Doctors at the hospital where he is being treated in Grenoble said they carried out a new scan on Monday after it appeared the pressure on the Formula One legend's brain had improved.

The scan indicated that his condition was relatively stable and the lesions on the brain had not worsened.

"We decided that since there was an improvement, we would do this operation," one of his doctors said. The operation was to remove a haematoma in Schumacher's brain.

"We didn't originally think we would do this operation, lbut it enabled us to reduce further the pressure on the brain.

"We did this overnight with a relatively good result. This morning we did some more scans and we noticed we have removed the haematoma further, which gives us signs that the situation is better controlled than yesterday.

"Of course we spoke to the family too [before the operation], because it's a difficult decision to make after this kind of brain trauma."

Schumacher improved overnight after the two-hour operation. Doctors said they were "quite surprised" by the improvement Schumacher showed during the day and by the result of the scans, which showed the haematoma had reduced.

"It was on the left side of brain and different to the other haematomas removed yesterday - it was in the brain itself."

But Schumacher was still in a critical condition in an artificial coma and doctors could not predict what would happen.

"The scans showed the haematoma was correctly removed but there were other lesions on the brain and these lesions need to be kept in check ... every hour.

"The situation is better controlled than yesterday but we can't say he is out of danger ... we gained a bit more time ... and the hours to come are still crucial to the outcome."