Morphology of the internal auditory canal : deriving parameters from computer tomography scans. An observational STROBE-MR study

Abstract

Person-specific three-dimensional computational modelling plays a vital role in modern-day research of cochlear implants to assist in understanding the neural interface of the cochlea and implanted electrode array. Further improvements are made to these models as more parameters are included. Landmark assessment provides information and is frequently used to register coordinates for model generation as it captures small variations. OBJECTIVES : The objective of this study is to identify and define landmarks to adequately describe the internal auditory canal for inclusion in three-dimensional computational models of the cochlea and its surrounding structures. PARTICIPANTS : Computer tomography scans of live human cochleae were collected in the retrospective period. Descriptive and comparative statistics were used to describe the data obtained from the scans. RESULTS : The mean anterior-posterior (AP) diameter at the base of the basal turn, the diameter of the AP at the midpoint of the IAC, and the anterior and posterior length of the internal acoustic canal were measured. 57.14% of the internal acoustic canals observed presented with a cylindrical, 40.48% was funnel-shaped and 2.38 % were bud-shaped. A statistically significant differences were found between the diameters of male and female internal acoustic meatus. CONCLUSIONS : This paper serves as a reference that provides a set of references for the description of the internal acoustic canal for inclusion in three-dimensional computational reconstruction of the cochlea and surrounding structures.