What is an anoscopy?
An anoscopy is a procedure that involves viewing the lining of your anus and rectum with a little tube called an anoscope. To observe these areas, a treatment called high-resolution anoscopy uses a piece of special magnifying equipment called a colposcope in conjunction with an anoscope.
The anus is the point at which the intestines open and the stool exits the body. Above the anus is the rectum, which is a portion of the digestive tract. It’s the last stop for feces before it exits the body via the anus. An anoscopy can help a doctor detect abnormalities like hemorrhoids, fissures (tears), and abnormal growths in the anus and rectum.
What is it used for?
An anoscopy is most often used to diagnose:
- Hemorrhoids, a condition that causes swollen, irritated veins around the anus and lower rectum. They can be inside the anus or on the skin around the anus. Hemorrhoids are usually not serious, but they can cause bleeding and discomfort.
- Anal fissures, small tears in the lining of the anus
- Anal polyps, abnormal growths on the lining of the anus
- Inflammation. The test can help find the cause of unusual redness, swelling, and/or irritation around the anus.
- Cancer. High-resolution anoscopy is often used to look for cancer of the anus or rectum. The procedure can make it easier for your health care provider to find abnormal cells.
Why do I need an anoscopy?
You may need this test if you have symptoms of a problem in your anus or rectum. These include:
- Blood in your stool or on toilet paper after a bowel movement
- Itching around the anus
- Swelling or hard lumps around the anus
- Painful bowel movements
What happens during an anoscopy?
An anoscopy may be done in a provider’s office or outpatient clinic.
During an anoscopy:
- You will put on a gown and remove your underwear.
- You will lie on an exam table. You will either lie on your side or kneel on the table with your rear end raised in the air.
- Your provider will gently insert a gloved, lubricated finger into your anus to check for hemorrhoids, fissures, or other problems. This is known as a digital rectal exam.
- Your provider will then insert a lubricated tube called an anoscope about two inches into your anus.
- Some anoscopes have a light on the end to give your provider a better view of the anus and lower rectum area.
- If your provider finds cells that don’t look normal, he or she may use a swab or other tool to collect a sample of tissue for testing (biopsy). A high-resolution anoscopy may be better than a regular anoscopy at finding abnormal cells.
During a high-resolution anoscopy:
- Your provider will insert a swab coated with a liquid called acetic acid through the anoscope and into the anus.
- The anoscope will be removed, but the swab will remain.
- The acetic acid on the swab will cause abnormal cells to turn white.
- After a few minutes, your provider will remove the swab and reinsert the anoscope, along with a magnifying instrument called a colposcope.
- Using the colposcope, your provider will look for any cells that have turned white.
- If abnormal cells are found, your provider will take a biopsy.
Will I need to do anything to prepare for the test?
You may want to empty your bladder and/or have a bowel movement before the test. This may make the procedure more comfortable. Your health care provider will let you know if there are any special instructions to follow.
Are there any risks to the test?
There is very little risk to having an anoscopy or a high-resolution anoscopy. You may have some discomfort during the procedure. You may also feel a little pinch if your provider took a biopsy.
In addition, you may have a little bleeding when the anoscope is pulled out, especially if you have hemorrhoids.
What do the results mean?
Your results may show a problem with your anus or rectum. These may include:
- Anal fissure
- Anal polyp
- Cancer. The biopsy results can confirm or rule out cancer.
- Depending on the results, your provider may recommend more tests and/or treatment options.