Closing in on Anatomic Replication
Written on January 5, 2017 by Matthew Bramlet
The purpose of medical imaging from the very beginning was to figure out ways to look inside the body and learn what’s going on structurally and physiologically. To that end, physicians used x-rays or performed exploratory surgeries for decades to identify disease or injury. Then came the ultrasound in the 1960s that gave clinicians real-time images of internal body structures using sound waves. Imaging techniques progressed even further in the 1970s with the advent of CT scans and MRI, which are both commonly used today.
It’s my belief that 3D modeling will be the next critical tool used by physicians to not only diagnose, but improve surgical planning, patient outcomes and the education of future clinicians. It has the power to essentially produce exact replications of soft tissue structures, improving understanding among doctors and patients alike. But first, it will take collaboration across the U.S. to make this a reality.
I recently spoke at the American Heart Association-Midwest Affiliate’s Heart Innovation Forum to advocate for imaging techniques that lead to anatomic replication. The Advanced Imaging and Modeling (AIM) team at Jump Simulation has come up with a semi-automated process to convert CT and MRI scans into 3D digital images that can be printed or integrated into virtual environments like augmented and virtual realities (AR and VR). What we’ve learned is that these nearly perfect 3D surrogates of anatomy can’t happen without working to create quality images from the start.
Garbage In, Garbage Out
The old adage “garbage in, garbage out” applies directly to 3D modeling. The standard across the nation for the last ten years has been to quickly produce images that might not have the best quality but lead to diagnosis in an efficient and productive manner. The ability to print or view these images in three-dimensions, though, requires a little more time and effort but leads to discoveries we’ve never seen before.
There is a quality standard that must be met each step along the continuum of 3D modeling translation. If the image is poor – fail. If the segmentation is poor – fail. If the print is poor – fail. If the VR translation is poor – fail. The focus of our cardiovascular imaging efforts at OSF HealthCare is to generate the highest quality images we can attain.
Most recently, we sent a quality focused 3D heart digital file to the incredible engineers at Caterpillar’s additive manufacturing lab. They have a printer that allows us to produce a heart in a soft enough material that can be cut with a scalpel, allowing surgeons to effectively practice on a patient’s heart before surgery. The result was incredible. Not only were we able to practice the surgery before the operation, but we were able to see anatomic detail like never before seen, prompting an entirely new set of possibilities where 3D printing could potentially improve patient care.
Making a Case for High-Quality Imaging Standards
There are many physicians around the U.S who understand the impact 3D modeling can have on surgical planning, patient outcomes and the education of future clinicians. In fact, a group of us are working with the National Institutes of Health and the American Heart Association to create accuracy and quality standards for the Jump Simulation-curated 3D Heart Library, an open-source digital repository of hearts with congenital defects on the NIH 3D Print Exchange. However, I recognize there are still some skeptics out there who don’t understand the value of this technology.
My experience with these models has been that they give surgeons a point of reference they haven’t had before, giving them the ability to make informed decisions before operating on patients. They make viewing anatomical images intuitive across all medical specialties. 3D models give patients and their families a better understanding of procedures they may have to undergo. They also allow educators to easily explain different types of congenital heart disease and what they look like to physicians looking to master the skill of diagnosis or surgery.
Physicians are busy and it’s difficult to put the time and effort into higher quality imaging. However, doing so leads to exact anatomic replications and, in my opinion, is the next big jump in medical imaging surrogacy. It’s going to take clinicians making medical decisions or planning surgery to be impacted by this for the advocacy to come through the clinical community.
Dr. Matthew Bramlet is the lead investigator for Advanced Imaging and Modeling at Jump. He specializes in children with congenital heart disease. In his role as the Director of Congenital Cardiac MRI at Children’s Hospital of Illinois, Dr. Bramlet combined the program’s resources with those at Jump to pioneer anatomically accurate 3D congenital heart models.
This expertise has led to Dr. Bramlet becoming a curator with the NIH 3D Print Exchange’s Heart Library, a nationwide collaborative effort to improve the education and understanding of congenital cardiac anatomy. He is also an Assistant Professor of Pediatrics in the Pediatric Cardiology department at the University of Illinois College of Medicine at Peoria.