Miroslaw Szura, PhD, Krzysztof Bucki, PhD, Artur Pasternak, PhD, Andrzej Matyja, PhD, Jan Kulig, PhD. Jagiellonian University.
Macroscopic evaluation of the degree of invasion of colorectal polyps allows to choose the most adequate method of endoscopic treatment. Narrow Band Imaging is a new image enhancement system employing optic digital methods to enhance images of blood vessels on mucosal surfaces, allowing improved visualization of mucosal surface structures. However, the superiority of such an imaging over a standard one has not been reported until now.
The aim of this study is to determine if two-stage optical system in new generation of endoscopes will increase diagnostic accuracy in colorectal polyp typing.
Materials and methods:
The study comprised 270 patients, in which 386 colorectal polyps were diagnosed and removed. Polyps were assessed in white light and NBI with use of one and two-stage optical system respectively. Polyps were classified according to pit pattern scheme developed by Kudo and subsequently verified histopathologically. Evaluation was performed during colonoscopic examination as well as retrospectively on the basis of recorded images by 3 experienced endoscopists.ClinicalTrials.gov number, NCT01688557
There was no difference in the evaluation of polyps regarding the group of non-neoplastic polyps (Kudo I and II). The diagnostic accuracy was 91.6% with application of near focus function vs 89.7% with use of a standard optical system. The diagnostic accuracy of non-invasive adenomas has also risen (Kudo IIIL, IIIS, IV) (91.5% vs 87.2) P<0,05. The same observation concerned invasive lesions (Kudo V) (94.1% vs 91.7%). There were no differences in the evaluation of polyps during colonoscopy in comparison to the retrospective group.
Two-stage optical system with electronic colorization of the mucosa (NBI) increases diagnostic accuracy for the differentiation of neoplastic colorectal polyps. Preliminary evaluation of a polyp type and character remains the same precise during endoscopic examination as in retrospective analysis.