Combined Forward and Retroflexion Withdrawal in the Detection of Polyps and Adenoma During Colonoscopy

NCT03901651 | Completed DMC

• 1 other identifier: RV03-2019
• Study Type: interventional
• Target: 203
• Locations: 1 country
• Sites: 1

Brief Summary

Colonoscopy is the standard of care for the detection of colorectal polyps and adenoma, and colorectal cancer detection. Despite a meticulous evaluation of the colonic mucosa during colonoscopy, a substantial number of colorectal polyps might be missed and colorectal cancer might not be prevented. Previous studies described a 12-28% of miss-rate for all polyps, a 31% for hyperplastic polyps and 6-27% for adenomas, with a higher miss rate noted for smaller polyps. The lesion missing rate depends on several factors, such as the location on difficult areas to be evaluated with conventional colonoscopes (the proximal side of the ileocecal valve, haustral folds, flexures or rectal valves), a flat shape, an inadequate bowel preparation and inadequate endoscopy technique, a time-limited colonoscope withdrawal. If the standard 140º angle of view colonoscope is used approximately 13% of the colonic surface is unevaluated. The incorporation of colonoscopes with a 170-degree wide angled could improve adenoma detection rate. The introduction of high definition (HD) colonoscopes and visual image enhancement technologies, such as narrow band imaging (NBI, Olympus America, Center Valley, PA), I-SCAN™ (Pentax Medical, Montvale, NJ) and Fuji Intelligent Chromo-Endoscopy (FICE™, Fujinon Endoscopy, Wayne, NJ) have improved the lesion characterization; however, several studies have failed to prove an increase in the adenoma detection rates. The Third Eye Retroscope (Avantis Medical Systems, Sunnyvale, CA) is a disposable retrograde viewing device advanced through the accessory channel of a standard colonoscope. It allows retrograde viewing behind colonic folds and flexures simultaneously with the forward view of the colon. Although it shows an increase in the adenoma detection rate by 11%-25%, it has many disadvantages. First, it requires a separate processor and the device is disposable, increasing the cost of the procedure. Second, it occupies the working channel of the colonoscope, limiting the ability to suction. Third, if a polyp is detected, the viewing device has to be removed in order to perform the polypectomy. Fourth, the optic is not high definition and finally, the endoscopist has to get used to visualizing and processing two simultaneous video streams from the colonoscopy and from the retroscope device.

Conditions

Colonic Polyp; Colonic Neoplasms; Colonic Adenoma

Keywords

colonic polyps

Outcome Measures

Primary Outcomes (2)

• Polyp detection rate with standard colonoscope and the Retroview colonoscope

  Polyps found during standard colonoscopy/total of polyps found x 100; polyps found with the Retroview scope/total of polyps found x100. The total of polyps found will be defined by the combination of both methods

  23 months

• Adenoma detection rate with standard colonoscope and retroview colonoscope.

  Adenomas found during standard colonoscopy/total of adenomas found x 100; adenomas found with the Retroview scope/total of adenomas found x100. The total of adenomas found will be defined by the combination of both methods

  23 months

Secondary Outcomes (3)

• Lesion miss rate with the standard colonoscope and Retroview scope

  23 months

• Number of lesions (adenomas and polyps) detected with the standard colonoscope and Retroview colonoscope.

  23 months

• Size of lesions (adenomas and polyps) detected with the standard colonoscope and Retroview colonoscope.

  23 months

Study Arms (2)

Standard colonoscopy

ACTIVE COMPARATOR

Patients submitted for screening, surveillance or diagnostic colonoscopy. A standard colonoscopy with forwarding viewing withdrawal technique. An HD colonoscope with I-scan technology will be used by one expert endoscopist. Each polyp and adenoma will be recorded, including the size and location. Polyps will be removed before the second procedure.

Diagnostic Test: Colonoscopy with standard colonoscope and forward withdrawal technique

Retroview colonoscopy

EXPERIMENTAL

The same group of patients. A second colonoscopy using a combined forward and retroflexed evaluation of the colonic mucosa. using the Retroview™ scope. The operator will be blind to the first colonoscopy findings. The operator will record the polyps and adenoma encountered, describing the size and location.

Diagnostic Test: Colonoscopy with Retroview scope combing forward and retroflexed withdrawal technique

Interventions

Colonoscopy with Retroview scope combing forward and retroflexed withdrawal technique DIAGNOSTIC_TEST

Colonoscopy using a combined forward and retroflexed evaluation of the colonic mucosa. using the Retroview™ scope. The operator will be blind to the standard colonoscopy findings. The operator will record the polyps and adenoma encountered, describing the size and location.

Retroview colonoscopy

Colonoscopy with standard colonoscope and forward withdrawal technique DIAGNOSTIC_TEST

A standard colonoscopy with forwarding viewing withdrawal technique. An HD colonoscope with I-scan technology will be used by one expert endoscopist. Each polyp and adenoma will be recorded, including the size and location.

Standard colonoscopy

Eligibility Criteria

• Age: 45 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients capable of providing written consent
• Colonoscopy indicated for colorectal cancer screening or surveillance
• Patients submitted for polypectomy
• Colonoscopy indicated for diagnostic purposes: anemia, abdominal pain, constipation, alteration of bowel habits.

You may not qualify if:

• Patients under 45 years and over 80 years of age.
• Pregnancy and/or nursing.
• Patients with past-medical history of cardiac, renal, hepatic or severe metabolic diseases
• Unable to tolerate sedation
• Severe uncontrolled coagulopathy
• Past surgical history of colonic resection, ileostomy or colostomy.
• Previous abdominal or pelvic radiation therapy.
• Patients with inflammatory bowel disease, polyposis syndrome or acute diverticulitis.
• Patients with high suspicion of colonic obstruction or history of prior obstruction.
• Patients with gastrointestinal bleeding.
• Inadequate bowel preparation. The bowel preparation will be evaluated using the Boston Bowel Preparation Scale. Patients with \< 2 points in at least one of the three segments of the colon will be excluded.
• Patients who after the beginning of the colonoscopy have to be suspended due to the inability to reach into the cecum because of unfavorable anatomy or impassable tumors/stenosis.

Sponsors & Collaborators

• Instituto Ecuatoriano de Enfermedades Digestivas: lead

Study Sites (1)

Ecuadorian Institute of Digestive Diseases

Guayaquil, Guayas, 090505, Ecuador

Location

MeSH Terms

Conditions

Colonic Polyps; Colonic Neoplasms

Interventions

Colonoscopy

Condition Hierarchy (Ancestors)

Intestinal Polyps; Polyps; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Intestinal Diseases

Intervention Hierarchy (Ancestors)

Endoscopy, Gastrointestinal; Endoscopy, Digestive System; Diagnostic Techniques, Digestive System; Diagnostic Techniques and Procedures; Diagnosis; Endoscopy; Diagnostic Techniques, Surgical; Digestive System Surgical Procedures; Surgical Procedures, Operative; Minimally Invasive Surgical Procedures

Study Officials

• Carlos Robles-Medranda, MC

  Instituto Ecuatoriano de Enfermedades Digestivas

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Patients submitted for screening, surveillance or diagnostic colonoscopy. First, a colonoscopy using a HD standard colonoscope using a forward viewing withdrawal technique. Then, a second colonoscopy using the Retroview colonoscope combining forward and retroflexed evaluation of the colon will be performed in the same patient.

Study Record Dates

• First Submitted: March 25, 2019
• First Posted: April 3, 2019
• Study Start: January 2, 2019
• Primary Completion: December 1, 2020
• Study Completion: January 1, 2021
• Last Updated: June 2, 2021

Record last verified: 2021-06

Data Sharing

• IPD Sharing: Will not share

Locations

EC (1)