When Leonie Clarke went to hospital with a neck problem she thought, worst case scenario, she might need a neck brace. It turned out she needed brain surgery.

"I came out bawling my eyes out," Ms Clarke said.

At 53, Ms Clarke was diagnosed with Chiari malformation — a rare brain disorder that affects about one in 1,000 people.

"I kept googling it because I couldn't remember the name to tell everybody," she said.

Chiari malformation is when the back of the brain is pushed out of the skull and onto the spine blocking the flow of fluid.

It had caused Ms Clarke to start fainting 30–40 times a day.

Following painful surgery to relieve some of her symptoms Ms Clarke, at the age of 55, decided to finally follow her dreams and try stand-up comedy.

"There happened to be a stand-up comedy workshop next door, in the hall next door to me," she said.

"The guy [running the workshop], who is now my producer, thought I'd accidently walked into the wrong place because I looked a lot older than the others there," she said.

After six months of training, she was writing her own material and performing in front of live audiences.

Later this month the grandmother will compete in the WA semi-finals of the Raw Comedy competition.

Leonie Clarke hands out this Chiari WA flyer during her stand-up shows. ( ABC South West: Kate Stephens )

Despite the pain and constant fainting, Ms Clarke has found the funny side of her disorder and uses her stand-up shows to make jokes and raise awareness of Chiari formation.

"I can always see the funny side in anything," she said.

Comedy and Chiari

Laughing about what she described as her "brain falling out of her head" was not enough for Ms Clarke, so she decided to start a local support group, Chiari WA.

The group currently has 87 members and uses social media to connect people across WA who suffer from the rare disorder.

It is how she met mother-of-two Katherine Kay, who was diagnosed with Chiari in 2016 at the age of 23.

Katherine Kay says her diagnosis has taken a big financial toll on her family. ( Supplied: Katherine Kay )

"It's been the biggest rollercoaster of my life, because I ended up having to go to Sydney for my surgeries," Ms Kay said.

She was forced to leave her children at home for two weeks to fly from Geraldton, in Mid West WA, to Sydney to have part of her skull and C1 vertebrae removed.

"It's been the biggest financial burden on us as well because the surgeon who we saw in Sydney was private and then of course there's flights, accommodation, all the costs that go with being over there for two weeks," Ms Kay said.

She said having a group in Western Australia to speak to about her diagnosis and ongoing treatment had helped her get through the tough days.

"I can just get on there and have a little bit of a vent if you are having a bad day and people actually understand what you are on about."

Patients can be 'fobbed off' for years

Katherine Kay was left with this huge scar on the back of her head after her surgery. ( Supplied: Andrew Holberton )

Marcus Stoodley is a Professor of Neurosurgery at Macquarie University and said while it was not clear what caused the disorder, genetics could play a role.

"Probably about 10 per cent of the patients have a family history of Chiari malformation, so there's clearly some sort of genetic transmission, although the majority of patients have no family history of it," he said.

Professor Stoodley believed because the disorder was so rare, despite experiencing severe pain, some patients can go from doctor to doctor without a proper diagnosis.

"Patients feel like their symptoms have been dismissed or fobbed off or underrated by doctors they've seen," he said.

"By the time I've seen them they can be a little bit cynical about the whole thing."

But Leonie Clarke is not cynical at all, rather seeing the funny side to the whole experience.

"I mean if I hadn't got Chiari, I wouldn't be doing this and I'm loving it," she said.

"I've had the best five years of my life really."

Editor's Note (19/2/19): This story has been amended to clarify that about one in 1,000 people are affected by Chiari malformation, not one in 10,000, as originally reported.