HRCT evaluation of microtia: A retrospective study

Area of Science:

• Otolaryngology
• Radiology
• Medical Imaging

Background:

• Microtia is a congenital condition affecting the external ear.
• Accurate assessment of associated ear anomalies is crucial for surgical planning and hearing rehabilitation.
• High-resolution computed tomography (HRCT) is a key imaging modality for evaluating temporal bone structures.

Purpose of the Study:

• To identify external, middle, and inner ear abnormalities using HRCT in microtia patients.
• To correlate clinical microtia grades with specific anatomic anomalies and hearing impairment.

Main Methods:

• Retrospective analysis of 52 Indian patients with microtia.
• HRCT of the temporal bone to assess ear structures.
• Clinical grading of microtia (Weerda et al. criteria) and hearing loss assessment (audiometry/brainstem-evoked response).
• Statistical correlation between microtia grades, HRCT findings, and hearing loss.

Main Results:

• High prevalence of external (93.1%) and middle (74.5%) ear anomalies.
• External auditory canal atresia and hypoplastic mesotympanum were most common.
• Lower incidence of ossicular dysplasia and facial canal anomalies, but higher cholesteatoma rates.
• No significant association between microtia grades and external/middle ear anomalies.
• Significant association found between Grade III microtia and hearing loss.
• Congenital cholesteatoma linked to pneumatization of the atretic plate and mastoid.

Conclusions:

• HRCT is effective in characterizing ear anomalies in microtia.
• Clinical grading has limited predictive value for external/middle ear anomalies but correlates with hearing loss in Grade III.
• Findings highlight the need for tailored surgical approaches considering specific anomalies like cholesteatoma.