Creating Cranial Implants with CAD 

After suffering an accidental blow to the head during a soccer match, Jiahone Guo's brain began to swell. By the time he arrived at the hospital, he was in a coma and had to have a quarter of his skull removed to allow the swelling to subside.

The odds of surviving such a trauma were about 50-50, but traditional skull grafts can lower these odds further by increasing the risk of infection. But new implants created through 3D imaging and modeling software are helping to improve those odds, just as they did for Guo.

Made of polyether ether ketone (PEEK), biomedically optimized thermoplastic polymer, and developed by MedCAD through the use of Geomagic's 3D modeling software, Guo’s cranial implant was designed from CT scans, which saves time and reduces risk during surgery.

The process, known as AccuShape, allows for faster digital design and eliminates errors that come from manually sculpting an implant out of acrylic or another biomedical material, which used to be the standard for these implants.

Since PEEK is the closest biomedical material there is to natural bone, the implants now are strong, light, and not prone to infection. AccuShape also leads to a better aesthetic result for the patient.

To create the prosthetic, MedCAD takes CT data as well as paperwork to build a 3D model through Geomagic Freeform software. This allows surgeons to explore the surgery from every angle so they can pinpoint problem areas before they arise.

To create the AccuShape workflow model, an STL file (a standardized format for computer-aided design) is uploaded into Geomagic Freeform, which enables the implant to be digitally sculpted as if it were clay. Geomagic Sensable Phantom is integrated to provide tactile feedback and enabling the design engineer to feel surfaces, edges and topology.

MedCAD also uses Geomagic Studio software, which creates complex surfaces from STL data, allowing for accurate digital manufacturing of the implant – something typical CAD software is unable to offer.

Tying the process together is proprietary in-house software and procedures developed by MedCAD. Depending on the material required and how the final piece will be used, implants may be manufactured using either a 3D printer or a computer numerical control (CNC) machine. For the time being, CNC machines are required for PEEK implants, since 3D printing with PEEK material has not yet been approved by the FDA.

Full story at Design World