Interventional radiology (IR) is a medical subspecialty that performs various minimally-invasive procedures using medical imaging guidance, such as x-ray fluoroscopy, computed tomography, magnetic resonance imaging, or ultrasound. IR performs both diagnostic and therapeutic procedures through very small incisions or body orifices. Diagnostic IR procedures are those intended to help make a diagnosis or guide further medical treatment and include image-guided biopsy of a tumor or injection of an imaging contrast agent into a hollow structure, such as a blood vessel or a duct. By contrast, therapeutic IR procedures provide direct treatment—they include catheter-based medicine delivery, medical device placement (e.g., stents), and angioplasty of narrowed structures.

The main benefits of interventional radiology techniques are that they can reach the deep structures of the body through a body orifice or tiny incision using small needles and wires. That decreases risks, pain, and recovery compared to open procedures. Real-time visualization also allows precision guidance to the abnormality, making the procedure or diagnosis more accurate. These benefits are weighed against the additional risks of lack of immediate access to internal structures (should bleeding or a perforation occur), and the risks of radiation exposure such as cataracts and cancer.