Transmastoid Decompression of the Facial Nerve for Severe Peripheral Facial Palsy

—Relationship Between the Findings of Contrast-enhanced MRI and the Prognosis—

Abstract

Transmastoid decompression of the facial nerve, one of the treatments used for severe peripheral facial palsy, remains a controversial treatment modality. In this report, we reveal that there was no significant correlation between the enhancing portion of the lesion on MRI and the rate of progression of the palsy, except for the case of the enhancement of the horizontal segment. The hypothesis that “Among patients undergoing transmastoid decompression, cases showing enhancement of the labyrinthine segment on preoperative MRI would show worsening of the paralysis postoperatively as compared to patients who do not show such enhancement on MRI” could not be proven. Additionally, there was also no relationship between lesion enhancement observed on MRI, except for enhancement of the horizontal segment, and the inoperative findings (P=0.048). Based on these perspectives, we assume that transmastoid decompression, without decompression of the labyrinthine segment or fundus of the internal acoustic meatus may be effective for the treatment of severe peripheral facial nerve palsy.