First reported mastoidectomy performed on gorilla at San Diego park

A first-of-its-kind skull surgery at the San Diego Zoo Safari Park has put a spotlight on how far collaborative specialty care in zoological medicine has evolved. According to San Diego Zoo Wildlife Alliance, Mizani, a 12-year-old male western lowland gorilla, underwent the first reported mastoidectomy on a gorilla after an infection spread into the mastoid bone and portions of his skull. The operation was performed by wildlife health experts at the Safari Park alongside otolaryngology surgeons from UC San Diego Health. (sandiegozoowildlifealliance.org)

The case began after wildlife care specialists noticed changes in March 2026: Mizani was less willing to open his mouth fully, was eating less, and showed behaviors associated with head pain. A CT scan at the Safari Park’s Harter Veterinary Medical Center identified sinusitis and mastoiditis. The zoo said clinicians believe the disease likely predated Mizani’s arrival at the park in November 2024, underscoring how chronic head and skull disease in great apes can smolder before presenting with clearer clinical signs. (sandiegozoowildlifealliance.org)

What makes the case especially notable is the lack of prior published precedent. The San Diego team said its literature search found no prior record of this specific procedure in a gorilla, forcing surgeons to rely on human otologic and skull base experience while adjusting for species-specific anatomy. In human medicine, mastoidectomy is a standard but technically demanding temporal bone procedure used to access and remove infected mastoid air cells. Gorilla temporal bone anatomy shares enough overlap with humans to make adaptation possible, but published anatomical work also points to meaningful differences in mastoid morphology that can complicate direct translation of technique. (sandiegozoowildlifealliance.org)

San Diego’s announcement did not provide a full operative report, but it said the team made an incision along the left side of Mizani’s head, drained the infected area, removed portions of infected mastoid bone and tissue, and then closed the site carefully. UC San Diego otolaryngologist Jeffrey Harris said the team used CT review and “delicate microsurgery” to adapt its approach to the anatomical differences. That kind of planning mirrors prior human-veterinary collaborations in gorillas, including UC San Diego’s 2019 cataract surgery on Leslie, a 3-year-old gorilla at the same park, and a published 2018 report from Woodland Park Zoo describing endoscopic sinus surgery in a gorilla with severe chronic rhinosinusitis. (sandiegozoowildlifealliance.org)

The broader industry takeaway is less about novelty for novelty’s sake and more about capability. Zoo and wildlife veterinarians often manage species in which evidence is sparse, referral options are limited, and anesthesia time carries outsized risk. In the Woodland Park case, the surgical team described how even when human and gorilla anatomy are broadly similar, deeper structures, instrument reach, and intraoperative stability can change the entire procedure plan. That history helps explain why a mastoidectomy in a gorilla is newsworthy: it represents not only a technical milestone, but also a systems achievement involving imaging, anesthesia, surgical adaptation, and postoperative care in a species where every intervention must be carefully justified. (vet.k-state.edu)

Why it matters: For veterinary professionals, this case is a reminder that the frontier in exotic and wildlife medicine often lies in borrowing, then carefully modifying, tools from human specialty practice. The practical lesson is that referral relationships with academic medical centers can materially expand what’s treatable, especially in neurology-adjacent, skull base, ophthalmic, and ENT cases. It also reinforces the value of advanced imaging and multidisciplinary planning before anesthesia in great apes, where subtle behavioral changes may be the earliest clue to serious disease. (sandiegozoowildlifealliance.org)

There’s also a conservation and welfare angle. Western lowland gorillas are managed in accredited zoo populations with high individual value, so successful treatment of rare but severe conditions can have implications beyond a single patient. While this was a clinical intervention rather than a regulatory event or a peer-reviewed trial, first-reported procedures often shape future standards once teams share technique, complications, and follow-up outcomes in the literature or at professional meetings. That’s particularly relevant in primate medicine, where case-based knowledge still drives much of practice. (sandiegozoowildlifealliance.org)

What to watch: The next step is whether San Diego Zoo Wildlife Alliance and UC San Diego publish a detailed case report or conference presentation. That would clarify the surgical approach, anesthesia protocol, microbiology, postoperative management, and any species-specific modifications, giving zoo, wildlife, and exotic animal clinicians something more durable than a press announcement to build on. (sandiegozoowildlifealliance.org)