Magnetic resonance imaging (MRI) angiography is a non-invasive imaging test that uses a strong magnetic field, radio waves and a computer to create 2-D or 3-D images of blood vessels in the left knee. The scan helps provide good soft-tissue images to distinguish between healthy tissue from diseased tissue. Your doctor may advise this test to check for unexplained knee pain, find problems with knee joints such as arthritis, bone tumours, or infection, or damaged cartilage, meniscus, ligaments, or tendons, and determine if knee arthroscopy is needed.