Educational 3D-Printing

Segmented Liver Model: I segmented this life-sized model of a liver using MeshMixer. I reverse extruded holes for rare earth magnets to be inserted to keep segments together, and 3D printed this model of the liver. The model is separated into segments as per the Couinaud Classification system, to demonstrate the sections of the liver that possess their own vascular inflow / outflow and biliary drainage.

Distal Radius Fracture Project: Patients admitted to Cooper University Hospital (Level 1 Trauma Center) for Distal Radius Fractures are considered for this project. Before the patient undergoes surgery for fracture repair (typically one day after admission), the patient undergoes a CT scan of the wrist, the wrist is segmented on TeraRecon and exported as a 3D object file, and the model is 3D printed and used for pre-operative planning. The model below demonstrates a transverse distal radius and transverse distal ulna fracture, connected by a piece proximally to demonstrate approximation of the distal segments. We were awarded a $5000 grant from the American Society for Surgery of the Hand to expand this initiative.

Abdominal Aorta Model with Major Branches: I designed this model using Fusion360 to help medical students practice insertion of guidewires in interventional radiology. The guidewire would start in the external iliac artery in this model, similar to real procedures after gaining femoral access. Then the guidewire can move upstream, and into either the branches of the inferior mesenteric, superior mesenteric, or celiac arteries. The celiac trunk in the model also branches into the common hepatic, splenic, and left gastric arteries. A catheter can then be placed using the guidewire. This model has been 3D-printed with translucent filament to visualize catheter / guidewire insertion, and has been used successfully by the medical students for practice.

Facial bone fracture: A colleague was in an unfortunate bike accident. On CT, he was found to have a right zygomaticomaxillary complex fracture. He was given access to his thin slice CT scan of facial bones. He requested I create a 3D-printed model of his facial fracture. I segmented the DICOM files and prepared the file for 3D-printing. The middle image below best characterizes his fracture. This demonstrates how visualizing facial fractures in a 3D model can help improve spatial understanding of complex facial fractures.

Trachea Model: I was challenged by an interventional pulmonologist to create a model of a trachea from CT of the chest that could be used to practice placing endobronchial stents. Our institution does not have the lung segmentation package which could automatically define the tracheal walls and lumen, so I designed a workaround.

I used TeraRecon's auto-segmenting tool, which could only pick up the tracheal lumen as a solid object file. I then make a copy of the file, and use erosion / dilation to create thinner / thicker object respectively around each airway lumen. I subtract the smaller object from the larger object. The result is a model with the same intralumenal volume /  contour as the original airway (shown below). The downside is the tracheal wall is not completely accurately represented, but for the purposes of practicing endobronchial stent placement, the lumen was the most important part.