Virtual Laryngoscopy.

Conventional endoscopy is currently the gold standard for evaluation of the upper airways, such as the larynx or the tracheal lumen. Rigid endoscopes, however, require general anesthesia, which may limit clinical application in high-risk patients, whereas flexible endoscopy depends on a cooperative patient and on a very experienced endoscopist. Furthermore, congenital anomalies or acquired stenoses may inhibit passage of the endoscope. In addition, viewing is limited strictly to the lumen, which limits the transmural evaluation of lesions. Cross-sectional imaging, using spiral computed-tomography (CT) or magnetic resonance imaging (MRI) and postprocessing of imaging data sets, may offer an additional evaluation tool for those difficult clinical situations and provide additional information about the larynx that cannot be obtained with laryngoscopy. Multiplanar reformations (MPRs), shaded surface displays (SSDs), or three-dimensional (3D) reconstructions have been the subject of research in otolaryngology-head and neck surgery (Altobelli et al. 1993; Cline et al. 1987; Eisele et al. 1994; Girod et al. 1995; Kerberle et al. 2003; Korves et al. 1995; Marsh and Vannier 1983; Schubert et al. 1996; Vannier and Marsh 1996). [ABSTRACT FROM AUTHOR]