Speaking to reporters outside the Hadassah hospital, doctors gave an upbeat prognosis for the 77-year-old despite earlier announcements on Saturday that his condition remained critical.
Results of the latest scan on Saturday stirred cautious optimism in the Israeli media.
Felix Umansky, the Argentinian surgeon, told AFP. "The scan is better than yesterday's. I am more optimistic.
"Ariel Sharon is in a stable condition and given his situation, this is good news."
Doctors said it could still be a couple of days before they knew how much damage Sharon, who is heavily sedated, had suffered as a result of the stroke. But the medical consensus is that if he survives, it is extremely unlikely he will ever return to work.
Tests earlier in the day also detected an abnormality in the area of Sharon's lungs Israeli television reported.
Israel's state-run Channel One said doctors did not know the cause of the condition, which was found in an X-ray. The television report said stroke victims often develop lung infections or pneumonia.
"There is always damage in cases like these"
Umansky said: "There is always damage in cases like these. We have to wait to see how he will react when we lessen the dosage of the medications that are keeping him sedated."
But he told AFP that Sharon could still recover. "He can still pull through," he said. "He is doing better. We need to wait two or three days. We are going to do another scan and if there are no other problems we will start to bring him out of the coma."
However, doctors have said privately that Sharon may have suffered irreversible brain damage, leaving the future of Israeli politics hanging in the balance. His closest allies have acknowledged that he is unlikely ever to return to office.
In the event of Sharon dying or being permanently incapacitated, Ehud Olmert, Sharon's deputy and finance minister who has taken over temporarily as prime minister, will have to be approved as acting prime minister by a cabinet vote.
Olmert held talks with Shimon Peres, the former prime minister and a Sharon ally, on Friday. It was speculated that he would ask Peres to rejoin the government as an elder statesman in the absence of Sharon.