Stereoscopic display of a three-dimensional image of the larynx using high-speed helical scanning.

To evaluate the usefulness of stereoscopic images of larynges using helical CT in stereo mode, a retrospective review of the characteristics of stereoscopic viewing of larynges was made. The subjects were 3 patients with laryngeal cancer, 1 patient with laryngeal leiomyosarcoma and 1 patient with an advanced tongue carcinoma whose formalin-fixed larynx was extirpated. The larynges were scanned by high-speed helical CT using 1- to 2-mm slices. The reproduction of stereographic images was performed by the manipulation and rotation of three-dimensional structures around the y-axis on the computer display. The three-dimensional images of the complex structures, such as the arytenoid cartilage, aryepiglottic fold and pyriform sinus, were better observed by binocular images (stereograms) than by monocular images. Stereoscopic views of the larynx are useful in producing three-dimensional images of the unseen inner surface of the human body.