Cochlear implantation: Diagnosis and treatment

Abstract

Background: Cochlear implantation an effective medical procedure that can provide a valuable opportunity for children with congenital hearing loss and deafness to recover from speech and attend normal schools. Cochlear implant has the potential to improve the quality of life and facilitate social interaction for hearing-impaired individuals. It has been observed that by performing the cochlear implant surgery according to the established criteria, a possibility of recovery from deafness due to complicationin the auditory system is feasible. According to the WHO data, in January 2022, 700,000 cochlear implant surgeries were performed in more than 100 countries worldwide. From 2012 to 2022, a total of 324,200 children underwent cochlear implant surgeries. According to the 2024 data, the Department of Otolaryngology, First Central Hospital of Mongolia has implanted cochlear implants from the Med-el company in 206 children and adults. Materials and Methods: Methods and Techniques: We conducted a study involving 33 cases that met the inclusion criteria for surgical implantation of a bone graft at the Department of ENT, First Central Hospital of Mongolia (FCHM) from 2016 to 2023, using a retrospective design. The TBCT were evaluated using a 10-point system developed by Sanjay Vaid et al. We sampled the duration of surgery and the documented complications from the medical history and compared these with the imaging features from the TBCT scans. All participants in the study were operated on by a single surgery team. The surgical duration was calculated from the start of the incision to the completion of suturing. Surgical complications were classified according to the Clavien-Dindo classification. Statistical analysis was performed using SPSS version 25. Results: We studied a total of 33 cases of cochlear implantation surgery involving 27 individuals aged 1 to 58 years. Among the participants, 25 (75.7%) were male and 8 (24.3%) were female, with an average age of 9.6 ± 11.6 years. The duration of surgery ranged from 70 to 150 minutes (100.8 ± 20), and the Shapiro-Wilk test indicated that the duration was approximately normally distributed (p=0.143).Complications were noted in the study participants, with 2 (6.01%) experiencing Grade I complications, 3 (9.1%) Grade II complications, and 1 (3.03%) Grade III complications. Changes were observed in various anatomical features: mastoid pneumatization in 19 (57.6%), facial nerve anatomy in 2 (6.1%), facial nerve positioning in 10 (30.3%), position of the high jugular bulb 4 (12.1%), posterior wall of the external auditory canal and sigmoid sinus 10 (30.3%), posterior wall of the external auditory canal and the base of the cochlea 22 (66.7%), auditory ossicle connection at the base of cochlea 10 (30.3%), and positioning of the internal auditory canal in 14 (42.4%). When comparing CT measurements with the duration of surgery using Pearson’s correlation coefÏcient, significant relationships were found for mastoid pneumatization (p=0.16), facial nerve anatomy (p=0.0001), auditory ossicle connection at the base of the cochlea (p=0.003), and positioning of the internal auditory canal (p=0.003). Conclusion: Computed tomography (CT) is a non-invasive imaging technique that provides three-dimensional images of the cochlear structures with high resolution, making it a valuable tool in audiological practice to assess the condition of the cochlea and facilitate anatomical evaluation before cochlear implantation.