Because of a condition that put huge pressure on his airways, 18-month-old Garrett Peterson of Utah had been tethered to ventilators and lived in hospitals since he was born. He was in mortal danger because his airways had collapsed, and even on their highest settings, the ventilators could not prevent his breathing from stopping several times a day.

Now, thanks to splints that surgeons at the University of Michigan's C.S. Mott Children's Hospital have implanted in his airway, thus saving his life, Garrett can go home and gradually be weaned off the ventilators.

Garrett's condition is called tetralogy of Fallot with absent pulmonary valve, and in his case, it had developed into severe tracheobronchomalacia, or softening of his trachea and bronchi, to the point that the airways had collapsed to the size of small slits.

Severe tracheobronchomalacia is very rare and affects about 1 in 2,200 newborns. Most grow out of it by age 2 or 3, but it can be misdiagnosed as asthma that does not respond to treatment. Severe cases, like Garrett's, are about 10% of that number.

3D imaging and printing technology used to make biodegradable splints

From a medical standpoint, the remarkable thing about Garrett's story is that the life-saving implants were made using CT scanning and 3D imaging and printing technology to produce bioresorbable splints of the exact shape to ensure a snug fit in the little boy's airways.

And not only this, but the devices will gradually biodegrade harmlessly in the child's body, as his trachea and bronchi strengthen so he can breathe on his own without ventilation.

In fact, this is only the second time this technology has been used to save a child's life - both times at the same hospital. The first time was in early 2013, when a 3D-printed splint of a windpipe saved the life of another toddler, Kaiba Gionfriddo of Ohio, whose life was also threatened by tracheobronchomalacia, causing his airway to collapse.

The devices were developed at the University of Michigan by Glenn Green, associate professor of pediatric otolaryngology and Scott Hollister, professor of biomedical engineering and mechanical engineering and associate professor of surgery.

The video below details Garrett's story, his surgery and the team's successful efforts:

Team used emergency clearance provisions from FDA to make/implant splints

After reading about Kaiba's story, Garrett's parents, who were desperately running out of options to save their son's life, contacted the team at Michigan, who used provisions for emergency clearance from the Food and Drug Administration (FDA) to create a tracheal splint from a biopolymer called polycaprolactone to implant into the little boy's airway.

Speaking to the press about Garrett's condition, Prof. Green says, "It was highly questionable whether or not he would survive."

Prof. Hollister made the custom-designed, custom-fabricated splints using high-resolution imaging and computer-aided design. He started with a CT scan of Garrett's trachea and bronchi, then used an image-based computer model with laser-based 3D printing to produce the splint.

Prof. Green assisted Richard G. Ohye, head of pediatric cardiovascular surgery at C.S. Mott, to perform the operation at the end of January 2014. The procedure involved sewing the devices on two spots of the baby's airway.

They sewed the splints around Garrett's left and right bronchi to widen the airway and keep it open so it would grow correctly. As Garrett grows, over the next 3 years or so, the splint will biodegrade and be reabsorbed in his body. Over that time, his trachea should remodel and grow into a healthy state.

Surgeons are 'very optimistic'

Prof. Green says he knew the splints were working when during the surgery they saw Garrett's lungs begin to inflate and he was able to ventilate both lungs. "I'm very optimistic for him," he adds.

Garrett will still need to stay on the ventilator, but as he gains strength to breathe on his own, he will gradually need it less and less. It is already on less than a quarter of the pressure it was on before the operation, and he is able to go for short periods completely off it.

Prof. Hollister says:

"It is a tremendous feeling to know that this device has saved another child. We believe there are many other applications for these techniques, but to see the impact living and breathing in front of you is overwhelming."