Clinical analysis of 592 patients with microtia.

Clinical and statistical analyses were performed on 592 patients who visited our hospital between April 1968 and March 1995. The preponderance in men (64.7%) and right-side (58.4%) was distinct statistically. The material shows that grade III microtia, peanut-shell type, was the most frequent with 56.8%. It is complicated with congenital stenosis or atresia in most cases (92.0%). The degree of anomalies of the auricle and external auditory meatus was generally interrelated. Ten cases of familial microtia were discovered, and all parent-child cases were father-child. About 27.9% of the patients' mothers had had a cold, threatened abortion, gestosis, anemia, etc during their pregnancy. Except for 6 patients with Treacher-Collin's syndrome and 2 patients whose mothers took thalidomide during pregnancy, we could not demonstrate the cause of the microtia, whether general or environmental.