Two-stage optical system for colorectal polyp assessments

BACKGROUND AND AIMS: Macroscopic real-time evaluations of the histopathology and degree of invasion of colorectal polyps help to select the most suitable endoscopic treatment method. Dual-focus (DF) narrow-band imaging (NBI) is a new imaging enhancement system that uses digital and optical methods to enhance the view of blood vessels on mucosal surfaces. However, the superiority of this technique over standard imaging techniques has not been previously reported. The aim of this study was to determine whether the two-stage optical systems in a new generation of endoscopes will increase the diagnostic accuracy of colorectal polyp recognition. METHODS: The study included 270 patients, and 386 colorectal polyps were diagnosed and removed. The polyps were assessed with white light and NBI using one- and two-stage optical systems, respectively. After being classified according to the Kudo pit pattern schemes, the polyps were removed and histopathologically verified. RESULTS: Regarding non-neoplastic lesions (Kudo I and II), no difference was observed in the recognition of polyps when using the NBI-DF function. We observed improved accuracy in the preliminary diagnoses of Kudo III(L) lesions (from 87.16 to 90.09 %, p < 0.05) and Kudo III(S) lesions (from 87.29 to 92.79 %, p < 0.01). NBI-DF also increased the accuracy of preliminary diagnoses of Kudo IV lesions (from 88.24 to 94.12 %, p < 0.01). The Kudo V pit patterns were also more distinct with NBI-DF imaging, increasing the diagnostic accuracy from 91.67 to 100 %. CONCLUSIONS: Using a two-stage optical system with electronic colorization of the mucosa increased diagnostic accuracy for differentiating colorectal polyps with neoplastic potential

How to improve the adenoma detection rate in colorectal cancer screening? Clinical factors and technological advancements

Introduction: Colonoscopy has been widely regarded as the gold standard in colorectal cancer (CRC) screening. Within recent years different endoscopic imaging techniques have been introduced to improve the quality of colonoscopy. The adenoma detection rate (ADR) is the single most important quality indicator for colonoscopy. The aim of this study was to evaluate the quality of CRC screening expressed by ADR in two different eras of endoscopic technology advancement. Material and methods: We conducted a dual-center study that enrolled 24 055 patients, who underwent colonoscopy as part of a national screening program. Patients were sorted into two groups according to the advancement of endoscopic equipment used for colonoscopic examination: group I - 10 405 patients examined between 2004 and 2008 (standard electronic endoscopes); group II - 13 650 patients examined between 2009 and 2014 (modern endoscopes). The ADR in two different eras and the impact of endoscopic novelties were determined. Results: The ADR in group I was 29.14%, in group II 31.73% (p < 0.001). The overall ADR was 30.88% - 38.80% and 25.95% (p < 0.001) for the male and female patients, respectively. The mean adenoma number per colonoscopy was 0.366 (95% CI: 0.357-0.375; p < 0.001), 0.337 (0.321-0.352) and 0.380 (0.369-0.392) for patients in group I and group II, respectively. Conclusions: Our study shows that technological innovation, novel endoscopy devices and diagnostic techniques improve the quality in CRC screening by increasing the ADR. However, we need to determine which of the technologies are supreme to achieve excellence in colorectal cancer screening