Christy's parents were at their wits' end. About two months before, she had been fine, walking and talking like any 2-year-old. Then she got a cold. First her eyes started jiggling; then her body began jerking. The twitches were so strong she couldn't talk or walk. She fell often, was covered with bruises, and had trouble sleeping. Her parents had taken her to a pediatrician, who referred them to a neurologist. He said Christy was still fighting a virus and would get better. When she didn't, her parents brought her to me for another opinion.
My physical examination included tests of balance and coordination. From Christy's responses I could see she had suffered an injury to her cerebellum, a fist-sized structure at the base of the brain that helps execute movements. But I also knew that her jerks and eye movements had to originate in the brain stem, a slender stalk of tissue that connects the brain to the spinal cord. Her problems with language and behavior probably meant other brain structures were involved too. I told the parents that Christy had OMS--opsoclonus-myoclonus syndrome. The name is simply a description of the symptoms. Opsoclonus refers to the jiggling eye movements, and myoclonus is a term for the muscle jerks.
OMS is caused by a brain injury, but the problem can't be easily detected on brain scans. The brain contains a staggering thousand trillion junctions between neurons. It would take a malfunction in only a small percentage of neurons to produce Christy's symptoms. "Can this be cured?" her mother asked. I shook my head. "I'm talking about treatment, not cures."
