Inside the world of 3-D printing with a man on a personal mission

“You’ve seen MRIs on a screen – that’s a nightmare – you’re trying to figure out what you are seeing. You’re trying to visualize a kid’s 3-D skull. If a picture is worth a thousand words, this is worth a million. This is the patient’s actual skull shape and the issues that are inside. If it can comfort them and give them more information, it’s a very powerful tool.”

MUSC has two labs that handle 3-D printing, including ZIAN and the Advanced Tissue Biofabrication Center (ATBC), which also produced a replica of Rhett’s skull for the use of his surgeons to prepare for the case. Michael J. Yost, Ph.D., director of general surgery research at MUSC, said the 3-D models help in two main ways.

“First, it provides the surgeon a true-to-life-size 3-D model of the anatomy to use to plan the procedure.  We can print multiples of these models, we can print different sections or cut them apart and reassemble similar to the surgical procedure. It allows the physician to complete several dry runs before actually performing the procedure.”

Yost said the main mission of the ATBC is to develop advanced biofabrication techniques, including 3-D printing and bioprinting. “We are to then translate these technological developments into useful tools to improve patient care, improve outcomes and reduce overall health care costs.”

ZIAN’s 3-D printer uses a photopolymer material that prints with an accuracy of .004 of an inch. CT scans are fed into software that translates them into stereolithography files that can be read by the 3-D printer. They load the machine with the correct material and print. “It tells you to come back in 24 hours and you come back and scrape the skull off with a spatula and you start cleaning it."

The 3-D printer, which functions much as an inkjet printer would, uses a liquid plastic that turns to a solid when it’s exposed to ultraviolet light. As the print head comes across, it lays down either the clear scaffold material or the colored solid material (in this case, white). The UV light comes right behind it, and turns it into a solid.

Semler says the software translates the imaging scans down to the millimeter to match the patient’s physical geometry. “You get a very clear idea of what you’re going to see before you start cutting the skin.”

Semler, who has been involved in 3-D printing for 20 years, said 3-D printing is not new. What has radically changed is pricing and software tools to make the technology much more accessible and affordable. His lab has an Objet 30-pro printer that comes with a $60,000 price tag for an upgraded model. It has superior accuracy and ability to print multiple materials, including clear, multiple solid color and high temperature variations. Rhett’s skull cost about $350 in materials to produce.

3-D printing obviously has a promising future, he said, including new materials that are emerging, such as metals that can be implanted. As 3-D printing becomes more commonplace, it will be easier to get insurance coverage for preoperative planning. The ultimate will be the printing of organs.

Semler, a mechanical engineer, went into medical devices because of family reasons. He lost both parents when he was in high school, his father from cancer and his mother, a heart attack from complications of an asthma attack.

“I suffered losses as a kid, and every skill that I had I wanted to devote to improving patients’ lives. When they come and say they have a kid – a brand new life – absolutely, I want to improve all patients’ lives, but you really wan

t to be able to help kids. This is a no-brainer.”