Misani, a 12-year-old western lowland gorilla living at the San Diego Zoo Safari Park, regained her health through a surgery that marked a first in medical history. Misani underwent the world's first recorded mastoidectomy to treat an infection that had spread to her skull bone.
The operation was carried out by a large team of surgeons from UC San Diego Health Medical Center and wildlife health specialists from the San Diego Zoo Safari Park.
Symptoms and Diagnosis
In March 2026, caretakers noticed that Misani was having difficulty opening her mouth, had a decreased appetite, and was exhibiting behaviors indicating a headache. A CT scan at the park's Harter Veterinary Medical Center diagnosed sinusitis and mastoiditis (inflammation of the large bone behind the ear). It is thought that the illness may have begun before Misani arrived at the Safari Park in November 2024.
Historic Surgery
The key figures in the surgery were Dr. Jeffrey Harris, an ear, nose, and throat and head-and-neck surgeon from UC San Diego Health, and resident physician Dr. Krish Suresh. Thanks to the similarities between human and gorilla anatomy, the team adapted methods from human medicine. However, because there was no previous record of a mastoidectomy on a gorilla in the scientific literature, the operation required extremely meticulous preparation.
Dr. Harris said, "Our team regularly performs mastoid and skull base surgeries, but applying this knowledge to a critically ill gorilla required extremely meticulous preparation."
During the surgery, an incision was made on the left side of Misani's head to reach the infection site. After the infected mastoid bone and tissues were removed, the wound was carefully closed. More than 20 specialists, including veterinarians, doctors, licensed veterinary technicians, animal caretakers, and support staff, participated in the operation, which lasted a total of five hours.
Safari Park Senior Veterinarian Dr. Ryan Sadler said, "This case is unique because such a disease is extremely rare in gorillas, and it was a significant professional experience for all of us."
Rapid Recovery
After the surgery, Misani recovered quickly. A follow-up examination in early June showed significant improvement and no complications. Experts stated that the operation successfully eliminated the problem. If no new symptoms appear, the next check-up is planned for one year later.
Misani has already returned to her group, is eating normally, is active, and continues her usual lifestyle.
The Harter Veterinary Medical Center, which celebrates its 25th anniversary this year, has provided care for more than 50,000 animals from hundreds of species since its opening in 2001. The San Diego Zoo Wildlife Alliance, through global collaborations, has contributed to the return of more than 44 endangered species to their natural habitats.
