Preferential Associated Malformation in Patients With Anotia and Microtia.

Objective: Few epidemiological studies have investigated the external ear malformations anotia and microtia. The authors' study aimed to investigate the relationships between age, sex, type of microtia, and birth place and associated malformation as seen in 1 private Japanese clinic.

Methods: Cases of anotia/microtia that presented in Nagata Microtia and Reconstructive Plastic Surgery Clinic (Saitama, Japan) between 2005 and 2018 were included in the study. The authors identified 1896 patients with anotia/microtia with or without associated malformation. Most were primary cases, with some secondary reconstruction cases wherein the primary surgery was performed at another hospital. Cases were classified with Nagata classification; lobule type, small concha type, concha type, and anotia. Cryptotia was also observed in this study.

Results: Among the patients, 61.1% were male, 85.4% had unilateral defects (69.0% LB), and 59.1% had a right-sided defect. Most patients were less than 1 year old (15.0%) or 8 to 10 years old (5.5%-6.3%) on first examination, while 58% were from the Kanto region, including Tokyo. Regarding concomitant disorders, 32.7% had an accompanying malformation, while 13.3% had associated syndromes (eg, craniofacial microsomia, Treacher Collins syndrome). To conclude, in the authors' clinic, most cases of anotia/microtia were LB, unilateral, and seen in male patients. Information regarding several characteristic clinical features was obtained, especially that clefts and musculoskeletal deformities of the skull/face and jaw were the main accompanying malformations.