Immediate Facial Nerve Palsy Secondary to Otological Surgery: A Systematic Review and Narrative Synthesis.

Objectives: Iatrogenic facial nerve palsy following otological surgery is a devastating complication that results in adverse aesthetic and functional outcomes. This study aims to review studies that have reported cases of immediate facial nerve palsy to learn why and where injuries occurred and to assess outcomes following management.

Databases reviewed: MEDLINE, Embase, Cochrane CENTRAL, and Pubmed up to June 20, 2023.

Methods: Clinical studies of immediate facial nerve palsies following middle ear and cochlear implantation surgery were included. Risk of bias was examined using the Brazzelli risk of bias tool. Due to the inconsistency in reporting of outcomes, we were unable to perform a meta-analysis.

Results: Of 234 studies identified, 11 met the inclusion criteria. The most common causes of injury were excessive drilling, use of sharp hooks to remove disease, or disorientation of the surgeon secondary to bleeding or inflammation. Variable usage of preoperative computed tomography (CT) imaging and intraoperative facial nerve monitoring was reported. The tympanic segment was the most common site of injury. A variety of surgical techniques were employed to approach the facial nerve injury including facial nerve decompression, direct closure, and repair using an autologous nerve graft.

Conclusions: Otological surgeons should consider utilizing preoperative CT imaging to establish a three-dimensional mental image of key landmarks and anatomical variations before embarking on surgery. Intraoperative FN monitoring enables safe practice. Despite these measures, complex disease processes and hostile intraoperative conditions can present difficulty. Multiple treatment options are available to treat the underlying injury.