Influence of 125I seed interstitial brachytherapy on recovery of facial nerve function

Abstract

Objective To study the influence of 125I seed interstitial brachytherapy in parotid region on the recovery of facial nerve function. Methods A total of the data of 21 patients with primary parotid carcinoma were treated with resection and 125I interstitial brachytherapy. All the patients had no facial palsy before operation and the prescribed dose was 60 Gy. During 4 years of follow-up, the HouseBrackmann grading scales and ENoG were used to evaluate the function of facial nerve. According to the modified regional House-Brackmann grading scales, the facial nerve branches of patients in affected side were divided into normal and abnormal groups, and were compared with those in contra-lateral side.Results Post-operation facial palsy occurred in all the patients, but the facial palsy recovered within 6 months. The latency time differences between affected side and contralateral side were statistically significant in abnormal group from 1 week to 6 months after treatment ( t = 2.362, P = 0.028 ), and were also different in normal group 1 week after treatment ( t = 2.522, P = 0.027 ). Conclusions 125I interstitial brachytherapy has no influence on recovery of facial nerve function after tumor resection and no delayed facial nerve damage. Key words: 125I seed; House-Brackmann grading scales; Electroneurography ( ENoG ); Latency time (LT)