Printing New Life
How 3-D Printers are Changing Medicine Forever
Time for a Change
Imagine, if you will, that you go to your doctor for a routine check-up and he tells you there’s something wrong with a blood test. Your liver appears to be failing, and you need a transplant. You’re terrified, even more so at how long it may take to get a donor organ.
According to federal data, the median wait time for a donor liver in the United States is 361 days. Most patients will spend between one and two years waiting for their organ.
If you live long enough to receive your transplant — and 18 Americans die every day waiting for an organ — there’s still a chance that your body will reject your new organ. You’ll also have to spend the rest of your life on immunosuppressant drugs that prevent your body from attacking the donor organ but make you more susceptible to other infections. This is how the system for organ transplantation currently works and has worked for decades, but a new solution to an old problem may lie in something that sounds like it’s straight from a science-fiction novel: 3-D printers.
Dr. Faiz Bhora of St. Luke’s-Roosevelt Hospital Center in New York has been researching a way for organs made from stem cells and 3-D printers to be transplanted into living patients. He and his research team have been using 3-D printers to create artificial scaffolding for tracheas, which then are coated in stem cells that grow into the different parts of the trachea. Effectively, they are printing a new organ.
Printing a trachea for transplant is much more difficult than printing an organ such as a liver, Bhora said, because livers consist mostly of one kind of cell. Tracheas have a more complex structure and function.
Using 3-D printers to make a liver for transplant may happen sooner than printed tracheas could be available for use in humans. Another thing that might hasten the arrival of printed-liver transplants is that transplants can replace a part of a damaged liver, not the whole thing. “You’re not printing a whole organ, so it’s conceivable that within the next few years” doctors could transplant 3-D printed livers, Bhora said.
Bhora is optimistic about what the future holds for 3-D printing in medicine, especially when it comes to waiting lists for organ transplants. “I know it sounds like science fiction, but you’d basically have your organ 3-D-printed in advance,” he said.
The body is just a system of parts that make up a whole entity. In that regard, it’s much like a computer. When a major component of a computer breaks—the motherboard, say — people often buy a new part instead of fixing the broken one because it’s just more cost effective. Bhora said this is how organ transplants will work in the future. Instead of lengthy, risky surgeries to repair damaged organs, it will be safer and cheaper to replace them.
Doctors are already using the precision of computers and 3-D printers clinically. Dr. Michael Egnor, director of pediatric neurosurgery at Stony Brook Children’s Hospital, recently used a 3-D-printed model to help reconstruct the skull of an infant.
The baby, Gabriel Dela Cruz, was born with erect craniosynostosis, a condition that transforms one or more parts of an infant’s skull into bone, distorting the skull’s growth pattern after birth. To fix this condition, surgeons traditionally performed reconstructive surgery and put pieces where they thought they should go.
“The operating involved removing the bones at the front of the skull and the face and sort of remodeling them and then putting them back on,” Egnor said.
But by using a precise model of Gabriel’s skull made by a 3-D printer, Dr. Egnor and his colleagues could reconstruct the skull much more accurately.
Egnor said he and his colleague Dr. Elliot Duboys, a plastic surgeon, had the idea of contacting Medical Modeling Inc. based in Golden, Colo. to make a surgical template for doctors to use.
The company took a CAT scan of Gabriel’s skull. Based on that image, they used computer software to create a template of what the skull should look like after the deformities had been corrected. Gabriel’s surgeons used that template to position the parts of Gabriel’s skull during its reconstruction.
“It adds a lot of precision to the operation,”Egnor said.
The template also shortened the operation and eliminated the need for doctors to make any additional modifications to the pieces of bone after the initial cuts had been made.
Too Long a Wait
One of the most serious problems patients in need of a transplant face is the waiting time. According to data provided by the U.S Department of Health and Human Services, as of May 8, 2014, 122,551 people were waiting for an organ transplant. Someone is added to that list every 10 minutes.
Time spent waiting for a donor organ varies drastically. It can be as little as 100 days or as many as a thousand, or roughly three years. That’s time many patients don’t have. Bhora said that fabricating human organs could eliminate the need for organ donors entirely.
Peter Brooke, a medical student at Norwich Medical School in the United Kingdom, is also optimistic about the ability to use 3-D printers to manufacture human tissue, but thinks that there are some very large hurdles to cross before the technology can reach its full potential. “if you’re printing cells or tiny ducts, like liver ductules, or kidney nephrons, they are micrometers wide,” said Brooke. “No 3-D printer can print with that detail or precision yet.”
Another problem that faces transplant recipients patients is the struggle following the transplant. The body treats a transplanted organ as a foreign body and will work to destroy it for the rest of the patient’s life.
To combat this, patients take drugs that suppress their own immune system in order to prevent rejection. In reality, the body never completely accepts a donor organ. It just loses the battle to kill it.
It’s not uncommon for the body to completely reject an organ long after the transplant has taken place, even as long as 10 years, Bhora said.
“If the cells are from your own body, then there’s really no significant chance of rejection,”said Bhora. “That’s one of the aspects that’s really driving the whole field, is that you do away with the whole immune-suppression aspect of it, which is what significantly restricts the lives of transplant patients.”