Alyssa Ledbetter suffered brain damage while holidaying in America last month.

A Bay of Plenty girl who spent weeks in intensive care in an American hospital has been discharged and hopes to be home in two weeks.

Alyssa Ledbetter was in Seattle at a family reunion with her brother, Rayna, father Dave - who is from America - and mother Tarnya, from Hamilton, when she suffered a brain bleed.

The 11-year-old Whakatāne student was swimming in Lake Washington on July 21 when she emerged from the water complaining of a headache, neck pain, blurry vision and numbness in her legs.

At first, Dave thought his daughter had suffered a spinal injury of some sort.

They helped Alyssa to the lifeguard tower but her condition quickly deteriorated.

She lost control of her bodily functions and began to seize uncontrollably, says Dave.

Alyssa's blurred vision worsened and she couldn't recognise the people in the room. She then fell in and out of consciousness.

A neurosurgeon happened to be picnicking nearby and came to Alyssa's aide.

'The quick-thinking doctor sent Alyssa to Harborview Medical Centre, the primary trauma hospital for the states of Washington, Alaska, Montana and Idaho,” says Dave.

He believes if this did not happen, Alyssa would have suffered permanent and irreversible brain damage.

"[The doctor] acted straight away and called ahead to her hospital.”

"When we arrived, there were eight specialists there waiting.”

"She's a guardian angel and a personal friend with us now."

Surgeons drilled through Alyssa's skull to drain the fluid and relieve pressure.

They were told Alyssa had two arteriovenous malformations in the frontal cortex of her brain.

Alyssa suffered a subarachnoid haemorrhage when the weakened blood vessels in her brain burst from the high pressure of blood flow from the arteries, causing bleeding into the brain, says Dave.

"The neurological doctors have determined that open brain surgery is not an option, as the AVM is too deep inside her brain and the risk of permanent damage is too great - the only other realistic option is gamma knife radiosurgery."​

The cause of AVMs is not clear, according to information on the American Heart and Stroke Association website.

Most people are born with them, but they can occasionally form later in life. They are rarely passed down among families genetically.

Some people with brain AVMs experience signs and symptoms, such as headache or seizures. AVMs are commonly found after a brain scan for another health issue or after the blood vessels rupture and cause bleeding in the brain, as in Alyssa's case.

Once diagnosed, a brain AVM can often be treated successfully to prevent complications, such as brain damage or stroke.

After spending more than two weeks in hospital, Alyssa was discharged, but returned a day later with the same symptoms she suffered when she was first admitted, though to a lesser extent.

"It's a long journey and symptoms will continue to show at times. She has to ease back into her normal life. She gets tired and overstimulated easily now."

Dave said Alyssa will have to complete outpatient treatment before she is cleared to fly to New Zealand.​

Once in New Zealand, Alyssa will have to wait at least three to six months for her brain to heal sufficiently before she can undergo gamma knife surgery.

"Unfortunately, there is no gamma knife surgery available in New Zealand. The closest is in Sydney, Australia. One or more trips to Sydney may be necessary."

Dave says the family won't know the cost of the surgery until they have a consultation with a neurosurgeon in New Zealand.

And even with the surgery, it can take three years to see results.

Dave says his daughter has always been a healthy and active child who loves hip-hop dancing and various sports, including field hockey, swimming and surf-lifesaving.

Dave volunteers as a lifeguard.

The family have been overwhelmed with the support they've already received and want to say thank you to all who have supported them, either with well wishes or by donating to their crowdfunding campaign.

The costs while in America have been covered by their insurance company, but the family are raising funds for ongoing medical expenses - including the gamma knife surgery - ongoing CT and MRI scans, medications and various travel and accommodation expenses.

"It has humbled us and made us really appreciative."

-Stuff.