SKIN, DISEASES OF. Treated under individual headings: ACNE, ECZEMA, etc.
are obtained from the patient himself, they are called autografts; when from another person, heterografts; and when from animals, zoografts. The best re sults are derived from autografts. Het erografts grow better than zoografts, but it must not be forgotten that they may cause disease, especially syphilis.
The Method of fresh wounds or healthy granulating surfaces little preparation is necessary. Ulcers should be clean and devoid of necrotic tissue; a good indication of fitness is the appearance of a pedidle of new skin around the edges. Desirable as asepsis undoubtedly is, in the majority of in stances it cannot be obtained. It is suf ficient that suppuration is not too pro fuse and infection not too virulent. If the circulation is impaired by surround ing cicatricial tissue or by varicosities, or if marked inflammatory changes are present, these conditions must be modi fied by incisions, moist compresses, rest in bed, etc. Pale, indolent, or exuberant granulations should be treated by cau terization, compression, etc. If strong antiseptics have been employed, they must be washed away before transplan tation is begun.
The grafts, which are best obtained from the arm or thigh, should be about the size of a grain of wheat. They are cut by elevating a portion of skin with mouse-toothed forceps and dividing it with scissors curved on the flat, removing the entire epithelium and a portion of the corium without disturbing the sub cutaneous fat.
The bits of cuticle adhere to the sur- I face to be grafted, especially if gentle pressure with a pledget of gauze be em ployed. Nothing is gained by scraping or in any way wounding the granulations. The transplantations should be close to gether, as the greatest size to which a graft can grow is perhaps that of a silver dime.
Immediately over the grafts may be placed strips of rubber protective; or, better, a single layer of gauze, which may be pinned around a limb or fastened at the edges with collodion. The latter method is simpler and permits freer exit of secretions.
Whether the external dressing is moist or dry is usually of little importance, but no powerful antiseptic should be used. As there is generally some suppuration, it is necessary to change the superficial portion of the dressing every twenty four hours at least, leaving in place the rubber tissue, or the undermost layer of gauze, as the case may be. Gentle irri
gation with a solution of salt or boric .acid assists in maintaining cleanliness.
The Method of Thiersch.—There is no process of skin-grafting so simple, so re liable, and so generally applicable as this. Granulating surfaces or fresh wounds may be covered with epithelium in from ten days to three weeks; cicatricial con tractions are avoided; and in many cases the cosmetic value can scarcely be over estimated. The process is of great value in the treatment of ulcers, burns, and defects following operations or injuries. The grafts will adhere to periosteum; to bone from which the external surface has been removed; to tendons, fascia, Jura mater, muscle, etc.
The patient is anesthetized, and if granulations are present it is best to scrape them away with a sharp spoon down to the comparatively firm tissue beneath, although this is not absolutely necessary. Oozing is checked by eleva tion and pressure, an Esmarch bandage being unnecessary. The grafts are cut with a razor from the anterior surface •of the thigh. An assistant makes the skin tense by means of a hand on either side of the limb, while the operator, standing with his back toward the pa tient's feet, cuts toward himself, with his left hand stretching the tissues in the direction of the knee. With a backward and forward sawing motion it is not diffi cult to obtain shavings of epidermis an inch or more wide and several inches in length and as thin as paper, which is a desirable thickness. No appreciable scar results. The delicate strips fold up on the blade of the razor from which they may be spread directly upon the surface to be grafted, and so adjusted that they overlap each other and the edges of the skin, completely concealing the raw sur face. Healing without suppuration is not uncommon. Next to the trans planted cuticle are placed strips of rub ber tissue or a single layer of gauze, as described in the Reverdin method. If a moist dressing is employed, it should consist of a thick pad of gauze saturated with normal salt solution and covered with cotton and oiled silk. This should be removed often enough to keep it moist. A dry dressing answers equally well, applied as in the treatment of ordi nary wounds.