GRENOBLE, France (AP) — Doctors treating Michael Schumacher say the Formula 1 champion was showing surprising improvement that allowed a second surgery for head injuries he suffered during a ski accident, but cautioned that his brain still had extensive bruising.

Schumacher was skiing with his son when he fell and struck a rock Sunday in the French Alps.

"There are hematomes a little bit everywhere," said Dr. Emmanuel Gay, describing the extensive bruising throughout Schumacher's brain. But Gay said surgeons decided upon a second operation after Schumacher's unexpected, though small, improvement on Monday.

They offered no predictions Tuesday on whether or when they would bring him out of an induced coma, intended to relieve swelling.

"We cannot tell you any more on the future," said Gerard Saillant, a surgeon and friend of the family.