Morphometric Analysis of the Internal Auditory Canal by Computed Tomography Imaging


Sergio Ricardo Marques 1 , * , Sergio Ajzen 2 , Giuseppe DIppolito 2 , Luis Alonso 1 , Sadao Isotani 3 , Henrique Lederman 2

1 Department of Morphology and Genetics, Sao Paulo Federal University, [email protected], Brazil

2 Department of Diagnosis by Image, Sao Paulo Federal University, Brazil

3 Institutes of Physics, Sao Paulo Federal University, Brazil

How to Cite: Marques S R, Ajzen S, DIppolito G, Alonso L, Isotani S, et al. Morphometric Analysis of the Internal Auditory Canal by Computed Tomography Imaging, Iran J Radiol. Online ahead of Print ; 9(2):71-78. doi: 10.5812/iranjradiol.7849.


Iranian Journal of Radiology: 9 (2); 71-78
Published Online: June 30, 2012
Article Type: Research Article
Received: January 30, 2011
Accepted: June 25, 2012


Background: Many clinical and experimental studies have been done to analyze the anatomical and functional aspects of the internal auditory canal (IAC) in human beings since there are great inter-individual variability and structural variations that may occur regarding the other adjacent structures.

Objectives: The purpose of this study was to characterize the morphology of the internal auditory canal (IAC) during development using high resolution computed tomography (CT) and to analyze its dimensions, which will be determined by measuring the nearby areas and structures using a system of digital image processing.

Patients and Methods: CT images of the IAC of 110 normal subjects aged 1 to 92 years (mean age, 46.5 years) of both genders were reviewed to determine the shape, area, opening width (OW), longitudinal length (LL), vertical diameter (VD) and distance from the vestibular aqueduct.

Results: The shapes observed in children and adults were funnel-shaped (74% and 58.3%, respectively), cylindrical (22% and 30.9%, respectively) and bud-shaped (4% and 10.8%, respectively). The measurements by CT in children were: area= 50.30 mm2, OW = 7.53 mm, length = 11.17 mm, VD = 4.82 mm and the distance between the IAC and the vestibular aqueduct (VA) = 12.63 mm. In adults, the measurements were: area = 44.64 mm2, OW = 7.10 mm, length = 9.84 mm, VD = 4.47 mm and the distance between IAC and VA = 11.17 mm.

Conclusions: CT images showed that the IAC has different shapes and when the measurements obtained for children were compared with those of adults, the parameters that presented statistically significant differences in either gender were length and diameter.

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