Traumatic facial nerve injuries: review of diagnosis and treatment.

Both blunt and penetrating craniofacial trauma may lead to severe facial nerve injury and sequelae of facial paralysis. Initial evaluation involves quantitation of motor deficits using a clinical grading system, such as the House-Brackmann scale. High resolution computed tomography is used for localization of nerve injury in suspected cases of temporal bone trauma. In the absence of gross radiographic abnormalities, electrophysiologic testing helps predict the likelihood of spontaneous recovery. In patients with deteriorating facial nerve injuries by electroneuronography, surgical exploration is the preferred management. Primary end-to-end neurorrhaphy is the preferred management for transection injuries, while facial nerve decompression may benefit other forms of high-grade nerve trauma. Secondary facial reanimation procedures, such as cranial nerve crossovers, dynamic muscle slings or various static procedures, are useful adjuncts when initial facial nerve repair is unsuccessful or impossible. A review of facial nerve trauma management and case illustrations are presented.