xRead - Facial Reconstruction Following Mohs Micrographic Surgery

Larrabee & Moyer

428

by the philtral groove. The upper lip consists of a medial and 2 lateral subunits, demarcated by the philtral ridges and the nasolabial folds ( Fig. 2 ). Each lip is composed of the orbicularis oris mus cle that is invested by skin and subcutaneous tis sue externally, by mucosa and submucosa intraorally, and the vermilion over its free edge. The lips contain a circular muscular structure, the orbicularis oris, that is pulled into an oval by radi ally oriented cheek suspensory muscles ( Fig. 3 ). 4 All of these muscles are innervated by the facial nerve. The second division of the trigeminal nerve via the infraorbital nerve provides sensory innerva tion to the upper lip, and the third division of the tri geminal nerve via the inferior alveolar nerve provides sensory innervation to the lower lip and chin. The arterial supply of the lips is the labial ar tery, which is a branch of the facial artery. Veins follow the arteries. Functional considerations for repair include maintenance of oral competence for facilitation of oral intake, containing secretions, articulation, kissing, smiling, and expressing emotion. The lips are essential for phonation of the letters M, B, and P. Aesthetic considerations include sym metry, normal anatomic proportions, presence of a philtrum, normal oral commissures, and the presence of a vermilion-cutaneous white border. Other considerations are the age, general state of health of patients, previous treatment, tissue laxity, and dental status. 1 The preferred method for reconstruction of most cutaneous tumors of the lip is fusiform excision and primary wound repair. Small defects of the cutaneous lip can be closed with elliptical excision with primary closure. The fusiform excision should be oriented with its long axis parallel to the relaxed skin tension lines if possible ( Fig. 4 ). M-plasty can aid in closure that does not cross aesthetic bor ders of the lips or into the vermilion. PRIMARY REPAIR

Fig. 1. Aesthetic units of the face. ( From Bradley DT, Murakami CS. Reconstruction of the cheek. In: Baker SR, editor. Local flaps in facial reconstruction. 2nd edition. St Louis (MO): Mosby; 2007. p. 526; with permission.)

labiomental crease inferiorly, and the nasolabial folds laterally. The lower lip acts as a dynamic dam to retain saliva and prevent drooling. 4 The lips are defined by the red-white vermilion-cuta neous border. The white roll separates the skin and vermilion, whereas the red line separates the dry vermilion from the wet vermilion or intraoral labial mucosa. Cupid’s bow is composed of the apices of the upper lip and central depression and is of variable prominence. The medial upper lip vermillion prominence is the tubercle. The phil tral columns extend up to the columella, separated

Fig. 2. Surface anatomy of the lip. ( From McCarn KE, Park SS. Lip reconstruction. Facial Plast Surg Clin North Am 2005;13:302; with permission.)