FILE - In this March 12, 2010 file photo Mercedes Grand Prix driver Michael Schumacher of Germany is pictured in the garage after finishing the second practice session at the Formula One Bahrain International Circuit in Sakhir, Bahrain. Schumacher is being treated at a hospital in Grenoble after sustaining a head injury during a ski accident in Meribel, France. Doctors treating Michael Schumacher refused Monday, Dec. 30, 2013 to predict the outcome for the former Formula One driver, saying they were taking his very critical head injury "hour by hour" following his ski accident. Chief anesthesiologist Jean-Francois Payen told reporters that the seven-time champion is still in a medically induced coma. (AP Photo/Ben Curtis, File)GRENOBLE, France (AP) — Michael Schumacher underwent a 2d surgical operation after a brain scan confirmed small, “stunning” indicators of growth, but grim docs mentioned Tuesday they could provide no insight into the prognosis for the Formula One champion.