Anoscopy
Reviewed
Also called: Anoscopy, High-resolution anoscopy
An anoscopy is a procedure that uses a special lighted scope called an anoscope or anal speculum.
Specimen: Not applicable (procedure). If a biopsy is performed, the specimen is a tissue sample from the anus or lower rectum.
Why this test may be ordered
- To evaluate symptoms such as blood in stool, itching around the anus, swelling, discharge, or painful bowel movements.
- To screen for anal cancer in people with HIV (especially men who have sex with men and adults age 45 or older).
- To investigate possible hemorrhoids, anal fissures, polyps, or inflammation.
Preparation and collection
You may want to empty your bladder and/or have a bowel movement before the test. This may make the procedure more comfortable. Your provider might suggest that you avoid putting anything (like medicines and other products) into your anus for 24 hours before the test. They will let you know if there are any special instructions to follow.
An anoscopy may be done in a provider's office or outpatient clinic. The anoscopy procedure only takes a few minutes. Your provider will then insert a lubricated tube called an anoscope about two inches into your anus. If your provider finds cells that don't look normal, they may use a swab or other tool to collect a tissue sample for testing.
There is very little risk to having an anoscopy or a high-resolution anoscopy. You may have some discomfort during the procedure. In addition, you may have a little bleeding when the anoscope is pulled out, especially if you have hemorrhoids. You may have some soreness or bleeding for a few days after the procedure.
Understanding results
Your results may show a problem with your anus or rectum.
- Problem found in the anus or rectum: An anoscopy can help your provider find problems in the anus and rectum, including hemorrhoids, fissures (tears), and abnormal growths. Limitation: A colposcope may detect small changes in your tissues that the anoscope alone may miss. Next step: Depending on the results, your provider may recommend more tests and/or treatment options.
- Biopsy taken: The biopsy results may confirm or rule out cancer. Limitation: High-resolution anoscopy may be better than regular anoscopy at finding abnormal cells. Next step: If you had a biopsy, your provider may tell you when to expect your results and if there are any special instructions.
- Discomfort or minor bleeding may occur during or after the procedure.
- Standard anoscopy may miss small tissue changes that high-resolution anoscopy could detect, which may lead to false-negative results.
- Findings from anoscopy alone are not diagnostic for cancer; biopsy is required for confirmation.
What to do next
Depending on the results, your provider may recommend more tests and/or treatment options.
- Have you had any symptoms such as blood in stool, itching, pain during bowel movements, or discharge from the anus?
- Do you have any risk factors for anal cancer, such as HIV, or other conditions that weaken the immune system?
- Have you had any previous anorectal procedures or treatments?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.