Dr. Jonathan Morris Pioneers Novel Use for Additive Manufacturing, Helps to Save Hundreds of Lives
Pretend for a moment you’re a surgeon, preparing to operate on a patient. Years of training and experience tell you what you should find within, but the human body is an imperfect machine; the exact shape and location of blood vessels, nerves, and bone within each of us is unique, never mind what happens when tumors and birth defects change the rules. A physician’s skill notwithstanding, there’s always some uncertainty over where the next incision should be placed, a clamp tightened, impromptu adjustments and life-altering decisions made with the clock ticking all the while.
Now imagine a surgery where two young lives are at stake. This was the case 11 years ago when Mayo Clinic radiologists Dr. Jane Matsumoto and Dr. Jonathan Morris were asked to assist with the imaging involved in the separation of conjoined twins. Dozens of physicians were involved, each concerned with accurately and efficiently separating the two children. It would become a turning point in his career.
“It was a very complex anatomical problem,” he said. “The surgeon told us that, in cases like these, the only person in the room who can really mentally visualize the life-size three-dimensional data from the CT scan and MRI scans is the radiologist. They needed a way to get the information out of that person’s brain and make it available to the surgical team, so they could better understand the locations of all the arteries, bile ducts, organs, and relationships to the chest wall... So, he asked if we could print a 3D model of the twins’ liver.”
His experience with additive manufacturing goes back to 2001. While working for the National Institutes of Health, Dr. Morris leveraged a 3D printer at the nearby Bethesda Navy Hospital to build a set of pedicle screw trajectory guides, patient-specific jigs that help the surgeon drill screw holes in the correct position. Since then, his efforts to use 3D printing to improve patient outcomes has continued. After the success of the first twin separation, the methodology used to image and print human body parts continued to improve, and under the guidance of Dr. Morris and Dr. Matsumoto, the Mayo Clinic has since opened an in-hospital 3D printing lab at its main campus in Rochester, MN. Today the team prints more than 500 clinical models each year, helping surgeons treat patients with congenital scoliosis, remove primary bone tumors, such as chondrosarcomas, and Pancoast tumors, repair cranial and maxillofacial injuries, and more.
“The 3D-printed models have helped them pioneer different surgeries,” Dr. Morris said. “Instead of simply removing a leg or a kidney to treat a tumor, they’re able to attempt multiple simulated surgeries on a physical model of the patient until they determine the best approach. And once they perform the actual surgery, it goes much more quickly. Blood loss is reduced, the patient is under anesthesia for less time, less invasive approaches can be performed, and the recovery time is shorter. In some cases it can also help reduce overall medical costs.”
Dr. Morris says this isn’t like printing a boat propeller. He and his team have had to become Class II medical device manufacturers within the confines of a hospital, and pushed the boundaries of 3D printing along the way. Special software tools to assist in radiographic image processing (called segmentation) have been created. They’ve developed complete quality assurance programs, and protocols for servicing of the printers in a hospital setting. As decisions were being made about surgical care based on the models, simple concerns such as left vs. right and mirroring of the images became life or death questions. And as the use of the team’s models increased, reliability had to be assured.
“If you're operating on an infant's heart that's the size of a walnut, and you're planning to send a surgical instrument inside a blood vessel three millimeters across, accuracy becomes critical,” said Dr. Morris. “We’ve learned to create test coupons, so we could verify machine calibration. And we’ve worked extensively with the printer companies to assure zero downtime. If I put a 48-hour print job on the machine, there can’t be any worries about whether it will finish in time, or if the build is going to crash. The patient's life is at stake. That’s how important this technology has become.”