Michael Schumacher Michael Schumacher

Michael Schumacher underwent a second surgery after a brain scan showed small, "surprising" signs of improvement, People reports.

However, doctors said Tuesday that they couldn't offer any insight into the prognosis for the Formula One champion, who suffered critical head injuries when he fell and struck a rock on Sunday while skiing in the French Alps. Schumacher's condition stabilized somewhat after the second surgery, but he remains in a medically induced coma.

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"We cannot tell you any more about the future," said Gerard Saillant, a surgeon and friend of the family who is in Grenoble. Saillant said it would be "stupid" to make any predictions about Schumacher's recovery. However, Dr. Emmanuel Gay, the chief neurosurgeon at Grenoble University Hospital, said a brain scan performed late Monday showed bruising "a little everywhere" in Schumacher's brain, but also said the scan showed an unexpected easing of pressure.

The successful second surgery was to eliminate the largest and most accessible bruise on the left side of his brain. "We cannot say he is out of danger," Dr. Jean-Francois Payen, head of the hospital's intensive care unit, said. Payen said any neurological evaluation was currently "out of the question."