McKee-Pownall Equine Services | MRI

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MRI

What Is MRI?

MRI is a diagnostic technique using a magnetic field to produce pictures of structures inside the body. MRI signals yield multiple images in the form of “slices” of the foot or distal limb in several different orientations.  MRI provides images of bone, fluid, and soft tissue and can also help to differentiate between active and chronic lesions. This enables us to observe injuries in a way that cannot be seen with any other equipment.

"MRI Information"
 

Examples of MRI Usage

The structure that is imaged most frequently with the MRI is the hoof. The equine hoof is comprised of many soft tissue structures that cannot be seen on x-ray, and cannot be penetrated by ultrasound waves. We are now able to identify damage to these tissues, provide an explanation for many frustrating foot lameness cases, and suggest new treatments and shoeing techniques.

MRI also allows evaluation of bone injury that is not visible on x-rays, such as fluid build-up and bruising, and early fractures before they become obvious cracks. The MRI system is best used when a lameness can be localized to a specific area, such as a particular foot or fetlock, but shows no abnormalities on digital x-ray or ultrasound.

Procedure

The Hallmarq Magnetic Resonance Imaging system allows a scan to be performed on a standing sedated horse, which eliminates the risks of general anesthesia and hospitalization required with traditional lying-down systems. The examination takes about 2 hours to complete. The scans are interpreted and a report is completed within 48 hours.  Major medical insurance often covers a portion of the cost.

MRI Appointments

Appointment times are typically booked within 1 week
12240 Second Line Nassagaweya
519-856-8225
info@mpequine.com
www.mpequine.com

The Benefits of standing MRI

  • High quality diagnostic images of bone and soft tissue
  • Detection of lesions not visible on x-rays and ultrasound
  • Eliminate the risk of general anesthesia
  • Outpatient procedure, no need for hospitalization
  • Major medical insurance often covers a portion of the cost
  • Accurate diagnosis allows earlier, more effective targeted treatment plans and  prognosis

Consider MRI in these situations:

  • Lameness localized to the foot or lower limb by nerve blocks
  • X-rays to not show any injuries/lesions
  • Area not accessible with ultrasound
  • Early detection of bone fractures in race horses
  • Assessing damage after penetrating injuries of the foot
  • After acute onset of lameness during exercise
  • To monitor treatment and healing before returning to work

The Procedure

  • Front or hind shoes are removed to prevent metal interference
  • Horse is sedated, walks into the room, and a leg is placed in the scanner
  • The operator aligns the scanner with the injury site
  • Many images are collected of the injured area, and of the opposite leg for comparative purposes
  • After 1-2 hours the scans are completed, the horse can load up and go home
  • Scans are interpreted and reported within 48 hours
  • No radiation, no known biological hazards

Case Studies

Case 1

This 15 year old QH mare has suffered from intermittent episodes of mild left front lameness but recently her limp has become much worse and is not improving with rest. Nerve blocks confirmed that the pain originated in the foot, but digital radiographs showed only mild navicular changes. An MRI was performed for further assessment.

Diagnosis: This horse has chronic navicular inflammation and has developed a cyst-like (fluid filled) structure within the bone. This weakness has eroded through to the flexor (rearwards facing) surface of the bone and is now causing irritation and adhesion to the deep digital flexor tendon. Unfortunately the prognosis for soundness is very poor with these severe degenerative changes, although Tildren therapy and injection of the navicular bursa did improve her comfort levels significantly. Since the majority of the navicular lesions had not yet affected the bone structure, there was minimal evidence of the damage on radiographs.


Case 2

This 8 year old irish hunter gelding became suddenly 4/5 lame on the right front leg. Nerve blocks indicated that his pain originated somewhere below the fetlock, but digital radiographs did not reveal any lesions. The lameness did not improve with several weeks of rest and poultice (in case of a foot abscess). On re-examination, local anesthesia of the pastern joint caused 100% improvement in his pain. Here are the MRI images.

This horse has a severe bone bruise in the top of P2 (short pastern) that involves the pastern joint surface. Over several months, radiographic signs of arthritis finally began to develop. Since he now had chronic lameness and clinical high ringbone, the pastern joint was fused with plates and screws. Although he cannot field hunt any more, he is happy and comfortable as a pleasure horse.