(NEW YORK) -- One day, 6-year-old Keira Vidikan developed a minor headache just before heading off to her ballet class in Dayton, Ohio. Less than two weeks later, she was in a coma at the Cleveland Clinic, nearly paralyzed and unable to speak.
"I think this was the darkest night we will ever have," said her mother, Michelle Vidikan.
After scanning Keira's brain, emergency room doctors suspected a glioma, an aggressive form of brain cancer. As Michelle and her husband, Mario, waited out the night at the local hospital, their daughter was slowly dying.
But in the morning, after six hours of tests, there was a ray of hope. An MRI showed the mass was more vascular in nature, and Keira was referred to the Cleveland Clinic for an evaluation.
Keira was diagnosed with cavernoma, a rare form of a family of conditions known as arteriovenous malformations or AVMs. A cluster of extra blood vessels had formed on her brain stem and had hemorrhaged. It was not cancer.
In December, Keira was a breath away from death, but today, she has returned to school thanks to prompt attention from her parents, optometrists and surgeons at Cleveland Clinic.
About 300,000 Americans suffer from AVMs, which are defects of the circulatory system that are generally believed to arise during embryonic or fetal development or soon after birth, according to the Cleveland Clinic. Although they can develop anywhere in the body, those in the brain or spinal cord can have devastating effects on the body.
"She was pretty bad off," said her neurosurgeon, Dr. Peter Rasmussen, director of Cleveland Clinic's Cerebrovascular Center.
"No one really understands these cavernomas very well," he said. "A lot of them grow and stabilize at a small size. She also had an unusual subset that was progressively enlarging over time. She was four or five weeks into this, and hers was just growing and growing like an aggressive tumor."
Keira's condition only occurs at a rate of about 1 in 500,000 in the general population, according to Rasmussen.
"It's a lot more common in women in their early 40s," Rasmussen said. "It's relatively rare in children."
Usually, the patient is treated with steroids and observation, but Keira was "clearly deteriorating," he said.
The greatest danger, as in Keira's case, is bleeding, which happens only in about 2 to 4 percent of all AVMs. Without prompt treatment, she could have also suffered a stroke, according to Rasmussen.
Surgery is the only treatment, but that, too, can be risky.
"The brain stem sits right smack dab in the middle of your head, and you've got to get into that area," he said. "The brain stem is sort of like an octopus with arms and nerves that provide movement to the face, eyes, mouth and lips, so you have to be able to work in between the nerves to get in to the substance of the brain itself and move it and pull it out of there."
"She's absolutely a real fire plug and clearly the darling of her parents," said Rasmussen, who was happily surprised with Keira's quick bounce-back. "She's an absolute gem."
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