I-Scan Vs High Definition White Light (Main Study)

The purpose of this 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: Adenoma Detection Rate (ADR - No. of colonoscopies at which one or more histologically confirmed adenomas were found divided by the total no. of colonoscopies performed in the same time period) in the right colon using High Definition White Light Colonoscopy Versus I-Scan enhanced Colonoscopy. Secondary Outcomes: * Adenoma Detection Rate (ADR) of High Definition White Light Colonoscopy Versus I-Scan colonoscopy through out the entire colon. * Adenoma Detection Rate (ADR) in the right colon during the "Second look", irrespective of imaging modality. * Polyp Detection Rate (PDR - No. of colonoscopies at which one or more polyps were found(regardless of the histological type) divided by the total no. of colonoscopies performed in the Same time period) for each arm of the study in Right colon and throughout the entire colon. * Mean number of adenomas per procedure for each arm of the study in right colon and throughout the entire colon. * Mean number of polyps per procedure for each arm of the study in right colon and throughout the entire colon. * Number of neoplastic lesions for each arm of the study in the right colon and throughout the entire colon and number of neoplastic lesions missed on 1st pass of right colon. * Proportion of patients with diminutive lesions (\< 5 mm) in each arm of the study * Proportion of patients with Flat lesions (height \< 1/2 diameter) in each arm of the study * Proportion of patients with Sessile Serrated Adenoma in each arm of the study * Proportion of patients with invasive cancer in each arm of the study * Presence or absence of learning effect while using this technology given that use of I-Scan may train the human eye to better identify adenomas even without image enhancement.

Sex

All

Minimum age

18 Years

Maximum age

74 Years

Inclusion Criteria:

* All increased risk patients (Patients with family history or personal history of colon polyps or colon cancer and FOBT positive) referred for a screening colonoscopy at the Forzani and MacPhail Colon Cancer Screening Centre will be considered for enrollment.

Exclusion Criteria:

* Average Risk patients
* Previous colon surgery
* Hereditary Polyposis Syndromes
* Suspected polyps or CRC before colonoscopy that have been suggested by another modality (Barium Enema, Virtual Colonoscopy, Flexible Sigmoidoscopy)