After the recent controversies regarding both Marmelo and Ispolini and the ‘new’ technology used to determine their fitness to race in the Melbourne Cup, I thought it was time for some educational information regarding the ‘new’ technology now being employed to determine race fitness. Below is general information to provide race enthusiasts interested to know what is CT, what’s new about the University of Melbourne’s CT and a prediction for the future when it comes to new technology and horse welfare.
What is CT?
Computed Tomography (CT) was invented in the early 1970’s — not so ‘new’ technology after all. CT is basically a three dimensional x-ray. X-rays have the ability to pass through just about any object or material. X-rays and CT are commonly used to diagnose bone related disease processes in both humans and animals. Another area where you will see x-rays used on a daily basis is in the security line up at the airport when scanning carry-on luggage.
When an x-ray is fired at a horse’s leg, the x-rays pass through the skin, tendons and bone, and are detected by a special plate on the other side of the leg. Different tissues in the body have different densities. Bone is more dense than skin and tendons, therefore less x-rays pass through to the plate. This difference in density allows us to determine what structures are present and visualise pathology, like fractures.
A typical x-ray system produces a 2-dimensional image. This means, to see different pathology, we need to take more than one x-ray. This becomes problematic when looking for stress fractures as they are very small and sometimes difficult to locate using an x-ray. A CT system fires a constant beam of x-rays, spinning 360 degrees around the region of interest. The CT system has a complex computer that reads the images in 2 dimension and creates a 3-dimensional picture.
Both x-ray and CT have been used to diagnose fractures in horses of years. There are many scientific papers describing the diagnosis of fractures both using x-ray and CT.
What is ‘new’ about the University of Melbourne’s CT scanner?
In the veterinary field, CT scanners produced for human imaging are re-purposed for use in animals. Because animals can’t be told to ‘sit still’ while the CT scan is being performed, animals are either heavily sedated or placed under a general anaesthetic (ie knocked out). In the case of a horse, it requires a general anaesthetic to be transported onto a special table that helps to feed the horse in and out of the CT scanner.
There are risks associated with general anaesthesia in the horse:
- Cardiac arrest (heart attack)
- Myopathy (muscle damage) / Neuropathy (nerve damage)
Given the short duration required for a CT to be performed, myopathy/neuropathy are unlikely, however still possible. The issue occurs if we suspect a fracture in the horse and we need to perform a general anaesthesia to accurately diagnose the fracture for further surgical planning. That horse is at high risk of fracturing the affected leg when it recovers from anaesthesia. The reason is that when horses recover from anaesthesia they are very wobbly when they first stand up. This can place excess load on the fractured limb and cause it to de-stabilise. We can reduce these risks by rope recovering horses or applying a cast to the fractured leg for recovery.
Recent advances in the electronics industry has allowed companies to produce more streamlined devices that have large computational power – like our smartphones. This technology has filtered into the medical imaging field. Instead of a CT machine being in a fixed position and moving people/animals through it, CT machines now can move around the person/animal. The University of Melbourne recently installed the first standing CT for the use in horses in Australia.
In a nut shell, the ‘new’ part of the story is just the way the CT is performed and now we don’t need to perform a general anaesthetic to accurately diagnose a fracture in the lower leg of the horse. The standing CT uses the same technology as the re-purposed CT machines used in veterinary hospitals throughout the world. The ability to perform standing CT means there are minimal risks compared to a traditional CT that requires general anaesthesia.
We can now easily and quickly perform CT as a screening procedure for horses at high risk of lower limb fracture. Horses that travel from overseas appear to be at higher risk of fracture than our local Australian horses. There are likely multiple factors associated with this increased risk such as:
- long periods of rest due to quarantine and international travel
- different track surfaces on arrival
- interruption in training/preparation
Ultimately we are trying to eliminate as much as possible, injury to the horse. If we can become better at predicting injury, we reduce the chances of race day accidents from occurring.
Changes for the future of racing
Unless you have been living under a rock — technology, data collection and data analytics has taken over every industry on the planet – horse racing is not immune to this change. This will bring about a wave of new technology and analytics, and this is not just for the punter — this is for the welfare of the horse. This technology aims to predict injury and improve transparency in an industry that is infected with secrecy.
Wearable devices are ubiquitous in our lives and they will form part of data collection and analysis used to determine a horse’s ability to compete. strideMASTER has been involved in Tasmania Racing since 2011 to collect speed, sectional time, stride length and stride duration. This data is not just collected on race day but also throughout the horses preparation. Over time, predictive algorithms can be developed to determine the horse’s fitness to race.
Another wearable device that has gained popularity is the Lameness Locator by Equinosis. This system uses gyroscopic and accelerometer sensors to objectively measure the horse’s gait. By collecting this type of information, we can start to decide if a horse has a ‘unique’ action or is truely in pain and is lame.
We’ve spoken about standing CT, however other advanced imaging modalities include high field MRI (requires general anaesthetic), low field MRI (standing system available), nuclear scintigraphy (bone scan) and PET (Positron Emission Tomography). Both nuclear scintigraphy and PET are part of the diagnostic labelled radiopharmaceutical industry. This type of imaging can help show ‘hot spots’ indicating a fracture. Recently, a standing PET scanner was developed and will be available at Santa Anita Park in California. PET scanners are high resolution and can be used to detect micro-fractures in bone.
The ABC report was not the start of the changing views of public opinion of the racing industry. Race attendance has been on the decline for the past 5 years and sponsorship is becoming harder and harder for race clubs to secure. If the racing industry opens up to the new technology that is and will be available in the future it will be the start of a new and improved chapter in the history of racing — rather than the end.