Adib Molaei Sisakht - Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Seyed Basir Hashemi - Otolaryngology Research Center, Khalili Hospital, Shiraz, Iran.
Leila Monshizadeh - Otolaryngology Research Center, Khalili Hospital, Shiraz, Iran.

Introduction:Since ۲۰% of the patients with sensorineural hearing loss have confirmed radiographically inner ear malformation, this study aimed to compare the incidence rate of intra and postoperative complications of cochlear implantation amongst the patients with or without inner ear malformations. Materials and Methods:In this retrospective study, we evaluated the medical record of ۹۵۴ patients who had undergone cochlear implantation. Seventeen patients had inner ear malformations and were selected as the case group, and ۲۵ patients with normal inner ear were selected as the control group. Patient’s information; including intraoperative complications, post-operative complications and neural response telemetry (NRT) immediately after the surgery were recorded. Finally, the collected data were analyzed, using the SPSS software, version ۲۱.Results:According to the CT-scan findings, the most observed internal ear abnormality was the temporal bone Mondini in ۸ patients (۴۷%), and the next inline was the common cavity at a frequency of (۲۳.۵۲%). Cerebrospinal fluid (CSF) gusher was detected in ۱۱ patients (۶۴.۷%) of the case group, which was significantly higher than the other group. This includes mild CSF gusher in ۷ cases (۴۱.۱۷%) and severe CSF gusher in ۵ cases (۲۹.۴۱%). Interestingly, no significant post-operative complications were observed in either group, minor side effects were limited and not significantly different.Conclusion:In conclusion, despite the limitations of cochlear implantation surgery amongst patients with inner ear malformation with potential risk of early or late complications, it can still be recommended as an appropriate procedure to acquire hearing as well as auditory and speech perception.

Cochlear Implantation, Inner ear malformation, Complications, Gusher