Interventional Radiology (Image-Guided Therapy)

July 25, 2024

This page was reviewed under our medical and editorial policy by Jonathan Kessler, M.D., associate clinical professor, Division of Interventional Radiology, Department of Diagnostic Radiology, City of Hope^® Cancer Center Duarte

Interventional radiology (IR) is a form of advanced image-guided therapy that involves a variety of procedures that may be recommended during cancer diagnosis and treatment.

What Is Interventional Radiology?

IR uses advanced imaging technologies to get closer to cancer cells and tumors inside the body, without the need for major surgery.

IR procedures are considered minimally invasive because many methods require only tiny pinhole incisions and local anesthesia. This means that patients may be spared from troublesome side effects and complications. In recent decades, IR has been performed in place of surgery to help improve treatment precision and success.

When interventional radiology is used to treat cancer, it is sometimes called interventional oncology. It targets and treats many types of cancer in order to help downstage the disease, which means reducing its spread and tumor size. This may also make it possible for doctors to move forward with other lifesaving treatments, such as a transplant.

In addition, interventional oncology often plays a key role in biopsy (tissue sample collection). Biopsies help doctors find cancer, understand more about it and appropriately plan cancer treatments.

Cancer infusion treatments like chemotherapy are also sometimes delivered through chest ports and catheters placed using IR. Doctors may also utilize IR treatments to reduce patients’ cancer pain symptoms, provide comfort and improve their quality of life.

What Is an Interventional Radiologist?

Interventional radiologists are board-certified doctors. They are experts in the use of advanced image-guided radiology like ultrasound, computed tomography (CT) scans, X-rays and magnetic resonance imaging (MRI) to diagnose disease and perform minimally invasive procedures such as biopsies.

Interventional radiologists are trained and tested to ensure they have a comprehensive understanding of patient care, imaging studies and interventional radiology procedures in order to deliver today’s modern medicine. They also work with the patient’s primary care doctor, any specialists who refer patients to their care and a multidisciplinary hospital care team.

This collaborative approach to treatment solutions helps to improve successful outcomes for patients, even when traditional treatments are not working or are not an option.

Types of Interventional Radiology Procedures

IR procedures include the following diagnostic studies, implants, treatments, biopsies and symptom relief measures.

Angiography

Angiography is used to view blood vessels (arteries) near cancer to help plan surgery and limit blood loss. A small slit is made over a blood vessel and a catheter (tube) is inserted into it and moved to the target site. Dye is then injected into the catheter and pictures of blood vessels in the area are taken using X-rays (high-energy radiation) or a CT scan (X-rays combined with computers to produce 3D pictures). Sometimes, an MRI (utilizing radio waves, a magnet and a computer) is used to take images instead, which does not always require dye.

Angioplasty

Cancer patients have an increased risk for developing coronary artery disease (CAD), and this procedure is used to treat a fatty deposit (plaque) blockage that is associated with CAD. Using guided X-ray imaging, a catheter that has an attached balloon is inserted into a blood vessel in the groin. When the catheter reaches the blockage, the balloon is inflated in order to stretch and unblock the blood vessel.

Ascites Treatment

Ascites is fluid buildup in the abdomen. It may happen with certain cancers, as well as other conditions such as liver disease. Cancer cells are sometimes found in the abdominal (belly) fluid in advanced-stage cancers. Interventional radiology treatments use different image-guided techniques to remove the fluid.

Paracentesis: This is a treatment option used to remove ascites fluid. An interventional radiologist inserts a thin needle into the abdomen to draw out the fluid, typically using ultrasound guidance (images generated using sound waves) to help improve the success rate of the procedure.

TIPS procedure: TIPS stands for transjugular intrahepatic portosystemic shunt, and it is also used to treat ascites. It may also be used to treat hydrothorax (fluid buildup in the chest) and internal bleeding for people with liver damage. Using X-ray guidance, a small mesh tube called a stent is placed into a hepatic (liver) vein to connect it to another liver vein called the portal vein in order to reduce pressure and fluid buildup.

Thoracentesis: For this procedure, an interventional radiologist inserts a needle between the ribs into the pleural cavity (tissue area lining the lungs and chest) to draw out fluid, typically using ultrasound or CT scan guidance. This is used to treat a buildup of fluid in this area (called pleural effusion), which may contain cancer cells.

Biopsies

Bone marrow biopsy: This is a tissue sample taken of the bone marrow using CT imaging scan guidance. A core needle (wide needle) is typically inserted into the hip and rotated to withdraw the tissue, and the sample is then studied under the microscope to check for cancer cells or other abnormalities. It is used to help diagnose certain blood or bone marrow disorders, including anemia and cancers such as lymphoma, leukemia and multiple myeloma.

Endoscopic biliary biopsy: This procedure is used to diagnose issues in the bile duct, such as pancreatic or bile duct cancer, benign (noncancerous) tumors and infections. A long, thin instrument with a camera (endoscope) is inserted down the esophagus, into the stomach and through the first part of the small intestine (duodenum). Air is pumped through the endoscope to make the area easier to see. Then, the interventional radiologist locates the bile ducts that empty into the small intestine. Using fluoroscopy imaging (a type of X-ray that takes motion pictures), a catheter is inserted through the endoscope, through which dye is placed to make the bile ducts clearer. Small tools are then inserted through the endoscope to take a tissue sample for biopsy.

Image-guided biopsy: Interventional radiologists may perform image-guided biopsies in areas throughout the body. During this procedure, a thin, hollow needle is inserted into the body site using guidance from CT or ultrasound imaging. The tissue sample is removed through the needle and sent to the laboratory to be inspected for cancer cells.

Kidney biopsy: A thin, hollow needle is inserted into the kidney using guidance from CT or ultrasound imaging. The tissue sample is removed through the needle and sent to the laboratory to be inspected for kidney cancer cells. 

Liver biopsy: A hollow needle is inserted into the liver tumor through the abdomen using guidance from CT or ultrasound imaging. The tissue sample is removed through the needle and sent to the laboratory to be examined for the presence of liver cancer cells.

Lung biopsy: A fine needle aspiration procedure is performed to look for cancer in the lymph nodes surrounding the lungs or for smaller masses in the lungs. It uses a thin, hollow needle that is inserted using different techniques to draw out the tissue sample, which will be checked for cancer in the laboratory. Sometimes a larger (core) needle is used to obtain bigger samples. Ultrasound, CT scan or fluoroscopy are the imaging methods of choice to capture pictures and guide lung biopsy procedures.

Transjugular liver biopsy: To help prevent issues like bleeding for those who have blood-clotting issues, sometimes a liver biopsy is performed by inserting a needle into the jugular vein of the neck and down into the liver to obtain the tissue sample. The interventional radiologist uses CT or ultrasound imaging to help guide the needle.

Embolization

Tiny particles, such as little sponges or beads, are placed into blood vessels to clot the blood and stop its flow to certain structures, such as to cancer tumors. It is used to treat conditions such as liver and kidney cancer, neuroendocrine tumors and fibroids in the uterus. Different types of embolization use various guided-imaging techniques.

Chemoembolization: In this type of embolization, a substance that helps to block the flow of blood and a chemotherapy drug are injected into an artery that feeds a tumor. The treatment is delivered through a catheter inserted into a blood vessel in the groin through a small incision. It is typically used to treat liver cancer. Sometimes it is also used to treat cancers that started elsewhere in the body and then spread (metastasized) to the liver.

Radioembolization: This type of embolization combines radiation therapy that destroys tumor cells with another substance that blocks a tumor’s blood supply. Guided by live X-rays, a catheter is inserted into an artery in the leg or wrist until it reaches the tumor, and then a radioactive embolization agent is inserted into the catheter. This procedure may be used to treat liver cancer or cancer that has spread to the liver.

Prostate artery embolization: In this type of embolization, a small incision is made in a patient’s wrist or groin and a tiny catheter is inserted until it reaches the prostate artery. An embolization agent that is designed to deprive the prostate gland of blood, resulting in decreased prostate size and improvement in prostate-related urinary symptoms. The procedure is performed to treat an enlarged prostate gland.

Feeding Tubes

The delivery of nutrition right to the gastrointestinal tract, or gut, is accomplished through feeding tubes that are inserted into various natural or created openings in the body. There are several feeding tube options (listed below) and, depending on the type, an interventional radiologist may use guided-imaging technology to insert them. They are used for many reasons, including anorexia from chemotherapy or radiation therapy treatments, narrowing of the esophagus (stricture), trouble swallowing (dysphagia) and abdominal surgery.

A nasogastric feeding tube is inserted through the nose into the stomach, and its proper placement may be verified using an X-ray. It is used to provide temporary nutrition to people who have issues with swallowing, vomiting, emptying their stomach, intestinal blockages and gastroesophageal reflux (gastric reflux), and sometimes to provide extra nutrition during the healing process.

A nasoduodenal tube is similar to a nasogastric tube, except it is inserted into the first part of the small intestine, called the duodenum, rather than into the stomach. It may be used if a patient is not able to absorb nutrition through the stomach, such as if they are experiencing nausea and vomiting. 

A nasojejunal tube is like nasogastric and nasoduodenal tubes, but it's inserted through the nose. Its tip is placed in the middle of the small intestine, called the jejunum.

A gastrostomy tube is a feeding tube placed directly into the stomach through a small incision on the belly. Using X-ray and ultrasound guidance, the interventional radiologist will identify and access the stomach with a small needle. Then, through this small access, the physician will guide the feeding tube into the stomach through the skin. It is typically used for patients who require direct nutrition over the longer term.

A jejunostomy procedure is similar to a gastrostomy tube placement, only this feeding tube is inserted into the middle of the small intestine (jejunum) rather than into the stomach.

Inferior Vena Cava Filter (IVCF)

If patients are at risk of having blood clots break free from their leg veins and travel to their lungs, an IVCF may be inserted. It is used if blood-thinning medication has failed, or the patient is not able to take blood thinners. X-rays are used to guide the placement of a filtering device into the large vein (vena cava) in the abdomen that drains into the legs. This temporary device filters out or “traps” any blood clots while letting the remaining blood flow through.

Interventional Pain Management

Kyphoplasty and vertebroplasty: These procedures use X-ray imaging to insert surgical cement into collapsed vertebrae (compression fractures) in the spine to help ease patients’ pain. The vertebrae may collapse due to injury or certain cancers, such as multiple myeloma. In vertebroplasty, a hollow needle is used to insert the cement through the back and into the vertebrae. In kyphoplasty, a balloon is placed into the inserted needle and inflated before the cement is injected. This balloon helps restore vertebrae height and reduce the risk of cement leakage.

Nerve ablation: Also called neuroablation, this is a procedure that uses focally damages nerves so they no longer send pain signals. It may be used for pain caused by many different health issues, including cancer pain that is resistant to pain medications or other treatments.

Lymphangiography

This is a procedure that uses MRI or X-ray imaging to check a patient’s lymphatic system, including the lymph nodes, lymph vessels, bone marrow and other structures. It helps doctors plan surgery and discover leaks and blockages.

Ports and Catheter Placements

A variety of different vascular access devices can be placed into patients’ veins to allow for intravenous infusions of a variety of agents and medications, including chemotherapy drugs, intravenous (IV) fluids, nutritional mixes, immunotherapy, targeted therapy and medications like anti-nausea treatments. Interventional radiologists use imaging tools to guide their placement.

Central venous catheter (CVC): This is a type of flexible catheter that is typically inserted near or in the superior vena cava, a large vein that goes into the heart. It may stay in for several months or more. It is often used for patients whose other veins are not able to receive IV infusions due to damage, weakness or small size. 

PICC lines: A peripherally inserted central catheter (PICC) is a type of central venous catheter inserted through an arm vein and moved into a vein that goes to the superior vena cava, the large vein that goes into the heart. The end sticks out of the arm and needs to be covered so it does not get wet. A PICC is flushed out after each infusion and may be left in for days or even months. 

Implanted port (port-a-cath): These central venous catheters may include chemotherapy ports or ports used for other infusions. As their name implies, they are implanted under the skin using a minor surgical procedure. They are typically placed in the upper chest region and, unlike PICC lines, do not get wet (although they will still need to be flushed out after each infusion). A port needle is placed under the skin and into the port by a nurse or other medical practitioner, and tubing is attached to this needle to give the infusions.

Stenting

A stent is a woven mesh device that is placed in a blood vessel or other area in the body where cancer or other problems are resulting in blockage of flow. This can be used to relieve blockages of arteries, veins, intestines, bile ducts, airways and a variety of other conditions. The stents are placed under image guidance to allow for precise targeting and placement.

Thrombolysis and Thrombectomy

Thrombolysis and thrombectomy procedures help clear blood clots. Thrombolysis delivers medication directly to a blood clot through catheters placed into the clot using image guidance. The medication helps break up the blood clot faster than other methods, typically within a day or two. Thrombectomy uses a mechanical device inserted directly into the blood vessel to physically remove the blood clot. It may be used in conjunction with thrombolysis or alone.

Tumor Ablation

Microwave ablation: Ablation means to remove or destroy. Microwave ablation is a procedure in which a tumor is located using image guidance. A microwave antenna that gives off electromagnetic waves is then placed into the tumor using a probe, and these waves create friction and heat to destroy tumor cells. Microwave ablation is used to treat a variety of types of cancer, such as liver cancer, lung cancer, kidney cancer and bone cancer.

Cryoablation (cryosurgery): Here, tumors are ablated (destroyed) using a cryoprobe that freezes the cells. The cryoprobe is placed within the tumor using CT, ultrasound, or MRI guidance. Cryosurgery is used for both cancer and potentially cancerous conditions, including liver cancer, lung cancer, kidney cancer and bone cancer.

Benefits of Interventional Radiology Procedures

Interventional radiology has a multitude of potential benefits over conventional surgical procedures, including:

• Fewer treatment complications and side effects, including less damage to healthy tissues
• Shorter recovery times
• Highly accurate solutions targeted to each patient’s unique needs and goals
• Typically higher levels of safety, compared to surgical alternatives
• Improved quality of life for the patient
• Innovative options for patients not responding to traditional treatments
• A collaborative, multiteam approach to therapy to help improve patient outcomes

Interventional Radiology at City of Hope

The benefits of advanced interventional image-guided procedures include the ability to treat a wide array of cancers and conditions of the blood, as well as a multitude of disease symptoms like pain, nutritional deficiencies and fluid buildup.

City of Hope’s groundbreaking interventional radiology research and care play an important role in the development of innovative image-guided therapies and programs. Patients experience care that is collaborative and focused on specialty areas, allowing them and their loved ones to focus on reaching their treatment goals.