Everything You Need to Know About Different Types of Stroke
Types of Stroke
Stroke is a condition in which there is a disruption in the function of the brain due to problems with the blood supply. It may lead to the death of the brain cells, depending on the cause and the type of stroke.
The issue with blood supply may be an occlusion of a blood vessel leading to a type of stroke known as Ischemic stroke. Or the blood may leak out of a vessel leading to what is known as a hemorrhage. There is another type known as mini-stroke in which the symptoms resolve on their own, without causing a significant damage.
Now let's look at each type individually and see what happens in each type in detail.
This type of stroke accounts for 87% of all stroke cases. It occurs when a blood vessel supplying the brain is occluded by a blood clot. If the clot stays and keeps on obstructing the blood supply, it leads to the death of cells in that part of the brain.
Symptoms depend on the area of the brain affected, which may be a weakness of an arm or a leg, or the person may not be able to speak or see things. If the occlusion stays, it can result in permanent dysfunction of a part of body or disability.
The underlying problem in this type of stroke is usually fatty deposits in the vessel wall known as "atherosclerosis". So this type of stroke can be of two types.
In a few cases, a stroke may be due bleeding inside the brain. The bleeding is usually the result of a ruptured/torn blood vessel leaking into the affected area. The accumulation of blood can cause compression, swelling, and damage to the cells in the affected area.
If the bleeding is not stopped within a certain time, it may lead to cell death causing permanent disability for that individual. If the bleeding occurs in a large area of the brain, it can be fatal. There are usually three common reasons for this type of stroke.
TIA (Transient Ischemic Attack)
Sometimes the stroke symptoms resolve on their own without any treatment. Usually, they resolve within a few minutes to a few hours. If the symptoms resolve within 24 hours without any treatment, then it is known as TIA (Mini-stroke).
It usually occurs due to the same reasons as an ischemic stroke but the blood clot degenerates/dislodges or the obstruction resolves on its own.
It is important because it is actually a warning sign as the person who develops a TIA or a mini-stroke is at a much higher risk of developing a stroke in future. So, it is vital for the patient to be seen by a doctor in a hospital.
Depending on various factors, the doctor may decide to keep you in the hospital for observation. The doctor may carry out investigations just to make sure that there is no immediate risk to develop stroke in near future. Any abnormality found in blood pressure, or any investigations is dealt with promptly and the patient is usually routinely followed up.
Importance and Warning Signs
The important thing to remember is that a stroke is an emergency which can lead to a permanent disability and even death if not taken care of immediately.
The ischemic stroke can be treated and the damage can be prevented if you are seen by a doctor within few hours of when the symptoms started. So it is vital to be able to recognize the important warning signs. You should be alarmed if:
In case of any of these symptoms, you or any one close-by should call the ambulance IMMEDIATELY. Even if the symptoms resolve by the time ambulance arrives, still you need to be seen by a doctor and needs to be evaluated in a hospital.
Always remember the following 4 words.
F: Face Drooping
A: Arm/Leg weakness
S: Speech impairment
T: Time to call the ambulance
Stroke Risk Factors
It is important to look at the risk factors that may lead to a stroke and understand their importance so that necessary steps can be taken to modify them and prevent a stroke.
There are few factors which are not in anyone’s control. They are associated with a higher risk for stroke. The important thing is to recognize if you fall under a specific group and keeping a close watch for the other modifiable risk factors.
Types of Stroke Based on Anatomical Location
Following are the types of stroke based on their anatomical location:
Temporal Lobe Stroke
This is one of the four main areas of your brain. It is the size of a fist and extends from the temple to just behind the ears. It is presented on both sides of the skull. It is supplied by the middle and posterior cerebral arteries.
The temporal lobes on the left and right side are connected via corpus callosum (a bridge of nerve fibers that connects the right and left hemisphere of the brain).
Temporal lobe has a vital role in memory, language and perception. The temporal lobe is responsible for auditory, visual and long term memory. This lobe has the major function of speech comprehension.
Ischemic stroke in the temporal region involves the middle cerebral artery (MCA). This is a major artery and because of this ischemic stroke of MCA often affects other lobes of the brain along with temporal lobe.
The hemorrhagic strokes (Subarachnoid, intracranial, and intracerebral hemorrhage) in temporal lobes are mostly localized within the lobe.
Common symptoms of temporal lobe stroke include:
After the initial medical intervention, therapy plays a huge role in recovery of stroke patients. With vision, therapy basically focuses on compensatory therapy. Because vision once lost cannot be restored. Scanning techniques can help those patients that suffer from a visual field cut.
For language problems, speech and language therapy can vastly improve the survivor’s ability to understand and comprehend. Positive factor for recovery is that temporal lobe has the ability to rewire itself to the temporal lobe of the other side.
Parietal Lobe Stroke
Parietal lobe is one of the most important lobes in the brain. Parietal lobe is located above the temporal lobe and behind the frontal lobe. The parietal lobe receives its blood supply from middle, posterior, and anterior cerebral arteries. This lobe helps to provide communication and integration between different parts of the brain.
This is the reason that parietal lobe strokes have a profound effect, even if the stroke is relatively small. In the parietal lobe our brain creates our perception based on what we feel, hear and see. It is also responsible for analytical thinking.
The symptoms of parietal lobe stroke can be divided into 4 categories like visual, abnormalities in self-perception, sensory and others.
Common symptoms are:
Immediate medical intervention can help improve the prognosis for stroke patients. Intensive rehabilitation can help improve the life of parietal lobe stroke survivors.
Frontal Lobe Stroke
Frontal lobe, as the name suggests, is presented at the front of the skull. It extends from the forehead to a little past halfway of the skull. The frontal lobe contains many grooves and ridges. The frontal lobe has left and right segments. The frontal lobe makes up about one-third to half of the cerebral cortex. The anterior and middle cerebral artery supply this lobe.
The frontal lobe is enriched with dopamine sensitive receptors. They are involved in various tasks like reward, attention, motivation, inhibition, planning, and short-term memory. The frontal lobe communicates with various deeper structures of the brain to modify behavior. Using positive and negative reinforcement to modify behavior comes down to the frontal lobe.
Because the frontal lobe is a huge structure, the extent of damage is assessed by the size of bleed or ischemia. Stroke could affect a large part of the frontal lobe and cause a massive bleed and swelling or it can just affect a small part of the frontal lobe and have few deficits.
Following are the common symptoms of frontal lobe stroke:
The ability of a stroke patient to recover depends on the following factors:
- Your age
- Your health before the stroke
- Severity of the stroke
These factors impact the patient’s ability to recover. If the patient is old and has comorbidities then the chances of recovery decline. Initial medical intervention either through medications or surgery help pave the path of recovery.
After the initial phase of healing, therapy can help bridge the gap. Physical therapy can help with muscle weakness and speech and language therapy can help with aphasia.
Consulting a psychiatrist and seeking behavior therapy can help with personality and behavior changes.
Occipital Lobe Stroke
Occipital lobe is the posterior most lobe of the brain. It is located behind the parietal lobe. It has two segments - left and right - and is considered the smallest lobe of the cerebral cortex.
This lobe is mainly associated with vision. Because it contains the primary visual cortex. This lobe has various other functions that are vital for the proper functioning of the body. Occipital lobe is supplied by posterior cerebral artery.
In general, occipital lobe is the least common site of stroke. In other lobes of the brain (frontal, parietal, and temporal) mostly lobe of one hemisphere is affected. But in case of occipital lobe stroke can affect both the left and right occipital lobes.
The common symptoms of occipital lobe stroke are:
The recovery depends on the magnitude of stroke and early medical intervention. Proper and timely intervention of stroke patients can help cut down on the total recovery time. Visual loss is a permanent loss and it cannot be restored.
Compensatory and occupational therapy can help improve the quality of the survivor’s life.
The treatment goals usually depend on the type of stroke.
For ischemic stroke, the treatment goal is to dissolve or dislodge the clot.
Treatment with Medicines: First option is to treat it with a medicine known as tissue Plasminogen Activator (tPA). It is administered through a vein and the purpose is to dissolve the clot and improve blood flow to the brain. It can save lives and reduce long term effects of stroke.
It is important to administer it within 3 hours of having stroke or up to 4.5 hours in certain patients. Many people miss this key brain-saving treatment because they don't arrive to the hospital in time for therapy. This is the reason why it is so important to identify a stroke and seek treatment immediately for the best possible chance at a full recovery.
Physical Removal of Clot: It is another strongly recommended treatment option known as mechanical thrombectomy. In this procedure, surgeons use a device resembling a wire cage - known as stent retriever - to remove a large blood clot.
The procedure should be done within six hours of the onset of acute stroke symptoms. For selected patients under certain conditions, the procedure can be beneficial if done even within 24 hours of onset. Patients who are eligible for IV alteplase should receive the drug, even if the clot removal procedure is considered.
The good news is that around 80 percent of strokes in adults are preventable. However, after having a stroke once, the patient is at a high risk for having another one so the most important thing is to prevent another.
Life After Stroke
For a person who had a stroke recently, life can feel very scary and upsetting. First reason being that it usually happens unexpectedly and most of the time without a warning. If it leads to some disability or residual weakness, it may seem like the end of the world.
However, learning about the important physical, communication, behavioral and emotional effects that stroke can have on a survivor, and finding out how to improve and adapt is essential to make the most of the recovery process.
Stroke can lead to limitation relating to any part of the body, maybe a limb or the swallowing, but continued work towards recovery is important.
Physical, rehabilitative, occupational, psychological, behavioral and psychosocial therapies and support is essential to help a person lead a fulfilling life after a stroke.
It is important to never hesitate in asking for help. Making good rehab decisions and taking steps to prevent a second stroke may improve quality of life.
Making good rehab decisions and taking steps to prevent a second stroke may improve quality of life.