CT is similar to x-ray. It uses ionising radiation to capture multiple images from different angles, combining them all to create a 3D image. The horse is walked onto the flat, open, standing CT platform, and positioned with the limb to be imaged central to the plate and x-ray machine. The CT machine rotates 360 degrees around the leg so that images are taken from every angle. A 3D image of the limb is created using motion correction technology to adjust for any minor movements of the limb. The whole process takes just a few minutes.

Yes. Advanced imaging techniques, including CT, require specialist equipment which is not usually portable. CT uses ionising radiation, so it is important that imaging is performed at a clinic where appropriate radiation safety measures are in place

Not necessarily. Shoes are usually only removed if the foot is being imaged (similar to x-ray). Whilst it is not dangerous for the shoes to remain on whilst CT is performed, it is best to remove shoes when imaging feet so that anatomy can be clearly seen in the image.

The scanning process takes a minute, during which time movement of the limb may result in a blurry scan. Although, Hallmarq’s award-winning motion correction technology adjusts for slight movement, it is important the horse remains still throughout the procedure. Mild sedation helps keep the patient calm during imaging and encourages even weight bearing on all limbs which helps ensure optimum image quality.

A CT scan takes just 60 seconds to produce 900 images which are reconstructed to create a 3D picture of the limb. Occasionally the scan may need to be repeated, for instance if the horse has made a sudden movement. The whole process from start to finish only takes around 15 minutes.

Images are usually reviewed by the vet responsible for the scan. Depending on the case, images may also be reviewed by a radiologist. Findings on the likely condition or injury are then sent to your own vet to discuss with you if you have been referred for CT.

Standing CT is used where lameness has been localised to either the fetlock, pastern or foot and a bony injury is suspected. It is very useful in providing a clear picture of subtle bony damage such as a small joint chip or change in the density of bone and injuries such as a fracture or a foot penetration where surgery will be performed. A 3D image will give a clear understanding of where the fracture line or penetrating tract extends. Contrast within a joint or tendon sheath can highlight injuries to some soft tissue structures but if a soft tissue injury is suspected, MRI is normally recommended either instead of, or in combination with, standing CT.

The usefulness of each imaging modality depends on the question you are trying to answer. Standing CT produces detailed 3D imaging of bony structures in the distal limbs, providing valuable information to assist with surgical planning and complete evaluation of small bony injuries. CT will be most useful when a bony lesion is suspected and may be used in combination with other complimentary imaging.

Yes, all veterinary imaging is very similar to human imaging. Equine standing leg CT uses cone beam CT, the same type of technology commonly used in mammography and dental imaging in people. This has the advantage of visualising fine bone detail whilst exposing the patient to a relatively low dose of radiation.

In short, no. This is a non-invasive diagnostic technique. Imaging can be performed under light sedation and only takes a matter of minutes. The process is very similar to x-ray and involves use of ionising radiation. Therefore, safety precautions for the vets and technicians, including use of lead screening, are used.

With an accurate diagnosis, you can make the best decision for your horse, moving forward with a treatment plan that is more likely to result in a good outcome. Whilst advanced imaging costs are likely to be higher than first line imaging, the use of empirical treatments may result in a short-term improvement in the horse’s condition, whilst the underlying injury continues to deteriorate.

Most UK insurance companies cover the costs of advanced imaging. Some will ask that you cover a certain percentage of the costs and other policies might exclude certain conditions or treatments. Always check with your own insurance company first.