Ischemic stroke, characterized by the death of brain tissue due to inadequate blood and oxygen supply caused by blocked arteries, often sends warning signals before its onset. Typically, strokes occur when an artery in the brain is obstructed by a blood clot or fatty deposits resulting from atherosclerosis.
Symptoms that manifest suddenly include muscle weakness, paralysis, loss of sensation on one side of the body, changes in speech, confusion, blurred vision, dizziness, loss of balance, and coordination. Diagnosis is usually based on sudden symptoms, physical examination findings, and brain imaging. Additional tests like computed tomography and magnetic resonance imaging, along with blood tests, may be conducted to determine the stroke’s cause.
Treatment approaches involve medications to dissolve clots or minimize clot formation, coupled with procedures to break up clots. Post-treatment, rehabilitation plays a crucial role in recovery. Preventative measures encompass managing risk factors, taking medications to reduce the likelihood of blood clots, and, in certain cases, undergoing surgery or angioplasty to address blocked arteries. Following a stroke, approximately one-third of patients experience a significant recovery of their functional abilities.
Causes of Ischemic Stroke:
The primary cause of a stroke is typically the blockage of an artery supplying blood to the brain, often branches of the internal carotid artery. This blockage leads to a lack of blood supply, causing brain cells to die if deprived for an extended period, typically around 4.5 hours.
Blood is delivered to the brain through two major arteries – the internal carotid arteries in the front of the neck and the vertebral arteries in the back. The vertebral arteries unite within the skull, forming the basilar artery at the back of the head. The internal carotid and basilar arteries branch into various arteries, including the cerebral artery. The circle of Willis connects the internal carotid artery and the cerebral artery, while the vertebral arteries connect with each other. Collateral arteries, running between other arteries, create additional connections, including those connecting the circle of Willis with branching arteries. These collaterals play a significant role in preventing strokes, depending on their size and effectiveness in maintaining blood flow when one artery is blocked.