Sigmoidoscopy is a procedure used to see inside the sigmoid colon and rectum.
Why Sigmoidoscopy is Performed
Your doctor may recommend this test to look for the cause of:
- Abdominal pain
- Diarrhea, constipation, or other changes in bowel habits
- Blood, mucus, or pus in the stool
- Weight loss
This test can also be used to:
- Confirm findings of another test or x-rays
- Screen for colorectal cancer or polyps
- Take a biopsy of a growth
How Sigmoidoscopy is Performed
You will be asked to lie on your left side with your knees drawn up to your chest.
Your gastroenterologist will perform the test.
The doctor will carefully place a gloved and lubricated finger into your rectum to check for blockage and gently enlarge (dilate) the anus. This is called a digital rectal exam.
Next, a flexible tube with a camera on the (sigmoidoscope) is placed through the anus. The scope is gently moved into your colon. Air is inserted into the colon to enlarge the area and help the doctor see better. The air may cause the urge to have a bowel movement or pass gas. Suction may be used to remove fluid or stool.
The doctor may take tissue samples with a tiny biopsy tool inserted through the scope. Heat (electrocautery) may be used to remove polyps. Images of the inside of your colon may be taken.
Sigmoidoscopy using a rigid scope may be done to treat problems of the anus or rectum.
How Sigmoidoscopy Will Feel
During the exam you may feel:
- Pressure during the digital rectal exam or when the scope is placed in your rectum
- The need to have a bowel movement
- Some bloating or cramping caused by the air or by stretching of the bowel by the sigmoidoscope
After the test, your body will pass the air that was put into your colon.
Children may be sedated for this procedure.