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PWE-019 Polyp detection rate. does length matter?
  1. J Segal,
  2. P Mills,
  3. SM Greenfield
  1. Gastroenterology, Lister Hospital, Stevenage, UK


Introduction Polyp detection is a vital for any colonoscopist to reduce colon cancer risk. The USA National Polyp Study reported that endoscopic removal of all adenomas was associated with a 76–90% decrease in cancer incidence compared to 3 separate historic reference groups. Polyp detection rate (PDR) depends on factors such as withdrawal time and quality of bowel prep. Our study assessed whether the physical distance of the endoscopist to the live screen had a significant relationship to the PDR, the latter being a surrogate marker for adenoma detection rate.

Method Using endoscopy reports we retrospectively compared the PDR at colonoscopy and flexible sigmoidoscopy in 2 separate hospitals each with 2 endoscopy rooms over a 12 month period. Endoscopists work cross site and across all rooms. The distances between the endoscopist and the screen were measured. In hospital A there is a marked difference in distance between the endoscopist to screen when comparing the two endoscopy rooms. In hospital B the endoscopist to screen distances are identical in the 2 rooms and we used this as a control group. A paired t test was used for statistical analysis Significance was set at p < 0.01

Results In hospital A, 1,086 lower GI examinations were done in room 1 with a PDR of 35.3% with endoscopist to screen measurement at 219 cm. In room 2, 1,040 lower GI exams were done with a PDR of 45.4% and an endoscopist to screen measurement of 147 cm. The PDR was significantly higher in the room where the monitor was 72 cm closer to the endoscopist (p < 0.00001). In hospital B, there were no significant differences in PDR detected at colonoscopy between the two endoscopy rooms (40% v 34.2%, monitor distance 190 cm).

Conclusion Both JAG and the World Endoscopy Organisation have issued guidelines on the construction of an endoscopy unit. There is limited information on the significances of distances between an endoscopist and the screen. Our study highlights that this may be a factor to consider when designing an endoscopy room. The room with the closest screen had the highest PDR at colonoscopy. Our work suggests that the closer the endoscopist is to the screen the higher the polyp detection rate. More work may determine the optimum endoscopist to screen distance for PDR.

Disclosure of interest None Declared.


  1. Winawer SJ, Zauber AG, Ho MN, et al . Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med 1993;329:1977

  2. Mulder CJ, Jacobs, MAJM, et al. Guidelines for designing a digestive disease endoscopy.unit: report of the world endoscopy organization. Dig Endosc.2013;25:365–375


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