You've probably already heard that Daijiro Katoh lost his battle for life after craching his motorbike in the first race of the season I know that motor cycle racing is a dangerous occupation. Katoh knew that too. But with safety being high on the agenda when designing race tracks, motor sport deaths are very few and far between. He was only 26 years old and a rider with a big chance of going places. The official cause of death was "brainstem infarction". What exactly is that?