Nagy Naguib Naeem Naguib MD, MSc, Presenter: Nothing to Disclose

Ahmed Fathy Emam MBBCh, Abstract Co-Author: Nothing to Disclose

Constanze Hey, Abstract Co-Author: Nothing to Disclose

Nour-Eldin Abdelrehim Nour-Eldin MD, MSc, Abstract Co-Author: Nothing to Disclose

Marc Harth, Abstract Co-Author: Nothing to Disclose

Iris Burck MD, Abstract Co-Author: Nothing to Disclose

Boris Bodelle MD, Abstract Co-Author: Nothing to Disclose

Thomas Lehnert MD, Abstract Co-Author: Nothing to Disclose

Thomas Josef Vogl MD, PhD, Abstract Co-Author: Nothing to Disclose

To test whether the volume of the inner ear and cochlea measured using three dimensional (3D) reconstruction of the high resolution MRI sequence affect the speech recognition outcome following cochlear implantation. 

The study was retrospectively performed on 36 patients (17 males & 19 females) with a mean age of 53.58 year +/- 22.1. All patients suffered from longstanding sensorineural hearing loss & received unilateral cochlear implantation. High resolution MRI was performed using a T2-weighted SPACE sequence with 0.6 mm slice thickness. 3D reconstructions and pre-operative volume measurements were performed using an advantage workstation for diagnostic imaging. Speech recognition (SR) was tested using the Freiburger Monosyllabic Words (MSWT) and Numbers tests (NT) preoperatively, postoperatively, at 3, 6 and 12 month follow-up. Speech Recognition tests and Volume assessment were performed in a double blinded fashion. The correlation between the Speech Recognition test results and inner ear and cochlear volume measurements in 3D were tested for statistical significance using the Spearman's rank correlation test.

The mean 3D volume of the inner ear was 0.48 cm3 (Standard deviation: 0.08, Range: 0.31 – 0.7) and the mean 3D volume of the cochlea was 0.16 cm3 (Standard deviation: 0.03, Range: 0.1 – 0.22). The mean percentages of the SR-MSWT were 5.4, 25.19, 38.54, 46.04 and 53.85 in the preoperative, postoperative, 3, 6 and 12 month follow-up respectively. The mean percentages of the SR-NT were 30.4, 66.15, 81.6, 82.5 and 87.6 in the preoperative, postoperative, 3, 6 and 12 month follow-up respectively. There was no significant correlation (p > 0.05) between the preoperative volume of the inner ear and cochlea and the results of the SR assessment at any time point of the study.  

The preoperative volume of the inner ear and the volume of the cochlea do not correlate significantly with the outcome of the speech recognition tests following cochlear implantation.     

The current study results showed that even patients with a small volume of the inner ear or small volume of the cochlea can benefit from cochlear implantation since the volume does not influence the speech recognition outcome.  

Naguib, N, Emam, A, Hey, C, Nour-Eldin, N, Harth, M, Burck, I, Bodelle, B, Lehnert, T, Vogl, T, Three Dimensional Reconstruction of the Inner Ear Using High Resolution MR-Imaging before Cochlear Implantation: Does the Volume of the Cochlea and Inner Ear Affect the Results of Speech Recognition Outcome after Implantation?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011588.html