Sheryl Wolfe, recently crowned Miss Hawaii Teen United States, died in Hawaii from a stroke Tuesday at the age of 18. The teenager, who had no health problems and no family history of stroke, had collapsed while sitting in class at her high school, and was in a coma for a week. Christopher Loftus, professor and chairman of neurosurgery at Temple University School of Medicine and Hospital, says most aneurysms and AVMs come on with little warning. "And if that is what she had, 50 percent of people die on the spot," he explains. "About half of those who survive come out okay, and the other half have disabilities. So, it's a pretty bad thing to have happen to you."