Hemilaryngeal Microsomia: An Anatomic Variant

Congenital crico-thyroid dysplasia: a comprehensive description

INTRODUCTION

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

CASE PRESENTATION

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.

CONCLUSION

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.

Buckled Thyroid Cartilage: An Anatomic Variant

OBJECTIVE

Anatomic abnormalities in the larynx can cause significant and bothersome symptoms. Identified here is an anatomical variant of the thyroid cartilage.

STUDY DESIGN

This study is a retrospective case series of 11 subjects diagnosed with an anatomic variant of the thyroid cartilage.

METHODS

Patients with an anatomic inward buckling of the thyroid cartilage, termed here as buckled thyroid cartilage, were identified through a 20-year retrospective chart review of a tertiary care laryngology practice.

RESULTS

We describe 11 patients with fullness or asymmetry in the area of the false vocal fold and an associated inward buckling of the thyroid cartilage on computed tomography scan. All patients presented with a bothersome voice-related complaint. The most common presenting complaints were hoarseness (54%), globus sensation (45%), or vocal fatigue (27%). One patient was found to have a history of known laryngeal trauma. Surgical correction through an external approach on one patient was successfully performed with subsequent resolution of symptoms.

CONCLUSION

We postulate that deformity and protrusion of the false vocal fold can result in a dampening effect on the vibratory capacity of the vocal fold that can lead to symptomatic hoarseness and vocal fatigue. Buckled thyroid cartilage is, therefore, an important anatomical variant to be aware of and be able to recognize.