Blind gorilla sees again

Dissolving the damaged lens - under anaesthetic

By Alex Kirby BBC News Online environment correspondent

A western lowland gorilla born with cataracts in both eyes can now see clearly for the first time.

The gorilla, Romina, underwent a successful operation in Bristol, UK, to restore the sight of one eye. The team who operated on her hope to remove the cataract from her other eye.

The operation was the first of its kind in Europe on an adult gorilla. Romina, who is 21, came to Bristol Zoo Gardens (BZG) from Rome zoo in Italy, where she had been born and hand-reared.

Checks by the staff at Bristol revealed the cataracts, which had left Romina with only minimal peripheral vision.

Taking no chances

The operation, on 12 March, took place in the veterinary department of Bristol University.

A medical ophthalmologist, Jenny Watts, performed the surgery, assisted by a veterinary ophthalmologist, David Gould, and other veterinary staff.

Before the operation

Most human cataract patients remain conscious during surgery, but Romina, who weighs 120 kg (260 pounds), was anaesthetised.

The only previous comparable operations are two on juvenile gorillas at Rotterdam zoo in the Netherlands, and two on adults in the US, in Utah and Ohio.

The Bristol team lacked basic information, such as the exact structure of a gorilla's eye, and most of the operation was taken up by detailed ultrasound measurements of Romina's eye to calculate the strength of the artificial lens she needed.

Both her eyeballs were found to be much longer from front to back than the team had expected - she was very short-sighted.

The cataract was then broken up by ultrasound for removal before the foldable silicon lens was inserted - exactly the same procedure as used in human patients.

Instant success

Before the operation, Romina had learnt to maximise what vision she had by shading her eyes with her hand to cause the pupils to dilate, allowing her to see some shapes in dim light.

Sharon Redrobe, head of veterinary services at BZG, said: "As soon as Romina came round from the operation we could tell that she could see.

"She immediately reached towards food without resorting to feeling her way. We're delighted that the operation has been so successful and that she is having the chance to explore her surroundings and companions properly for the first time."

But post-operative care, with the risk of infection, was a tricky business.

Under the microscope

Melanie Gage, in charge of primates at the zoo, said: "We had to encourage Romina to come as close as possible to the keeping team so that we could safely give her antibiotic eye drops four times a day both before and following the operation.

"In the end, we devised a system of drizzling the solution through a catheter, so that the drops ran gently into her eye."

Future prospects

The director of BZG, Dr Jo Gipps, said: "It used to be thought that lowland gorillas were significantly more plentiful than their highly threatened cousins, mountain gorillas.

"Now forest destruction for logging and the effect of the illegal bushmeat trade means that lowland gorillas face serious losses in the wild population."

Dr Gipps said he hoped Romina and the zoo's other gorillas, Bongo and Salome, would soon start breeding.

Images courtesy of Martin Chainey/Bristol Zoo Gardens