Use of endoscopic distal attachment cap to enhance image stabilization in probe-based confocal laser endomicroscopy in colorectal lesions^[*]

Background and study aims: Colorectal cancer can be prevented through the use of colonoscopy with polypectomy. Most colon polyps are benign or low grade adenomas. However, currently all lesions need histopathologic analysis, which increases diagnostic costs and delays the final diagnosis. Confocal laser endomicroscopy (CLE) is a new technology that enables real-time endomicroscopy. However, there are challenges to maintaining a stable image with currently available systems. We conducted a small study to obtain a preliminary assessment of whether the use of an endoscopic distal attachment cap may enhance image quality of CLE in comparison with images obtained with free-hand acquisition.

Patients and methods: Forty outpatients underwent colonoscopy for evaluation of colon polyps in a single academic medical center. Patients were assigned randomly to 1 of 2 study arms on the basis of whether an endoscopic distal attachment cap was used (n = 21, Cap Used) or not used (n = 19, No Cap) in the procedure. The quality of confocal images and probe stabilization was summarized.

Results: A total of 81 polyps were identified. The proportion of polyps with images of high quality was 74 % (28/38) in the Cap Used group and 79 % (30/38) in the No Cap arm. Image stability was also similar with and without a cap. Diagnostic accuracy was estimated to be slightly higher in the Cap Used group for probe-based confocal laser endomicroscopy (pCLE; 78 % vs 70 %). This was also true for white-light and narrow-band imaging.

Conclusions: This preliminary study did not yield any evidence to support that the use of an endoscopic distal attachment cap improves the quality of images obtained during CLE.

^* This sudy was presented as a poster abstract at DDW 2013

^** Drs. Ussui and Xu: These authors contributed equally.

• References

• 1 Rex DK, Kahi C, O'Brien M et al. The American Society for Gastrointestinal Endoscopy PIVI (Preservation and Incorporation of Valuable Endoscopic Innovations) on real-time endoscopic assessment of the histology of diminutive colorectal polyps. Gastrointest Endosc 2011; 73: 419-422
• 2 Levin B, Lieberman DA, McFarland B et al. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. Gastroenterology 2008; 134: 1570-1595
• 3 Odom SR, Duffy SD, Barone JE et al. The rate of adenocarcinoma in endoscopically removed colorectal polyps. Am Surg 2005; 71: 1024-1026
• 4 Seeff LC, Richards TB, Shapiro JA et al. How many endoscopies are performed for colorectal cancer screening? Results from CDC's survey of endoscopic capacity. . Gastroenterology 2004; 127: 1670­-1677
• 5 Wallace MB, Kiesslich R. Advances in endoscopic imaging of colorectal neoplasia. Gastroenterology 2010; 138: 2140-2150
• 6 Ussui VM, Wallace MB. Confocal endomicroscopy of colorectal polyps. Gastroenterol Res Pract 2012; DOI: 10.1155/2012/545679.
• 7 Wallace M, Lauwers GY, Chen Y et al. Miami classification for probe-based confocal laser endomicroscopy. Endoscopy 2011; 43: 882-891
• 8 Parra-Blanco A, Matsuda T, Fujii T et al. Diagnostic advantage of optical vs electronic magnification for the diagnosis of colonic polyps. Gastrointest Endosc 2008; AB126. 67 http://www.giejournal.org/article/S0016-5107(08)00626-3/abstract
• 9 Wang AY, Shami VM, Kahaleh M et al. Presence of meshed capillary vessels on narrow-band imaging effectively identifies colorectal neoplasia without optical magnification: a North American validation of the Japanese experience. Gastrointest Endosc 2009; 69 AB297. http://www.giejournal.org/article/S0016-5107(09)01312-1/abstract
• 10 Rex DK. Narrow-band imaging without optical magnification for histologic analysis of colorectal polyps. Gastroenterology 2009; 136: 1174­-1181
• 11 Buchner AM, Shahid MW, Heckman MG et al. Comparison of probe-based confocal laser endomicroscopy with virtual chromoendoscopy for classification of colon polyps. Gastroenterology 2010; 138: 834-842
• 12 Wells AP, Wakely L, Birchall W et al. In vivo fibreoptic confocal imaging (FOCI) of the human ocular surface. J Anat 2006; 208: 197-203
• 13 Kiesslich R, Burg J, Vieth M et al. Confocal laser endoscopy for diagnosing intraepithelial neoplasias and colorectal cancer in vivo. Gastroenterology 2004; 127: 706-713
• 14 Latt WT, Newton RC, Visentini-Scarzanella M et al. A hand-held instrument to maintain steady tissue contact during probe-based confocal laser endomicroscopy. IEEE Trans Biomed Eng 2011; 58: 2694-2703
• 15 Shahid MW, Buchner AM, Raimondo M et al. Accuracy of real-time vs. blinded offline diagnosis of neoplastic colorectal polyps using probe-based confocal laser endomicroscopy: a pilot study. Endoscopy 2012; 44: 343-348