Stroke

Common sites for intracranial hemorrhage are the

Thalamus and basal ganglia

A stroke occurs when

A blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot, or bursts (or ruptures).

What happens when a blood vessel or clogged or bursts?

A part of the brain cannot get the blood (and oxygen) it needs, and brain cells die.

An ischemic stroke may be caused by

A thrombosis or embolism

Factors influencing recovery on hemorrhagic strokes

Amount of damaged brain tissue, site of the infarct, recovery rate varies.

Risk factors of hemorrhagic strokes include

Atherosclerosis, family history, smoking, prior aneurysm, gender, race, and high blood pressure

Stroke effects on receptive language

Auditory comprehension, and understanding

Intracerebral hemorrhage

Bleeding is in brain tissue (aphasias)

What are the physiological effects of a stroke?

Blood deprived neurons die within the first few hours following the stroke. There is swelling of damaged brain tissue Intracranial pressure may elevate if there is damage to a large area of the brain causing displacement of brain tissue to other parts of the brain. Blood flow diminishes. Brain tissue at the site of the stroke receive released neurotransmitters and neurotoxins as do other parts of the brain and cerebral spinal fluid. This may contribute to reduced cerebral blood flow and an upset in neuron metabolism.

Diaschisis

Brain action is disrupted in areas away from the site of the damage but connected through neuronal pathways.

Hemorrhagic Stroke/Cerebral hemorrhage

Caused by bleeding, rupture (burst) and weakness of a blood vessel wall, or by traumatic injury to a blood vessel.

What does CVS stand for?

Cerebrovascular accident

What factors influence recovery on ischemic strokes

Greatest chance for recovery is in the first two weeks. People with middle severity ranges have greatest recovery during that time. People with mild severity usually have little damage to recover. Impairment lasting beyond two-four weeks usually indicates considerable destruction of brain tissue leaving a person with increased impairments.

Physiological effects such as Diaschisis, Denervation Sensitivity, and Transneural Degeneration may produce

Impairments in the brain action, mental status and behavior

What factors influence recovery on hemorrhagic strokes

Little improvement is seen following the first few weeks post stroke, but then show rapid improvement. Following the rapid improvement, recovery slows down and stabilizes. Neurologic recovery usually complete by six months following stroke onset. Amount of damaged brain tissue.

Transneural Degeneration

Lost connections in the brain cause I damaged parts of the brain that connect with damaged neurons to degenerate.

Denervation Sensitivity

Neurons that have survived, but have lost some of their input from the injured neurons become hypersensitive to remaining input from the damaged area

Ischemic/Occlusive Stroke

Occurs when the brain is deprived of blood, caused by blocked artery and brain loses part of its blood supply. Brain tissue is likely to die if supply is cut more than 3 to 5 minutes.

Stroke effects on reading

Oral and comprehension

Aneurysm

Pouch found or bulge found in weak area of an arterial wall that provides blood to the brain. Rupture causes a subarachnoid hemorrhage. If detected prior to rupture, may be alleviated surgically.

What is a stroke?

Stroke is a generic term for brain damage caused by vascular disruptions (loss of blood supply or bleeding) in the brain.

What are the signs and symptoms of a stroke?

Sudden or abrupt numbness or weakness on one side of the body in the face, arm, or leg. Sudden or abrupt confusion, difficulty speaking or understanding speech. Sudden or abrupt difficulty seeing in one or both eyes. Sudden difficulty walking, dizziness, loss of balance, and/or lack of coordination. Sudden or abrupt severe headache with no known cause and/or with other stated symptoms.

Transient Ischemic Attacks (TIAs)

Temporary disruption of cerebral circulation that are caused by a clot. This small emboli may temporarily occlude an artery and then dissolve. Thrombus that doesn't completely occlude an artery affect blood pressure. Cerebral vasospasm of an almost completely occluded artery (walls contract).

Stroke effects on expressive language

Verbal (spontaneous, repetition, and imitative) language, written language, and gestures.

Extracerebral hemorrhage

bleeding is outside the brain (meninges or on surface of brain)

Risk factors for stroke are

• High blood pressure • High Cholesterol • Smoking and Tobacco Use • Excessive Alcohol Use • Physical Inactivity • Diabetes • Heart Disease • Abnormal Heart Rhythm

Physiological Effects of TIAs

• Limb weakness or numbness • Visual anomalies • Disturbance in speech • Symptoms occur rapidly • Symptoms endure a short time. • Resolution is a few minutes to 24 hours. • The majority of TIAs last less than five minutes; the average is about a minute. • TIAs do not usually cause permanent brain injury