The Boss of the House

"We called her our little unicorn because she had this bump on her head, but it would have killed her. It's pretty amazing what they did for my girl."
"Her head looks great, other than her crooked ear. Patches is now cancer-free."
"They felt she could recover from this. And to be part of cancer research was a big thing for me -- if they can learn something from animals to  help humans, that's pretty important."
Danielle Dymeck, Williamsport, Pennsylvania

"Our hope is this is something that could be more widely available on a broad scale. It went very well."
"[We had to create a] cutting guide [to follow during surgery]. There's very little room for error."
"We we're talking less than two millimetres or else the plate wouldn't fit."
Michelle Oblak, veterinary surgical oncologist, University of Guelph Ontario Veterinary College

Patches, a nine-year-old dachshund from Willamsport, Pa., is shown before surgery for a brain tumour that eventually grew through her skull. The Canadian Press

The plate that Dr. Oblak referred to was a custom-made titanium skull cap blueprinted to fit a dog. And the dog was Patches, a nine-year-old Dachshund with a brain tumour the size of an orange. As it grew, it eventually emerged right through her skull. Had it not been treated by surgery, that tumour would have been fatal. Patches required about seventy percent of her skull to be removed and replaced.

The surgery that Patches underwent is not entirely new. Veterinarians in the United Kingdom have performed quite similar surgery, but on a smaller scale. What is quite different about Patches' procedure is that 3D-printing technology was involved. Dr. Oblak, a researcher in Guelph, has studied the use of 3D-printing technology specifically for dogs. She explained that up to the time that Patches underwent her surgery -- the first of its kind using 3-D printing technology -- a different type of procedure prevailed.

On those other, earlier occasions, a tumour along with part of the skull would be surgically removed and while the animal was still anaesthetized, the surgeon would fit titanium mesh into place, an imprecise, costly and lengthy procedure, she stressed. The process that Dr. Oblak has pioneered is entirely new, where a 3D-printer is used to create a custom-made titanium skull cap that fits into place more accurately.

Danielle Dymeck, Patches' human, described the appearance of a small bump Patches wore on her head for years. And then it began to grow months earlier, in an aggressive manner. The veterinarian who normally looked after Patches mentioned to Dymeck that Cornell University, known for its veterinary program might help. A veterinarian at the university contacted Dr. Oblak, and that began Patches' journey to ridding her of the cancerous tumour and giving her a new lease on life.

Patches after the operation to replace part of her skull with a titanium implant. (Canadian Press)

A CT scan was taken, to provide an image of Patches' head and tumour. With the use of a number of different software programs on that image, Dr. Oblak and her team cut out the tumour digitally along disease-ridden portions of Patches' skull. They turned then to mapping out where a 3D-printed replacement would look like, along with where holes for screws should be located to hold the titanium skull plate in place.

The digital blueprints were forwarded on to ADEISS, a medical-grade 3D-printing company located in London, Ontario. There, a customized titanium skull cap was produced for Patches. With the aid of the "cutting guide" that Dr. Oblak had created, the procedure where several veterinary surgeons, software engineers and an industrial engineer lent their expertise, the surgery moved along expeditiously.

Researchers at Guelph University have performed what is believed to be the first major dog skull replacement using 3D-printing technology. (Canadian Press)

Two hours were taken to map out the plans, sending them to the printer, and the titanium skull cap was ready within two weeks. The surgery for Patches took four hours. And recovery was amazingly swift. Within a half-hour of coming out of the anaesthetic, Patches walked outside for a bathroom break, cancer-free.

There's more to Patches' story; she suffered a badly slipped disc in her back and hind legs a week after the surgery -- an incident unrelated to the surgery -- leaving her hind legs paralyzed. That hasn't stopped Patches, however. "She has a wheelchair that she refuses to use, so she pulls herself around on her two feet, but she’s pretty fast", said Ms. Dymeck. "I feel lucky to be her owner, and she’s still the boss of the house."