Imagerie thermique : efficace pour diagnostiquer des maladies chez nos amis à quatre pattes

Horses, like humans, are susceptible to all sorts of health concerns. While they can't tell people precisely what is bothering them, they can point to problems through changes in body condition, movement, behaviour, and attitude. A list of symptoms usually helps owners and veterinarians focus their attention on a few possible causes. Vets then use diagnostic tools and tests – which range from incredibly simple to exceptionally high tech – to try to determine exactly what’s wrong. If all goes well, the next step is treatment.

As a horse enthusiast, I’ve had the opportunity to see veterinary science in action – and I’ve glimpsed how animal bodies work up close. In many cases, horse owners are present and involved in diagnostic tests and treatments in a way that is neither possible nor desirable in the human medical system. Just this year, I have been at three types of medical imaging procedures, two of which I will never see performed on humans, except maybe as a patient. Veterinarians can use endoscopy (scopes), magnetic resonance imaging (MRIs), computed tomography (CT scans), radiography (x rays), ultrasound, nuclear scintigraphy (bone scan), and thermography (thermal imaging) to help diagnose problems in horses.

Thermal imaging is striking. Writing for The Horse, Joanna L. Robson explains that thermography can "detect metabolic changes related to active inflammation, blood flow, or nerve conduction. Veterinarians typically follow thermography with anatomic imaging to diagnose the underlying disease process at a specific area of activity or concern."

Robson explains how thermal imaging works: "The thermographic camera detects infrared waves on the body surface that are invisible to the human eye and converts them to an image we can see. Consider what happens when you injure yourself: You bang your knee; the area becomes hot, red, and inflamed; and at a cellular level as an immune response, the body releases chemicals such as histamine. Changes in blood flow might directly correlate with inflammation. Thus, at the most basic level, where there is increased circulation there might be inflammation (becoming warmer). The opposite is also true: With chronic disease, scarring, atrophy (muscle wasting/loss), nerve damage, or disuse, areas might become cooler."

The Canada Science and Technology Museum collection contains thermographic equipment from the human medical system. Used by Dr. Ghys at Montreal’s Clinique du Sein Bourassa in the late 1960s and early 1970s, this thermographic system was the first developed specifically for medical purposes. With this camera, the system was used as a diagnostic aid for breast cancer and circulatory obstructions in humans.

Visitors to the museum can learn more about how technologies have shaped the medical world in a brand-new exhibition, Medical Sensations.