Costal cartilage tissue regeneration after the modified first-stage autologous ear reconstruction for microtia: A...

The modified first-stage autologous ear reconstruction for patients with microtia has been part of our regular practice since 2020, with long-term follow-up revealing no thoracic complications in the patients. Our previous clinical studies systematically investigated and advocated for the critical role of preserving the intact costal cartilage membrane and its precise suturing.

This retrospective cohort study focused on primary reconstruction for congenital microtia. Patients were screened based on exclusion and inclusion criteria. Data on patient demographics and three-dimensional CT reconstructions of the costal cartilage were collected. Additionally, in vivo animal experiments were conducted to assess the characteristics of the regenerated tissue within the perichondrium.

A total of 161 ear reconstructions performed for patients with microtia were included, comprising 54 cases on the left side, 102 cases on the right side, and 5 cases on both sides. We found that suturing the preserved costal cartilage membrane in place maintained its native contour and trajectory. A direct relationship was found between advancing age, higher physical quality, and superior costal cartilage regeneration among patients undergoing the modified first-stage autologous ear reconstruction. Patients older than 10 years demonstrated a high proportion of tissue regeneration and good postoperative thoracic stability at an early stage. Furthermore, animal models revealed regenerated costal cartilage at the perichondrial suture sites in rabbits 6 months postoperatively.

We conducted long-term follow-up on patients who underwent the modified first-stage ear reconstruction and they showed no thoracic complications. It emphasized the critical importance of obtaining costal cartilage, preferably in patients 10 years of age and older, and preserving and suturing the intact costal cartilage membrane during the modified two-flap method. These findings provide theoretical support for clinically adopting this technique.