Background

Whereas the entity of facial paralysis was described and linked to damage of the facial nerve almost two centuries ago, efforts to perform corrective procedures evolved very slowly. Until 30 years ago, the problem was thought of by most as a permanent deformity. However, increasing interest in correction of the problem was generated during the 1960s. Electrophysiologic techniques for measurement of neural function, classification schemes for the measurement of recovery, and surgical techniques for correction were developed.

In this contemporary era, the first-line approach to reanimation of the atrophic paralyzed face has been to perform a regional muscle transfer to provide dynamic facial movement.2'3 Both masseter and temporalis muscles have been used; currently, the temporalis muscle is favored. The middle third of the muscle is brought down to the oral commissure, and the donor site defect filled with an ipsilateral temporoparietal fascia flap (TPFF).4 An accompanying eye procedure, such as gold weight implantation, is usually executed for eyelid closure.

Drawbacks to the temporalis muscle transfer include a persistent soft tissue defect in the donor site despite partial fill-in with the TPFF and the fact that the resulting oral commisure movement is not physiologic. Physical therapy helps train individuals to elicit a smile by biting down; however, emotive expression is never restored.

Techniques for the transfer of free muscle grafts for dynamic facial reanimation have also been developed over the past two decades.5 Gracilis, pectoralis minor, latissimus dorsi, and serratus anterior muscle slips have all been used. Microneu-rovascular transfer is carried out in conjunction with a cross-facial jump graft for innervation. Results from these free muscle transfers vary substantially. Drawbacks include nasolabial distortion, excessive cheek fullness, and flap failure. For these reasons, they tend to be reserved for congenital facial palsy patients (i.e., Mobius syndrome).

Static reanimation techniques have traditionally been employed in clinical situations in which more lengthy muscle transfer techniques are not a viable option. This would include the management of patients in whom the longer anesthesia time presents too high an operative risk or in patients whose overall prognosis is poor. It is recognized that the goals of surgery do not include dynamic function of the afflicted side. The procedures simply help restore symmetry at rest and improve functional oral competence.

The restoration of resting facial symmetry can be achieved with a wide variety of surgical techniques, depending on the anatomy of the individual and the precise functional deficits. Among the most common static procedures are superficial musculoaponeurotic system (SMAS) plication, brow-lifting procedures, and oral commissure Z-plasties designed to ameliorate speech slurring and drooling.1 Additional procedures, including judicious lower lip resections and nasolabial fold resections, have been designed to achieve more precise facial symmetry. The nasal valve collapse that sometimes accompanies facial paralysis can be managed with standard nasal valve widening procedures, and the paralyzed eye can be managed with tarsorrhaphy, medial canthoplasty, and/or spring or gold weight implantation.

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