When might I need a colonoscopy or an endoscopy and what are they?

You may have heard about these procedures – or even had one yourself – but what exactly are colonoscopies and endoscopies and what are they used for?

A colonoscopy is a type of endoscopy that examines the lower part of your digestive tract, which includes the rectum and large intestine (colon). An endoscopy is a non-surgical procedure to examine the digestive tract. So, in essence, a colonoscopy is through the rectum, and an endoscopy is conducted through the mouth as the entry point.

Colonoscopy

This procedure is carried out using a flexible tube with a camera and light at the end – a colonoscope – which is inserted into the anus through the rectum so it can view the inside of the large bowel or colon. This transmits images to a screen for your physician to view signs of medical conditions. As the tube is flexible it can be turned around curves, allowing it to travel through the length of the colon. It can be up to one centimetre in diameter, so this procedure usually requires twilight sedation to prevent the patient experiencing discomfort and abdominal pain. A gastroenterologist may recommend a colonoscopy to investigate unexplained changes in bowel habits.

Colonoscopy is considered the premium screening method for colorectal cancer, for its ability to view the entire colon and both detect and remove polyps during the same procedure. Colonoscopies allow medical professionals to take a detailed look at the rectum and entire large intestine (colon). Because all colorectal cancer begins as precancerous polyps, removing these polyps during a colonoscopy may prevent this deadly disease.

But before sending you for a colonoscopy, your doctor will most likely recommend a bowel cancer screening test (Faecal Occult Blood Test2 ), which you can carry out in the comfort of your own bathroom and send the sample away to be diagnosed.

Colonoscopy is used

  • to identify the cause of gut-related problems such as abdominal pain or bleeding from the anus
  • after a positive bowel cancer screening test
  • where there is a high risk of illness due to chronic bowel disease or a family history of bowel disease such as bowel cancer
  • to identify the cause of unexplained weight loss
  • following a recommendation from a previous colonoscopy.

Endoscopy procedures

Generally, endoscopy procedures are carried out using an instrument called an endoscope, which is a long, thin, flexible tube with a camera at the end. This provides high[1]quality images of the throat, oesophagus, stomach, rectum and colon. For the instrument to be inserted with the least stress, the patient is usually put under twilight sedation.3

Depending on the condition being investigated, sometimes a wireless capsule camera is used instead of an endoscope, which the patient swallows at the doctor’s surgery. This is called a wireless capsule endoscopy. It is basically a camera inside a pill. This is necessary to view the small intestine, as its size and position makes it hard to view during a traditional endoscopy. The patient wears a data-recording device around their waist so that as the camera capsule journeys through the patient’s digestive tract, the waist device records thousands of images, allowing the physician to diagnose existing conditions.

Conditions that can be diagnosed by endoscopy:

  • gastroesophageal reflux disease
  • ulcers
  • cancer link
  • inflammation or swelling
  • precancerous abnormalities
  • stomach cancer and oesophageal cancer
  • coeliac disease
  • strictures or narrowing of the oesophagus
  • blockages
  • helicobacter (pylori)
  • stomach and duodenal ulcers (peptic ulcers)
  • Barrett’s oesophagus
  • liver disease, cirrhosis, portal hypertension.

 

1 healthdirect.gov.au Colonoscopy | healthdirect

2 Cancer Council: Faecal Occult Blood Tests (FOBTs) | Cancer Council Victoria (cancervic.org.au)

3 ‘Twilight sleep’ is a means of dulling consciousness with sedative and painkilling drugs in order to perform minor procedures. From the Australian Society of Anaesthetists.

This article was originally published in Be Well magazine in March 2022.