MRI – For Pet Owners

Many of us have either had or know somebody who has had a CT (“CAT” scan) or an MRI at some point in their life. As in human medicine, advances in imaging have significantly increased your vet’s ability to quickly and safely diagnose the cause of a variety of illnesses in companion animals. If your pet needs to have an MRI, your primary care vet will refer you to a local veterinary neurologist or radiologist for evaluation and subsequent imaging if indicated.

In neurology, the clinical signs (“symptoms”) exhibited by a pet depend on where the disease is located rather than what disease process is present. In other words, a brain tumour, stroke, or infection in the same area of the brain cause very similar clinical signs so the cause of your pet’s illness can’t be determined on exam alone. As a result, advanced imaging is required in most cases. MRI allows your vet to quickly and safely provide a more accurate diagnosis of your pet’s illness, in turn, they can then more accurately treat and provide an improved quality-of-life for your four-legged-friends.

MRI provides amazing clarity of the body’s tissues. MRI is the imaging tool most often recommended by veterinary neurologists and radiologists to evaluate the nervous system and sometimes the musculoskeletal system. In contrast to CT, which is better for bone evaluation, MRI is significantly better at imaging soft tissues, such as the brain, spinal cord, intervertebral discs, tendons and ligaments, and muscles.
Very small abnormalities can be detected with MRI that are otherwise missed on CT and other imaging techniques. MRI also allows imaging from all three planes of the body, left-to-right, front-to-back, and top-to-bottom without having to move the patient. This allows your vet to view the body three-dimensionally.

Take a look inside a veterinary MRI.

Unlike CAT scans, which involve taking many X-ray slices through the body, there is no radiation in MRI, so it is incredibly safe. MRI uses a powerful magnet to align the protons in the hydrogen of water molecules of the body in the same direction as the magnetic field. The computer then delivers a brief radiofrequency (RF) pulse that knocks the protons out of alignment. After the RF pulse ends, the protons return to alignment with the magnet, giving off energy that is detected by a receiver (“coil”) placed on or around the patient. This signal is then processed by a computer to provide a detailed image of the body.

MRI for animals is the same as for people, but unfortunately, our pets will not lie still! Any movement blurs the images which doesn’t allow for evaluation of the pictures. As a result, dogs and cats must be placed under general anaesthesia for the MRI. While this can be scary to consider, anaesthesia risks are usually very low; most pets do very well under anaesthesia and your pet will be closely monitored throughout.

Once safely under anaesthesia, the procedure usually takes between 45 minutes and 2 hours to complete, depending on the region of the body being scanned. During this time, your pet will be closely monitored by a vet technician. Since your pet is under anaesthesia for the procedure, and for patient safety, only the region of interest is scanned. Once the images are obtained, they are evaluated by a neurologist or radiologist and discussed with your own vet who will make a treatment plan, designed specifically for your pet’s speedy recovery.

To find out how much an MRI scan for your pet will cost, we advise that you speak with your own vet or nearest MRI provider.

Every pet is different, and so is every pet insurance policy. To find out whether your own policy covers the cost of an MRI scan, we strongly advise you to speak with your insurance company first.