# Cochlear Implantation After Temporal Bone Fracture: A Systematic Review of Preoperative Predictors and Timing

## TL;DR

Cochlear implants can effectively restore hearing in patients with intact cochlear nerves after temporal bone fractures when implanted promptly.

## Contribution

This systematic review identifies preoperative predictors and optimal timing for cochlear implantation after temporal bone fractures.

## Key findings

- Cochlear implants provide meaningful auditory benefit when the cochlear nerve is intact.
- Prompt implantation within 12 months improves outcomes by reducing cochlear ossification.
- Radiological and electrophysiological assessments are essential for identifying suitable candidates.

## Abstract

What are the main findings?
Cochlear implantation is a viable treatment option after temporal bone fractures when the cochlear nerve is anatomically intact.Preoperative radiological and electrophysiological assessments are crucial for candidates’ detection and surgical strategy.Most included studies exhibit meaningful speech benefit.

Cochlear implantation is a viable treatment option after temporal bone fractures when the cochlear nerve is anatomically intact.

Preoperative radiological and electrophysiological assessments are crucial for candidates’ detection and surgical strategy.

Most included studies exhibit meaningful speech benefit.

What are the implications of the main findings?
Timely implantation limits post-traumatic cochlear ossification and may result in improved outcomes.Trauma-related sequels are not so frequent and do not preclude successful placement and outcomes.Cochlear implantation, based on these limited observational data, is preferred over Auditory Brainstem Implantation.

Timely implantation limits post-traumatic cochlear ossification and may result in improved outcomes.

Trauma-related sequels are not so frequent and do not preclude successful placement and outcomes.

Cochlear implantation, based on these limited observational data, is preferred over Auditory Brainstem Implantation.

Background/Objectives: Cochlear implants (CIs) constitute a viable method for auditory rehabilitation in patients with profound sensorineural hearing loss after temporal bone fractures (TBFs). These patients comprise a challenging population due to the anatomical deformity and neural injury. Methods: By performing this systematic review, we attempted to evaluate the viability of CIs in the context of TBF. The literature search, across Pubmed/MEDLINE, Scopus and Google Scholar, was performed under the PRISMA guidelines. The selected time period was from December 1995 to September 2025. The final analysis included 11 manuscripts. The majority of the studies were retrospective case series with a moderate risk of bias. Results: The primary outcome was postoperative auditory function, evaluated with speech perception tasks and aided sound-field pure-tone audiometry. The secondary outcomes were the report of radiological and electrophysiologic prognosticators of implants’ viability, timing of surgery, procedural feasibility and complications. Across the studies, CIs conferred meaningful auditory benefit when the cochlear nerve was intact. High-Resolution Computed Tomography (CT) was utilized for TBF classification and cochlear patency, whereas Magnetic Resonance Imaging (MRI) and a promontory test were crucial for the assessment of neural integrity. Prompt placement, optimally within 12 months after trauma, was related to improved outcomes by limiting cochlear fibrosis and ossification. Despite patients’ impedance fluctuation, restricted speech perception in noise and frequent abnormal facial nerve excitation, the overall audiologic and speech discrimination results are comparable to non-trauma recipients. Conclusions: A CI appears to be the choice of treatment over auditory brainstem implants, as long as the cochlear nerve remains intact. Rapid implantation in well-selected patients coupled with ordinal mapping and follow-up can restore dysfunctional hearing and improve patients’ quality of life.