The buckled thyroid cartilage: a rare case from practice, transcutaneous ultrasound diagnosis

Deformity of the thyroid cartilage can be caused by various causes: metaplasia, trauma, cyst, perichondritis, or tumor. Radiation diagnostic methods are used for diagnosis. Cartilage deformity unrelated to these factors is extremely rare. Objective: to demonstrate a rare case of thyroid cartilage deformity that mimicked laryngeal neoplasm, and the possibilities of echography, along with multispiral computed tomography (MSCT) and magnetic resonance imaging (MRI), in the diagnosis of this pathology. Materials and methods. Patient S., aged 47, consulted an otorhinolaryngologist due to complaints of moderate pain in the throat and neck on the left side for 2 years. The patient's voice is not affected, and breathing is unobstructed. No history of injuries was reported. Physical examination of the neck, palpation of the thyroid cartilage, fiberoptic laryngoscopy, MSCT of the larynx, and MRI were performed using a CT scanner with a magnetic field strength of 1.5T and bolus injection of a gadolinium-based contrast agent in an amount of 7.5 mL. Echography of the larynx was also performed on a LOGIQ 9 device using B-mode and color Doppler mapping (CDK). Biopsy was taken from the left vocal fold, and histological analysis of the collected tissue was conducted. Results. According to the results of fiberoptic laryngoscopy, a protrusion of the left vocal fold and a suspected tumor of the larynx were identified in the patient. Using MSCT and MRI with contrast of the larynx, an indentation of the left side of the thyroid cartilage was observed, but no large masses were detected. Echography in B-mode showed deformation of the cartilage plate and, in CD mode, deformation of the laryngeal space corresponding to cartilage deformation. Biopsy and histological examination of the larynx excluded a tumor. The patient was referred to a neurologist for further evaluation. Conclusion. This rare case demonstrates that the buckled thyroid cartilage can cause asymmetry of the internal structures of the larynx without dysphonia and breathing problems, and mimic a laryngeal tumor. Laryngeal echography made it possible to visualize not only cartilage deformity, but to visualize the soft tissues changes of the larynx, thereby being comparable in information content to MRI and MSCT.