Post Market Evaluation of Aer-O-Scope Visualization

This will be a prospective multi-center, multi-national comparative non-blinded clinical investigation. Each subject will undergo back-to-back tandem colonoscopies with the Aer-O-Scope Colonoscope System and a conventional colonoscope since this is a tandem colonoscopy study, each subject will serve as their own control. The 1st procedure will be randomized, half to Aer-O-Scope Colonoscope System and half to conventional colonoscope. The same investigator will perform both procedures on each subject. All pathologies found will be either removed or tattooed. Unmarked pathologies found on second pass will represent those missed during the 1st pass, thus making the subject and the control one and the same. Tattooed pathologies that can be removed endoscopically will be removed in an additional colonoscopy. This may occur if a large polyp cannot be removed for any reason with the Aer-O-Scope, but can be removed with conventional colonoscopy.

Subjects will be randomized in blocks of twenty (20) for either Aer-O-Scope or conventional colonoscopy as the first procedure. Physicians will be notified of the procedural order immediately prior to first colonoscopy. Up to the first ten (10) cases for each physician (system operation training cases) will all begin with the Aer-O-Scope colonoscopy as the first procedure.

The primary endpoint of AMR was chosen as this measure appears to be related to the performance of colonoscopy and reduction in colorectal cancer incidence. During the course of the last decade, several major visualizations studies have been performed and it has become common practice to use the "second-pass" method for measuring colonoscopy visualization methods, iii, iv. In the "second-pass" method, during the course of the first colonoscopy, all visualized lesions are removed (or tattooed in the event that they cannot be removed for any reason.). Any unmarked abnormalities discovered during the second pass colonoscopy are considered to be missed pathologies for the first pass colonoscopy.

All endpoints related to timing will be measured using a stopwatch and overall time stamp from the Aer-O-Scope or conventional colonoscope. Time to perform therapeutic interventions with Aer-O-Scope as well as a description of said interventions will also be recorded. The same instruments will be used to measure all procedures and will be calibrated as dictated by the manufacturer.

All equipment used during the course of this clinical investigation will undergo calibration and testing as per the manufacturing instructions. The Aer-O-Scope Colonoscope System has an automated calibration system and diagnostic test that run daily. Conventional colonoscopes will be maintained as per hospital/manufacturer protocol.

Recruited subjects who are withdrawn as a result of poor bowel prep or any other medical determination leading to the inability to undergo colonoscopy and/or tandem colonoscopy will be replaced. A poor prep is defined as having a score of score of 0 or 1 in the Boston Bowel Preparation Scale (BBPS). The BBPS scores are as follows:

0 = Unprepared colon segment with mucosa not seen due to solid stool that cannot be cleared.

1. = Portion of mucosa of the colon segment seen, but other areas of the colon segment not well seen due to staining, residual stool and/or opaque liquid.
2. = Minor amount of residual staining, small fragments of stool and/or opaque liquid, but mucosa of colon segment seen well.
3. = Entire mucosa of colon segment seen well with no residual staining, small fragments of stool or opaque liquid.

Any subject withdrawn as a result of physician discretion due to concomitant medical issues will be withdrawn prior to the actual colonoscopic procedures. Patients with a large polyp (\>20mm) removed during the first pass with a conventional colonoscope will be withdrawn. Patients who receive treatment during the first pass with clips (no other option available) will be withdrawn.

Coagulation therapy should be performed either with Argon Plasma Coagulation (APC) or another cautery tool or contact thermal device as per clinical protocol. For the purpose of this clinical investigation, clips should not be used unless there is no alternative. Patients treated with clips prior to their final pass colonoscopy, will be withdrawn from the investigation.

Physicians may also withdraw any patient due to medical causes if deemed appropriate, including patients that have undergone at least one (1) procedure.

Eligibility Criteria:
Inclusion Criteria:

1. Subject is indicated for screening, diagnostic (minor complaints such as rectal bleeding or minor abdominal pain) or surveillance colonoscopy
2. Subject willing to undergo tandem colonoscopies with Aer-O-Scope Colonoscope and a conventional colonoscope (including a single colon preparation bowel cleansing)
3. Subject between the ages of 45 and 75 (patients between the ages of 45 and 50 must have a family history of a first degree relative with onset of colon cancer before the age of 60).
4. Subject is able to understand and willing to sign informed consent form

Exclusion Criteria:

1. Personal history of colorectal neoplasia including familial adenomatous polyposis or hereditary nonpolyposis, colon cancer (HNPCC).
2. Diagnosis of active (flaring) inflammatory bowel disease (active ulcerative colitis or Crohn's colitis), bowel obstruction, or acute diverticulitis, or known severe diverticulosis, fecal incontinence or any known large-bowel disease that would require a predetermined therapeutic colonoscopy (non-screening, non-diagnostic or non-surveillance cases)
3. Severe gastrointestinal tract-related symptoms, or complaints, suggesting performance of a pre-determined therapeutic colonoscopy (non-screening, non-diagnostic or non-surveillance cases)
4. History of colonic resection
5. Clinically significant cardiovascular or pulmonary disease.
6. Cancer or other life threatening disease or significant chronic condition that puts the subject at risk.
7. Blood-clotting disorders and/or current anticoagulant therapy (Subjects taking up to 100mg aspirin for prophylactic treatment are acceptable for this study)
8. Pregnancy
9. Previous radiation therapy to the abdomen
10. Morbid Obesity (BMI \> 40 kg/m2)
11. Drug abuse or alcoholism
12. Subject is bed-ridden and/or unable to adequately communicate
13. Subject is under custodial care
14. Subject has a history of psychiatric disorders which would prevent compliance with study instructions
15. Participation in a clinical study within the previous 30 days