Aditus ad Antrum on Normal Temporal Bone CT Scan

Area of Science:

• Anatomy and Morphology
• Temporal Bone Imaging
• Otology

Background:

• The aditus ad antrum connects the tympanic cavity to the mastoid antrum, crucial for ventilation.
• Limited research exists on the detailed anatomy and morphology of the aditus ad antrum.
• Understanding this structure is vital for otological procedures and understanding temporal bone diseases.

Purpose of the Study:

• To investigate the anatomy and morphology of the aditus ad antrum.
• To evaluate the correlation between aditus ad antrum morphology and mastoid pneumatization.
• To utilize 3D multiplanar reconstruction (MPR) CT scans for detailed analysis.

Main Methods:

• Cross-sectional descriptive study of 101 normal temporal bone CT scans (190 ears) from individuals aged 16+.
• Analysis of the aditus ad antrum in axial, coronal, and sagittal planes using 3D MPR reconstruction.
• Classification of aditus ad antrum morphology and assessment of correlation with mastoid pneumatization, gender, and ear side.

Main Results:

• Aditus ad antrum morphology was classified into four groups, with Group 2 being most common (48.42%).
• No significant correlation was found between aditus morphology and gender or ear side.
• Mastoid pneumatization did not correlate with aditus morphology, though dimensions changed with increasing pneumatization.
• Bilateral symmetry in aditus morphology was observed in 45% of individuals with two normal ears.
• Males had a significantly larger mean transverse aditus diameter than females (p < 0.05).
• The anterior-posterior diameter was significantly greater in the right ear compared to the left within the same individual (p < 0.05).

Conclusions:

• Aditus ad antrum morphology can exhibit differences between the left and right ears in normal individuals.
• Aditus ad antrum morphology is not associated with the degree of mastoid pneumatization.
• Findings provide insights into normal temporal bone anatomy and potential asymmetries.