Frank Bonelli is an American practitioner, board certified in Diagnostic Radiology, with CAQ in Neuroradiology. He is fortunate to have access to a variety of CT and MRI scans. He has several printers: a Prusa i3 MK2, a Prusa MK3, a SeeMeCNC Artemis 300 (great for large long prints like femurs) and a Elegoo Mars resin printer.
He has really been interested in how close “off the shelf” prosumer printers can accurately print medical models. He occasionally teach students how to process and ultimately print from imaging, and he has written up some guides and tricks (such as support placement) to make the printing process successful.
What motivated you to work with 3D printing?
My introduction to 3D printing was entirely accidental. My youngest son, a Sophomore in high school at the time, had always wanted a printer to print “stuff”, so we finally settled on a Prusa i3 MK2 kit. We built it together, but he really lost interest after the building phase, so there it sat.
I printed out a few gadgets for my cameras and some figurines, but I wasn’t really getting into the 3D print groove. Then I thought, what if I can print something from a CT scan? I started simple, with a CT scan of an elbow. I learned to segment with 3D slicer, learned Meshmixer for post-processing, and simplify 3D to make the final product. Suddenly, I was printing everything I could get my hands on. It has become a mild addiction and my home and work office contain hundreds (literally) of prints of a variety of normal and pathologic body parts.
I am working on a lot of little projects. Some projects, including the brain keychains for my nieces and nephews
Which 3D model do you consider is your best contribution so far and why?
Unexpectedly, it’s the cervical spine model with intervertebral discs. Not sure why it’s so popular. Maybe because it makes a great anatomical teaching model.
How is 3D printing useful in your daily work?
I don’t directly apply 3D printing in my daily work. Occasionally, I will print up a complex case (say a complex fracture) for a colleague because they are interested and know I print, but not for clinical planning.
I believe the real usefulness is from an education standpoint. Segmenting a model and examining the resultant 3D print really hones ones’ anatomic skills. Complex fractures, particularly of the face, take on a new meaning beyond looking at a 3D image on a computer screen when one can hold the model in ones’ hands. In addition, one can print a huge variety of both normal and anatomic pathology. It’s cool to see how a spine with ankylosing spondylitis really looks.
What do you recommend to whom is starting in the 3D medical printing world?
You’ll need access to a 3D printer and .nrrd CT files if you want to start at the beginning of the process.
3D slicer (for segmentation) is free, and once you learn it, is relatively easy to use. Meshmixer (to refine the model’s mesh) is free as well. Finally, one needs a good program to accurately convert .stl files to gcode.
Start small and easy: printing normal simple bones like portions of the elbow or knee are a good first start. Learn to segment the bones quickly and accurately, and learn the quirks of segmentation and how they apply to printing. Then move on to something more complex (print a fracture – how will you demonstrate the fracture fragments in a print when they are displaced?). Finally, move on to complex structures, learning to segment soft tissue, bone, etc. Experiment with different print materials. For non-treatment planning purposes (education or just because it’s fun), you can print virtually anything using an off the shelf printer (like a Prusa) and obtain a very realistic, accurate model.
A Radiologist who´s passionate about AI and imaging in any form. From x rays, ultrasound to CT, MR and 3d printing. Likes photography, music, and video games.