Laryngeal Radioanatomy

Abstract

The larynx, a specialized segment of the airways, is the essential organ of phonation, breathing and protection of the lower airways when swallowing by a complex anatomic structures organized around a cartilaginous skeleton. We realized a prospective study on three months, ranging from March 01 to May 31 2020, of patients referred to our service for cervical CT scan or MRI exploration in different contextes. We retained the normal exams. For scanographic exploration we used a multi-slice CT scan consisting of 64 rows of detectors. Helical acquisition in native axial slices 0.627 mm thick from the base of the skull to the arch of the aorta was performed in indifferent breathing after asking the patient not to swallow. Iodinated contrast product was injected according to the administration protocol in a single bolus of 90 ml at an average flow rate of 1.5 ml / s and to perform the acquisition with 50 second delay. A dynamic phonation maneuver (saying “eee” continuously and evenly) was used to analyse the true and false vocal cords. On MRI exploration of the larynx, we used a high-field device (1.5Tesla) with a semi-circular specific surface antenna, the phase oriented in an anteroposterior direction, the 3DT1 spin echo sequence without fat signal saturation was performed. In ultrasound, we used literature data. Knowledge of laryngeal radioanatomy contributes to the diagnosis of laryngeal cancers which occupy an important place in all cancers of the upper aerodigestive tract. They can be diagnosed early and the refinement of their endoscopic exploration and imaging allows them to make a precise extension assessment.