Middle ear morphology and mastoid pneumatisation: a computed tomography study

Area of Science:

• Otolaryngology
• Radiology
• Human Anatomy

Background:

• Mastoid pneumatisation is influenced by factors like race, sex, and adjacent middle ear structures.
• Understanding these influences is crucial for interpreting middle ear conditions.

Purpose of the Study:

• To determine mastoid air cell system (MACS) volume.
• To investigate the relationship between MACS volume and middle ear structures.
• To assess the influence of sex on MACS volume and Eustachian tube length (ETL).

Main Methods:

• A cross-sectional study analyzed 100 computed tomography (CT) scans.
• Measurements included MACS volume, ETL, and aditus ad antrum dimensions.
• Statistical analysis was performed to identify correlations and sex-based differences.

Main Results:

• Mean MACS volume was 5.43 cm³ (right) and 5.54 cm³ (left).
• Mean ETL was 24.55 mm (right) and 24.24 mm (left).
• Significant differences in MACS volume and left ETL were found between sexes; a low positive correlation existed between aditus ad antrum height and MACS volume.

Conclusions:

• Mastoid pneumatisation is greater in men than in women.
• A low positive correlation was noted between mastoid volume and ETL, and right mastoid volume and aditus ad antrum height.
• Eustachian tube length does not appear to significantly affect mastoid air cell system pneumatisation.