Oral PresentationsP69 each laryngeal condition, which can serve as a criteria for further laryngoscopic examinations and diagnosis.Methods: This study was conducted between January 2012 and October 2013 at the Department of Otolaryngology, the second hospital attached to Jilin University (Changchun Jilin, China). A total of 3675 patients (2092 males, 1583 females; mean age 50.2 ± 19.5 years) were enrolled in this study. All 3675 patients underwent laryngoscopy equipped with conventional white light and NBI system. A total of 1153 lesions were classified into different groups according to their histopathological results.Results: On NBI view, mucosa of a normal vocal fold was light brown. Intraepithelial vessels displayed blue-green, which were in striking contrast to the surrounding mucosa. Polyps demonstrated a color of light green. Cysts and mucocele appeared as light white. Leukoplakia was shown as a white color and hyperplastic epithelial lesions appeared as a slightly brownish color. Erythroplakia appeared as welldistributed dark brown lesions. Pachydermia displayed light white with a quite different shape from that of cysts. Papilloma were shown as quite delicate green. Abnormal submucosal microvessel changes visualized in laryngeal carcinoma lesions were shown as typical scattered dark brownish spots. Sensitivity and specificity for the diagnosis of malignancy by means of NBI view calculated from these results were 98.81 and 99.89%, respectively.Conclusions: The advent of NBI is a breakthrough in the field of assessing laryngeal diseases, especially malignant ones.