Doctors treating Israeli Prime Minister Ariel Sharon expect to decide on Sunday about when they will bring him out of a coma they induced medically after he suffered a huge stroke.

Dr. Jose Cohen, one of the neurosurgeons who has been treating Sharon at the Hadassah hospital in Jerusalem, called it "the day of truth."

The medical team would have to slowly reduce Sharon's anesthesia to allow him to wake.

Neurosurgeon Dr. Jose Cohen at the Hadassah hospital. (AP File Photo)
Neurosurgeon Dr. Jose Cohen at the Hadassah hospital. (AP File Photo)

Cohen said doctors would only then be able to assess the extent of brain damage caused by the stroke, which occurred on Wednesday.

"We will all know if what we have done so far has helped," he told Israel's Channel 2 television.

An update on Sharon's condition was expected on Sunday.

Dr. Shlomo Mor-Yosef briefs the media about Sharon's condition outside the hospital on Saturday. (AP Photo)
Dr. Shlomo Mor-Yosef briefs the media about Sharon's condition outside the hospital on Saturday. (AP Photo)

In the meantime, acting prime minister Ehud Olmert was leading the weekly cabinet meeting.

Doctors have operated on Sharon three times since Wednesday to curb brain swelling and stop bleeding.

Israeli PM will likely have 'cognitive problems': doctor

Cohen told Channel 2 on Saturday that he was "quite optimistic" about Sharon's prospects for survival.

But he warned it appeared certain that Sharon's ability to think and reason had been damaged.

"To say after such a severe trauma as this that there will be no cognitive problems is simply not to recognize the reality."

Hospital director Dr. Shlomo Mor-Yosef said on Saturday that the latest brain scan showed "very slight signs of improvement" over previous tests.

The test indicated that Sharon's intracranial pressure, blood pressure and pulse were "within normal range," and that his condition remained stable but critical, said Mor-Yosef.

He said the brain swelling had eased slightly, and the left side "looked better than" the right side, the doctor said.

Doctors said they managed to halt the bleeding and relieve pressure that had built up in his skull in the wake of the cerebral hemorrhage.

Aides and doctors have said that even if the Israeli leader survives, the irreversible brain damage he probably has suffered would preclude a return to his duties.