Doctors have given the go-ahead to experimental brain surgery which could save a five-year-old girl's life.

Without the treatment Sacha Skinner, who suffers from the rare disorder Batten Disease, is not expected to live beyond the age of 12.

The disease, which affects the nervous system, has left Sacha unable to say more than three or four words and her mobility is deteriorating.

The operation could enable her to live a normal life or stop the condition worsening.

Yesterday Sacha and her parents Annette Dacosta and Neil Skinner returned from New York's Cornell University, where the treatment is being pioneered, after three days of tests to check she is fit enough to undergo the intensive operation.

Sacha is expected to return to the US in May providing she does not have any seizures for the next three months.

Ms Dacosta, 37, of Firle Road, Brighton, said: "I am very nervous and very apprehensive about the treatment.

I need to speak to other parents before we go so I am 100 per cent sure this is the right thing to do for Sacha but I want to give her every opportunity possible.

"Being in New York was quite upsetting at times. Sacha had so many tests and at points we had to hold her down while she was crying. We know it's for the best so we just have to get on with it.

"Sacha was in wonder at New York. We went to Central Park and took her to the zoo to see the polar bears and penguins. We went to Times Square and on Sunday morning we had a good walk together down Fifth Avenue before she was admitted to hospital."

Only two children in the UK have had the treatment which involves drilling six holes in the head and inserting a harmless virus carrying replacement genes. One of the two children died but the parents of the other say her condition has stabilised.

Sacha's parents have been fighting for the treatment since their daughter was diagnosed with Batten Disease last July. A long wait while her DNA was analysed in Holland followed and doctors discovered she had a strain of the disease never seen before.

In New York, doctors took notes on her condition for future research. Sacha had a two-hour MRI scan, blood tests, HIV tests, sight tests and had her heart monitored.

Property developer Chris Weatherstone, from Hove, paid for the trip after he read about Sacha's plight in The Argus.

Ms Dacosta said: "The doctors have been very open with us and are not promising any miracles."