What to expect when you horse has an MRI
How the Hallmarq MRI Standing Equine Scanner Works
The Hallmarq MRI standing equine scanner has revolutionised the way lameness is diagnosed. It does not require your horse to be anaesthetised as with some ‘high field’ MRI scanners.
The procedure is non-invasive, and unlike X-rays uses no ionising radiation. It has been successful in giving a rapid diagnosis in 90% of cases, and causes minimum stress to the horse.
Watch the video to see a horse having a lameness exam and MRI
1. Initial examination.
On arrival for the scan the horse’s overall health is evaluated for sedation and a final check of the lameness, although the referring vet’s advice on the exact place of lameness will normally be relied on. The MRI scan can be used on fore or hind legs from the hoof to the carpus.
The standing MRI machine eliminates the need for anaesthesia, so removes the mortality risk and ensures day patient scheduling. Sedation is applied when the horse enters the scanner, and top up doses may be applied during the scan.
3. Horse shoes
Metal horse shoes would degrade the quality of the images if left on as the MRI scanner contains a large magnet, so the shoes on both the leg to be scanned and the adjacent leg are removed
The scanner produces a strong magnetic field; short pulses of radio waves are applied to the limb, the effect is a weak radio echo from which the MRI image is created by computer analysis.
The horse is walked into the MRI scanner, with the lame leg placed between the poles of the magnet. It is crucial the operator aligns the scanner with the site of the injury to achieve accurate results. With a pilot scan taking place to ensure the scan is in the right place.
6. The Scan
The whole process including scanning takes around one to two hours, producing around 300-500 images showing multiple angles of the limb or hoof and highlighting different types of tissue and pathology.
After the scan the horse is given time to recover from the sedation, and in most cases the horse will return home the same day.
The vet responsible for scanning will carefully review the images to arrive at opinion about likely pathology or injury. This is communicated to the referring vet, who will then be able to take other case information into account when reporting back to the owner on the findings.
The findings from the scan will enable an accurate diagnoses to be made, with precise information available the vet can prescribe the best possible treatment for the horse