[Narrow band imaging for evaluation of laryngeal mucosal lesions]

[Contact endoscopy with narrow-band imaging for detection of perpendicular vascular changes in benign, dysplastic, and malignant lesions of the vocal folds]

BACKGROUND

Perpendicular vascular changes (PVC) are markers of tumor-induced neoangiogenesis at the vocal folds. Contact endoscopy with narrow-band imaging (CE-NBI) allows a detailed analysis of such vascular changes.

OBJECTIVE

This work intends to evaluate the potential of CE-NBI for diagnosis of benign, dysplastic, and malignant lesions of the vocal folds. In addition, it should be determined whether CE-NBI offers an additional benefit in detecting PVC compared to white-light endoscopy (WLE) and NBI alone.

MATERIALS AND METHODS

Three examiners evaluated histologically verified cases of benign, dysplastic, and malignant lesions of the larynx in WLE, NBI, and CE-NBI (n = 60). In each mode, they examined the lesion for PVC and assessed the lesion's dignity. The proportion of lesions with detected PVC, the statistical measures of performance in detecting high-grade dysplasia and carcinoma, and the interrater variability for each mode were calculated.

RESULTS

CE-NBI proved superior to the other investigated diagnostic methods in terms of detecting PVC and in terms of sensitivity and accuracy in the diagnosis of high-grade dysplasia and carcinoma. A clear association of such pathologies with PVC was seen.

CONCLUSION

CE-NBI detects PVC more frequently and reliably than the other methods investigated. The association of these vascular patterns to high-grade dysplasia and vocal fold carcinomas could be confirmed. Compared to WLE and NBI endoscopy, the diagnostic quality for detecting high-grade dysplasia and carcinoma is increased. Thus, CE-NBI can improve endoscopic differentiation between benign and malignant lesions of the vocal folds by enhancing the detection of PVC.

Evaluation of Vascular Patterns Using Contact Endoscopy and Narrow-Band Imaging (CE-NBI) for the Diagnosis of Vocal Fold Malignancy

The endoscopic detection of perpendicular vascular changes (PVC) of the vocal folds has been associated with vocal fold cancer, dysplastic lesions, and papillomatosis, according to a classification proposed by the European Laryngological Society (ELS). The combination of contact endoscopy with narrow-band imaging (NBI-CE) allows intraoperatively a highly contrasted, real-time visualization of vascular changes of the vocal folds. Aim of the present study was to determine the association of PVC to specific histological diagnoses, the level of interobserver agreement in the detection of PVC, and their diagnostic effectiveness in diagnosing laryngeal malignancy. The evaluation of our data confirmed the association of PVC to vocal fold cancer, dysplastic lesions, and papillomatosis. The level of agreement between the observers in the identification of PVC was moderate for the less-experienced observers and almost perfect for the experienced observers. The identification of PVC during NBI-CE proved to be a valuable indicator for diagnosing malignant and premalignant lesions.

Flexible transnasal endoscopy with white light or narrow band imaging for the diagnosis of laryngeal malignancy: diagnostic value, observer variability and influence of previous laryngeal surgery

Purpose

Flexible transnasal endoscopy is a common examination technique for the evaluation of laryngeal lesions, while the use of narrow band imaging (NBI) has been reported to enhance the diagnostic value of white light endoscopy (WLE). The purpose of this study is to assess observer variability and diagnostic value of both modalities and investigate the possible influence of previous laryngeal surgery on the detection rates of laryngeal malignancy.

Methods

The study was based on the retrospective evaluation of 170 WLE and NBI images of laryngeal lesions by three observers in a random order. The histopathological diagnoses serve as the gold standard.

Results

In identifying laryngeal malignancy, the sensitivity of NBI proved to be higher than that of WLE (93.3% vs. 77.0%). NBI was also superior to WLE in terms of accuracy (96.3% vs. 92%) and diagnostic odds ratio (501.83 vs. 120.65). Both modalities had a specificity of 97.3%. The inter-observer agreement was substantial (kappa = 0.661) for WLE and almost perfect (kappa = 0.849) for NBI. Both WLE and NBI showed a high level of intra-observer agreement. The sensitivity was significantly lower in images with history of previous laryngeal surgery compared to those without.

Conclusions

Flexible transnasal endoscopy has been proved to be a valuable tool in the diagnosis of laryngeal malignancy. The use of NBI can increase the sensitivity and observer reliability in that context and can also provide a diagnostic gain in cases with previous laryngeal surgery