"He is doing better than yesterday," one of the doctors treating him at the CHU hospital in the southeastern French city of Grenoble told a press conference on Tuesday morning.
But the medical team said it was still too early to give a prognosis. They added the next few hours would be crucial.
"We are surprised by the improvement," one doctor said, adding that the medical team had "gained some time".
The operation to remove a blood clot in the brain took around two hours and was carried out at 10pm on Monday.
Surgeons only went ahead with the operation after consulting Schumacher's family, who took the "difficult decision" to agree to a new procedure.
Jean-Francois Payen, head of the intensive care unit, told reporters that Schumacher was still in danger. "We cannot speculate on the future," he said.
Schumacher's wife Corinna and children Gina Maria and Mick are by his side and a small crowd held a night vigil outside the hospital, an AFP reporter said.
A source close to the investigation into the off-piste accident at upmarket resort of Meribel told AFP that Schumacher's helmet was smashed "in two" by the impact.
Schumacher's family in a statement expressed their thanks to the doctors who they said were doing "everything possible to help Michael" and to well-wishers around the world. The family also asked the press to "respect their privacy," in the statement put out by Schumacher's spokeswoman Sabine Kehm.
Neurosurgeon Stephan Chabardes, who operated on Schumacher, had earlier said medical updates would be provided as and when necessary.
"It usually takes 48 hours, or even longer, to be able to formulate an opinion" on injuries of this severity, said neurologist Jean-Luc Truelle.
At a press conference on Monday doctors said the seven-time Forumula One champion would have died if he had not been wearing a helmet.
"If someone had had this type of accident without a helmet, they would definitely not have survived," one of the doctors treating him at the hospital in the southeastern French city of Grenoble told reporters.
"He is in critical condition, his condition can be described as life threatening," Jean-Francois Payen, head of the intensive care unit said during a press conference on Monday. The 44-year-old had suffered "diverse brain injuries".
Stephan Chabardes, the professor who operated on Schumacher, said the former racer arrived in hospital Sunday in an agitated state -- his arms and legs jerking uncontrollably -- and was not able to answer questions.
His condition "rapidly deteriorated" and he fell into a coma, he told reporters. Payen said he was immediately operated on and still suffered from "serious and diffuse brain lesions", which indicates his injuries are not localized but more widespread.
Dr Christoph Specht, a doctor analyzing the press conference for the n-tv broadcaster, said the comments made by his French colleagues in Grenoble suggested Schumacher was seriously injured.
"He is in a critical condition," the French doctors repeated. They confirmed they had operated on Sunday to try to reduce the swelling and pressure on Schumacher's brain, and were keeping him in a coma to try to gain control over the situation.
"We have to avoid all external stimuli and ensure that his brain is getting enough oxygen," said one of the team of medics at the press conference.
"It is much too early to make any prognosis on his progress or any long term development," they stressed.
After the accident Schumacher was airlifted to a local hospital, then to the Grenoble facility. A specialist neurosurgeon from Paris was rushed in to oversee his treatment.
The director of the Meribel resort, Christophe Gernigon-Lecomte, had said just after the accident that Schumacher had been wearing a helmet and was "conscious but a little agitated" immediately after the accident, suggesting he had not received life-threatening injuries.
But when Schumacher then fell into coma, doctors realized the damage was worse than initially feared.
"My thoughts are with Michael Schumacher at this tough time.. Michael more than anyone has the strength to pull through this," tweeted British F1 driver Jenson Button.
Schumacher's former teammate at Benetton Martin Brundle wrote on Twitter: "Come on Michael, give us one of those race stints at pure qualifying pace to win through, like you used to. You can do it."
He added that the German was "a crazy brave skydiving/bike racing daredevil".
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