of wound infections. CELLSTIC, as a cell culture in situ, provides a practical way to study human connective tissue regeneration under both physiological and pathological conditions.