Arthrogram VS. MRI: What are the Key Differences?

mri scan

What is an MRI?

Often times patients will experience pain or changes in the body that cannot be defined from a physical exam. The pain could be a chronic issue that has increased over the years or from an acute injury that needs immediate attention. A physician may order an MRI to further evaluate the issue and get a close look inside. It assess problems beyond the scope of an X-ray. Magnetic Resonance Imaging (MRI) creates detailed images of the human body through magnetic field and radio waves and without the use of radiation. Detailed image slices are formed that can clearly see joints, cartilage, ligaments, muscles, and tendons. In addition to injuries, it can also diagnose diseases in the brain and other soft tissues, such as a stroke or multiple sclerosis. ENTs will even order MRIs to rule out reasons for hearing loss or vertigo. MRIs can be ordered with a contrast medium that is injected into a vein to see additional details. After the MRI, the images are sent to a radiologist that is specifically trained in evaluating and reading them. He or she will write a detailed report of the findings that the ordering physician can use to
treat the patient.

What is an MRI Arthrogram?

Occasionally, an MRI does not provide a full picture of certain structures in the body. Joints, specifically shoulders, hips, knee, and occasionally wrists and ankles are unique because tears in tendons, cartilage, and ligaments are so small and covered by tissue that MRIs will often miss the injury site. Commonly overlooked in a standard MRI, SLAP tears can cause considerable pain, but patients struggle for a proper diagnosis without the imaging of an Arthrogram. This specialized test will garner additional diagnosis in many types of tears and injuries throughout the body’s joints. An arthrogram is a focused image of the joint using a contrast medium, or dye, infused directly into the injured joint (instead of a general vein). The on-sight radiologist uses fluoroscopy (a continuous X-ray “movie”) to direct the contrast needle into the proper position before and during injection. Once complete, images are taken using an MRI to monitor how the contrast moves and highlight any potential injury. The arthrogram diagnoses specific joint injuries more clearly and effectively than an MRI alone.

Key Differences:

  • MRI provides a detailed look at most body structures including soft tissues
  • An Arthrogram uses fluoroscopy and an MRI to specifically diagnoses injuries in the joint structures that an MRI alone would likely miss
  • MRIs can be ordered with contrast that is delivered intravenously, while an Arthrogram has contrast needle-guided directly into the injured joint