Abstract：Objective: Knowledge of the normal cochlear nerve canal(CNC), internal auditory canal(IAC) and cochlear nerve(CN) is necessary during preoperative evaluation for cochlear implantation(CI) in infants. The purpose of this work was therefore to measure the dimensions of the CNC, IAC and CN. In addition the mean values(x±SD) were compared to analyse the difference between infants and adults. Methods: Thirty infants and thirty adults were studied who had underwent HRCT of the temporal bone. Moreover twenty infants and twenty adults were also studied who had underwent MRI of IAC. No patient had a prior history of sensorineural hearing loss(SNHL) and bony abnormalities of the inner ear. The diameters of IAC and CNC were measured on transverse HRCT. And the diameter of the CN in IAC was measured using 3D FIESTA sequence. Mean values were compared between the ears of infants’ and adults, and statistical analysis was done. Results: Mean±SD measurements(in mm) of these structures in infants and adults were as follow: CNC(transverse section) 1.92±0.25 and 1.84±0.19; IAC 4.92±0.69 and 5.04±0.59; CN 1.06±0.08 and 1.02±0.11. There was no significant difference in all of the measurements between infants and adults. Conclusion: There was no difference in the dimensions of CNC, IAC and CN between infants and adults.
2013, Vol. 24 
