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  Experts: Sharon eye-flickering no real signDoctors say it's too soon to say if Israeli leader waking from comaBy Peggy Peck  Ariel Sharon, seen here in a 2004 photo, has been hospitalized since a major stroke on January 4. RELATED
YOUR E-MAIL ALERTSReports that Israeli Prime Minister Ariel Sharon's eyelids flickered as he recovers from a major stroke isn't a sign that he is waking from his medically induced coma, medical experts said. Sharon aides said the 77-year-old prime minister reportedly opened his eyes briefly when a tape of his grandson's voice was played, but a statement from Hadassah Hospital denied his eyes had fully opened. Experts said that eye-flickering shouldn't be taken as a sign that Sharon is regaining consciousness. Dr. Roger Smith, a professor of neurosurgery at Louisiana State University School of Medicine who practices at the Ochsner Clinic in New Orleans, said that eye movements, such as those reported about Sharon, are "brain stem reflexes, which tells us that the brain stem is still functioning but this is not a sign that the patient is waking up." For recovery from a coma after the type of major stroke Sharon had, it could be weeks or months before he stirs spontaneously, experts say, if he stirs at all. Dr. Michael Williams, associate professor of neurology and neurosurgery at the Johns Hopkins School of Medicine, said that "strictly speaking, the definition of stroke is when the eyes don't open in response to painful stimuli." Eye-flickering can be an early sign of awakening, Williams added, "but it is too soon to tell if that is the case." "If this motion is repeated in a pattern and evolution of responses over time, it may indicate awakening," he said. "But it may be nothing more than a reflex, and at this time that would be my suspicion." Doctors at Hadassah Hospital used sedatives to induce a metabolic coma in Sharon after he suffered a massive hemorrhagic stroke on January 4. The metabolic coma helped reduce pressure in the brain, which could cause additional injury. Since his stroke, Sharon has undergone three brain operations to stem the bleeding, drain blood and reduce swelling of the brain. Last week, doctors began to reduce the sedatives to awaken him from the coma. They reported that Sharon moved his right and left hands and his right leg in response to stimulus. The movement on the left side is significant because the stroke was on the right side of the brain, which controls movement on the left side of the body. On Saturday, the Israeli doctors stopped all sedation and removed a tube used to drain brain fluid. On Sunday, doctors performed a tracheotomy to help Sharon breathe while he was weaned off ventilator support. Smith said that coma awakening is usually graded using the Glasgow Coma Score, which measures three areas: eye, verbal and motor responses. The highest eye response score occurs when patients spontaneously open their eyes, but eye opening in response to verbal command is also considered a good sign. "If we just concentrate on eye opening, then sustained, semivoluntary eye opening would be a good sign, but blinking would be reflexive and not have true meaning in terms of awakening," he said. Smith said that it frequently takes at least a week to bring a patient out of a metabolic coma. "Once the effect of the drug wears off, it could still take weeks to months -- depending upon the amount of brain damage -- to recover from coma," he said. Sharon's stroke was his second in less than a month. On December 18, he had a mild one caused by a blood clot in his brain. Following that stroke, his physicians put him on a blood thinner. Use of blood thinnerIsraeli media reports have raised the question of whether the blood thinner contributed to the second stroke. They reported that Sharon had cerebral amyloid angiopathy, a condition that makes the blood vessels in the brain fragile and leaky. His doctors confirmed that they had diagnosed cerebral amyloid andiopathy in mid-December when Sharon suffered a mild ischemic stroke. About 75 percent of hemorrhagic strokes are caused by high blood pressure, but cerebral amyloid angiopathy, or CAA, is the second leading cause of hemorrhagic stroke, said Dr. Robert Felberg, director of the stroke program at the Ochsner Clinic. Felberg said that blood thinners are generally not given to patients with CAA because of the risk of bleeding in the brain. Sharon also was diagnosed with a congenital heart defect, considered a risk factor for another ischemic stroke, and doctors reportedly decided that the need to prevent another blood clot took precedence over the risk of hemorrhage. Dr. Larry Goldstein, director of the Duke Center for Cerebrovascular Disease in Durham, North Carolina, agreed that blood thinners are usually ruled out in such cases. But he added that it is not unusual to discover CAA in a patient who has had an ischemic stroke and therefore the treatment is not straightforward. "At that point, there has to be a careful assessment of the risk of hemorrhage against the risk of ischemic stroke," Goldstein said. 
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