Image guided aspiration and biopsy

What is image guided aspiration and biopsy?

Image guided aspiration and biopsy is a procedure where a doctor uses a needle to take a small sample of tissue or fluid from inside your body, so it can be tested in a laboratory. An imaging method, such as ultrasound, CT, or X-ray, is used to guide the needle precisely to the area that needs to be sampled.

Why might I need one?

Your doctor may refer you for this procedure if they've found an abnormal area on a scan, or a lump, and need to know more about it. The sample is examined under a microscope to diagnose or rule out cancer or infection, and to get more specific information about the cells involved.

It can be used to sample tissue from many parts of the body, such as:

• the liver or kidney
• a lymph node
• the peritoneum (the lining of the abdomen)
• a lump in the breast, thyroid, or a salivary gland (the glands that produce saliva).

It's also sometimes used to check whether cancer has spread to nearby lymph nodes, or whether it's come back after previous treatment.

What are the benefits of having it?

Using imaging to guide the needle helps your doctor take a good-quality sample from precisely the right area, giving a more reliable answer to their question about the abnormality. It also helps to avoid nearby structures, which reduces, though doesn't remove, the risk of complications.

The procedure is usually done under local anaesthetic, so you don't usually need a general anaesthetic or to stay in hospital overnight.

Are there different types of the test?

There are two main ways a sample can be taken:

• Aspiration: This uses a fine needle to draw off fluid or a small number of cells
• Biopsy (sometimes called a core biopsy): This uses a slightly wider needle to remove a small piece of solid tissue.

The imaging method used to guide the needle also varies. Ultrasound is the most commonly used, but CT or X-ray guidance may be used instead, depending on where the sample needs to be taken from.

How do I prepare for the test?

You'll usually have an assessment beforehand, either in person or over the phone, along with blood tests to check your kidney function and blood clotting.

Before your procedure, tell your care team if you:

• take blood-thinning medication (anticoagulants), such as warfarin, aspirin, clopidogrel, rivaroxaban or apixaban, as you may need to stop or adjust these temporarily
• have recently been diagnosed with, or are being treated for, a blood clot
• are taking, or have recently stopped, antibiotics
• think you may have an infection
• have any allergies, including to latex or plasters
• have a severe fear of needles.

You may be asked not to eat for 6 hours beforehand, and you'll be asked to change into a hospital gown. It's a good idea to bring someone with you, as you won't be able to drive yourself home afterwards.

What happens during the test?

The procedure itself usually takes around 20 to 60 minutes.

1. You'll have an initial scan, usually ultrasound or CT, to plan exactly where the sample needs to be taken from
2. If you feel anxious, you may be offered a mild sedative to help you relax; you'll need to lie still throughout the procedure
3. Your skin is cleaned with an antiseptic solution, and a sterile cover is placed over the area
4. Local anaesthetic is injected to numb the skin – this may sting briefly before it goes numb
5. A small cut may be made in the skin, and the needle is guided into the exact area using the ultrasound, CT, or X-ray images
6. If you're having a CT-guided biopsy, the table moves in and out of the scanner several times, and you may be asked to hold your breath for a few seconds at a time
7. The needle takes the sample – you may hear a clicking sound, and more than one sample is often needed
8. A dressing is applied to the site once the sample has been taken.

What happens after the test?

Afterwards, you'll be looked after on a ward while staff regularly check your pulse and blood pressure. You may need to stay for around 2 to 4 hours, though this varies depending on which part of the body was biopsied.

Some people need to stay in hospital overnight, particularly if they've travelled a long way for the appointment or live alone. You'll need someone to take you home and, ideally, stay with you overnight, as you shouldn't drive yourself.

Keep your dressing clean and dry for 3 days. You're advised to rest for 1 to 2 days and avoid strenuous activity for 5 days afterwards.

You can take your usual painkillers, such as paracetamol, if you're uncomfortable, though you may be advised to avoid anti-inflammatory medication for a few days. Some discomfort at the site is normal and should settle on its own.

Your referring doctor may get an initial report within a few days, and a full laboratory report anywhere from about 5 days to 2 weeks later, depending on the tests needed.

Contact your GP or local minor injuries unit if you notice:

• excessive bleeding from the site
• increasing pain, swelling, redness or warmth
• swelling in your neck, armpit or groin
• a fever or chills.

What are the risks or side effects?

Image guided aspiration and biopsy is a common procedure with an overall low risk, but as with any medical procedure, there can be complications. The specific risks depend on which part of the body is being sampled, and your doctor will discuss these with you.

• Bleeding, which usually causes minor bruising; more serious bleeding is uncommon but can sometimes need a procedure, or rarely surgery, to control it
• Infection, which is uncommon
• Problems with the organ being sampled, such as a fluid leak or reduced function
• A small risk of harm to nearby organs or structures near the needle's path, though imaging guidance reduces this substantially
• Serious complications needing major surgery, or in rare cases death, though these are quite rare.