We describe a first case of human congenital crico-thyroid dysplasia associated to a right sided aortic arch and an aberrant subclavian artery.

Our patient presented with a two-weeks history of acute dyspnea, and reported hoarseness since his childhood. An urgent tracheotomy was performed, followed by direct laryngoscopy. Endoscopic examination showed a deviation of the dorsoventral axis of the larynx, with an obstructive submucosal swelling the area of the right false cord and aryepiglottic fold. Computed tomography conducted the following day confirmed the crico-thyroid dysplasia, an infected laryngocele, and the presence of a right sided aortic arch and an aberrant subclavian artery.

The embryological basis of these anomalies is attributed to congenital defects of the development of the fourth and sixth pharyngeal arches. To our knowledge, the congenital crico-thyroid dysplasia has not been previously reported in human. This case underscores the importance of recognizing anatomical variations in laryngeal cartilages, understanding their embryological origins, and potential associated malformations.