Like endoscopy and colonoscopy, a sigmoidoscopy is a procedure involving a camera. It is inserted into your back passage, although the camera is only inserted a small way into your large intestine. As such, the camera may be rigid, although today most sigmoidoscopes are flexible, similar to those used in a colonoscopy.
This test does not require any preparation and is usually done in the consulting room. The doctor passes a thin rigid tube with a light attached into the back passage. The tube only goes about 10cm inside but this may be enough to see an area of inflammation or the cause of some types of bleeding. The test takes 2 minutes to do. Although it may be undignified to have someone look up your bottom, it does not hurt, unless you have an anal fissure.
At the same time as doing the sigmoidoscopy, the doctor can also do a proctoscopy. This test also uses an even smaller rigid tube with a light on the end. This test looks for haemorrhoids (piles) and anal fissures only. It is possible to do treatment for haemorrhoids during a proctoscopy test but we do not offer this treatment at present.
This test is done in hospital in the endoscopy suite. Unlike colonoscopy, you do not need to prepare your bowel the day before your appointment.
When you arrive at the hospital, the nurse will give you an enema. An enema involves having a liquid inserted into your rectum. This gives you a feeling of needing to open your bowels. A few minutes later you will go to the toilet and clear the lower intestine of its contents. This makes it possible for the doctor to see inside clearly.
The procedure itself is minimally invasive and is unlikely to cause much discomfort or pain.
Most people do not need to be sedated for this test. If you are worried, however, the doctor can easily give you a sedative medicine, which will make you sleepy. If you choose to have a sedative, you will need to make sure that someone takes you home as you should not go home by yourself. You should also not drive a car for the rest of the day after you have had a sedative.
Once the camera has been inserted into the rectum, the doctor will observe your bowel and may take photographs or biopsy samples, depending on what is seen.
Possible findings include irritation and inflammation. These may be seen in infection, ulcerative colitis or Crohn’s disease. Sometimes the doctor will see polyps and can remove these. Rarely there may be signs of cancer. The doctor will use these observations to decide on a diagnosis and a treatment plan for you.
Sometimes, after the sigmoidoscpy, the doctor may want to send you for further testing. The sorts of tests vary but are covered in the other pages. Please keep reading to find out more.