Endoscopic high-frequency ultrasound of the larynx.

Over the last few years the development of new high-frequency ultrasound equipment has improved the application and resolution of endoluminal ultrasound. Following our in vitro study on the anatomical basis of endolaryngeal high-frequency ultrasound we present the preliminary results of our sonographic examinations during microlaryngoscopy in order to characterize clinical applications. For the present study 38 patients underwent endolaryngeal ultrasound examinations. Laryngeal pathology included vocal fold polyps, laryngeal cysts, chronic laryngitis, Reinke's edema, epithelial dysplasia and cancer. The ultrasound examination was performed during microlaryngoscopy in a standardized pattern. A newly developed ultrasound apparatus was utilized with 10 MHz and 20 MHz catheters. Site, size and depth of the laryngeal lesion were evaluated. In 23 examinations of laryngeal carcinomas tumor size and infiltration could be measured and involvement of the thyroid cartilage or anterior commissure could be visualized. The exact extension of laryngeal cysts could also be seen. Ultrasound added no additional information to the endoscopic impression of the other laryngeal lesions. Present findings suggest that endoluminal high-frequency ultrasound might supplement microlaryngoscopy in the assessment of certain laryngeal lesions, especially for the evaluation of the size and infiltration of laryngeal tumors and to perform a more accurate preoperative staging without using computed tomography or magnetic resonance imaging.