Abstract
Early detection and removal of adenomatous polyps can prevent the development of colorectal cancer. However, it is fairly common— up to 20%— for polyps to be undetected in a colonoscopy due to poor visualization of the proximal aspect of colonic folds and anatomical flexures. To overcome these limitations, many new endoscopes and accessories have been developed. A wide-angle colonoscopy did not improve the detection of adenoma compared with the standard colonoscopy. An extra-wide angle and Retroview colonoscopies showed a significantly lower miss rate of polyps in the colon model. However, clinical trials are mandatory in the future. The recently introduced full spectrum endoscopy system showed a significantly higher adenoma detection rate than the standard forward-viewing colonoscopy. In accessories, The cap-assisted colonoscopy showed only a marginal or no benefit on the detection of polyps and adenomas. In contrast, a colonoscopy with Endocuff, EndoRings, and G-eye have showed significantly lower adenoma miss rates. The Third Eye, which provides additional retrograde viewing, has revealed a significant improvement in the detection of adenoma and polyp. However, the Third Eye Retroscope was limited by its deployment through the working channel of the scope. Recently, the Third Eye Panoramic cap, which was designed to overcome the limitation of the Third Eye Retroscope, was introduced. In the future, this would be needed to evaluate the effectiveness, efficiency and safety for these new colonoscopies and accessories.
References
1. Rex DK, Cutler CS, Lemmel GT, et al. Colonoscopic miss rates of adenomas determined by back-to-back colonoscopies. Gastroenterology. 1997; 112:24–28.
2. Deenadayalu VP, Chadalawada V, Rex DK. 170 degrees wide-angle colonoscope: effect on efficiency and miss rates. Am J Gastroenterol. 2004; 99:2138–2142.
3. Pellisé M, Fernández-Esparrach G, Cárdenas A, et al. Impact of wide-angle, high-definition endoscopy in the diagnosis of colorectal neoplasia: a randomized controlled trial. Gastroenterology. 2008; 135:1062–1068.
4. Uraoka T, Tanaka S, Oka S, Matsuda T, Saito Y, Moriyama T, et al. Feasibility of a novel colonoscope with extra-wide angle of view: a clinical study. Endoscopy. 2015; 47:444–448.
5. Gralnek IM, Carr-Locke DL, Segol O, et al. Comparison of standard forward-viewing mode versus ultrawide-viewing mode of a novel colonoscopy platform: a prospective, multicenter study in the detection of simulated polyps in an in vitro colon model (with video). Gastrointest Endosc. 2013; 77:472–479.
6. Gralnek IM, Segol O, Suissa A, et al. A prospective cohort study evaluating a novel colonoscopy platform featuring full-spectrum endoscopy. Endoscopy. 2013; 45:697–702.
7. Gralnek IM, Siersema PD, Halpern Z, Segol O, Melhem A, Suissa A, et al. Standard forward-viewing colonoscopy versus full-spectrum endoscopy: an international, multicentre, randomised, tandem colonoscopy trial. Lancet Oncol. 2014; 15:353–360.
8. Song JY, Cho YH, Kim MA, Kim JA, Lee CT, Lee MS. Feasibility of full-spectrum endoscopy: Korea's first full-spectrum endoscopy colonoscopic trial. World J Gastroenterol. 2016; 22:2621–2629.
9. McGill SK, Kothari S, Friedland S, Chen A, Park WG, Banerjee S. Short turn radius colonoscope in an anatomical model: retro-flexed withdrawal and detection of hidden polyps. World J Gastroenterol. 2015; 21:593–599.
10. Pohl H, Bensen SP, Toor A, et al. Cap-assisted colonoscopy and detection of Adenomatous Polyps (CAP) study: a randomized trial. Endoscopy. 2015; 47:891–897.
11. Kondo S, Yamaji Y, Watabe H, et al. A randomized controlled trial evaluating the usefulness of a transparent hood attached to the tip of the colonoscope. Am J Gastroenterol. 2007; 102:75–81.
12. Rastogi A, Bansal A, Rao DS, et al. Higher adenoma detection rates with cap-assisted colonoscopy: a randomised controlled trial. Gut. 2012; 61:402–408.
13. Harada Y, Hirasawa D, Fujita N, et al. Impact of a transparent hood on the performance of total colonoscopy: a randomized controlled trial. Gastrointest Endosc. 2009; 69:637–644.
14. de Wijkerslooth TR, Stoop EM, Bossuyt PM, et al. Adenoma detection with cap-assisted colonoscopy versus regular colonoscopy: a randomised controlled trial. Gut. 2012; 61:1426–1434.
15. Ng SC, Tsoi KK, Hirai HW, et al. The efficacy of cap-assisted colonoscopy in polyp detection and cecal intubation: a metaanalysis of randomized controlled trials. Am J Gastroenterol. 2012; 107:1165–1173.
16. Tsiamoulos ZP, Saunders BP. A new accessory, endoscopic cuff, improves colonoscopic access for complex polyp resection and scar assessment in the sigmoid colon (with video). Gastrointest Endosc. 2012; 76:1242–1245.
17. Lenze F, Beyna T, Lenz P, Heinzow HS, Hengst K, Ullerich H. Endocuff-assisted colonoscopy: a new accessory to improve adenoma detection rate? Technical aspects and first clinical experiences. Endoscopy. 2014; 46:610–614.
18. Floer M, Biecker E, Fitzlaff R, et al. Higher adenoma detection rates with endocuff-assisted colonoscopy – a randomized controlled multicenter trial. PLoS One. 2014; 9:e114267.
19. Biecker E, Floer M, Heinecke A, et al. Novel endocuff-assisted colonoscopy significantly increases the polyp detection rate: a randomized controlled trial. J Clin Gastroenterol. 2015; 49:413–418.
20. Dik VK, Gralnek IM, Segol O, et al. Multicenter, randomized, tandem evaluation of EndoRings colonoscopy–results of the CLEVER study. Endoscopy. 2015; 47:1151–1158.
21. Hasan N, Gross SA, Gralnek IM, Pochapin M, Kiesslich R, Halpern Z. A novel balloon colonoscope detects significantly more simulated polyps than a standard colonoscope in a colon model. Gastrointest Endosc. 2014; 80:1135–1140.
22. Gralnek IM, Suissa A, Domanov S. Safety and efficacy of a novel balloon colonoscope: a prospective cohort study. Endoscopy. 2014; 46:883–887.
23. Halpern Z, Gross SA, Gralnek IM, et al. Comparison of adenoma detection and miss rates between a novel balloon colonoscope and standard colonoscopy: a randomized tandem study. Endoscopy. 2015; 47:238–244.
24. Triadafilopoulos G, Watts HD, Higgins J, Van Dam J. A novel retrograde-viewing auxiliary imaging device (Third Eye Retroscope) improves the detection of simulated polyps in anatomic models of the colon. Gastrointest Endosc. 2007; 65:139–144.
25. Triadafilopoulos G, Li J. A pilot study to assess the safety and efficacy of the Third Eye retrograde auxiliary imaging system during colonoscopy. Endoscopy. 2008; 40:478–482.
26. DeMarco DC, Odstrcil E, Lara LF, et al. Impact of experience with a retrograde-viewing device on adenoma detection rates and withdrawal times during colonoscopy: the Third Eye Retroscope study group. Gastrointest Endosc. 2010; 71:542–550.
27. Waye JD, Heigh RI, Fleischer DE, et al. A retrograde-viewing device improves detection of adenomas in the colon: a prospective efficacy evaluation (with videos). Gastrointest Endosc. 2010; 71:551–556.
28. Leufkens AM, DeMarco DC, Rastogi A, et al. Effect of a retrograde-viewing device on adenoma detection rate during colonoscopy: the TERRACE study. Gastrointest Endosc. 2011; 73:480–489.
29. Rubin M, Lurie L, Bose K, Kim SH. Expanding the view of a standard colonoscope with the Third Eye Panoramic cap. World J Gastroenterol. 2015; 21:10683–10687.