Rectosigmoidoscopy
What is a rectosigmoidoscopy?
A rectosigmoidoscopy is a test to examine the rectum and the lining of your sigmoid colon - the lower part of your large intestine. It is carried out to see if there’s any potential abnormal growths of tissue, also known as polyps, or to see if there is a tumour in its early stage.
Using this test, the doctor can verify and (if need be) remove polyps which could grow to become tumours at the same. It has been estimated that rectosigmoidoscopy can lower your chances of developing large intestine cancer by 45%.
What is it for?
You may need to have a rectosigmoidoscopy if you are experiencing rectal bleeding or blood in your stool, changes to or irregular bowel habits, persistent abdominal pain, and persistent diarrhoea.
What does it involve?
Rectosigmoidoscopy involves passing a very small, flexible endoscope (about 1 cm thick) through the anus. The endoscope has a camera and a light at its end. The probe allows the gastroenterologist to accurately examine the internal lining of the intestine. Your doctor will be able to see if there are any polyps, bowel inflammation, or haemorrhoids, and take a small tissue sample for further analysis. The test takes around 10 minutes in total.
How can I prepare for it?
Preparing for this procedure is quite simple. To make sure the doctor has a clear view of your colon, it must be completely empty, so that any polyps or lesions will be clearly visible. You generally have an enema to allow a clear view of the lower bowel which can be administered at home before the test, or more commonly, upon arrival at the hospital. There is no need to make any dietary changes before.
What does it feel like during the procedure?
Rectosigmoidoscopy doesn’t usually require any anaesthetic, as it will only cause a mild discomfort. You may be prone to pain due to some potential anatomical peculiarities, such as a very long intestine, scarring due to previous surgery or inguinal hernia. In this case, your doctor will give you something to relieve the pain.
Once the test is over, you can go back home without any problems. There may be some side effects, such as some bloating or abdominal cramps. However, these symptoms should not last more than a couple of hours. Serious complications from rectosigmoidoscopy are extremely rare (less than 1%) and may involve bleeding. Very rarely, perforation caused by the probe may occur.
What would a “bad” result mean?
At the end of the test, your doctor will be able to give you a result. If nothing suspicious is found, you won’t have to repeat the exam.
However, if the doctor found polyps, they will either be removed during the procedure, or a histological examination will be carried out on a tissue sample collected during the exam. After a couple of weeks, your results will be ready. If the doctor needs to know more, you may be asked to undergo a colonoscopy.