Cancer treatment in a dog with guides and implant – helped with Blender
Johnny Uday writes:
This is Lulu, a dog in Quito Ecuador diagnosed with a Melanosarcoma inside her mouth.
The Veterinary surgeons at University of San Francisco Veterinary Hospital contacted biomodeler Johnny Uday to design surgical guides for excision of the tumor, and also for designing an implant to fill the hole after resection.
Dr Johnny Uday decided to try a biocompatible plastic for making this job, and used blender to model the guides and implant.
The surgery was a success and the use of bio compatible plastic instead of the expensive titanium could represent an humongous economical advantage for uses in human and veterinary medicine.
Caution: contains some explicit imagery of an operation on an animal.
That’s amazing, so happy to see Blender being used for good:)
Nice! Do you sacrifice anything from using plastic instead of a bone graftable metal? And are there also other gains besides low cost and easy custom-fit fabrication?
I’m not entirely sure they didn’t use metal for the permanent implant…
I’ve seen dogs being euthanized for smaller masses. The location is tricky because there are significant forces acting on the bone, and just cutting it out would leave a compromised structure. The alternative is to use “analogue” modeling techniques, but then you often have to adjust the implant during surgery.
I think the first object/implant is a guide for the saw. There the plastic wouldn’t matter as much. But due to the screws being driven into the same previously defined holes (maybe even in a prior surgery?) you get a sort of “bone GPS”. This saves a lot of bone tissue because a surgeon would otherwise have to extract a wider margin from the tumor to be sure to get everything out.
Hi, Yes the first object is a surgical guide for the saw and drilling holes which will make a perfect fit for the implant during surgery reducing time and giving a more accurate result.
Yes, Actually in Ecuador we don’t have Titanium 3D printers, so using an affordable 3D printer with bio compatible plastics makes everything not just cheaper, but we could get this printed in a couple of hours instead of waiting about 2 or 3 weeks for the arrival of an implant printed in States or Europe. Plus the bio compatible plastic also allows grafting of other tissues on it. However this is not ideal for every single case, in some cases you cannot avoid using titanium, but in cases like Cranioplasties this method and material could be of great use.
Hm unfortunately not very detailed explanation…. It’s from Quito so it should be Spanish? The medical terms are mostly self-explanatory. Questions left are how they built the (two?) custom implants. 3D printed metal maybe?
It looks to me as if the first implant is meant as a guide to extract the tumor and then the second implant is inserted into the same place using the same screw placement.
I hope I can find a paper on this…
Hi, yes that is right, the first one is a surgical guide, that is for guiding the saw and the drilling holes into the exact location where the implant will be placed. Allowing the surgeon for a faster and more accurate procedure. We are working on a paper about this and other cases, hopefully finished in a couple of months.