3-DIMENSIONAL IMAGING OF THE HYPOPHARYNX AND LARYNX BY MEANS OF HELICAL (SPIRAL) COMPUTED-TOMOGRAPHY - COMPARISON OF RADIOLOGICAL AND OTOLARYNGOLOGICAL EVALUATION

A new computed tomography (CT) technology, helical (spiral) CT, allows the entire neck to be imaged in only 30 seconds. Although multiplanar and three-dimensional (3-D) imaging could be performed with conventio nal CT, the volumetric acquisition provided by helical (spiral) CT all ows significantly improved quality and easier reconstruction for more applications. These 3-D models show an airway appearance similar to th at obtained with laryngography. Independent review of the 3-D images i n 12 patients with lesions by two radiologists and one otolaryngologis t was performed to assess 1) image quality, 2) ability to judge lesion extent, and 3) assistance in understanding the lesion compared to tha t provided by routine axial scans. Rating scores of 1 to 5 were assign ed, with 5 representing the best quality or greatest value. The result s showed that both groups scored image quality equally: 4.7. Lesion ex tent for the radiologists was 2.6, while the otolaryngologist's rankin g was 3.7 (p < .01). In assisting understanding of lesions versus axia l scans, radiologists ranked 3-D images 2.1, while the otolaryngologis t ranked them 3.1 (p < .01). In summary, 3-D models provide a compleme ntary imaging technique in understanding upper airway disease.