Black Rhinoceros Undergoes Portable CT Scan At Brookfield Zoo

BROOKFIELD, IL — On April 19, Layla, a 7½ -year-old, 2,300 pound eastern black rhinoceros who lives at Brookfield Zoo, underwent what is believed to be the first CT scan ever performed on this species. The zoo said the scan was necessary to help Chicago Zoological Society veterinarians determine the next steps for treating a known obstruction in Layla’s nasal passageway.

Layla was too large to move inside the zoo's animal hospital, where the zoo's CT scanner is located, so staff brought a CT scanner to Layla’s habitat instead, the zoo said. NeuroLogica, a subsidiary of Samsung Electronics, generously donated the use of its BodyTom®, the world’s first battery-powered, portable, 32-slice CT scanner, for the procedure. The process of moving Layla to and from the machine was extraordinarily delicate and required the presence and precision of a team of nearly 40 dedicated zoo staff, as well as technicians from NeuroLogica and Sound Technologies, who donated their services to set up and operate the CT machine.

“The CT scan provided diagnostic results that we could not have otherwise obtained,” Dr. Michael Adkesson, vice president of clinical medicine for CZS, which manages Brookfield Zoo, said in a release. “This procedure is an example of our commitment to providing the animals in our care with the most advanced medical treatment available. More importantly, though, the CT scan on Layla has provided us an unparalleled look inside of her skull. The images we obtained will guide our future treatment plan. We are extremely grateful to NeuroLogica and Sound Technologies for their support in this critical undertaking to help Layla.”

The zoo said Layla began experiencing difficulty breathing in December 2017 and was diagnosed with obstructive sinusitis. Rhinos are obligate nasal breathers, meaning it is difficult for them to breathe comfortably through their mouth for long periods. Any sort of nasal obstruction can become dangerous, and after failing to respond to standard medical treatments, Layla underwent bilateral sinusotomy surgery at the zoo on Jan. 29. Veterinarians were able to identify a bacterial infection in her nasal passageway.

According to the zoo, this surgery significantly improved Layla’s comfort levels and allowed staff to begin treating her infection. Over the past two months, Layla has been anesthetized on a weekly basis for intravenous antibiotic therapy and to continue debulking, or removing, infected tissue through two surgical holes created to access her sinuses.

However, despite her progress, the initial surgery was unable to identify the source or extent of the problem, and advanced imaging was needed to complete treatment. The zoo said the images obtained on the CT scan have revealed abnormal tissue associated with the root of one of Layla’s upper molars. The growth of this tissue is causing the obstruction in her nasal passages and sinuses.

To prepare for the CT scan procedure, the Chicago Zoological Society’s carpenters constructed a custom-made platform. The zoo said after being anesthetized and stabilized, Layla was carefully slid onto the platform and a front-end loader was used to gently move her onto the zoo's large surgical table. Animal care specialists and grounds staff then carefully moved the table to the portable CT scanner set up in the Pachyderm House. The procedure was possible, in part, due to several practice runs staff had performed using 2,300 pounds of concrete to simulate Layla's weight.

The zoo said Layla currently is comfortable in an area behind the scenes, while veterinarians are developing a plan to surgically remove the remaining abnormal tissue and to provide subsequent treatment for Layla.

“Not only is Layla valuable to the rhinoceros population in professional care, she also plays an important role at Brookfield Zoo by raising awareness about the species and why conservation efforts are so critical,” Amy Roberts, senior curator of mammals for CZS, said in a release. “When our guests come to see Layla and our other black rhinos, we hope they will be inspired to care about these amazing animals so that future generations will be able to also appreciate them.

According to the International Rhino Foundation, in the 20th century, the black rhinoceros suffered the most drastic decline in total numbers of all rhino species. Between 1970 and 1992, the population of this species decreased by 96 percent. In 1970, it was estimated that there were approximately 65,000 black rhinos in Africa, but less than 25 years later, there were only 2,300 surviving in the wild. The black rhino population is recovering and increasing very slowly, but poaching remains a great threat.

Photos provided by Chicago Zoological Society.