The Role of Intraoperative Facial Nerve Monitoring during Parotidectomy for Benign Parotid Gland Tumors

Abstract

Objectives:

1) Compare outcomes of parotidectomy with and without electrophysiologist-assisted intraoperative nerve monitoring (IOM) for the treatment of benign parotid gland tumors. 2) Recognize potential benefits of IOM in parotidectomy.

Methods:

Retrospective case control of 151 consecutive patients undergoing parotidectomy for treatment of benign tumors between March 2006 and December 2011 at Weill Cornell Medical College. Interventions included parotidectomy and IOM. Outcome measures included complications from intervention(s).

Results:

Sixty-four percent of patients were female, and the median age at surgery was 57 years (range 17 - 86 years). The majority of patients (70%) had pleomorphic adenomas. One surgeon performed all 81 parotidectomies with IOM (54%), while another surgeon performed the remainder without IOM (46%). IOM use depended on the attending surgeon and was not due to any other factor. Superficial parotidectomies comprised 81% and 70% of surgeries performed with and without IOM, respectively. Temporary facial nerve dysfunction occurred in 10.6% of patients. No statistically significant difference was seen in temporary facial nerve paralysis rates post-operatively between groups with IOM (9.9%) and those without (11.4%) (P = 0.76). In cases with IOM, electrical mapping and presence of transient nerve irritation did not influence the rate of complications (P = 0.19).

Conclusions:

Use of IOM does not appear to impact the rate of facial paralysis post-parotidectomy for benign parotid gland tumors. However, IOM may be beneficial in aiding the surgeon in difficult cases, to preserve smaller branches, or when the tumor lies particularly close to the facial nerve.