This month's death of a Butler University pharmacy professor was caused by a stroke precipitated by a fall she took while snowboarding in Colorado, the Summit County coroner's office said Friday.Jennifer Ash, 28, of Indianapolis, was snowboarding at Keystone Ski Resort when she fell "quite hard on her buttocks" March 16, the coroner's office said. Her friends took her to a medical center and doctors eventually determined she had suffered a vertebral artery dissection -- or a tear in a vertebral artery -- the coroner's office said.The dissection led to a stroke and brain damage. She was declared dead days later, the coroner's office said."This type of injury occurs with an indirect trauma where there is a whipping motion of the neck," the office said in a news release.Keystone spokeswoman Kate Lessman told Denver ABC affiliate KMGH that the resort wasn't told of the injury on the mountain and didn't know about Ash's injury until Friday, when coroner's office released its report."Usually, when there's an incident on the mountain, the people in the party will call the ski patrol. The ski patrol was not contacted in this case," Lessman said.The coroner's office also said no one had told ski patrol about Ash's fall. The office said no one with Ash assumed the fall to be serious at the time.Ash was in her first academic year on faculty at Butler's College of Pharmacy and Health Sciences, according to Butler spokeswoman Courtney Tuell.She received her doctorate in pharmacy from Butler in 2003, Tuell said.Ash had arrived in Colorado with friends on March 15 for a vacation, the coroner's office said.