I-Scan Versus High-definition White Light
Condition: Colorectal Cancer
MeSH terms: Colorectal Neoplasms
Study type: Interventional

Summary: 
      The purpose of the study is to assess whether the use of I-scan during colonoscopy leads to
      an increased yield of adenomas in the colon among a population at increased risk for CRC.

      Primary Outcome:

      To estimate the mean number of adenomas per colonoscopy for both high definition white light
      colonoscopy and I-scan enhanced colonoscopy

      Secondary Outcomes:

        1. To estimate the recruitment rate

        2. Number of adenomas detected in the right colon during the second look
    

Detailed description: 
      Colorectal Cancer is the third most common cause of cancer in Canada with an estimated
      lifetime risk of developing the disease of 6-7%. Each year there are approximately 21,000 new
      cases and 9,100 deaths attributable to this disease. Colonoscopy is one of several methods
      recommended for CRC screening by current guidelines. While colonoscopy is the most invasive,
      it offers high diagnostic accuracy and ability for therapy (biopsy and removal of adenomas)
      compared to other modalities. The emerging evidence regarding missed neoplastic lesions with
      colonoscopy has resulted in quality initiatives designed to improve colonoscopy performance.
      I-Scan (Pentax, Montvale, NJ) is a new method that uses post processing computer algorithms
      to revise the standard white light to highlight pit patterns and vascular surface
      patterns.The relevant I-scan settings in the colon are I-scan 1 and I-scan 2. The primary
      objective of the study is to compare the adenoma detection rate in the right colon using
      High-definition white light colonoscopy versus I-scan enhanced colonoscopy.

      All patients referred for a screening colonoscopy at Forzani and MacPhail Colon Cancer Centre
      will be considered for enrollment.All eligible patients that are not part of another research
      study will be approached for enrollment into the study. During the pre-assessment at the
      clinic a study assistant will contact all the eligible patients to describe the study and
      provide an "Invitation to participate in a Research study" form. The study assistant will
      obtain a final consent if they agree. Those not interested will simply receive the Centre's
      standard protocol. There will be no coercion of any sort. Following Informed Consent,
      treatment allocation through computer generated randomization will be revealed. Patients will
      be allocated to one of the three study arms (HD Colon, I-scan 1 and I-Scan 2). Patients will
      receive a standard bowel preparation: Split dose Polyethylene Glycol (PEG) (2L at noon + 2L
      at 8 PM the day before) for morning procedures or (2L at 8Pm the day before and 2L at five
      hours before the procedure on the day of colonoscopy) for afternoon procedure. certified
      gastroenterologists will perform all of the procedures with the assistance of a nurse. The
      planned "second look" of the right colon will involve withdrawing from the Cecum to Hepatic
      flexure, then re-inserting to Cecum and finally withdrawing through the entire colon. The
      physician performing the procedure will then fill a "Colonoscopy Report Form" including the
      number of polyps detected, size, shape, polypectomy method and cleanliness of the bowel.
    

Intervention name(s): I-Scan 1; HD Colon; I-Scan 2
Intervention type(s): Device; Device; Device
Intervention description(s): I-Scan 1 has contrast enhancement (CE)and surface enhancement (SE). SE mode highlights light-dark contrast thereby providing more mucosal surface detail.CE mode digitally adds blue to darker areas providing detailed imaging of subtle mucosal irregularities.; High definition white light; I-Scan 2 has contrast enhancement (CE), surface enhancement (SE) and tone enhancement (TE). SE mode highlights light-dark contrast thereby providing more mucosal surface detail.CE mode digitally adds blue to darker areas providing detailed imaging of subtle mucosal irregularities.TE provides a uniform colour image and is intended for detailed inspection of distinct lesions.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Screening
Keywords: Colonoscopy; I Scan; High definition white light; Adenomas