What is Interventional Radiology?
IR, abbreviated for interventional radiology or VIR, short for ( vascular and interventional radiology ) which is a subspecialty of radiology in which minimally invasive prodedures are performed using image guidance. Some of these procedures are done for purely diagnostic purposes ( e.g . angiogram), while others are done for treatment purposes ( e.g. angioplasty). (Images), pictures are used to direct these procedures, which are ususally done with needles or other tiny instruments like small tubes called catheters. The images provide road maps that allow the interventional radiologist to guide these instruments throughout the body to the area of interest.
The training of interventional radiology procedures varies depending on whether you are a physician or a radiology imaging professional such as a Rad Tech or Diagnostic Medical Sonographer. Radiologist Physicians usually complete a prlliminary year of interventional radiology training called an internship followed by a four year diagnostic radiology residency program and then a one or two year fellowship in vascular & interventional radiology. Diagnostic Medical Sonography programs are more commonly offering a focus on interventional procedures as due to high demand for these skilled professionals; however, it is necessary to inquire with specific schools about the specifics within their interventional radiology programs.
Interventional Radiology Training : Common Procedures
- Angiography: imaging the blood vessels to look for abnormalities with the use of various contrast media, including iodinated contrast, gadolinium based agents, and CO2 gas.
- Balloon angioplasty/stent : opening of narrow or blocked blood vessels using a balloon; may include placement of metallic stents as well ( both self expanding and balloon expandable).
- Chemoembolization: delivering cancer treatment directly to a tumor through it's blood supply, then using clot-inducing substances to block the artery, ensuring that the delivered chemotheraphy is not "washed out" by continued blood flow.
- Cholecystostomy : placement of a tube into the gallbladder to remove infected bile in the patients with cholecystitis, an inflammation of the gallbladder, who are to frail or too sick to undergo surgery.
- Drain Insertions : placement of the tubes into different parts of the body to drain fluids (e.g., abcess drains to remove pus, pleural drains ).
- Embolization : blocking abnormal blood (artery) vessels (e.g., for the purpose of stopping bleeding) or organs ( to stop the extra function e.g. embolization of the spleen for hyperplenism) including uterine artery embolization for percutaneous treatment of uterine fibroids. Various embolic agents are used, including alcolhol, glue, mettalic coils, poly-viny alcohol particles, Embospheres, encapsulated chemo-microsphere, and gel foam.
- Thrombosis : treatment aimed at dissolving blood clots (e.g., pulmonary emboli, leg vein thrombi, thrombosed hemodialysis accesses) (TPA) and mechanical means.
- Biopsy : taking of a tissue sample from the area of interest for pathological examination from a percutaneous or transjugular approach.
- Radiofrequency alblation (RF/RFA ) : localized destruction of tissue (e.g., tumors) by heating.
- Cryoablation = localized destruction of tissue by freezing.
- Line insertion : Vascular access and management of specialized kinds of intravenous devices (IVs) ( e.g. PICC lines, Hickman lines, subcutaneous ports including translumbar and transhepatic venous lines ).
- IVC Filters: - metallic filters placed in the inferior vena cavae to prevent propagation of deep venous thrombus, both temporary and permanent.
- Vertebroplasty : percutaneoous injection of biocompatible bone cement inside fractured vertebrae.
- Nephrostomy Placement : Placing a catheter into the kidney to drain urine in situations where normal flow of urine is obstructed. NUS =catheters are nephroureteral stents which are placed through the ureter and into the bladder.
- Radiologically Inserted Gastrostomy or RIG : Placement of a feeding tube percutaneously into the stomach and/ or jejunum.
- Dialysis access and related intervention: Placement of tunneled hemodialysis catheters, peritoneal dialysis catheters, revision/thrombolysis of poorly functioning surgically placed AV fistulas and grafts.
- TIPS : Placement of a Transjugular Intrahepatic Porto-systemic Shunt (TIPS) for management of select patients with critical end stage liver diease and portal hypertension.
- Biliary Intervention- Placement of catheters in the biliary system to bypass biliary obstructions and decompress the biliary system. Also placement indwelling biliary stents.
- Endovenous laser ablation of varicous veins - Placement of thin laser fiber in varicous veins for non-sugical treatment of venous insufficiency.
As you can see, there are many procedures that fall under the category of interventional. These procedures are peformed using different modalities such as CT, Ultrasound, and MRI's, for example. Each one has it's advantages, depending on the type of procedure being performed. The purpose of this article is to get you familiar with common interventional radiology procedures. This is by no means an exhaustive list of procedures that fall under the umbrella of interventional. To learn more about interventional radiology programs, we are currently featuring Sanford Brown Institute, which has a highly acclaimed vascular technology program.