A gorilla enjoys the treats in a giant advent calendar during an 'Animal Adventures this Christmas' photocall at Zoological Society of London (ZSL) London Zoo, in London, Britain, on Dec. 20, 2018. Zookeepers of the ZSL London Zoo prepared some seasonal surprises for the Zoo's residents to enjoy on Thursday. (Xinhua/Isabel Infantes)

A team of eye doctors in California tested their skills on an unusual patient - a western lowland gorilla.

Working with veterinarians from the San Diego Zoo, an eye surgeon removed a cataract from the left eye of a three-year-old female named Leslie on December 10, zoo officials announced. They said the surgery was performed at the zoo's medical center and Leslie was recovering well.

The surgeon who performed the procedure, Chris Heichel, said that while he had carried out thousands of eye surgeries on human patients, this was his first on a gorilla. "Fortunately, the similarities between the anatomy of human and gorilla eyes are great enough to allow us to safely navigate the procedure," he said.