From 1840 to World War I, it became apparent that results of reconstructions using unlined flaps were poor. The external shape of the nose and its airways became distorted by the contracting scar on the underlying raw surface of the covering flap. Surgeons realized that they must provide lining. Ideally, missing tissue should be replaced in kind and quantity but residual intranasal mucous membrane seemed inadequate. Carpue, Von Dreafe, Delbech, Labat, Blandin, and Dieffenbach folded the distal end of the forehead to form a columella but left the alar portions unlined. The nostril openings simply were stented with rubber tubing.
In approximately 1842, Petrelli emphasized using the forehead to line itself. His solution was to line the covering flap by folding and twisting it onto itself, thus creating its own inside and outside. This formed, in a manner of speaking, a tip, ala, and columella, while eliminating raw surfaces on the lower part of the reconstructed nose. Of course, this created a huge forehead defect and, unless the hairline was high, moved hair-bearing scalp onto the nose. One can surmise that surgeons then first exclaimed, "Midline tissues in the forehead are inadequate in length and width to permit satisfactory nasal reconstruction without excessive donor deformity!" To this day, many surgeons incorrectly feel that an area of skin of at least 7.5 X 7.5 cm is required to reconstruct a major nasal defect, seeming to preclude the use of midline forehead tissues.
Normal hairline position limited the flap length available for folding unless hair was to be transferred to the nose. The problem seemed insurmountable. First, the 180° twist of the Indian pedicle and the location of its base at or above the eyebrows created a high arc of rotation. Too often, the flap did not reach the columella. Second, at least one third of the flap was used for lining and cover. Midline forehead tissue seemed unable to provide enough tissue to create a long columella that at the same time could maintain projection, allow infolding of the covering flap for lining, and avoid unnecessary tension that might diminish flap vascularity. Thus, in 1850, Auvert designed a longer flap by slanting it across the forehead at an angle of 45°. These "oblique" flaps came into general use in the latter part of the 19th century and were designed to follow the hairline into the temple recess.
German surgeons of the same period positioned forehead flaps horizontally. Their wide base included blood supply from the supraorbital vessels on one side. Gillies used such flaps during World War I but in 1935 he described a radical departure from the oblique forehead flap. His up-and-down flap ascended over one supraorbital pedicle, onto the hair-bearing scalp, and then descended back into the forehead. This provided greater flap length and was sufficiently wide to ensure the blood supply.
In 1942, Converse modified the up-and-down flap by creating a long pedicle that was camouflaged within hair-bearing skin and included the major vascular supply to the scalp. Converse felt its advantages were an ability to transfer larger amounts of forehead tissue and the location of a permanent skin-grafted donor site over the lateral aspect of the forehead where it was supposed to be less conspicuous. Unfortunately, the irregular pigmentation and texture of a skin graft stands out as a patch regardless of position. In addition, the scalping flap is an operation of greater magnitude than the median forehead flap and leaves a large donor area that must be left open temporarily or skin grafted. It produces a hairy pedicle that hangs, sutured to the recipient site and stretched across the orbital region, obstructing vision during transfer.
All these flaps were designed solely to provide additional length, and each produced a forehead defect that was harder to close. Surgeons were caught in a difficult predicament, worrying about both facial scarring and bemoaning the insufficient tissue available to make a nose. They took more and more forehead skin for reconstruction, enlarging the forehead defect. Obviously, when forehead skin is used for lining as well as cover, the burden imposed on the forehead is increased and even greater donor deformity is created. Adding insult to injury, surgeons often used forehead skin for nasal reconstruction and for adjacent defects. Neighboring cheek, lip, and nose losses in the mid face were filled with one even larger flap. Frequently, a single plump lump replaced the 3-dimensional contours of these multiple contiguous facial units, and the forehead was scarred beyond repair.
During the same period, it became clear that without a skeletal framework, the soft tissue of cover and lining collapsed in major reconstructions, impairing the airway and limiting projection. A rigid skeleton was needed to provide support, projection, and contour but these folded flaps were thick and often ischemic. Because of their bulk and the risk of extrusion, cartilage grafts were not used primarily but were added months later in final touch-up operations. Only after soft tissues had healed could large bone-and-cartilage pieces be placed as cantilever grafts to lift the dorsum and tip. Unfortunately, once gravity and the contractual effects of the healing process had destroyed nasal contour, it rarely could be regained. Covering skin became constricted and stiff. Multiple late revisions were required to sculpt subcutaneous tissue into a semblance of nasal shape.
The infolding of forehead flaps for lining wasted forehead skin and precluded the accurate placement of primary columellar, alar, and tip support. A single covering flap cannot be folded into the 3-dimensional shape of the normal nose. The alar rims and tip only can become thick and, without support, shapeless.
Despite its limitations, the folding of covering skin for lining, and specifically the scalping flap, came to be the most commonly used method of nasal reconstruction. The median forehead flap was recommended only to replace small nasal losses, unless the patient was bald or had an unusually high hairline that allowed a longer vertical flap.
In reality, recreating the nose is impossible. What nature has fabricated in a mother's womb is not reproducible. Thus, the reconstructive surgeon's task only can be to fashion bits and pieces of expendable tissue into a facsimile of cover, lining, and support, to give the visual impression of a normal nose. The quandary remains - how to provide enough tissue to reconstruct the nose without excessive forehead scarring? The riddle of plastic surgery is to find and fit the piece that best solves the puzzle. The solution is a happy, normal-looking patient.
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