후방접근 안면신경탐색 이하선 절제술과 수술후 안면신경 기능

Risk of Facial Palsy after Parotidectomy Using Posterior Approach to the Facial Nerve

We performed a retrospective study to evaluate the effect of posterior approach to facial nerve in parotid surgery, being the standard procedure in our hospital, on postoperative facial palsy and to access the safety of this procedure in preserving the function of facial nerve. A series of 176 parotid surgeries from 172 patients from January 1989 to December 1994 was analyzed, of which, 2 Schwannomas, 4 Kimura's diseases, 6 preoperative facial palsies, and 4 intentional nerve resections for malignancy were excluded. Factors such as pathology of tumor, extent of surgery, location of tumor, size of tumor, frequency of surgery were reviewed to determine if any factor contributed to the developement of facial palsy postoperatively. Of 160 parotidectomies, postoperative facial palsy was found in 58(36.3%), being temporary in 35(35. 6%), recovered within 12 months after surgery and permanent in 1(0.6%). Facial palsy occured in 47(35.7%) of 128 benign tumors, 42(89.5%) recovered completely within 6 months and in 11(34.4%) of 32 malignant tumors, 6(54.5%) within 6 months. Among the factors analyzed, postoperative facial palsy was found to be common in the tumors of deep lobe(p<0.02) and in total or neartotal parotidectomies(p<0.08). In our study, the factors of the location of tumor and extent of surgery would be contributable to developement of postoperative facial palsy and the surgical technique using posterior approach to the facial nerve may be a simple and safe surgical procedure for identification and preservation of facial nerve in parotid surgery.