MRI (Magnetic Resonance Imaging) scans give great detail of the nerves, spinal cord and discs, which are often involved in the process resulting in the patient’s symptoms. They generally take between 20 and 40 minutes to perform, during which time the patients is lying on their back inside the scanner, which, with most scanners, is rather like a long tube. They can communicate with the scanner staff via a microphone and have a "panic button" should they wish to come out urgently. The scans are quite noisy and earphones/plugs will be provided.
MRI scan of the lumbar spine - showing a damaged disc (at L5/S1, the lowest disc on the scan) which is darker than the others and has a tear ( seen as a small white mark) at the back of it.
Newer scanners are now available, where the
patient is much less enclosed. These
are particularly useful for children,
nervous or claustrophobic patients. In some of these units "dynamic
scanning" can now be performed, to see areas of the body, especially the
spine, in different positions. (See "what's
new")
The patient can bend forwards, backwards or sideways, to demonstrate how their pathology changes in these positions. Scans may be performed sitting, lying down, or in practically any position. (For more information visit www.fonar.com/standup.htm)
Occasionally an injection into a vein in the arm is needed to give more detailed information. This only takes a minute or so, but a further scan sequence (or several) are then taken, which may prolong the duration of the scan.