Arthrography is medical imaging to evaluate conditions of joints. In addition to its diagnostic role, we uses fluoroscopic guidance to inject steroids and anesthetic into joint space, resulting in significant pain relief and an increase in joint function for selected patients.
Conventional arthrography is the x-ray examination of a joint that uses a special form of x-ray called fluoroscopy and an injection of contrast material containing iodine directly into the joint. Alternate methods of arthrography examinations use magnetic resonance imaging (MRI) or computed tomography (CT).
An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
Fluoroscopy makes it possible to see bones, joints and internal organs in motion. When iodine contrast is injected into the joint, it fills the entire joint and becomes clearly visible during x-ray evaluation, allowing the radiologist to assess the anatomy and function of the joint. Although the injection is typically monitored by fluoroscopy, the examination also involves taking radiographs for documentation. The images are most often stored and viewed electronically.
Similarly, MR arthrography also involves the injection of a contrast material into the joint. The contrast material used for MR evaluation is different from that used for x-ray; it contains gadolinium, which affects the local magnetic field within the joint. As in conventional arthrography, the contrast material outlines the structures within the joint and allows them to be evaluated by the radiologist after the MR images are produced.
MRI uses a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then be examined on a computer monitor, printed or copied to CD. MRI does not use ionizing radiation (x-rays).
CT arthrography uses the same type of contrast material as conventional arthrography and may be supplemented by air to produce a double contrast CT arthrogram. CT makes cross sectional images processed by a computer using x-rays. Once the joint space is localized with one of these methods, anesthetic or steroids can be administered.