What is a high resolution anoscopy?

High resolution anoscopy, or HRA, is an outpatient diagnostic procedure used to examine the anal canal under magnification. It involves the use of an anoscope which is a small plastic tube that is inserted into the anus to inspect the anal canal. A colposcope which is a magnifying instrument is then used to inspect the anal canal and the skin around the anus (perianus). Mild (5%) acetic acid and iodine can be used to help show up tissues. This allows healthcare professionals to obtain detailed images of the anal canal's lining, facilitating the detection of abnormalities, such as precancerous lesions, warts, or other conditions. It is similar to colposcopy, which is used to examine the cervix.

What is the difference between a colonoscopy and a high resolution anoscopy?

Colonoscopy and high resolution anoscopy serve distinct purposes and focus on different parts of the digestive system. A colonoscopy is primarily used to examine the large intestine (colon) and the rectum, whereas HRA focuses specifically on the anal canal and skin around the anus (perianus). 

How often should you have a high resolution anoscopy?

The frequency of high resolution anoscopy may vary depending on individual health factors and specific medical recommendations. Generally, if abnormal cells (anal dysplasia) are identified, then patients may require treatment and on going surveillance. Individuals with particular conditions that weaken the immune system (HIV, immunosuppressive medications) may be at higher risk and therefore may need additional monitoring.

It is essential to discuss your specific situation with your doctor, who will determine the appropriate screening schedule based on your medical history and risk factors.

Is high resolution anoscopy painful?

High resolution anoscopy is a generally well-tolerated procedure, and discomfort is usually minimal. A numbing gel is applied to the anal canal to reduce any potential discomfort during the insertion of the anoscope. Some individuals may experience a mild sensation of pressure, but this should not be painful. Local anaesthetic injection is used if small biopsies need to be taken.

If you have concerns about discomfort or pain, it is advisable to discuss them with your doctor beforehand. They can offer guidance on pain management to make the experience more comfortable.

How can I prepare for a high resolution anoscopy?

Proper preparation is essential to ensure a successful high resolution anoscopy. Your doctor will provide detailed instructions, which may include:

• Fasting: High resolution anoscopy is commonly undertaken under local anaesthetic, and fasting is not required. However, you may be asked to refrain from eating or drinking if you are having your procedure under general anaesthetic.
• Cleansing: There is no need for particular preparation ahead of your procedure. It is important to refrain from enemas, douches, creams or anal intercourse for 24 hours ahead of your anoscopy.
• Medications: It is important to inform your healthcare provider about any medications that you are taking. You may be prescribed painkillers if needed.
• Communication: Be sure to inform your healthcare provider of any allergies, medications (in particular, any blood thinning medication such as warfarin, clopidogrel, apixaban), or medical conditions you have before the procedure.

What are the risks of high resolution anoscopy?

Like any medical procedure, high resolution anoscopy carries certain risks, although they are generally minimal. Some potential risks and complications may include:

• Minor bleeding: After the procedure, you may experience minor bleeding or discharge, which is typically temporary.
• Infection: Although rare, there is a minimal risk of infection at the site of the procedure. Your healthcare provider will take precautions to minimize this risk.
• Discomfort: As mentioned earlier, some discomfort or pressure may be experienced during the procedure, but it is usually minimal.
• Allergic reactions: In rare cases, individuals may experience allergic reactions to medications or materials used during the procedure.

How long does a high resolution anoscopy take?

The duration of a high resolution anoscopy procedure is relatively short, typically ranging from 10 to 30 minutes. However, the exact time may vary depending on factors such as the complexity of the examination and any necessary interventions or treatments. After the procedure, you may be observed for a brief period to ensure there are no immediate complications, and then you can usually return home.