Outcomes of Cochlear Implantation in Post-lingually Deaf Patients

Introduction: Cochlear implantation has been mentioned as the most effective therapeutic intervention in deaf patients and especially those with post-lingual deafness. We aimed to assess hearing improvement of post-lingually deaf patients after cochlear implantation. Materials and methods: in this cross-sectional study all the post-lingually deaf patients who had undergone cochlear implantation (CI) surgery between December 2010 and February 2016 were assessed. Patients were recalled and after explaining the study process and signing an informed consent form, an audiometry was done by a single audiologist. In addition, demographic information, cause of hearing loss, age of onset, history of hearing aid use and surgical complications were recorded in a pre-designed checklist. Results: Twenty-nine male and 21 female with a mean age of 22.52±19.45 years underwent analysis. Most of patients (80%) had progressed condition since childhood. Sudden sensorineural hearing loss (SSNHL) was the most prevalent (10%) known etiology of deafness followed by meningitis (6%), Trauma (2%) and ototoxic drugs (2%) in the remaining 20% of the patients. Patients had the highest mean (37.1±12.61 dB) in 4000 Hz frequency and the lowest mean of hearing threshold level (32.6±8.37 dB) was for 1000 Hz frequency. Mean hearing threshold level was significantly lower in patients with lower ages of cochlear implantation (p=0.435). Patients with higher ages of deafness onset showed lower degree of hearing improvement (p=0.462). Conclusion: The results of our study suggest that cochlear implantation significantly improves hearing function of post-lingual patients and can be considered as a certain cure for these patients in Iran