A new method of 3D printing an anatomically accurate replica of the human liver is now helping to guide surgeons during tricky procedures.
The 3D-printed replicas, which are made of transparent material threaded with colored arteries and veins, could help surgeons prevent complications when performing liver transplants or removing cancerous tumors, researchers said.
"We provide the surgeons with a physical model that is 100 percent identical to what they will encounter in surgery when they operate," said Dr. Nizar Zein, the chief of hepatology at the Cleveland Clinic in Ohio. "It takes away some of the potential surprises that will be found at the time of surgery."
The new liver replica could also be used to train medical students in the techniques needed for surgery, Zein said. [In Images of the 3D Printed Livers ]
While reading a newspaper article about 3D printing, Zein realized that the technique could help make surgeries simpler. Before complicated liver surgeries, doctors usually look at a magnetic resonance image (MRI) or a computed tomography (CT) scan to visualize the liver and plan the operation.
But these 2D images don't provide true visual guidance during surgery. There are three main veins in the liver, and doctors often go into surgery unsure exactly where these blood vessels are located. Inadvertently cutting them can lead to "a disaster outcome," Zein told Live Science.
To create the artificial livers, the researchers combine the MRI and CT scans that patients have already undergone, and then recreate the 3D shape of the organ. A study published last month in the journal Liver Transplantation confirmed that the models are anatomically accurate in terms of volume and location of vessels in the liver.
Using these models, the team creates the 3D-printed organs using a transparent polymer, then dyes the main blood vessels and the bile ducts.
So far, the team has used such livers in about 30 cases. In a few operations so far, surgeons changed their plan for the surgery based on the simulated organs, for instance, after realizing that cancerous liver tumors were too close to certain veins to completely cut the growths out.
"We believe we actually avoided some complications this way," Zein said.
The researchers are now developing similar methods to guide complicated surgeries, such as hand and face transplants, and pancreatic tumor removals, Zein said.
They are also investigating a way to integrate organ models into the global positioning systems (GPS) that currently guide surgeries. These GPS tools determine the exact location to cut and the safe margins for a surgery. By improving the models of the organs that these systems use, the hope is that the GPS will become even more accurate, Zein said.