How is the MRI Performed?
All metallic objects are removed such as collars prior to scanning.
Generally the animal is put under a very light general anaesthetic.
Light General Anaesthetic is the preferred method over sedation. The general anaesthetic prevents the animal from moving during the scan and so prevents distortions of the picture obtained.
A MRI scan can be performed with sedation if the animal has a heart condition or at the preferred request of the owner. It should be noted that from a safety perspective there is virtually no difference between deep sedation and light general anaesthesia and the latter maybe actually safer as it can be reversed very quickly.
The animal is then placed on the scanner. Sometimes an additional contrast dye has to be added intravenously to increase the resolution of the picture. This is a rare earth dye generally Gadolinium based and it only effect is to increase resolution in areas of inflammation.
An MRI scan usually on average takes about 30-45 min to complete for a full set of sequences. Longer scans can take up to an hour and a half but this would be the exception. In the case of a short scan where sedation is used rather than the light general anaesthetic; the scan would be on average 15-30mins.
Once the image has been obtained, the animal is removed from the scanner and monitored until it is again awake.
Interpretation of results can then take place and a diagnosis given. The images produced are in the transverse plane but with multi detectors, the resolution of the image can be reconstructed in additional planes giving a 3D representation.