A bird with cancer living at ZooTampa has a second life thanks to its carers, specialists from the University of South Florida and Tampa General Hospital, surgeons from the University of Florida and technology from 3D printing.
Crescent is a 25-year-old, one-meter-long large hornbill, native to Nepal, Bhutan, India, Southeast Asia and Sumatra. The numbers are decreasing; the International Union for Conservation of Nature classifies the great Indian hornbills as “vulnerable”. When Crescent’s caregivers at ZooTampa noticed a peculiar lesion at the base of his helmet (the helmet-like growth on a hornbill’s upper beak), they feared it was squamous cell carcinoma. .
ZooTampa vets confirmed the lesion was a large cancerous tumor, a common skin cancer in humans, usually fatal in hornbills. Zoo veterinarian Dr. Kendra Baker immediately sprang into action and began calling in several experts to help save Crescent’s life.
“Everyone was absolutely critical,” she said. “Even though they weren’t present for the surgery itself, the planning and preparation for this procedure was so important.”
The innovative surgery was the first of its kind on a hornbill in the United States and only the second attempt in the world. Baker explained that the problem with this type of cancer is that it is locally very aggressive and would likely have eaten through Crescent’s helmet and beak. This makes it virtually impossible to eat, making the diagnosis usually fatal.
ZooTampa enlisted experts in radiology and clinical 3D printing applications from the Department of Radiology at the University of South Florida’s Morsani College of Medicine, who also work with Tower Radiology at Tampa General Hospital, to help replicate a procedure attempted only once in Singapore.
“We’ve built on that, used our own connections here, and it seems to be working out pretty well for her,” Baker said. “It’s really exciting that we’re essentially getting ahead of this condition in the species because historically it hasn’t gone well.”
Unlike most helmet tumors typically found in hornbills, Crescent’s cancer was near the back of its beak, near its skull. This made removing the tumor – vital to Crescent’s survival rate – more problematic as it would expose his sinuses. So veterinarians at ZooTampa and the USF 3D Clinical Applications Department began designing and printing a new custom 3D helmet for the hornbill. They also created a 3D-printed surgical guide to ensure surgeons remove the cancer in its entirety.
“We’ve made it as easy as possible for surgeons to work,” Baker said. “They were basically given a stencil to know where to cut…”
ZooTampa vets and two University of Florida vets carefully excised the irregularly shaped tumor before attaching the 3D-printed helmet to Crescent’s beak with acrylic and titanium dental screws. The prosthesis covers his sinuses, and Baker said Crescent immediately regained full use of his beak.
Baker explained that although this area of a hornbill has blood vessels, there isn’t much tissue, which minimizes bleeding. She said the most surprising aspect was how quickly the team completed the operation.
“It’s just taking out the diseased part and putting this prosthesis in place,” she said. “The fact that the procedure was as quick as it was definitely surprised me.”
Crescent needed a lightweight but durable material for the prosthesis. Baker said something biocompatible that could absorb the hornbill’s natural pigments from its limpid gland was a bonus. These pigments provide the bright yellow coloration of Crescent’s beak.
The USF Health Radiology team reached out to their partners at Formlabs, a manufacturer of 3D printing solutions specializing in medical-grade materials. By chance, Formlabs was developing a new material called BioMed White Resin. This innovative compound met the performance requirements of the prosthesis and was also biocompatible.
“I’m not a materials expert — that’s not my expertise,” Baker said. “So to be able to pull all these experts from their own fields and talk to them about the end goal and then allow them to use their own experience was a really cool process.”
Formlabs donated the materials, and the USF Health team printed the surgical guide and new helmet on a Formlabs medical-grade 3D printer. The project will help create and place human prostheses, which Baker called a “giant leap” ahead of veterinary applications. She said similar human applications have access to more funding and that these procedures only involve one species.
Baker noted that there are now only two case studies for hornbills, four years apart. She said it could take another four years before vets try the procedure again.
Baker said Crescent was doing great after the surgery and recovered incredibly quickly. The hornbill returned to ZooTampa after just two days in the hospital. Baker said the bird’s eating habits and vocalizations are normal and her caregivers haven’t noticed any negative effects from the procedure.
“The fact that everyone has worked so well together and that we have reached out so well, I think it ultimately helps everyone to know that we all have our backs, and we are all here for the medicine and for make sure our patients get better,” she said. “It doesn’t matter whether or not it’s a bird or a human.”