Acute Ischemic Stroke


Stroke is defined as loss of brain function due to disturbance in blood supply to
the brain. This can be due to lack of blood flow caused by blockage which may be due to
thrombosis, arterial embolism, or a haemorrhage (leakage of blood) As a result, the affected
area of the brain is unable to function, which might results in inability to move one or more
limbs of the body, inability understand speech, or an inability to see one side i.e. visual
disturbance . stroke may cause permanent neurological damage, complications, and death.

Strokes can be classified into two major categories: ischemic and
hemorrhagic. Ischemic strokes are those that are caused by interruption of the blood supply,
while hemorrhagic strokes are the ones which result from rupture of a blood vessel or
an abnormal vascular structure. About 87% of strokes are caused by ischemia, and the
remainder by hemorrhage.

Ischemic stroke

Strokes can be either ischemic or hemorrhagic. In an ischemic
stroke, the blood supply to part of the brain is cut off because blood clot or some
form of plaque stops blood supply to brain Blood clots can travel to the brain from
another artery (artery-to-artery embolization) or they can come from the heart
(cardioemblic stroke).

Ischemic strokes can be caused by a blockage anywhere along the arteries
feeding the brain. The blockages can occur for a variety of reasons, including:

The formation of fatty material (atheroma) along the walls of an artery,
which reduces blood flow

Breaking off of atheroma from the artery wall. The material can flow with
the blood and become stuck in a smaller artery, causing a blockage.

Blood clots that break loose from the heart or one of its valves, known as
an embolus. The clot can travel up the arteries of the brain and lodge there,
causing an embolic stroke or cerebral embolism.
This type
of stroke is most common in people who have recently had heart surgery
and in people who have defective heart valves or abnormal heart rhythms
(especially atrial fibrillation).

Inflammation or an infection that narrows blood vessels that lead to the

Consumption of Drugs, such as cocaine and amphetamines, which can
also narrow the blood vessels

Strokes may also cause swelling in the brain. The
pressure that results can damage brain tissue more, making neurologic problems

worse, even if the stroke itself does not enlarge.