An image guided needle biopsy is a minimally invasive procedure in which a needle is passed through the skin, using image guidance, into an abnormal organ in order to obtain a small amount of tissue for diagnostic purposes. Image guidance permits precise placement of the needle into the abnormal tissue with minimal risk of damage to adjacent organs.
A biopsy may be necessary to learn the nature of a newly diagnosed mass lesion. The most common causes of mass lesions include tumors and infection. Also, biopsy is often performed to determine the type and severity of kidney and liver disease.
Image-guided needle biopsy, when performed by an interventional radiologist with appropriate training and experience, is a safe technique. Like all invasive procedures, complications and side effects may occur. These will be explained to you in detail before you give your consent. The pierce of the needle through the skin may cause some discomfort but this will be minimized as much as possible by the use of local anesthetics (numbing medication) and sedation medication. If necessary, general anesthesia is available.
You will be given written instructions at the time of scheduling the procedure. Preparation for needle biopsy includes not eating solid food for eight hours prior to the procedure and not drinking clear fluids for three hours prior to the procedure. Additional blood tests and imaging examinations (computed tomography, magnetic resonance imaging, ultrasound) may be needed prior to the biopsy procedure.
Needle biopsy is most often performed with ultrasound guidance, but CT or fluoroscopy guidance may also be used. The interventional radiologist examines the area to be biopsied with imaging guidance. The ability to see the structures inside the body during needle passage permits the interventional radiologist to accurately place the needle and avoid adjacent organs. The skin is cleaned with a special iodine solution and sterile drapes are placed over the area to avoid infection. Local anesthetic (numbing medication) is injected into the skin. Once the area is numb, the interventional radiologist passes a special type of needle through the skin into the area of abnormality. When the needle is removed, it contains a small piece of tissue. This tissue sample is examined by a pathologist before the procedure is completed in order to make sure that an adequate specimen has been obtained.
The pathologist will determine what type of cells or infectious organisms it contains. In the case of certain tumors, additional specimens can be obtained in the same manner and studied for their genetic content.
Biopsy results are usually available within 24 hours. A Pathologist performs interpretation of the cytology and permanent tissue sections. Special tissue stains and immuno-histochemical techniques may be required to render a more meaningful diagnosis. These techniques may delay the final interpretation of your biopsy. Your primary doctor or Interventional Radiologist will help you obtain the results in a timely fashion and explain their relevance.