Pet Columns, Office of Public Engagement, College of Veterinary Medicine at the University of Illinois at Urbana-Champaign

University of Illinois at Urbana-Champaign

U of I logoCollege of Veterinary Medicine

Back to search page.

MRI Expands Diagnostic Options for Equine Patients

Pet Column for the week of April 2, 2007

Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
Sarah Dowling
Information Specialist

"When presented with a lame horse, veterinarians use a variety of diagnostic tools to attempt to pinpoint the problem," says Dr. Kristen O'Dell-Anderson, a veterinary specialist in diagnostic imaging at the University of Illinois Veterinary Teaching Hospital in Urbana.

But when routine approaches--such as a general lameness examination, radiographs, nerve blocks, nuclear medicine, and ultrasounds--fail to find the source of the lameness, specialists at the Illinois referral center have a new option: magnetic resonance imaging (MRI).

While the teaching hospital had previously offered MRIs for its small animal patients, in March it acquired a new MRI machine with an open-magnet design capable of imaging the neck, brain, and lower extremities of horses and other large animal patients.

Problems of the foot and fetlock are the most common reason to use MRI for equine patients. The hoof surrounding the bones in a horse's foot makes it extremely difficult to diagnose soft tissue lameness with conventional methods. An MRI can distinguish between soft tissues and bone in a way that other diagnostic methods do not allow, so that veterinarians can assess the health of all tissues within the foot and get a clearer picture of the disease or injury.

"If other approaches fail, we can use MRI to examine the soft tissue and bony structures more closely," says Dr. O'Dell-Anderson. "We have been very happy with the image quality and diagnostic ability of the machine."

Radiographs of the feet are taken prior to the MRI exam to ensure that no metal that may negatively affect the exam, such as from horseshoes, is present. Like all MRI magnets, this 0.3 tesla unit will also wipe out credit cards and interfere with pacemakers that come within a range of about 12 feet.

The equine-capable MRI machine is also used to image a variety of ailments in small animal patients. Dr. O'Dell-Anderson explains that an MRI is helpful when diagnosing neurological problems in cats and dogs, as well as distinguishing between an infection, trauma, or a tumor in the brain. Dogs are also frequently referred to diagnostic imaging to discover the cause of sudden-onset paralysis or other problems of the spine. In the future MRI may be used to evaluate musculoskeletal disorders, such as injuries in the stifle (knee), in small animals.

The MRI room contains its own anesthesia and monitoring equipment for both equine and small animal patients. Patients must be anesthetized because of the length of time an MRI takes. Unlike human patients, animals can't be asked to hold still for an extended period.

"One benefit of the MRI service at our hospital is our ability to offer 'one-stop shopping' for our patients," says Dr. O'Dell-Anderson. "Animals under general anesthesia for the MRI can be moved immediately to the O.R. if the findings from the MRI suggest that surgery is needed."

A related technological advance at the Veterinary Teaching Hospital is the updated Picture Archiving and Communications System, which has virtually eliminated the need to print images from radiographs (X rays), ultrasounds, MRIs, etc. Instead the images are accessed from a networked database or copied to a CD. The Illinois college was one of the first veterinary schools in the nation with this capability in the late 1990s. The updated version of this system is much more versatile and user-friendly.

"Our goal is to be able to email the diagnostic images taken at our hospital to the veterinarian that referred the patient," says Dr. O'Dell-Anderson. This service would improve the transitional care for patients when they return to their veterinarian and improve the partnership between the hospital and referring veterinarians.