Easier eye exams on dogs
A simulated eyeball makes it easier for Vet Med students to learn how to examine canine patients.
Dogs, like children, won’t always sit still when you want them to.
This is particularly true when shining the bright light of a transilluminator into a dog’s eye to evaluate its retina.
“You have to get the dog’s head to stop moving around, get the right angle and you have to keep adjusting the light and lens,” says Jesse Tong, a University of Calgary Faculty of Veterinary Medicine (UCVM) student. “Try doing this for the first time when the dog squirms and won’t stay still, it’s definitely hard.”
Now, a 3D printed replica of the head and eyeball of a dog named Lily, owned by one of UCVM’s faculty, is making learning the eye examination procedure a little less squirmy.
Drs. Chantal McMillan and Heidi Banse collaborated with Dr. Brian Skorobohach, a local veterinary ophthalmologist, and Doug Kondro, a biomedical engineering graduate student supervised by UCVM's Dr. Mark Ungrin, to create a simulator for teaching funduscopic (back of the eye) examinations — a difficult technique.
Lower-fidelity models that use hollow spheres with shapes on the back representing the retina have been studied in veterinary medicine. But the faculty wanted to make the eye itself more realistic and to include important anatomical features such as the skull and eyelids that can impact the procedural aspects of the skill.
“With a funduscopic examination you’ll have a lens and a transilluminator and you’ll shine it into an eye and you can see the retina on the back of the eye. You’re able to judge the health of the eye based on this,” says Kondro. “So you can put a picture of a retina on the back of our simulator eyeball, then you can look at the retina. Or for teaching purposes you could put little letters or words so the student needs to focus in properly and see those words.”
First collaboration was designing 3D rooster feet
Kondro’s first collaboration with UCVM was designing 3D printed prosthetic feet for a rooster named Foghorn who’d lost his feet to frostbite. Because he was working on a surgical simulator project with Dr. Matt Read, Kondro had a CT scan of Read’s border collie’s head — and that gave him an idea.
“I was trying to think of a holder for these eyeballs and then I thought of using the actual information for a dog for it. What you can do with CT scans is tell the computer what parts you want to keep, and I said I wanted to keep the face of the dog,” explains Kondro. “So I had a 3D model of the face of the dog and then I 3D printed a mold for that face. I then inverted part of the face, poured silicon into the mold and rotated it around so I'd get a rubber dog face.”
As well as being useful for students to practise and gain experience doing eye exams, the model can also be used when testing the skills of students.
“We can put different types of markers back there and test students to see what they’re actually seeing, if they’re focusing correctly,” says Skorobohach, who teaches veterinary ophthalmology. “In a live animal, you can’t put a lesion in the back of their eye, whereas in a model you can put words or images back there and test students on what they see.”
'Whenever I have time I make dog eyeballs'
This is the first year students have been using the eyeball simulator and Dr. Chantal McMillan is happy with the results.
“Students will have the opportunity to become more adept at the procedures before their clinical year,” says McMillan. “Our goal is to develop gold standard teaching protocols for this technique in the live animal and model in addition to validating the model.”
A small grant made it possible for a team of collaborators — Drs. Matt Read, Kent Hecker, Heidi Banse, Brian Skorobohach and Chantal McMillan — to research this model in a clinical setting and to pay Kondro, who is working on a master’s in biomedical engineering, to help develop the model along with his supervisor.
“This technically isn’t what my master’s is on,” Kondro says. “It’s a side project so whenever I have time I make dog eyeballs.”
The University of Calgary’s multidisciplinary Engineering Solutions for Health: Biomedical Engineering research strategy is focused on developing solutions for pressing health challenges in disease and injury prevention, diagnosis and treatments. We are also applying systems engineering principles to continuously improve the health system.