Feature | Medical 3-D Printing | February 22, 2017

Children's Hospital Los Angeles Cardiologist Creates Modified Stent for 18-month-old Using Printed 3-D Model

Team uses CT heart scans to create 3-D model of obstructed pulmonary artery to fashion a smaller stent

Children's Hospital Los Angeles, CHLA, Frank Ing, 3-D printed model, pulmonary artery

Pediatric interventional cardiologist Frank Ing, M.D., chief of the Division of Cardiology and co-director of the Heart Institute at Children’s Hospital Los Angeles. Photo courtesy of Children's Hospital Los Angeles.

Children's Hospital Los Angeles, CHLA, pediatric stent, 3-D printed model, Nate Yamane

Children's Hospital Los Angeles doctors practiced customizing a stent to fit into Nate's 9-millimeter narrowing using this 3-D printed model (branch on left). The model also recreated an existing stent in Nate's other pulmonary artery branch (top right). Photo courtesy of Children's Hospital Los Angeles.

February 22, 2017 — When Children’s Hospital Los Angeles cardiologists found evidence that a portion of Nate Yamane’s pulmonary artery they had repaired once before was again narrowing, pediatric interventional cardiologist Frank Ing, M.D., decided they needed to insert a stent to keep the right artery open.

But due to the size of the narrowing, about 9 millimeters, doctors needed to customize the stent to fit into the smaller space and they wanted to perfect their measurements before the actual procedure. Using computed tomography (CT) scans of Nate’s heart, they created a 3-D printed model of the obstructed region. Ing was then able to fashion a smaller stent to fit precisely into the narrowed artery in the model.

"I have to say, the 3-D model was very helpful because it gave me confidence that [the size of the stent] was going to work," said Ing.

Born in June 2015 with tetralogy of Fallot (TOF) with pulmonary atresia, the 7.1-pound infant Yamane had trouble breathing shortly after birth. The cause: a genetic abnormality resulting in heart defects that obstructed his pulmonary artery, preventing blood pumped by the heart from flowing into the lungs.

He was rushed to Children’s Hospital Los Angeles from a South Bay hospital in critical condition. Pulmonary atresia — a more severe version of TOF — occurs when the pulmonary artery fails to form properly in utero, prompting the human body to grow collateral arteries that redirect blood around the obstruction and to the lungs (a typical development with these types of blockages). About one in 10,000 children are born with this congenital heart defect.

“Imagine blood flowing in the artery like cars on the freeway, and it’s blocked. Cars exit and find an alternate route to its destination; blood does the same, and in this case finds its way through collateral vessels to the lungs,” explained Ing, the chief of the Division of Cardiology and co-director of the Heart Institute at Children’s Hospital Los Angeles.

But after birth, those vessels need to be rebuilt quickly or the heart will fail. Using a surgical technique called unifocalization, surgeons can repair the vessels by sewing them together. “We use whatever the body gives us,” explained Ing, a professor of clinical pediatrics and medicine at the Keck School of Medicine of the University of Southern California.

A month into his young life, Nate had undergone two open-heart surgeries and a catheterization procedure, but doctors were not done. In December 2015, Nate's pulmonary arteries were found to be narrowed in both the right and the left branch. At the time, a team led by Ing was able to use a balloon to open the right side. However, to keep the left section open they had to insert a stent, specially modified using a technique developed at CHLA, to fit the narrowed portion of the child's left pulmonary artery (about 15mm). Stents do not normally come that small, but by carefully cutting their smallest existing stent and folding it back upon itself, Ing tailored a functional custom stent that worked perfectly and did not jut out needlessly into other areas.

Almost immediately, Nate saw marked improvement in blood flow, including a healthy drop in blood pressure. Still, in the coming months, he gained little weight and had to grow bigger and stronger before considering another procedure. “We did physical therapy and tried to fatten him up,” said Nate’s mother, Courtney.

Watch the VIDEO "Use of 3-D Printing To Help Guide Structural Heart Intervention."

On Jan. 19, 2017, Ing inserted the second, even smaller stent into Nate’s right pulmonary artery in CHLA's catheterization lab before an international audience of cardiologists watching on a live video feed at the Pediatric and Adult Interventional Cardiac Symposium in Miami. Using the stent that was modified in advance to the same specifications in the model, Ing and his team were able to open up Nate's right pulmonary artery, with successful results; Nate’s oxygen levels improved overnight.

In the months and years ahead, Nate will need additional surgeries, but his weight is up to 21.5 lbs., and he’s eating better and getting stronger. “He’s rolling around with energy and even took his first baby steps,” said Courtney, who also has a four-year-old at home. “There’s a big difference and a lot of improvement. We’re going in the right direction.”

Read the ITN feature story "The Future of 3-D Printing in Medicine."

For more information: www.chla.org

Related Content

SimonMed Deploys ClearRead CT Enterprise Wide
News | Computer-Aided Detection Software | September 17, 2018
September 17, 2018 — National outpatient physician radiology group SimonMed Imaging has selected Riverain Technologie
Siemens Healthineers Announces First U.S. Install of Somatom go.Top CT
News | Computed Tomography (CT) | September 17, 2018
September 17, 2018 — The Ohio State University Wexner Medical Center in Columbus recently became the first healthcare
The CT scanner might not come with protocols that are adequate for each hospital situation, so at Phoenix Children’s Hospital they designed their own protocols, said Dianna Bardo, M.D., director of body MR and co-director of the 3D Innovation Lab at Phoenix Children’s.

The CT scanner might not come with protocols that are adequate for each hospital situation, so at Phoenix Children’s Hospital they designed their own protocols, said Dianna Bardo, M.D., director of body MR and co-director of the 3D Innovation Lab at Phoenix Children’s.

Sponsored Content | Case Study | Radiation Dose Management | September 07, 2018
Radiation dose management is central to child patient safety. Medical imaging plays an increasing role in the accurate...
Carestream Releases Second-Generation Metal Artifact Reduction Software for OnSight 3D Extremity System
Technology | Computed Tomography (CT) | September 06, 2018
Carestream Health has started shipping a new software version for its Carestream OnSight 3D Extremity System that...

Image courtesy of Siemens Healthineers

Feature | CT Angiography (CTA) | September 06, 2018 | Dave Fornell
There have been a few big, recent advancements in cardiac computed tomography angiography (CCTA) imaging technology....
Key Patient Preparations for a CT Scan
News | Computed Tomography (CT) | September 05, 2018
The Center for Diagnostic Imaging (CDI) in Miami recently released a list of important preparations patients should...
iSchemaView RAPID Technology Now Installed in More Than 500 Stroke Centers
News | Neuro Imaging | August 27, 2018
iSchemaView announced that more than 575 stroke centers in 22 countries have selected the RAPID advanced imaging...
Doctor-Patient Discussions Neglect Potential Harms of Lung Cancer Screening
News | Lung Cancer | August 15, 2018
August 15, 2018 — Although national guidelines advise doctors to discuss the benefits and harms of...
ACR LI-RADS Steering Committee Releases New Version of CT/MRI LI-RADS
News | Clinical Decision Support | August 13, 2018
August 13, 2018 — The American College of Radiology Liver Imaging Reporting and Data System (LI-RADS) steering commit
Aidoc Receives FDA Clearance for AI Detection of Acute Intracranial Hemorrhage
Technology | Clinical Decision Support | August 08, 2018
Aidoc announced that it was granted U.S. Food and Drug Administration (FDA) clearance for the first product of its...
Overlay Init