Histological changes of the deepithelialized rat skin flap after subcutaneous transposition.
- Author:
Kun HWANG
1
;
In Sun PARK
Author Information
1. Department of Plastic Surgery, College of Medicine, Inha University, Inchon, Korea.
- Publication Type:Original Article
- Keywords:
Deepithelialized skin;
Transposed flap;
Vascularity;
Hair follicle;
Keratinization
- MeSH:
Abdominal Wall;
Animals;
Dilatation;
Epidermal Cyst;
Epidermis;
Fibrosis;
Hair Follicle;
Humans;
Lymphocytes;
Male;
Phenobarbital;
Rats*;
Rats, Sprague-Dawley;
Saccule and Utricle;
Scalp;
Sebaceous Glands;
Skin*;
Transplants
- From:Journal of the Korean Society of Plastic and Reconstructive Surgeons
1998;25(3):355-369
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Hair follicles become extinct in dermal graft within two months, when the direct vascular supply to the grafted flap is excluded. They cause a formation of microscopic epidermal cyst to be necrotic and replaced by fibrosis. In cases of preservation of normal vascular supply to the deepithelialized flap, however, the fate of skin appendages including hair follicles and sebaceous glands has not been reported. The present study was therefore designed to elucidate the histological changes of deepithelialized skin flaps which have been experimentally transposed under the subcutaneous layer of the normal skin. For that purpose, a rhombic area of 1.5 cm2was deepithelialized and transposed subcutaneously with the Limberg's flap design on the abdominal wall of male Sprague-Dawley rats. At the postoperative 3rd, 4th, 5th, 6th, 9th and 11th week, the tissues of the operated skin area were taken for histological and gross examination. Hair follicles and sebacrous glands of the transposed deepithelialized flap were biologically active and continued to grow during the experimental period, even though they were buried and separated from the outer circumastance by the overlying skin. However, continuous secretion of the sebaceous glands and its accumulation resulted in formation of a small sac-like pouch, a saccule, between the inner and outer root sheath of hair follicles in the transposed flap at three weeks after operation. Subsequent fusion of the saccules with neighbouring ones developed into a cyst, the luminal wall of which were covered by a epithelial lining derived from the outer root sheath of the hair follicles. At nine weeks after experiment, we observed that the epithelial lining of the cyst wall connected to that of epidermis of the overlying skin at the apical portion of the cyst. Moreover, it was observed that the distinct granulation and keratinization were seen in the epithelial lining of the cyst, representing a morphological similarity to epidermis at this stage. After nine weeks of experiment, we observed the inflammatory process showing a severe lymphocyte infiltration with vascular dilatation in some transposed skin flaps. Keratin immunoreactivity was significantly increased not only in the epithelial linings of saccules or cyst, but also in the epidermis of overlying skin in proportion to the period of time of experiment. It suggests that skin appendages including saccule and cyst of the transposed flap may maintain normal bioactivity during the experiment. Based on the above results, we recommend that the hair follicles should be completely removed by careful resection at the subfollicular in case of deepithelialized skin flap, especially in the area of scalp.
