Anthropometric measurements in 126 microtia reconstructions

Due to its complex, three-dimensional morphology, auricular reconstruction remains one of the most challenging procedures in reconstructive surgery. A subject that remains controversial, however, is the question of the growth potential of the cartilaginous framework. This study explored the anthropometric changes of the reconstructed auricle and the contralateral normal ear in a series of Asian patients.

The records of 126 unilateral microtia patients in three age groups who underwent autogenous costal cartilage auricular reconstruction between 2007 and 2010 were reviewed. The average age was 14 years, and the average follow-up was 2.5 years. The auricular height was measured as the distance from the supra-auricle to the subauricle, and the width was measured as the distance from preauricle to the postauricle. Measurements of the height and width of the reconstructed auricle and the contralateral normal side were taken at implantation and at the final follow-up. Comparisons between the three age groups were performed using a paired Student t test to examine the mean auricular heights and widths for significant interval changes in size.

The measurements showed average width increases of 1.24 mm (3.68%) and 1.35 mm (3.91%) in the reconstructed auricles of children and adolescents, respectively, but we did not find obvious changes in the adult group. No significant differences were found in the height measurement of the reconstructed auricle in the three groups. The mature size of the normal ear was reached by age 12, with slowing as patients entered adolescence and adulthood. Comparison of the reconstructed auricle and the contralateral normal ear revealed a very similar growth rate in the adult group. There were average height decreases of 0.77 mm (1.3%) and 1.3 mm (2.09%) in the reconstructed auricles of children and adolescents compared with the normal side. The results showed an average width increase of 1.13 mm (3.15%) in the adolescent group but not in the child or adult groups.

The results of this study have generated some useful parameters for the study of growth of the reconstructed auricle and contralateral normal ear. This information serves to clarify the issue of auricular framework fabrication in terms of proper size, especially for Asian patients. Further investigation and analysis are necessary to provide further proof of the graft change.