Test Overview
Magnetic resonance imaging (MRI) is a test done with a large
machine that uses a magnetic field and pulses of radio wave energy to make
pictures of the knee. Muscles,
ligaments,
cartilage, and other joint structures are often best
seen with an MRI. In many cases MRI gives information about structures in the
body that cannot be seen as well with an
X-ray,
ultrasound, or
CT scan.
For an MRI test, you are placed inside the magnet so that your knee
is inside the strong magnetic field. MRI can find changes in the structure of
organs or other tissues. It also can find tissue damage or disease, such as
infection or a tumor. Pictures from an MRI scan are digital images that can be
saved and stored on a computer for further study. The images also can be
reviewed remotely, such as in a clinic or an operating room. Photographs or
films of selected pictures can also be made. See
MRI images
of the knee
.
In some cases, a
contrast material may be used during the MRI scan to
show certain structures more clearly in the pictures. The contrast material may
be used to check blood flow, find some types of tumors, and show areas of
inflammation or infection. The contrast material may be put in a vein (IV) in your arm.
Should I have an MRI or arthroscopy to
diagnose a possible torn meniscus?
See pictures of
a standard
MRI machine
and
an open
MRI machine
.