Clinical Characteristics, Concomitant Malformations and Hearing Status in Congenital Microtia - A Retrospective Analysis of 635 Cases

Abstract

Purpose

This study aims to investigate the clinical characteristics of congenital microtia, providing valuable insights for its diagnosis and treatment.

Methods

A retrospective analysis was conducted on the medical records of 635 patients with congenital microtia admitted to our hospital between July 2017 and July 2021. Patients were categorized based on the presence of concomitant malformations, including craniofacial, cutaneous, and limb skeletal deformities. Mastoid CT scans were used to assess the prevalence of inner ear malformations and middle ear inflammation. Additionally, pure-tone audiometry and auditory brainstem response (ABR) tests were performed to compare the median hearing thresholds across various frequencies, including air conduction, bone conduction, and ABR.

Results

Of the 635 patients, 111 (17.5 %) exhibited concomitant anomalies. The most common associated anomaly was craniofacial deformities, found in 39.6 % (44 out of 111) of cases. A statistically significant correlation was observed between the severity of auricular deformity and the presence of concurrent craniofacial anomalies (P < 0.05), but no significant correlation was found with other associated anomalies. Furthermore, a significant association was observed between deformities of the external auditory canal and middle ear inflammation (P < 0.05), while no significant link was found between external auditory canal deformities and inner ear malformations. The severity of auricular deformity was significantly correlated with medium to low-frequency air conduction pure-tone hearing thresholds in the 0.25–2 kHz range (P < 0.05), while no significant correlation was identified with high-frequency air conduction thresholds above 2 kHz. Finally, no significant correlation was found between bone conduction pure-tone hearing thresholds, ABR, and the severity of auricular deformity (P > 0.05).

Conclusion

This study provides a comprehensive analysis of the clinical characteristics of congenital microtia. It reveals a clear correlation between increased severity of auricular deformity and a higher likelihood of associated craniofacial anomalies. Additionally, higher thresholds for medium to low-frequency air conduction hearing were linked to more severe auricular deformities. Furthermore, individuals with narrower external auditory canals had a higher prevalence of middle ear inflammation.