After years of teaching cardiovascular anatomy through photographs from books and images from X-rays, ultrasounds and heart specimens, Dr. Ashley Saunders ’98 ’01 thought more could be done: Students who are learning a complex medical subject deserve better than traditional teaching methods.

Over the last six months, the associate professor of cardiology in the College of Veterinary Medicine & Biomedical Sciences worked with Scott Birch, creative director of the college’s Center for Educational Technologies, to develop an innovative way to teach and study cardiac anatomy using 3-D heart models.

Starting with a computer tomography (CT) scan of a live cat or dog heart, the pair uses computer modeling programs to transform CT scans into digital 3-D heart images. Through 3-D printing, the image is brought to life in a detailed plastic resin model that accurately reflects the animal’s heart. While their teaching and future medical applications are endless, the models already prove useful in characterizing heart defects and preparing veterinarians to understand complicated cardiac anatomy procedures.

When Rocko, a wide-eyed six-month-old retriever puppy, arrived at Texas A&M’s Small Animal Hospital with a congenital heart defect known as patent ductus arteriosus—a persistent opening between two major blood vessels from the heart—his owner could only hope for the best.

“When I first heard the murmur of his heart, my heart sank,” said Rocko’s owner, Dr. Brooke Knowlton, a veterinarian practicing in Texas. “He already held a special place in my life, and I knew I had to do everything I could to save him. The cardiologist specialists at Texas A&M were my best chance.”

As part of a project re-characterizing the anatomy of congenital heart disease in dogs with CT angiography, a team of cardiologists created an accurate 3-D model of Rocko’s heart before operating. His heart defect was fixed through a minimally invasive procedure, and Rocko went home a few days later.

Medical Muse 

At age three, Saunders was diagnosed with the same congenital heart defect as Rocko, a condition she now studies in dogs and cats. Her own surgery sparked a lifelong interest in medicine.

The Arlington, Texas, native earned a bachelor’s degree in biomedical sciences and a doctorate in veterinary medicine from Texas A&M. While in veterinary school, she attended a lecture given by a cardiologist who pioneered minimally invasive procedures for congenital heart disease in dogs.

“When I heard dogs could have the same heart defect as I had, I made a conscious decision to become a veterinary cardiologist to save lives as mine once was,” Saunders said.

After completing an internship at the University of Tennessee and a three-year residency in veterinary cardiology at Texas A&M, Saunders joined the Aggie faculty as an assistant professor of cardiology in the Department of Small Animal Clinical Sciences in 2005.

As an educator, she constantly searches for innovative ways to teach students. Her idea to print 3-D canine and feline hearts originated from a desire to change the way students recognize and diagnose heart defects in small animals.

“We live in a 3-D world but typically only have traditional learning materials that display in 2-D,” Saunders said. “I wanted to develop accurate 3-D heart models for dogs and cats that could enhance teaching, research and surgical methods.”

Making the Models

Creating a 3-D model starts with a CT scan of a live animal with a heart condition. The data sets obtained from the scans, which contain detailed information about the defect, are loaded into 3-D modeling software programs. After extensive work to isolate the anatomical structures, which can include tissue, blood and bones, a 3-D model is created that can be viewed, printed and digitally manipulated. These hearts are anatomically accurate to the hundredth of a millimeter, allowing students, faculty and clients to visualize structures.

Birch and Saunders are exploring the models’ teaching applications as well. “With the 3-D plastic models, we can point out arteries, valves and the path of blood flow from a live animal with great detail and also compare normal and abnormal hearts,” Saunders said. “This has never been done before. Instead of cadaver hearts, students can learn from the digital and 3-D models while the animals themselves are alive and at home with their families.”

Using zSpace, an interactive software program that allows users to create and experience a virtual environment, students can study hearts and access an extensive library of 3-D digital models. Saunders is building a learning library of healthy and abnormal heart images and models obtained from CT scans.

Wearing special glasses, students analyze these images using Virtual Holographic 3-D technology that reproduces the heart in midair. And with a precision interactive stylus, students can manipulate the virtual heart by turning it, dissecting it and zooming in or out. This feature gives them an in-depth look at detailed anatomical structures and improves spatial reasoning skills.

“Imagine being able to follow the path of an artery in midair or the path of blood flow through a 3-D image,” Birch said. “Or imagine being able to show a resident veterinarian or a surgeon exactly where to cut before a surgery. The zSpace technology allows this.”

The Cost of Cutting-Edge

Saunders and Birch are setting new standards of teaching for schools across the globe.

Creating and printing high-quality 3-D heart models, however, is expensive. Printers can cost up to $250,000, zSpace workstations are $150,000 each and resources necessary to create these models add up over time.

Saunders envisions a 3-D printer dedicated to teaching in the College of Veterinary Medicine & Biomedical Sciences and a computer lab based on virtual reality with several zSpace workstations and after-hours access for late-night study sessions. The team currently partners with members in the Department of Biomedical Engineering to print prototype complex models.

“These resources would be an investment in the future of learning, research and veterinary medicine,” Saunders said.

With the help of Saunders and this groundbreaking technology, the light that Brooke Knowlton had once seen in Rocko’s eyes is brighter than ever.

“He’s back to being a normal puppy,” Knowlton said. “Something I never thought I would see again.”

To support Dr. Saunders’ research and the College of Veterinary Medicine & Biomedical Sciences, visit give.am/SupportSaunders.


Learn more about zSpace and 3-D printing technology from Dr. Saunders: