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Anoscopy - what is it, what to expect and how it can help

Read time: 6 mins

Mr Massimo Varcada is a Colorectal Consultant who practices at our hospital.

As well as being an expert in advanced endoscopy, routine and emergency keyhole surgery and endoluminal surgery, he runs an accredited screening programme and offers a diagnostic procedure called a high resolution anoscopy (HRA). This procedure can spot a number of conditions and diseases that can affect the lower part of your intestines and anus.

With November being Men’s Heath Month, we met him to talk about what an anoscopy is and what patients can expect from the procedure.

What is an anoscopy?

An anoscopy is a test that can help identify any abnormalities in your anal canal and the surrounding skin. A high-resolution anoscopy (HRA) uses a microscope, rather than the magnifier in the standard test. This means issues can be spotted and diagnosed much sooner, which is why I choose to offer this service.

An HRA can better identify abnormal cells in the lining of the anus and rectum, so it’s especially helpful to screen high-risk patients, diagnosing suspicious anal lesions, as well as monitoring after anal cancer treatment.

An HRA test can also check for:

  • Abnormal growths, such as anal polyps and warts
  • Tears in the tissue called anal fissures
  • Haemorrhoids (swollen veins around the anus and/or rectum)
  • Inflammation and infectious disease

Why might people need to have an anoscopy?

People might be referred to me for an anoscopy, or I might recommend this to them if I suspect they might have an issue that needs further investigation. I might recommend an anoscopy to people who have symptoms such as:

  • Pain in or near the anus – ulcerations
  • Rectal bleeding
  • Faecal incontinence or constipation
  • Anal itching

An anoscopy is also used to screen high-risk patients, such as those that are immuno-compromised, have routine anal intercourse, have a viral infection, or women with HPV infections.

Are there any risks involved?

No, other than perhaps feeling a bit embarrassed during the procedure! Otherwise, it’s pretty painless. You might feel some pressure or feel like you need to go to the toilet, but this will be temporary. If you have haemorrhoids, you might bleed a little.

What can people expect from the test?

As I mentioned, it’s a common procedure that can be done in 10 – 30 minutes. Whilst it can be uncomfortable, it’s over quickly and people can get on with their day afterwards.

No special preparation is needed, but some medications and supplements can increase the risk of bleeding. This includes:

  • Aspirin
  • Ibuprofen
  • Vitamin E and certain herbs.

For anyone taking these medications, I would advise them on the best way forward ahead of the procedure.

Starting 24 hours before, people should also avoid using any douches, enemas or creams that are applied to the anal canal. It’s is also important to avoid anal sex.

What happens during the exam?

Once a patient has arrived at the hospital and checked in, I will ask them to undress from the waist down or change into a hospital gown.

I’ll ask them to lie down on the examination couch and get into a foetal position.

Anaesthesia or sedation isn’t needed, but I will use numbing gel to make the procedure more comfortable. I’ll then ask the patient to take a few deep breaths to help relax their anal muscles.

For a high resolution anoscopy, firstly I’ll insert the lubricated anoscope (which is a short metal or plastic tube) and then I’ll place gauze or a cotton swab soaked in a mild, vinegar-like solution into the anus. This solution reacts with the lining of the rectum (mucosa) and helps highlight suspicious areas. Sometimes, iodine dyes may be applied to areas of concern to further help reveal abnormal cells. As the anoscope uses high magnification, this means I can see these tissues much more clearly.

Taking a biopsy or brush cytology

After careful and thorough examination, I might need to take a sample if something looks wrong. If this is the case, I would give a local anaesthetic beforehand to minimise any discomfort.

If a sample (biopsy) is taken, some bleeding should be expected for one to two days after, and the area should be fully healed within a week.

After a biopsy, for three days, it’s best to:

  • Avoid heavy exercise. Walking is allowed.
  • Wear loose clothing.
  • Avoid prolonged sitting or standing.
  • Drink plenty of fluids to help prevent constipation.
  • Avoid smoking
  • Not swim or take baths. Showering is fine.

What could the test find?

The procedure can diagnose a number of problems, including:

An abscess

An abscess is a deposit of pus that can cause swelling and other problems in the tissue around it. An abscess may be caused by:

  • A blocked gland
  • A tear in the tissue that has become infected
  • Sexually transmitted infection (STI)
  • Inflammatory bowel disease (IBD) – IBDs include ulcerative colitis and Crohn’s disease.

Anal fissures

Anal fissures are tears in the tissue of the anus that can be caused by:

  • Anal trauma
  • constipation
  • hard, large bowel movements
  • long periods of diarrhoea
  • decreased blood flow

Anal fissures can also appear after childbirth or in people with Crohn’s disease. They can be found in people of all ages and are common in children.


Haemorrhoids are swollen veins around the anus and rectum. They’re common in pregnant women and can also occur due to straining or an infection. These veins can be painful and cause bleeding.


Polyps are growths that protrude from the lining of the anal canal and lower rectum. They’re usually benign, but some can be cancerous. Regular screenings are very helpful in this situation, as they can help prevent polyps from becoming a serious problem.


Cancer can appear in the lower digestive tract, including the anus and the rectum. However, cancers in this area are rare.

What happens after the procedure?

This is an outpatient procedure, which means that once it’s done, patients can go about their day.

The results are normally ready within a matter of days, and then, if required, I will discuss treatment options with the patient – this could include laser, excision or topical treatment.

If you would like to find out more about Mr Varcada or book an appointment, have a look at his profile.

To book an appointment, fill out the form on his page or give our GI Clinic a call on 020 7078 3802 and they’ll find you the earliest possible appointment with him.

Medically reviewed by Mr Massimo Varcada - MBBS MD FRCS FEBS (Coloproctology) on October 2022

Posted on: 16 January 2024