STROKE OR BRAIN ATTACK

A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functioning properly. Signs and symptoms of a stroke may include an inability to move or feel on one side of the body, problems understanding or speaking, dizziness, or loss of vision to one side. Signs and symptoms often appear soon after the stroke has occurred. If symptoms last less than one or two hours, the stroke is a transient ischemic attack (TIA), also called a mini-stroke. A hemorrhagic stroke may also be associated with a severe headache. The symptoms of a stroke can be permanent. Long-term complications may include pneumonia and loss of bladder control.

The main risk factor for stroke is high blood pressure. Other risk factors include tobacco smoking, obesity, high blood cholesterol, diabetes mellitus, a previous TIA, end-stage kidney disease, and atrial fibrillation. An ischemic stroke is typically caused by blockage of a blood vessel, though there are also less common causes. A hemorrhagic stroke is caused by either bleeding directly into the brain or into the space between the brain's membranes. Bleeding may occur due to a ruptured brain aneurysm. Diagnosis is typically based on a physical exam and supported by medical imaging such as a CT scan or MRI scan. A CT scan can rule out bleeding, but may not necessarily rule out ischemia, which early on typically does not show up on a CT scan. Other tests such as an electrocardiogram (ECG) and blood tests are done to determine risk factors and rule out other possible causes. Low blood sugar may cause similar symptoms.

TYPES OF STROKE

• Ischemic
• Hemorrhagic
• Transient Ischemic Attack (TIA).

Ischemic: Ischemic stroke occurs when an artery to the brain is blocked.  The brain depends on its arteries to bring fresh blood from the heart and lungs. The blood carries oxygen and nutrients to the brain, and takes away carbon dioxide and cellular waste. If an artery is blocked, the brain cells cannot make enough energy and will eventually stop working.

Ischemic stroke can be divided into two main types: thrombotic and embolic.

Hemorrhagic: Hemorrhagic strokes make up about 13 percent of stroke cases. It’s caused by a weakened vessel that ruptures and bleeds into the surrounding brain. The blood accumulates and compresses the surrounding brain tissue.

There are two types of hemorrhagic stroke: Intracerebral hemorrhage and subarachnoid hemorrhage 

Transient Ischemic Attack: A transient ischemic attack (TIA) is a medical emergency. It is defined as a transient episode of neurologic dysfunction due to the focal brain, spinal cord, or retinal ischemia, without acute infarction or tissue injury. The definition of a TIA has moved from time-based to tissue-based. A TIA typically lasts less than an hour, more often minutes

• Stroke or Brain Attack is a disease that involves the blood vessels that supply blood to the brain.
• A stroke occurs when a blood vessel that brings oxygen and nutrients to the brain ruptures or is clogged by a blood clot or some other mass.

Regards

Meria Den

Managing Editor

Journal of Stroke Research & Therapy.