Planning the new bone shape
There are various reasons why there will be a need for a patient-specific implant. Most of the time, we will need to restore as well as possible the shape of the anatomy prior to a trauma that destroyed the bone or prior to a surgical bonectomy.
In-vitro studies are routinely done to assess the outcome of digital repairs compared to the initial shapes. Typically, dry skulls and digital models are used for this. But we find it always more powerful and satisfying to compare our digital designs with what the patient’s anatomy truly was before needing a repair.
The problem with this is that it is not always possible to have access to a high-resolution scan of the patient prior to a trauma or a bonectomy. Indeed, there is no obvious reason why you would have a previous scan of your head. “Just in case the original shape of my head is ever needed”? That would be a very unusual data to have.
Sometimes though, there is some sort of 3D information available about the shape of the head that dates prior to when the repair is needed.
Ed had a low-resolution CT scan prior to having a craniotomy. He also had a high-resolution CT scan post-craniotomy and we used this scan to plan the repair, the new shape to be the basis of the final shape of his implant. We used the illustration below to show how close our design was from Ed’s shape prior to his craniotomy.
The resulting implant was really good but for us, Ed’s opinion is what really matters.
“Thank you very much for your patience and help. You have thoroughly answered all of my questions and have been very kind. You have gone well beyond the call of duty to help me and the team of health care professionals supporting me during this process. […] My surgery went very well and I am extremely happy with the implant. […] Thanks to your well designed product and my surgeon, my skull looks symmetrical again. Your implant has changed my life.”