High Definition Colonoscopy Combined with i-SCAN Imaging Technology Is Superior in the Detection of Adenomas and Advanced Lesions Compared to High Definition Colonoscopy Alone

Abstract

Background. Improved detection of adenomatous polyps using i-SCAN has mixed results in small studies. Utility of i-SCAN as a primary surveillance modality for colorectal cancer screening during colonoscopy is uncertain. Aim. Comparing high definition white light endoscopy (HDWLE) to i-SCAN in their ability to detect adenomas during colonoscopy. Methods. Prospective cohort study of 1936 average risk patients who had a screening colonoscopy at an ambulatory procedure center. Patients underwent colonoscopy with high definition white light endoscopy withdrawal versus i-SCAN withdrawal during endoscopic screening exam. Primary outcome measurement was adenoma detection rate for i-SCAN versus high definition white light endoscopy. Secondary measurements included polyp size, pathology, and morphology. Results. 1007 patients underwent colonoscopy with i-SCAN and 929 with HDWLE. 618 adenomas were detected in the i-SCAN group compared to 402 in the HDWLE group (p < 0.01). More advanced adenomas (≥10 mm) were found by i-SCAN, 79 versus 47 (p = 0.021) and based upon histology alone 37 versus 18 (p = 0.028). Conclusions. i-SCAN detected significantly more adenomas and advanced adenomas compared to high definition white light endoscopy.

Standards of diagnostic colonoscopy for early‐stage neoplasia: Recommendations by an Asian private group

“…One tandem study reported a significantly lower adenoma miss rate with i‐scan in comparison with HD WL colonoscopy, but another concluded that there were no significant differences . Moreover, one recent non‐randomized controlled study demonstrated that i‐scan had a significantly higher detection rate for adenoma and advanced adenoma in comparison to HD WL endoscopy …”

“…44 Moreover, one recent non-randomized controlled study demonstrated that i-scan had a significantly higher detection rate for adenoma and advanced adenoma in comparison to HD WL endoscopy. 45 Two meta-analyses in 2011 and 2013 confirmed the superiority of capsule endoscopy (CE) with targeted biopsy over SD WL colonoscopy with random biopsy (6% increase in the yield for dysplasia). 46,47 As a result, many international guidelines now recommend the routine use of pancolonic chromoendoscopy with targeted biopsy for neoplasia surveillance in patients with IBD.…”

Colonoscopy technologies for diagnostics and drug delivery

“…This enhances the contrast of the light and dark, therefore improving the visualization and providing a more detailed examination of the mucosal surface structure. Bowman et al () stated that surface enhancement improves the ability to distinguish between the borders of the abnormal and normal mucosa. This mode improves the efficiency of polyp detection.…”

“…The second mode is contrast enhancement. This creates a blue‐tint image as it suppresses the wavelength of red and green, allowing for the enhanced visualization of the depth of the mucosal surface (Bowman et al, ). Contrast enhancement can also be utilized to visualize irregularities, which may be unnoticed if white light colonoscopy is solely utilized (Cho, ).…”

“…The final mode is referred to as tone enhancement. This method restricts the red wavelength, thus allowing for better visualization of subtle irregularities and the structure of vessels in the mucosa (Bowman et al, ). Cho et al (2015) suggested that tone enhancement was an effective tool to characterize already identified lesions (Cho, ).…”