Full-Thickness Skin Grafts in Reconstructive Dermatologic Surgery of Nasal Defects

The nose is one of the most important facial features and any change in its shape, colour or skin cover may be very obvious. Nasal defects are a common challenge for dermatologists and plastic surgeons in daily practice. Many benign and malignant lesions are located in the nasal region. Basal cell carcinoma is the most common skin cancer and is found frequently in this anatomical region. The size of defects secondary to excision of these lesions may not allow primary closure or reconstruction using skin flaps and requires the use of skin grafts. Skin grafts are particularly suitable for large defects occupying almost entire cosmetic units, and especially in elderly patients with acceptable cosmetic results in many cases. A precise knowledge of the anatomy of the nasal region is essential, before considering reconstructive options. Like the underlying bony-cartilaginous framework of the nose, the overlying skin may also be divided into vertical thirds. The skin of the upper third is fairly thick but tapers into a thinner mid-dorsal region. The inferior third regains the thickness of the upper third owing to the more sebaceous nature of the skin in the nasal tip. The dorsal skin is usually the thinnest of the 3 sections of the nose. The nasal muscles are deep in the skin and include four main groups: the elevators, depressants, compressor, and the dilators. The elevators are the procerus and levator muscle of upper lip and nasal ala. Depressants are composed of the nasal alar and nasal septum depressor. The muscles are interconnected by a fascia called the nasal superficial musculoaponeurotic system (SMAS). The soft outer tissue of the nose can be divided into subunits. The purpose of the subunits is to divide the nasal anatomy into segments useful for reconstruction. If more than 50% of a subunit is lost, it may be necessary to replace the entire unit with regional tissue or tissue from a donor. The subunits include the nasal dorsal segment, lateral wall segments, the hemi-lobe soft tissue triangle segment, and alar columellar segments. The nose, like the rest of the face, has a rich blood supply. The arterial supply to the nose can be divided principally into the internal carotid branches, ie branches of the anterior and posterior ethmoidal arteries of the ophthalmic artery and the external carotid branches,