Autopsy: Natasha Richardson died from hitting head

This image made from video shows Liam Neeson, left, leaving Lenox Hill hospital in the back seat of a car in New York on Wednesday March 18, 2009 shortly after the announcement that his wife actress Natasha Richardson died. Richardson, 45, died Wednesday after suffering a head injury in Canada on Monday during a beginners' ski lesson. Sitting next to Neeson is Richardson's sister, actress Joely Richardson. (AP Photo/APTN)