Histoanatomical structures of laryngeal atresia: Functional considerations

To study the histoanatomical structure of laryngeal atresia with a focus on the laryngeal functional components in order to evaluate the functional prognosis of laryngeal atresia repair.

Twenty-one consecutives cases of laryngeal atresia were diagnosed at our institution between 2009 and 2016. Morphological analysis by macroscopic exam during autopsy was performed in 19 cases. Histological study of the larynx included hematoxylin and eosin staining and protein S100 immunostaining. Our analysis focused on the vocal folds, structures of the lamina propria, cricoarytenoid joints, muscles, and innervation. For each case, associated malformations were classified into two groups: severe and moderate.

Antenatal diagnosis was suspected because of congenital high airway obstruction syndrome in nine cases (37%). Associated malformations were present in 19 cases (90%), including severe malformations in 12 cases (57%). Atresia involved the cricoid in all cases, with a residual lumen in only one case and the glottis in 18 cases. Separation between the cricoid and arytenoid cartilages was observed in all cases. Fusion of the vocal process of the arytenoids in the midline was present in 13 cases. According to the gestational age, posterior maculae flavae (MF) were present in 17 of 19 cases, with abnormal structure and median fusion in 13 cases. Anterior MF were present in nine of 18 cases, with fusion on the midline in five cases. Intrinsic abductors and adductors muscles were identifiable in all cases, with fusion of thyroarytenoids muscles in the midline in 18 cases. Both recurrent laryngeal nerves were observed in all cases.

Laryngeal atresia is generally associated with other malformations, with a high risk of fatal outcomes. We observed that the functional structures of the glottic plane were present in most cases, with the exception of MF, which were frequently abnormal.

4 Laryngoscope, 130:252-256, 2020.