The family of a Fremantle man critically injured in a motorbike crash in Thailand have been delivered more devastating news.

Ben French has developed a brain infection which will make it difficult recover from, his family told 7 News.

He was flown to Royal Perth Hospital's intensive care unit on Friday night in an emergency medical flight thanks to the $100,000 donated to the family by strangers though an online crowdfunding page and a local fundraising event.

View photos A Medivac plane transported the scooter-crash victim from Thailand to the Royal Perth Hospital. Source: 7 News More

His mother was by his side for the seven-hour flight.

Last week the 34-year-old Fremantale man was on the holiday island of Koh Samui when he came off his scooter on a bend and suffered horrific injuries.

View photos This picture, taken in Thailand, shows the extent of Ben French's injuries. Source: 7 News More

View photos He had earlier shown small signs of improvement. Source: 7 News More

Ben French is in a coma, with his back and ribs broken, and both lungs punctured.

Doctors took off the top of his skull to deal with his shocking brain trauma.

View photos Known Perth foodie Ben French, critically injured in a motorbike crash, has developed a brain infection. Source: eatnoevil1/Instagram More

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