Cataracts are a common eye condition marked by a cloudy lens that can be extracted fairly easily. For humans, anyway. But on June 12th, the patient on the operating table wasn’t a person—it was a lion.
Experts diagnosed an African lion (Panthera leo) named Tsavo with cataracts over half a year ago. He was rescued as a cub in 2013 and currently lives at Wildlife Safari, a wildlife park and conservation center in Oregon. Last week, his veterinarian team successfully carried out the eye operation. It should improve the lion’s quality of life significantly and represents an international effort, with experts using equipment from around the world.
The surgical process started at around 2 p.m., and less than three hours later the team had removed the two cataracts and replaced them with custom-made artificial lenses. At 5:15 p.m. Tsavo was back in the Lion Hut, where he started his recovery under the watchful eye of the wildlife park’s carnivore team.
“One of the most surprising things is that the surgery itself is almost identical to modern human cataract surgery,” Cassandra Bliss, a veterinary ophthalmologist at Bliss Animal Eye Care who co-led the entire team, tells Popular Science. “The biggest differences are the anatomy and the patient. A lion’s eye is significantly larger than a human eye, requiring specialized calculations and a much larger artificial lens.”
The successful operation was the result of months-long preparation and coordination among veterinary professionals and medical technology experts from across the planet. Tsavo now has clear visual pathways again, and he is also expected to regain his binocular vision and depth perception.
“Vision is one of the primary ways lions interact with their environment,” Bliss explains. “Restoring sight isn’t just about seeing again, it’s about allowing an animal to navigate its world, engage with enrichment, recognize familiar caretakers and companions, and express the natural behaviors that contribute to its quality of life.”
Benjamin Alcantar, Head Veterinarian at Wildlife Safari was the other co-lead. He and Bliss had previously carried out cataract surgeries on two Wildlife Safari lions last year.
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