PLASTIC SURGERY

surgical specialty concerned with the correction of disfigurement, restoration of impaired function, and improvement of physical appearance. It is largely concerned with the bodily surface and with reconstructive work of the face and exposed parts. Although surgical reconstruction of the nose was performed by Hindu physicians before the time of Christ, modern techniques of plastic surgery were originated in the post-World War I years by surgeons repairing the wounds and disfigurements of combat veterans. The term plastic refers to the molding and reshaping of body tissuesbone, fat, muscle, cartilage, and skin. Tissue may be moved to fill a depression, to cover a wound, or to improve appearance. The transfer of skin tissue (skin grafting) is one of the most common procedures performed in plastic surgery. Skin grafts may be taken from the recipient (autografts), from a donor of the same species (allografts), or from a donor of a different species (xenografts). Sheets of epithelial cells cultured in vitro and synthetic compounds such as silicone are also used as a substitute for absent or deficient natural tissue. Tissue may be completely removed to alter the contours of a feature, as in rhinoplasty (reconstruction of the nose), otoplasty (ear reduction), and blepharoplasty (the removal of skin and fatty tissue from the eyelids), or to restore youthful appearance, as in rhytidectomy (face-lift, in which excess skin is removed from the face and neck). Plastic surgery is sometimes considered, incorrectly, to be synonymous with aesthetic, or cosmetic, surgerythat is, surgery performed solely to improve appearance in otherwise healthy persons. Into this classification fall the majority of cases of rhinoplasty, rhytidectomy, breast augmentation, hair transplantation, and other procedures. The aesthetic element of most plastic surgery, however, is directed at improving physical appearance after disfigurement caused by burns, removal of tumours, and reconstructive work. The correction of a perceived physical imperfection for its own sake, while valuable for the psychological benefits it imparts to an individual, is not the main focus of most plastic surgery. The essence of technical plastic surgery lies in the careful planning of incisions so that they fall in the line of natural skin folds or lines and in the appropriate choice of wound closure, emphasizing the use of fine suture material and the early removal of exposed sutures so that the wound is held closed by buried sutures. Among the techniques used in plastic surgery are incision, excision, chemosurgery, electrosurgery, laser surgery, dermabrasion, and liposuction. Reconstructive plastic surgery is performed to correct severe functional impairments caused by burns and other traumatic injuries; to correct acquired or congenital abnormalities, such as cleft lip and cleft palate, facial bone fractures, and tumours; and to compensate for tissue removed in cancer or other surgery, including reconstruction of the breast following mastectomy. The development of microsurgery in the 1960s and '70s greatly expanded the scope of reconstructive surgery, allowing surgeons to reattach severed fingers and limbs. Exceedingly fine needles and sutures make it possible for the surgeon to rejoin small blood vessels and other minute structures under an operating microscope. Combinations of bone, muscle, and skin tissue, known as free flaps, that previously had to be shifted gradually from remote sites can now be transplanted in a single procedure, greatly increasing the number of defects that can be corrected. The size and thickness of such flaps and the placement of their attendant structures and vessels can even be customized to fit the requirements of the recipient site. Magnetic resonance imaging, computed tomography, and other computerized imaging techniques have also revolutionized the field, vastly improving surgeons' abilities to analyze deformities and to plan and visualize complex reconstructions.