Interpreting Stroke and ways to manage Stroke
A stroke is a medical condition that arises when the blood supply to the brain is abruptly interrupted. When the blood supply is cut off, the part of the brain that no longer receives oxygen does not function correctly, and as a result, the brain cells are at in serious risk of dying due to lack of oxygen. While the effects of a stroke depend primarily on which part of the brain is affected, it is, indeed a very severe condition that requires immediate medical attention.
Types of Stroke
Not all strokes are the same, which is why the treatment and recovery for them are also different. Strokes generally fall into two categories – Ischemic Stroke and Hemorrhagic Stroke. Both of these categories can be further sub-classified into two other types of strokes.
Types of Ischemic Strokes
An Ischemic Stroke is also known as Brain Ischemia or Cerebral Ischemia and is usually caused when the artery that supplies blood to the brain is blocked. These strokes account for about 87% of all strokes and can be further classified into two kinds.
- Embolic Stroke
This is a type of Ischemic Stroke where an artery in the brain becomes blocked. An Embolic Stroke occurs when a blood clot from some other part of the body breaks loose and travels via the bloodstream to the brain where it then blocks an artery.
- Thrombotic Stroke
This type is also an Ischemic Stroke and occurs when the blood clot originates in an artery within the brain itself. The blood clot, or thrombus, is caused due to fatty deposits, or plaque, lining the artery walls, and this condition is known as atherosclerosis. It is generally observed in patients with high cholesterol levels. The plaque reduces the diameter of the artery and causes a blood clot to form, which then blocks the artery entirely.
Types of Hemorrhagic Strokes
A Hemorrhagic Stroke occurs when an already weakened blood vessel ruptures and bleeds into the brain. The compression from the accumulated blood on the surrounding tissues of the brain leads to a Hemorrhagic Stroke.
- Intracerebral Hemorrhage
This type of stroke is caused when an artery in the brain bursts and leaks blood into the surrounding brain tissue. The bleeding causes the brain cells to die, and that part of the brain stops working as it should. Hypertension, or high blood pressure, is one of the main causes of this type of stroke.
- Subarachnoid Hemorrhage
This type of Hemorrhagic Stroke occurs when a blood vessel bursts on the surface of the brain, as a result of which the blood leaks into the space between the brain and the skull. The blood collected here begins to put pressure on the blood tissue and causes blood vessels to spasm. Generally, one of the most common causes of subarachnoid hemorrhage is due to a burst aneurysm.
Treatment of stroke
Timely treatment of stroke can save lives and also prevent a person from being disabled for life. However, treatment largely depends on what the nature of stroke is – whether it is an Ischemic Stroke or Hemorrhagic Stroke. Here is how each of these strokes can be effectively treated.
Ischemic Stroke and TIA
An Ischemic Stroke occurs when a fatty substance called plaque gathers in the arteries and narrows down the blood flow to the brain. The artery gets blocked as a result of the blood clots.A Transient Ischemic Attack or TIA is a mini-stroke which falls under the category of ischemic strokes. TIA is a temporary blood vessel blockage that lasts twenty-four hours or just for a couple of minutes. However, the symptoms are the same as an Ischemic Stroke.
Ischemic Stroke and TIA are treated by removing any obstruction to restore blood flow into the brain. The recommended and approved medication for this kind of stroke is the use of Tissue Plasminogen Activator, which has to be administered within a window of three hours from the onset of stroke symptoms for it to work best. Unfortunately, only 3 to 5 % of stroke victims reach the hospital in good time for this kind of treatment, making the actual use of Tissue Plasminogen Activator to be considerably low.
Clot Breaking Drugs
Certain drugs administered during a stroke, in this case, known as tissue plasminogen activator (tPA), act as clot breaking drugs. Used in a stroke emergency, tPA is injected into a patient’s vein to break up a blood clot. This drug is always given via intravenous (IV) and not by mouth. However, tPA cannot be administered to people who are at high risk of bleeding.
This is used to treat stroke patients and involves the use of minimally invasive procedures where an interventional radiologist used modern technology to remove blood clots from the arteries that prevent blood flow to the brain.
Stents are tiny tubes made of either plastic or metal that doctors use to insert into a blocked passageway to keep it open. The stent afterward restores blood flow into the brain. The doctor uses angiography to insert a catheter that is threaded through the arteries depending on the location deemed to be best for stent placement.
If the area affected by a stroke happens to bleed much, a doctor may perform a surgical operation to remove the blood while relieving pressure on the brain. Surgery usually involves opening up an artery that has been narrowed by plaque. The most common type of surgery involves a procedure of Carotid Endarterectomy, which is done to remove plaque along the carotid arteries that run along the sides of one’s neck.
A Hemorrhagic Stroke occurs when a weakened blood vessel bursts and starts to bleed into the brain. The leaked blood exerts pressure and ends up causing damage to the blood cells.This type of stroke needs surgery to relieve the pressure on the brain that results from bleeding. This involves surgical treatment to prevent additional strokes that are caused by a ruptured blood vessel or an aneurysm.Treatment for these kinds of strokes does not involve the use of blood thinners or anticoagulants, since thinning the blood would only worse the bleeding inside the brain. For people who are already under prescribed blood-thinning medicines, the doctor might administer counter effect drugs to slow the bleeding process.
A relatively newer method to treat strokes, coiling, treats aneurysms- both ruptured and unruptured, by isolating the affected aneurysm or AVM and keeping it away from the area of healthy blood circulation. It is a minimally invasive procedure that uses a catheter to reach the affected site, introduce a platinum coil, and block normal blood from flowing into that area.
This involves a surgical procedure conducted under general anaesthesia, where a piece of the patient’s skull is removed to locate the aneurysm in the brain tissue. A clamp is then placed at its base to prevent bleeding or re-bleeding. At the end of the procedure, the piece of skull is replaced.
Surgery is performed to seal any defective blood vessel, and blood flow is redirected to other vessels supplying blood to the same brain region. In case a patient has a ruptured cerebral aneurysm, the aneurysm is surgically eliminated at first. At some point during this period, cerebral angiography is conducted to document the elimination of the aneurysm.