A colonoscopy with chromoendoscopy is a procedure where a physician uses a flexible, thin tube with a camera and light source to examine the inside of the rectum and colon. During the colonoscopy procedure, dye is sprayed directly on the colorectal mucosa.
Chromoendoscopy, performed by spraying dye on the colorectal mucosa during colonoscopy, has been reported to improve detection of flat dysplasia in patients with Ulcerative colitis, Crohn’s colitis, and of flat adenomas in screening and high-risk populations.
The colon must be completely clean to achieve accurate results from a colonoscopy. Patients will usually be given a special cleansing solution to drink before the exam, or may be asked to consume only a clear liquid diet with laxatives or enemas. Most medications can still be taken, although some such as aspirin or blood thinners may require special instructions. Your doctor will instruct you on how to prepare.
Before the colonoscopy, an IV is inserted a short-acting anesthetic is given to make the patient relaxed and sleepy. The heart, blood pressure and oxygenation of the blood are monitored throughout the procedure. During the colonoscopy, the patient lies on their left side or back as the colonoscope is slowly inserted. It reaches all the way to the tip of the colon and examines the lining as it passes in and out. Dye is sprayed directly on the colorectal mucosa during the procedure. The procedure takes about 15-20 minutes on average. Biopsies and removal of polyps are all performed during the procedure.
After the procedure, patients will be kept under observation for about an hour, until the medication wears off. Reflexes and judgment may be impaired for the rest of the day, so we advise against driving and doing any strenuous activities that day. Some cramping or bloating may be experienced, but should be relieved quickly. Eating and other normal activities can resume immediately.
Overall, the risks associated with colonoscopy with chromoendoscopy are low. Bleeding can occur from a biopsy or removal of a polyp or growth from the colonoscopy, but such bleeding often stops on its own or can be controlled through the colonoscopy. Perforation (a hole or a deep tear in the lining of the colon or rectum) may require surgery, but this is an uncommon complication. Injury to other organs such as the spleen can occur, but is very rare. Other risks involve complications related to the anesthetics and sedatives, (breathing difficulties, aspiration) or complications related to heart and lung disease.
