Needle biopsy is a medical test performed by an interventional radiologist to identify the cause of a lump or mass, or other abnormal condition in the body.
Drainage involves using a catheter (a thin tube) to drain an abscess or a collection of fluid or air under image guidance.
When Is This Procedure Conducted?
An image-guided biopsy aims to provide diagnostic information by obtaining a sample of tissue from under the skin using imaging to navigate. The tissue sampled will usually be examined under a microscope by a pathologist and can also be analysed chemically.
Drainage is recommended to treat fluid or air collections, which produce symptoms (such as pneumothorax, which is the collection of air or gas in the gap between the chest wall and the lungs). It is also used to treat recurrent fluid collections by using medication and is a minimally invasive method of draining abscesses.
This procedure may not be suitable for you if you suffer from a blood clotting disorder or if the interventional radiologist cannot find a safe access route for the catheter.
How Does This Procedure Work?
If you are on any medication that prevents blood clotting, you will stop taking it before the procedure, if possible.
You should not eat anything for at least four hours before the procedure starts. You may be asked to fast for longer, depending on the puncture and the complexity of your particular case. Before the procedure, the interventional radiologist will usually place a needle in your vein to make access easier during the procedure.
The interventional radiologist may use one of a number of image-guidance techniques to plan and monitor the placement of the needle during the aspiration procedure, including ultrasound, CT, MRI and fluoroscopy. This depends on the location and nature of the lesion or fluid/air collection or abscess.
Most biopsy and drainage procedures are performed under local anaesthesia or conscious sedation, so you will be awake but feel no pain. You may be asked to take antibiotics beforehand to reduce the risk of infection, but this is uncommon. You will lie down for the procedure – the exact position you will be asked to lie in depends on the access route that the interventional radiologist will use to safely approach the lesion.
The procedure will be carried out in a sterile and safe environment. The interventional radiologist will choose which type of needle to use according to the organ and tissue type which needs to be sampled, such as bone, soft tissue, lung, etc. The interventional radiologist will insert the needle and will guide it using imaging until the needle tip can be seen inside the lesion.
An image-guided biopsy and drainage can be performed as an in-patient or out-patient procedure. The site of the puncture and your vital signs will be monitored for 4-6 hours following the procedure. You will experience some mild discomfort around the puncture site during this time. If you undergo a lung biopsy, you will be given a chest X-ray 6-8 hours after the procedure to ensure that no air has been trapped in the cavity between your chest wall and your lungs. If you have had an abscess or fluid drained, the interventional radiologist will periodically follow up using imaging to confirm that the abscess or fluid collection has gone.
In most cases, you will be allowed to drink water a few hours after the biopsy procedure.
How Will I Feel After The Procedure?
You may feel some mild pain in the area of the injection site, which can be treated with pain medication.
You will need to take it easy for the rest of the day and will be able to resume normal activities the next day.
How Successful Is Needle Biopsies and Drainage?
Image guided biopsies are a safe and highly effective way of providing further diagnostic and accurate information to physicians in determining the nature and cause of lump masses and treatment protocols.
Drainage is a successful ongoing treatment for abscesses and fluid/air retention, without the need for surgery.
Summary of Benefits of Needle Biopsies and Drainage
- Biopsies provide diagnostic and accurate information to physicians in determining the nature of a lump mass
- Biopsies are a safe and effective procedure
- Drainage allows abscesses to be drained without the need for surgery
- Drainage is an effective treatment in reoccurring fluid collection