title: Optical colonoscopy and virtual colonoscopy numbers after initiation of a CT colonography program: long term data.
abstract: OBJECTIVE
  The effect of CT colonography (CTC) screening on colonoscopy is unknown. The objective of this study is to determine the effect of a CTC screening program on the number of screening, therapeutic and total colonoscopies performed.
  
  
  METHODS
  We compared the quarterly mean numbers of colonoscopic examinations performed for 50-79 year olds undergoing colorectal cancer screening in 2003, before initiation of a CTC program, to 2011, seven years after the CTC program began at our academic tertiary care facility.
  
  
  RESULTS
  The CTC program began in 2004 with a peak number of 387 CTC examinations performed in the 3rd quarter of 2005 and 275 examinations in the final quarter of 2011. Screening colonoscopies increased from 555 mean/quarter in 2003 to 1460 in 2011 (P < 0.001). The mean/quarter number of total colonoscopies performed increased from 1104 in 2003 to 2382 in 2011 (P < 0.001). The number of overall colon cancer screening examinations (Colonoscopy + CTC) increased from 555/quarter in 2003 to 1736 in 2011 (P < 0.001).
  
  
  CONCLUSIONS
  Since the initiation of CTC screening at our institution, the overall number of total colorectal cancer screening examinations (CTC + colonoscopy) has greatly increased. The initiation of a CTC screening program did not lead to a reduction in the number of colonoscopic examinations performed. Conversely, a significant increase in the number of screening and total colonoscopies completed was observed.
authors.affiliation: Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792, USA. mb4@medicine.wisc.edu
authors.forename: Mark
authors.initials: M
authors.lastname: Benson
authors.forename: Jeff
authors.initials: J
authors.lastname: Pier
authors.forename: Sally
authors.initials: S
authors.lastname: Kraft
authors.forename: David
authors.initials: D
authors.lastname: Kim
authors.forename: Perry
authors.initials: P
authors.lastname: Pickhardt
authors.forename: Jennifer
authors.initials: J
authors.lastname: Weiss
authors.forename: Deepak
authors.initials: D
authors.lastname: Gopal
authors.forename: Mark
authors.initials: M
authors.lastname: Reichelderfer
authors.forename: Patrick
authors.initials: P
authors.lastname: Pfau
mesh_terms: D000368:Aged; D023881:Colonography, Computed Tomographic / Q000706:statistics & numerical data*; D003113:Colonoscopy / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D055088:Early Detection of Cancer / Q000379:methods / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D014922:Wisconsin