Posted on 21 August 2015
We asked Dr Naayil Rajabally, a gastroenterologist at Mediclinic Constantiaberg, to answer some FAQs on colonoscopies.
What is a colonoscopy?
It is an examination of the colon – the large intestine – carried out by a doctor trained in endoscopy, usually a gastroenterologist. It is a very accurate way of looking at the lining of the intestine to establish whether disease is present. The instrument used is a fibre-optic tube called a colonoscope that directs light onto the lining of the bowel, and a camera sends pictures to a screen to be analysed by the endoscopist. A colonoscopy also allows biopsies (small pieces of tissue) to be taken for examination by a pathologist to confirm the presence of disease. In experienced hands, a colonoscopy is not a painful procedure. In addition, by having an anaesthetist provide deep sedation to the patient, the procedure is extremely well tolerated. While the anaesthetist monitors the patient’s vital functions, the gastroenterologist can dedicate his/her entire focus to the bowel.
Why would I need a colonoscopy?
Colonoscopies are performed in both symptomatic and asymptomatic patients. In the first scenario, the symptoms that would warrant a colonoscopy include rectal bleeding, chronic diarrhoea, a change in bowel patterns, unexplained weight loss and unexplained iron deficiency. In the asymptomatic patient, a colonoscopy is done for screening for colon cancer or colon polyps in a patient over the age of 50, or earlier if the patient has a family history of colon cancer or colon polyps.
What is a colon polyp?
A polyp is an abnormal growth of tissue that forms in the bowel lining. Some polyps are attached to the intestinal wall by a stalk and look like a mushroom, whereas others are flat without a stalk. If a polyp is found, it is usually removed by the gastroenterologist as it may grow further and cause problems later. The removal is done by passing special forceps, wire snare or a loop through the colonoscope and removing the polyp from the bowel wall, sometimes by means of an electric current. Taking biopsies or removing polyps causes no discomfort.
How do I prep for a colonoscopy?
Preparation is vital for an optimal examination and involves the cleansing of the colon by taking a colon prep solution the day before the procedure. There are two basic prep solutions available – low volume and high volume. Some gastroenterologists prefer split prep compared to continuous prep. What is important is that you follow your doctor’s instructions carefully and drink plenty of liquids on the prep day to avoid dehydration and ensure a clean colon.
How has the equipment changed?
Technology has improved over the years. The gastroenterologist used to look down through an eye piece to see inside the colon. Now we’re able to view it on high-definition screens, and with the latest available scopes the picture quality is amazing. It’s also important to document that the end of the colon has been reached, the quality of the patient’s prep and whether polyps were detected and removed. The technology now allows the gastroenterologist to do all of the above.