We live in a three-dimensional world — a world of height, width, and depth. Our lives do not exist on a two-dimensional plane. Even a child knows holding a three-dimensional object leads to a better understanding of that object — an understanding that cannot be matched by looking at pictures in a book. It is why children of all ages build models of airplanes, cars, and trains.
The love of model making that begins in childhood often grows into a necessity for more complex models in numerous professions. Architects, industrial designers, and aerospace engineers have all been using models for countless decades in order to better understand their craft.
Physicians have, naturally, done the same thing — utilizing models of human anatomy in order to learn, teach, and better understand the body. A generic, factory-made three-dimensional model of a non-existent person or perfect organ can aid a physician only so much when they are confronted with a very unique problem in a very unique, very real individual.
From printer to operating room
“Here at the Children’s Hospital of Illinois, we have the capability of taking CT (Computerized Tomography) or MRI (Magnetic Resonance Imaging) data, but that data does not translate into three dimensions without effort,” explains Dr. Matthew Bramlet, pediatric cardiologist at the Children’s Hospital of Illinois and Director of Jump Simulation Advanced Imaging and Modeling (AIM) — a part of OSF HealthCare Innovation Center and a collaboration with the University of Illinois College of Medicine at Peoria.
That effort comes into play after the CT and MRI scanners capture their multiple two-dimensional image slices of the patient’s body. These slices are then stacked like layers in a sandwich until an image of the heart can be separated from the resultant overall image. From that 3D information, Dr. Bramlet can either print out a model of that specific patient’s heart in three dimensions — thanks to the innovation center’s 3D printer — or upload it to a virtual reality environment.
“For congenital heart disease,” he says, “we have transformed our standard of care to include not just the CT or MRI high-quality imaging but also the ability for the clinician to hold that patient’s very specific heart in their hand prior to medical decision making.”
Dr. Mark Plunkett, congenital cardiac surgeon with Children’s Hospital and OSF Saint Francis Medical Center, explains just how invaluable that model can be: “We know exactly what the intracardiac anatomy looks like and what the three-dimensional relationship of the structures are, so we can accurately plan the repair well before going to the operating room. What that allows us to do is not only expedite the repair but also perform a more accurate repair with a lot of confidence. We know exactly what the anatomy will be.”
Time is of the essence
A true appreciation of the value of this 3D technology can only be had after gaining a fundamental knowledge of congenital heart defects and just how varied they can be.
During the first 10 weeks of fetal development, any interruption or alteration in that development can lead to a heart defect or malformation, which can negatively affect the infant.
“We tend to categorize these heart defects with 30 or 40 different labels,” Dr. Plunkett explains, “but within each of those categories there’s an entire spectrum of different defects; like the analogy of the snowflake, no two are exactly alike.”
Although the standard imaging techniques are adequate for surgeons to strategize their surgical repairs on simpler defects, very complex cases, particularly those with a complex intracardiac anatomy, can be extremely challenging. Doctors find it especially difficult to define those defects prior to surgery when relying simply on the imaging modalities of MRI, CT, and echo.
In other words, the more accurate the planning stage, the lesser the likelihood of there being any surprises in the operating room. “In the past, we have sometimes found while in the operating room the anatomy was not exactly what we anticipated,” Dr. Plunkett says.
“Therefore, we either had to alter our surgical plan or change it entirely to facilitate what we were going to do because the anatomy had not been defined clearly up front.”
While in the operating room, time is most certainly of the essence. The patient is on a heart/lung machine and often the heart has been stopped and is open. “So anything that can be done to expedite the process, shorten the length of time on the heart/lung machine, and shorten the length of time the heart is arrested, will lead to better outcomes,” adds the doctor.
Recognized potential
Improvements in medical care on this scale are obviously not something the OSF doctors want to keep to themselves. The potential for 3D printing in biomedical applications is almost limitless; physicians are just scratching the surface.
“[For example,] after spending 15 years working on an influenza virus, a researcher spent 15 minutes with the physical 3D printed model of the virus,” Dr. Bramlet shares. “They instantly saw where they could lay down an antibody against that virus.”
For years, physicians have been trying to understand complex 3D objects through 2D surrogates, the doctor continues. “But when we translate it back into an actual 3D object — either virtually or physically — we have an improved understanding of that object, which allows for improved communication.”
Communicating these models is why the National Institutes of Health (NIH) is supporting a library of 3D digital files for biomedical use. “They recognize the need to share that information openly. As congenital heart disease has so many different varieties, there is a tremendous value of having a library of these defects,” Dr. Bramlet says. “We had the anatomist from Penn State up in our lab a little while ago. They thanked us for contributing to that library because they were downloading them in their anatomy classes and showing their students the different varieties of congenital heart disease.”
“That’s exactly why we wanted to contribute,” continues Dr. Bramlet. “So, instead of having to find a pathological library of defects or even going through textbooks, which are 2D representations of pathology, you can actually understand it, get your hands on it and understand the complex defects well.”
Always moving forward
As with any new technological leap, no matter how impactful, the biggest hurdle to jump is cost. Drs. Bramlet and Plunkett consider themselves very fortunate for a private endowment to help them move forward as well as almost limitless engineering resources from the University of Illinois College of Engineering. “Our goal is to take that generosity and not just make it happen here but show how we can create a model anybody can put in place anywhere,” Dr. Bramlet says.
“From a surgical standpoint,” Dr. Plunkett chimes in, “the next step on this is to print these 3D models in a more malleable material that you can cut and sew. Up until now, these hearts have been generated in a plaster material, which is wonderful for examining the anatomic details, but you can’t do anything else with it. If you actually had a model of the child’s heart made with a softer material, you could not only do the operation the night before on that heart — kind of a batting practice — you could train future residents, fellows, and pediatric heart surgeons to perform these operations prior to entering the operating room. That would be invaluable.”
Again, doctors are just starting to scratch the surface. Dr. Bramlet foresees not only a better understanding of congenital heart defects through 3D modeling and imaging but also an expanded effort toward other areas of medicine, specifically oncology. “We just did our first liver tumor case in the past week or two,” he shares.
“Everything we touch turns to gold when it comes to 3D modeling,” the doctor continues. “Whenever we take complex 3D problems and display them in an intuitive 3D output, there’s tremendous value for the one who’s actually going to be making a decision on it. It’s a wide open playing field. It’s just a matter of finding those magical moments where it will have a tremendous impact on the outcomes.”
One cannot argue with those outcomes, particularly when they include reducing the cost of care, bringing it to more people and, of course, saving more lives.
If you are interested in learning more about the Advanced Imaging and Modeling program at Jump Simulation, a part of OSF Innovation, please visit jumpsimulation.org.