Effect of radiological grade of cochlear ossification on cochlear implant outcome in postmeningitis deafness

Abstract

Objectives: Cochlear implantation provides significant benefits to patients with postmeningitis deafness; however, the prediction of the outcome is difficult. Therefore, the goal was to investigate whether there is a correlation between cochlear implantation outcome in postmeningitis deafness and the radiological grade of cochlear ossification. Methods: In this retrospective cohort study conducted at King Abdulaziz University Hospital, Riyadh, Saudi Arabia, between January 2013 and December 2017, nine patients with 14 diseased ears were included. All patients with postmeningitis deafness who had cochlear ossification and underwent cochlear implantation were included. Patients' demographic data and postoperative audiological outcome were recorded. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) findings were independently reviewed by two neuroradiologists and graded for cochlear ossification. The correlation between the preoperative radiological grade of cochlear ossification and postcochlear implant audiological outcome was examined. Results: The mean duration of deafness before implantation was 6.5 months, and the average PTA4k for all included ears was 28.9 dB. The average speech reception threshold was 22.5 dB. There was no significant difference in the audiological outcome between the different radiological degrees of cochlear ossification using either MRI or CT. Conclusion: The present study showed that the radiological degree of cochlear ossification postmeningitis is not a useful predictor of the audiological outcome postcochlear implant. However, the small sample size remains a major limitation of the current study.

Keywords

• cochlear implant
• labyrinthitis ossifican
• postcochlear ossification