(CNN) -- Johan Friso, the 43-year-old Dutch prince who was injured in an avalanche at an Austrian ski resort last week, has suffered brain damage, his doctor said Friday. 

"After the latest neurological test we conducted yesterday it became clear that the lack of oxygen (to) the brain of the patient caused massive damage," Dr. Wolfgang Koller told CNN affiliate SBS NL. 

"Fifty minutes of reanimation is a very long time. One could also say too long," he added. "Our hope was that the relatively moderate level of hypothermia might have protected the brain somewhat. Unfortunately this was not the case." 

Friso, a son of Queen Beatrix of the Netherlands, had been airlifted to hospital in Innsbruck after the incident. 

He was skiing outside the bounds of the ski resort with friends at the resort of Lech am Arlberg when he was hit by an avalanche, a spokesman for the state of Vorarlberg said. 

No one else in the group was injured. 

The prince was under the snow for a "short period of time," the spokesman said. He was wearing an electronic beacon that helped rescuers quickly find him. 

Lech am Arlberg is in Austria's Vorarlberg state, a popular skiing area in western Austria. 

The town's mayor told the station "that we have hoped for a miracle." 

"We have hoped that Prince Friso will recover again," said Mayor Ludwig Muxel. "There had been similar accidents and people nearly recovered fully. So we hoped that his health conditions would improve." 

The region's avalanche agency reported there was a considerable to great chance of avalanches in Lech last week. It cited new snowfall on top of a packed layer of snow that could cause snow slabs to slide off. 
At the time of the avalanche, where in the ski resort?
He was skiing outside the bounds of the ski resort