title: Efficacy of cap-assisted colonoscopy according to lesion location and endoscopist training level.
abstract: OBJECTIVE
  To evaluate the efficacy of cap-assisted colonoscopy (CAC) for detection of colorectal polyps and adenomas according to the lesion location and endoscopist training level.
  
  
  METHODS
  Patients 20 years or older, who underwent their first screening colonoscopy in a single tertiary center from May 2011 to December 2012 were enrolled in this study. All patients underwent either CAC or standard colonoscopy (SC), and all of the procedures were performed by 11 endoscopists (8 trainees and 3 experts). All procedures were performed with high-definition colonoscopes and narrow band imaging. The eight trainees had experiences of performing 150 to 500 colonoscopies, and the three experts had experiences of performing more than 3000 colonoscopies. A 4-mm-long transparent cap was attached to the end of a colonoscope in the CAC group. We retrospectively evaluated the number of polyps and adenomas, polyp detection rate (PDR), and the number of adenomas and adenoma detection rate (ADR) according to the lesion location and endoscopist training level between CAC and SC. We also evaluated the number of polyps and adenomas according to their size between CAC and SC.
  
  
  RESULTS
  Overall, PDR and ADR using CAC were significantly higher than those using SC for both whole colon (48.5% vs 40.7%, P = 0.012; 35.7% vs 28.3%, P = 0.012) and right-side colon (35.3% vs 26.6%, P = 0.002; 27.0% vs 16.9%, P < 0.001). The number of polyps and adenomas per patient using CAC was significantly higher than that using SC for both the whole colon (1.07 ± 1.59 vs 0.82 ± 1.31, P = 0.008; 0.72 ± 1.32 vs 0.50 ± 1.01, P = 0.003) and right-side colon (0.66 ± 1.18 vs 0.41 ± 0.83, P < 0.001; 0.46 ± 0.97 vs 0.25 ± 0.67, P < 0.001). In the trainee group, the PDR and ADR using CAC were significantly higher than those using SC for both the whole colon (46.7% vs 39.7%, P = 0.040; 33.9% vs 26.0%, P =0.012) and right-side colon (34.2% vs 26.5%, P = 0.015; 25.3% vs 15.9%, P = 0.001). In the expert group, the PDR and ADR using CAC were significantly higher than those using SC only for the right-side colon (42.1% vs 27.0%, P =0.035; 36.8% vs 21.0%, P = 0.020).
  
  
  CONCLUSIONS
  CAC is more effective than SC for detection of colorectal polyps and adenomas, especially when performed by trainees and when the lesions are located in the right-side colon.
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Dong Jun
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Hyung Wook
authors.initials: HW
authors.lastname: Kim
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Su Bum
authors.initials: SB
authors.lastname: Park
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Dae Hwan
authors.initials: DH
authors.lastname: Kang
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Cheol Woong
authors.initials: CW
authors.lastname: Choi
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Joung Boom
authors.initials: JB
authors.lastname: Hong
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Byoung Hoon
authors.initials: BH
authors.lastname: Ji
authors.affiliation: Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea.
authors.forename: Chang Seok
authors.initials: CS
authors.lastname: Lee
mesh_terms: D018256:Adenomatous Polyps / Q000473:pathology*; D000328:Adult; D000368:Aged; D002983:Clinical Competence; D003111:Colonic Polyps / Q000473:pathology*; D020685:Colonoscopes; D003113:Colonoscopy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D062048:Narrow Band Imaging; D011237:Predictive Value of Tests; D056910:Republic of Korea; D012189:Retrospective Studies; D062606:Tertiary Care Centers
keywords: Adenoma; Cap-assisted colonoscopy; Colonic polyps; Colonoscopy; Colorectal neoplasm