Facial reanimation according to the postresection defect during lateral skull base surgery

The vast majority of benign tumors of the cerebellopontine angle, temporal bone, and parotid gland can be successfully resected without permanent injury to the facial nerve. Malignant tumors or recurrent disease may require facial nerve sacrifice, especially if preoperative facial paresis is present. This article will present case examples of the various methods to reconstruct facial animation after lateral skull base resections that require sacrifice of cranial nerve VII, and the associated mimetic facial musculature. Facial mimetic outcome after reanimation was graded using the House-Brackmann scale. Primary neurorrhaphy or interposition grafting may be performed when both the proximal and distal portions of the facial nerve are available and viable facial musculature is present. If only the distal facial nerve and viable facial musculature are available, a split hypoglossal to facial nerve anastomosis is used. A proximal facial nerve to microvascular free flap is performed when the proximal facial nerve is available without distal nerve or viable musculature. A cross-facial to microvascular free flap is performed when the proximal and distal facial nerve and facial musculature are unavailable. The above methods resulted in a House-Brackmann score of III/VI in all case examples postoperatively. The method of facial reanimation used depends on the availability of viable proximal facial nerve, the location of healthy, tumor-free distal facial nerve, and the presence of functioning facial mimetic musculature.