الفهرس 
List of contentsOnly 14 pages are availabe for public view
 |  | from | 112 |  |  |
| | | from | 112 | | |
Abstract
The diameter of nerve is not significantly affect post-operative outcome of cochlear implantation.
Recommendation
1. Small size of cochlear nerve does not affect outcome of cochlear implantation.
2. Further studies are needed to evaluate correlation between nerve thickness and cochlear implantation outcome.
Summary
A cochlear implant (CI) is a surgically implanted neuroprosthetic device to provide a person with severe to profound sensorineural hearing loss a modified sense of sound. CI bypasses the normal acoustic hearing process to replace it with electric signals which directly stimulate the auditory nerve. A person with a cochlear implant receiving intensive auditory training may learn to interpret those signals as sound and speech. However, one third of deaf children do not develop language if they are on a CI program alone and have no sign language input (Clark 2015).
Cochlear nerve deficiency (CND) is defined by a small or absent cochlear branch of the vestibulocochlear nerve(VCN) or cochlear nerve (CN). CND has been found in 3 to 21% of patients with congenital sensorineural deafness (Blaser et al,.2012 and Chen et al., 2015).
Imaging plays an important role in the workup of CI candidates to identify inner ear congenital and acquired abnormalities or cochlear nerve anomalies but also to detect temporal bone abnormalities , High-resolution computed tomography(HRCT) and three-dimensional magnetic resonance imaging (3D MRI) are imaging techniques used to diagnose CND (Mohamed et al.,2017).
This study is conducted to study correlation between cochlear nerve size & CI outcome.
Aim of the work:
To evaluate effect of cochlear nerve size on CI outcome in children.
Subjects:
Thirty cochlear implant children, their age ranged between 4 to 13 years old, 14 males and 16 females. The cause of hearing loss was varied: they were due to non-syndromic heredofamilial (85%), post febrile (5%), Auditory Neuropathy (2%) and 8% of the cases there is no definite cause of hearing loss could be determined.
All subjects were implanted with a MEDEL device at Sohag university hospital.
Pre-operative CT on temporal bone and MRI on cochlea and internal auditory canal were done for all the patients.
Post-operative C and T level in map, ECAP, 1st spoken word, 1st detected sound and LittlEars Arabic Questionnaire were done for all the patients.
So, this study showed that the diameter of the nerves was not significantly correlated to postoperative audiologic performance, but the outcome indirectly reflects the residual capability of the cochlear nerve.