One-Stage Reanimation of Paralyzed Lips Using Rectus Abdominis Muscle Neurovascular Free Flap

Park, Chong Soo; Ha, Bom Joon; Sung, Duk Hyun; Hyon, Won Sok; Kim, Jae Jung; Shin, Myoung Soo

Abstract

Facial paralysis is a devastating problem, since such a patient can neither make facial expressions nor enjoy an active social relationship. If it persists for a long time, facial muscles will have irreversible changes and deformities. The goal in the treatment of facial paralysis is to achieve a normal appearance at rest and reconstruct a natural, symmetrical smile. One of the most distressing figures in a facial palsy patient is oral deformity. There have been numerous corrective methods of reanimating the paralyzed lips. Recently the one-stage muscle transplantation, innervated by the contralateral facial nerve, has been introduced to solve this distressing problem. From March 1998 to December 1998, 3 patients(2 males and 1 female), who ranged in age from 17 to 33 years, underwent one-stage reanimation surgery of paralyzed lips using rectus abdominis muscle neurovascular free flap. All patients had unilateral facial paralysis caused by tumor resection. The rectus abdominis muscle with long intercostal nerve and pedicle vessels(deep inferior epigastric vessels) was elevated and transferred to the preoperatively designed subcutaneous pocket. The upper end of the muscle was fixed to the zygoma and parotid fascia, and the lower end was fixed to the mouth corner, upper and lower lip. The intercostal nerve was repaired to the non-paralyzed buccal branch of the facial nerve through the subcutaneous tunnel of the upper lip, and the vascular pedicle of the muscle flap was anastomosed to the paralyzed side of the facial vessels. The onset of muscle function was reported in all the patients. Five months after the surgery, nerve conduction study and EMG showed compound motor action potential(CMAP) and motor unit action potential(MUAP) of the transferred muscle respectively. Nine months after the surgery, we observed volitional muscle contraction. The power of contraction increased constantly for 2 years after the surgery.