Island Forehead Skin Flap
R. V. ARGAMASO
This is an excellent flap for reconstruction of defects of the nose, which may require sacrifice of some normal skin, but the end result is likely to be superior. The skin island in the forehead should be outlined as high as possible to facilitate its transfer to the most caudad portion of the nose.
The superiority of forehead skin for nasal reconstruction is unquestioned. For a full-thickness skin replacement of a sizable defect at the distal part of the nose, the island skin flap deserves practical consideration (1).
Distally, the skin of the nose is thick and contains numerous sebaceous glands. It drapes over the alar and upper lateral cartilages that support the lobule and give definition to the nasal tip. Full-thickness skin loss through trauma or disease results in a diminution of tip projection. Cicatricial contractures and secondary deformities from skin-graft replacement with poor color match and thickness can become sources of great embarrassment.
A convenient pedicle for a forehead flap is supplied by the orbital branches of the ophthalmic artery. The supraorbital artery is a branch of the ophthalmic vessel as it crosses over the optic nerve. It exits with the supraorbital nerve through the supraorbital foramen and divides into superficial and deep branches. The supratrochlear artery, a terminal branch of the ophthalmic artery, leaves the orbit at its medial angle and ascends to the forehead near the midline.
These vessels anastomose freely with each other, with the frontal branch of the superficial temporal artery, and with vessels from the opposite side of the forehead. This rich network of anastomoses ensures an adequate circulation to a large skin island through a relatively narrow subcutaneous pedicle supplied by either one of these orbital arteries.
FLAP DESIGN AND DIMENSIONS
The vertical dimension of the donor area of the forehead should be of sufficient length to provide a flap for easy transposition and reach to the nasal tip. An outline of the nasal defect is drawn on paper and transposed downside-up to the forehead donor area. The size of the outline transferred to the skin is slightly exaggerated to increase the area, allowing for tissue shrinkage. Hair follicles are avoided.