Accuracy of flexible versus rigid laryngoscopic photo-documentation in the diagnosis of early glottic cancer

Abstract

To compare the image quality provided by rigid laryngoscopes versus flexible distal-chip laryngoscopes when documenting the same laryngeal pathology. This paper reports a prospective single-blind study. Ten early stage glottic cancer cases were selected. Photographs of the pathologies were taken using both rigid and flexible distal-chip laryngoscopes (a total of 20 photographs). Nineteen clinicians were asked to review the laryngoscopic photographs; the clinicians were provided with a worksheet, which included questions regarding the clinical description, photograph quality and overall satisfaction with the images obtained. Clinicians’ responses to the worksheet questions were then analysed. The overall accuracy rate for lesion sidedness, anatomical sub-site involvement, anterior commissure involvement and tumour staging were 94.7 per cent, 46.6 per cent, 53.7 per cent and 47.1 per cent respectively. There were no statistically significant differences in terms of the accuracy rates, photograph quality or overall satisfaction with the photographs obtained by either modality. There were no statistically significant differences demonstrated in overall clinical accuracy or perceived image quality between the use of the rigid or flexible endoscopes when interpreting images of early glottic cancer.