3D morphometric analysis of the human incudomallear complex using clinical cone-beam CT

Area of Science:

• Medical Imaging
• Anatomy
• Biophysics

Background:

• Human middle ear morphology exhibits substantial variation.
• This anatomical variability may influence auditory perception and hearing transfer functions.
• Existing morphological studies often rely on cadaveric temporal bones, limiting surface detail.

Purpose of the Study:

• To perform statistical shape analysis on the incudomallear (IM) complex using clinical cone beam CT (CBCT) scans.
• To precisely model the average geometry and population variations of the IM complex.
• To compare findings with existing literature and discuss the benefits of statistical shape modeling.

Main Methods:

• Utilized statistical shape analysis on 123 healthy human ears from 100 clinical CBCT scans.
• Achieved a scanning resolution of 150 μm, capturing detailed surface information of the IM complex.
• Did not make a priori assumptions about the anatomical structures.

Main Results:

• Generated a high-precision statistical shape model of the incudomallear complex.
• Reported mean values, variations, and correlations for key anatomical features including lengths, angles, and moments of inertia.
• Identified overall size and the incudomallear angle as primary sources of variation.

Conclusions:

• Statistical shape modeling provides a compact and precise representation of middle ear anatomy.
• This method offers significant benefits for surface modeling and understanding anatomical variations.
• The findings contribute to a better understanding of the relationship between middle ear morphology and hearing function.