SUMMIT COUNTY (MyFOXColorado.com) - A 28-year-old snowboarder has died after suffering a severe brain injury from –what appeared to be- an innocuous fall at Keystone.

Jennifer Ash, from Indianapolis, Ind., fell hard on her buttocks while snowboarding on the Ina’s Way run late in the afternoon on March 16, the Summit County Coroner said.

Ski Patrol was not notified because the accident was not assumed to be serious.

Ash’s friends drove her to Summit Medical Center where she was evaluated and sent by critical care to St. Anthony’s Central Hospital in Denver where it was discovered that she had suffered vertebral artery dissection, the coroner said.

The injury resulted in a basilar artery stroke and brain damage attributed to the fall.

Ash was pronounced brain dead on March 23.

The coroner said this type of injury occurs with indirect trauma where there is a whipping motion of the next that can be hyperextension of side-to-side.

While Ash was not wearing a helmet at the time of the fall, it would not have prevented the injury, the coroner said.

Ash, a pharmacist, had arrived in Colorado on March 15 with friends for vacation.