Characterization of middle ear ossicular ligaments using photon counting detector CT

Area of Science:

• Medical Imaging
• Anatomy
• Radiology

Background:

• Middle ear suspensory ossicular ligaments were previously described using traditional CT scanners.
• Photon counting detector CT (PCCT) offers improved spatial and contrast resolution for visualizing these ligaments.

Purpose of the Study:

• To characterize the middle ear suspensory ossicular ligaments using PCCT.
• To compare PCCT findings with existing radiological descriptions of these ligaments.

Main Methods:

• Retrospective review of 100 temporal bones from 50 patients without hearing loss or middle ear pathology.
• Classification of ligaments (anterior, superior, lateral mallear; posterior incudal) and tendons (stapes, tensor tympani) based on visualization.
• Assessment of interrater agreement for reliability.

Main Results:

• Observed greater complexity and variability in anterior and superior mallear ligaments than previously reported.
• Detailed descriptions of ligamentous complexes and variant forms, including accessory ligaments.
• Characterized presence and thickness of posterior incudal, lateral mallear, stapes, and tensor tympani ligaments/tendons.

Conclusions:

• PCCT enables detailed characterization of ossicular ligaments, aligning with anatomical complexity.
• Radiologists and otologists must acknowledge the intricate anatomy of middle ear ligaments visualized by PCCT for accurate interpretation.
• Findings facilitate recognition of complex ligamentous anatomy, aiding image interpretation in temporal bone imaging.