While her friends concentrated on picking deb outfits and university preferences, Rachel was rolling the dice on a world-first surgery that could have taken her memory or left her paralysed.

"I was diagnosed with epilepsy when I was 15, just out of nowhere," the 19-year-old Illowa resident said.

"At night I was having three or more seizures a week.

"They didn't know what was wrong.

"One doctor said I was taking drugs."

For three years Rachel took medication, trying to control her seizures without success.

As a result, she couldn't learn to drive and she couldn't go out with friends. The typical teenage experience of a weekend sleepover became a mere fantasy.

It was almost two years before she was comfortable with even sharing information on her condition with friends.

"It was hard to tell them because I didn't want to be treated differently," she said.

"Even though people say they won't, they do."

Her rare form of epilepsy, known as Bottom of Sulcus Dysplasia, was compared to a birthmark on the left side of her brain, which controls speech and memory.

The tiny lesion was so indistinct it could only be found using the latest in imaging technology.

After transferring from the Royal Children's Hospital to Melbourne's Austin Hospital, Rachel met consultant neurologist professor Graham Jackson, who told her about a new neurosurgery option.

By forcing her body into focal seizures, new thermal imaging technology would help surgeons perform a more precise operation than was previously possible.

The upside was her epilepsy was potentially curable, with a 70 per cent chance of dramatically improving her condition.

On the other hand, the surgery had never been done anywhere in the world. She would be the first to even try it.

While highlighting the benefits, doctors warned Rachel would have a small chance of suffering a stroke on the operating table.

"There was also the risk of paralysing the right side of my body and speech and memory loss," she said.

"The risks put us off for awhile, but I was still thinking about it."

Over several years, Rachel's parents Frank and Carrol had watched epilepsy turn their typical teenage daughter into a young woman struggling to get through her increasingly chaotic life.

Carrol was against the risky operation at first. There was too much to lose.

But deep down she knew she wanted a better life for her daughter.

"Her friends were wondering why she was missing so much school," she said.

"Having more seizures during the night, the next day she was knocked out and she couldn't get up.

"How do you tell a teenager you're not supposed to stay up late or go to a nightclub and see all those flashing lights?"

Finally, Rachel couldn't take it anymore. She decided to take a leap of faith and place her future in the highly-trained hands of the Austin Hospital surgeons.

"I didn't want to go through life being like 'what could have happened?'

"I felt like I couldn't do anything.

"I wanted to help myself because I felt just going through my life like that was going nowhere.

"I went in there with no expectations, so if I came out with exactly the same as before I wouldn't have been upset.

"It was exciting. Even though there were risks, I wanted to take the chance."

While Rachel was fuelled by the hope of a better life, her supportive parents were wary of the consequences.

Carrol said the day of her daughter's procedure last May was the longest of her life.

"I thought of every possible thing that could go wrong, but she was just positive," she said.

"When they called me afterwards I burst into tears.

"They said 'she's woken up' and she could speak."

Just days before the procedure, PhD student Mangor Pederson was looking through Rachel's MRI scan and discovered a previously unseen detail that pinpointed the precise area of epilepsy.

The surgery, performed by professor Gavin Fabinyi and professor Sam Berkovic, successfully removed part of her brain, comparable in size to the tip of a ballpoint pen.

Carrol said her daughter had enjoyed an everyday lifestyle ever since - finishing school, learning to drive and now studying the second year of a Bachelor of Education at Deakin University in Warrnambool.

"She's just grown into a beautiful woman," she said.

"She's starting to live a normal life, which people take for granted."

Doctors said they wouldn't know for sure if the operation was successful for two full years, but it's hard to argue with the results.

Rachel's undeniable joy as she speaks about her new life says it all.

"I haven't had any seizures, nothing," she said.

"I feel like a different person. More positive.

"I can see the future now.

"I can do stuff now with my friends and not worry, and I don't have to check in with my parents."

Rachel's improved condition has the Florey Institute of Neuroscience and Mental Health calling the procedure a "game-changer".

Professor Jackson, who is also Melbourne's Brain Research Institute director, described Rachel as "a special case" and said her brain was now functioning as it should.

"Patients all become your own children in a way. You become very proud of them," he said.

"Rachel changed after her surgery.

"It's delightful to see the young lady she is now.

"It's a fantastic privilege to get involved in people's lives like that.

"She's influenced our thinking and other surgical candidates' thinking.

"It's a proof of principal in an extraordinary way, that such a tiny part of brain can cause such mischief.

"We're trying to communicate that to the world now."

Professor Jackson said the rest of the world was yet to adopt the Florey Institute's new imaging technique, but the industry was now paying attention.

"We have applied that technology to quite a few patients now," he said.

"This morning we found two more people who could be treated like this and we wouldn't have found that three or four years ago.

"It's our ambition to do that for everyone. The key to it all is to have a vibrant research community.

"Rachel years ago wouldn't have had surgery or would've had a larger resection that could've had brain damage as a result.

"We live with lots of patients who I know should've had this surgery, but they're in their 40s and 50s with greater risks.

"We know if only we could've helped them their lives would be different."

While Rachel's dream of living a normal life has become a reality, she now wants others living with epilepsy to know they are not alone.

"Apparently there's been a lot more people going into the hospital to see if they can have surgery," she said.

"It's not rare for people to get diagnosed in their teens or early 20s.

"These people might think that there's nothing that can be done, but there is.

"I just want to spread the word so people know they're not alone.

"Take a risk but you have to know in your heart. You have to really be strong to think that it's going to work out.

"You just get that feeling if something is right."