From Sci-Fi to Fact

Emerging medical applications of intricate 3-D printing techniques are changing 鈥 and saving 鈥斕齦ives
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When the doctor pulled the plastic skull out of the box, Southfield mother Shaura Pearsall instantly recognized it as the head of her infant son, Jonah.

鈥淚t looked exactly the same except for the smile on his face,鈥 says Pearsall. Jonah鈥檚 Crouzon syndrome prematurely fused his skull and facial bones, inhibiting their growth, distorting his head鈥檚 shape, and threatening his brain development.

As Beaumont Hospital鈥檚 Dr. Kongkrit Chaiyasate showed Pearsall the custom model, made with a 3-D printer, special software, and Jonah鈥檚 CT scan to explain in detail the surgery he proposed, she could see how thin her child鈥檚 skull was, and therefore easy to cut and reshape. It also helped Pearsall ask questions and better fight the battle of being a parent to a special needs child.

鈥淪omething like this helps to put some of the power back in your hands,鈥 she says.

The medical community鈥檚 adoption of 3-D printing is triggering big changes. Also called additive manufacturing, 3-D printers make items by layering metal, plastics, wood, and other materials.

While 3-D printing has been used in the auto industry for rapid prototyping since the 1980s, and more recently for controversial DIY handguns, its medical uses are exploding in a way reminiscent of the glory days of American manufacturing.

It鈥檚 helped bring medical devices to market faster by fashioning prototypes quickly, make life-changing and life-saving implants tailored to an individual鈥檚 own anatomy, plan and perform surgery like knee replacements and Jonah鈥檚 procedure using patient-specific models, and teach doctors in training.

In short, 3-D printing is unique: It can be used to manufacture intricate items that would be impossible to make any other way.

Mike Moceri, CEO of Manulith, a 3-D printing product development company at TechTown in Midtown, taught himself the process and built his own 3-D printer after his freshman year at DePaul University. He dropped out during his junior year and started a 3-D printing store in Chicago before moving back to his hometown to establish Manulith.

鈥淭here鈥檚 really no university that teaches 3-D printing,鈥 he says. While that may be a slight overstatement, it鈥檚 definitely still an emerging technology.

As far as the medical community goes, 3-D printing of replacement organs and human tissue to test new drugs remain just barely science fiction. But custom-made patches to fill gaps in skulls and DIY hand prostheses are science fact.

So, too, are dissolvable splints made at the University of Michigan for babies whose airways collapse. U-M鈥檚 Dr. Glenn Green, a complex airway reconstruction specialist, has implanted several of these splints, designed to help until the cartilage in a baby鈥檚 trachea can develop and stay open on its own.

Green鈥檚 colleague Dr. Scott Hollister, who 3-D prints the babies鈥 splints, also made a dissolvable prosthetic jawbone for a man in Milan that was seeded with 鈥済rowth factor鈥 鈥 a substance to stimulate cellular growth. The idea is that, as the man鈥檚 own replacement bone grows, the prosthesis will dissolve, just like the babies鈥 splints.

Green and Hollister have also collaborated on a permanent trachea splint for adults with a life-threatening autoimmune disorder that weakens their airway cartilage.

鈥淚f somebody鈥檚 going to die immediately we can put it in,鈥 Green says.

Hollister, who鈥檚 been 3-D printing since 1996, also has ongoing pre-clinical studies for replacement ears and noses; arm, leg, and facial bones; and devices for spinal fusion. 鈥淚n the future, we would print a scaffold and seed it with cells,鈥 he explains, referring to a person鈥檚 own stem and growth factor cells.

Meanwhile, Henry Ford Hospital is taking some of the guesswork out of catheter-based aortic valve replacements by printing 3-D models of patients鈥 hearts that doctors use to determine a more exact valve size.

鈥淲e simply don鈥檛 have adequate sizing tools,鈥 says Dr. William O鈥橬eill, medical director of Henry Ford鈥檚 Center for Structural Heart Disease.

That鈥檚 important because an undersized replacement valve can leak and lead to heart failure, O鈥橬eill explains. Even a correctly sized implant could interfere with other structures inside the vital organ and block blood flow if not placed correctly, he explains. In addition, knowing in advance what to expect can speed the procedure and reduce a patient鈥檚 time under anesthesia.

O鈥橬eill says Ford plans to formally study using old measuring techniques vs. using 3-D models.

鈥淚f it works for us we want to demonstrate it so other people could use it,鈥 he says.

At Beaumont, Chaiyasate has another use for 3-D printed models, in addition to enlightening patients and parents: He uses them to plan his surgeries. Lines he鈥檚 made with permanent marker on his 鈥渓ibrary鈥 of models show where he cut the skull during complex microsurgeries on children and adults. In surgeries more intricate than Jonah鈥檚, whose skull was cut in two, some sections are also marked with letters, like misshapen Scrabble tiles, to help him reassemble the skull.

鈥淐ould we do it without 3-D?鈥 Chaiyasate asks. 鈥淚 think we could, but it would be less precise. In the past, we just eyeballed it and did a lot of guessing.鈥