Morphometric analysis of the internal auditory canal by computed tomography imaging

Area of Science:

• Anatomy
• Radiology
• Medical Imaging

Background:

• The internal auditory canal (IAC) displays significant inter-individual variability and structural variations.
• Understanding IAC anatomy is crucial due to its relationship with adjacent structures.

Purpose of the Study:

• To characterize the developmental morphology of the internal auditory canal (IAC) using high-resolution computed tomography (CT).
• To analyze IAC dimensions and their variations during development.

Main Methods:

• CT images of 110 subjects (aged 1-92 years) were reviewed.
• Morphological parameters including shape, area, opening width, longitudinal length, vertical diameter, and distance from the vestibular aqueduct were measured.
• Digital image processing was employed for precise measurements.

Main Results:

• IAC shapes varied, with funnel-shape being most common in both children (74%) and adults (58.3%).
• Quantitative measurements showed differences between children and adults: IAC area (50.30 mm² vs. 44.64 mm²), opening width (7.53 mm vs. 7.10 mm), length (11.17 mm vs. 9.84 mm), vertical diameter (4.82 mm vs. 4.47 mm), and IAC-VA distance (12.63 mm vs. 11.17 mm).
• Statistically significant differences in length and diameter were observed between children and adults.

Conclusions:

• The internal auditory canal (IAC) presents diverse shapes and dimensions that change with development.
• IAC length and diameter show statistically significant differences between pediatric and adult populations.
• High-resolution CT imaging is effective for detailed IAC morphological analysis.