Interventional Radiology Interventional radiology' (abbreviated IR or sometimes VIR for vascular and interventional radiology, also known as Image-Guided Surgery or Surgical Radiology) is a subspecialty of radiology in which minimally invasive procedures 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).