3D Printing Used To Model Teen's Skull

Parker Turchan, a 15-year-old from Portage, Michigan kept complaining about a stuffy nose and mild cold. Further diagnosis revealed he had a rare type of tumor in his nose and sinuses that extended through his skull near his brain.

“He had always been a healthy kid, so we never imagined he had a tumor,” says Parker’s father, Karl. “We didn’t even know you could get a tumor in the back of your nose.”

The high school sophomore was then referred to the University of Michigan’s C.S. Mott Children’s Hospital. After CT scans the doctors discovered the tumor extended so deep into the skull that it could not be detected by regular endoscopy.

Parker’s rare and aggressive tumor is known as juvenile nasopharyngeal angiofibroma, a mass that grows in the back of the nasal cavity and predominantly affects young male teens. Dr. Mott says he sees only a handful of cases each year.

“Parker had an uncommon, large, high-stage tumor in a very challenging area. The tumor’s location and size had me question whether a minimally invasive approach would allow us to remove the tumor completely,” he said.

Mott pediatric head and neck surgeon David Zopf, M.D. said they needed the best depiction of the tumor’s stretch in order to perform a successful surgery.

For the solution, the team turned to the innovative approach of 3-D printing, which enabled them to craft a 3-D replica of Parker’s entire skull.

This polylactic acid model of the skull helped doctors simulate the coming operation and also allowed family members to have a look at the tumor and envision what lies ahead.

The tumor inside Parker’s nose had two large parts – one about the size of an egg and the other the size of a kiwi. The mass sat right in the center of the craniofacial skeleton below the brain and next to the nerves that control eye movement and vision.

Parker’s dad praised the 3-D methodology used to aid in his son’s surgery. He said:

“We were obviously concerned about the risks involved in this kind of procedure, which we knew could lead to a lot of blood loss and was sensitive because it was so close to the nerves in his face. It was pretty impressive to see the model of Parker’s skull ahead of the surgery. We had no idea this was even possible.”

Dr. Zopf, working with Erin McKean, M.D., a U-M skull base surgeon, was able to completely remove the large tumor. Kyle VanKoevering, M.D., and Sajad Arabnejad, Ph.D., aided in model preparation.

The day before surgery, doctors blocked of the blood supply to the tumor by using preoperative embolization to decrease loss of blood. They then detached a large portion of the tumor endoscopically and remove it through the mouth. The remaining mass under the brain was removed through the nose.

Pictures taken during and after Parker’s surgery were compared with pictures from the model: they were amazingly identical.

The groundbreaking 3-D printing technology isn’t new, though this is the first time it has been used for such an application. Dr. Zopf and the team at Mott have used 3-D printing for almost five years.

In the past, doctors at U-M have used 3-D printed splints to save the lives of babies with severe tracheobronchomalacia - a condition that causes the windpipe to periodically collapse and prevent normal breathing. 3-D printing of a fetus enabled Dr. Mott to plan for a potentially complicated birth. 

“We are finding more and more uses for 3-D printing in medicine,” Zopf says. “It is proving to be a powerful tool that will allow for enhanced patient care.”

Dr. Zopf believes their team approach established at the University of Michigan between otolaryngology and biomedical engineering can rapidly design and produce printed models at a very low cost.

“Michigan is one of only a few places in the nation and world that has the capacity to do this,” he said.