Just like a heart attack occurs due to reduced supply of oxygen to the heart a stroke or a brain attack happens when oxygen supply to an area of the brain is cut off. This happens when the flow of blood that carries oxygen is disrupted or blocked. A stroke is a medical emergency because within minutes brain cells of the affected area begin to die. In simple terms, the faculties controlled by the damaged cells are lost.
A mild stroke may only manage to weaken muscles or memory controlled by the affected brain cells. A major stroke on the other hand results in more serious problems such as permanent disability and paralysis. Over 65% of those who survive major strokes are left with some kind of disability.
Strokes can be of two kinds- the more common ischemic stroke and haemorrhagic stroke. Ischemic stroke is caused by the clogging of a blood vessel by a blood clot. Haemorrhagic stroke occurs when a ruptured blood vessel starts bleeding into the brain. Another kind of stroke called transient ischemic attack, also called mini-strokes, occur when blood supply to the brain is cut off briefly.
People who are obese, over 55 years of age, lead a sedentary lifestyle, heavy drinkers, smokers and drug users or those who have a family history of stroke are more vulnerable to suffering a stroke.
The incidence of ischemic stroke is around 85% of all strokes making it the most common one. It is caused clogging or narrowing of arteries that supply to the brain. This condition of reduced blood supply is called ischemia. Blood clots are mostly responsible for these blockages and many times originate from fatty deposits or plaque within the arteries. With age, our arteries naturally constrict but factors such as smoking, high blood pressure, high cholesterol levels, excessive uptake of alcohol and a family history of diabetes and heart attack can dangerously accelerate the process. Atrial fibrillation or irregular heartbeat can also lead to formation of blood clots.
A haemorrhagic stroke is caused by ruptured arteries that start leaking blood into the brain. The leaked blood damages the cells and they die. The most common cause of haemorrhagic stroke is hypertension. Other reasons are blood thinning medications, trauma and weak blood vessel walls (brain aneurysm). A traumatic brain injury can also cause bleeding in the brain leading to the formation of a blood clot. Obesity, smoking, consumption of excessive alcohol, sedentary lifestyle and stress also contribute to chances of stroke.
Haemorrhage can be intracerebral or subarachnoid. An intracerebral hemorrhage is more common and it occurs when brain tissue is flooded with blood. Subarachnoid hemorrhage is the occurrence of bleeding between the brain and the thin tissue covering it.
A transient ischemic attack or a “mini stroke” is caused by the brief disruption of blood flow to the brain often for less than five minutes due to a blocked artery. TIAs are like warning signs for future major strokes so they should not be taken lightly.
A person experiencing the onset of a stroke suddenly feels the limbs and the face on one side of the body going numb. Speech becomes garbled and the person is unable to see from one or both eyes. If the person is standing or walking, there is a sudden loss of balance and coordination of the body. A sudden headache may also mark the start of a stroke.
The extent of neurological involvement may range from mild motor deficit to gross involvement of various functions namely sensorimotor, perceptual, emotional, behavioural, memory intelligence, speech and language function, ultimately affecting daily activities.
A person suffering from stroke or showing any symptoms should immediately be given medical treatment. Ischemic strokes are treated first by giving aspirin to reduce the risk of a second stroke. Drugs such as alteplase that break down clots and keep more from forming may also be given to prevent symptoms such as paralysis. A procedure called carotid endarterectomy is done to surgically open the carotid artery and remove the fatty plaque that is blocking the vessel. Angioplasty may also be done to insert a stent that prevents the artery from narrowing again.
In case of a haemorrhagic stroke, the focus is on reducing internal bleeding and reducing pressure on the brain exerted by the blood. Drugs may be given to reduce internal pressure, prevent convulsions and sudden blood vessel constriction. Surgery is used to repair blood vessels and remove arteriovenous malformations within the brain. These malformations are tangled arteries and veins that can rupture more easily.
Once a stroke has damaged the brain, it cannot be undone. Recovering completely is difficult but a good diet and exercise will improve the patient’s condition to some extent. Rehabilitation is the most important step in stroke treatment. Speech therapy, physiotherapy, occupational therapy, psychiatric sessions to address mental health and familial support go a long way in helping the patient cope.
Stem cell therapy is being actively considered as a potential treatment for stroke. Stem cells have the potential to self-multiplicate, differentiate, move to the affected area, regenerate and repair the tissues damaged by stroke.
There may be a possibility of using mesenchymal stem cells for stroke therapy. Mesenchymal cells are suitable as they can be obtained readily from bone marrow under local anesthesia, are easily expanded by culture, and could be delivered to injured brain tissue without invasive surgery. Furthermore, immune rejection can be prevented because the patient’s own cells are being used.
After stem cell therapy, our patients show remarkable improvements in several symptoms such as hand functions and activity of upper limbs, activity of lower limb, activity of trunk, higher mental functions/speech,balance, ambulation and activities of daily living. According to our patient studies, 51.8% of patients showed significant improvements, 29.6% of patients showed slight improvements, mild improvements were seen in 11.1% of the patients, promising a better future they deserved.
As observed in the PET-CT scans, the stem cells administered during the course of the therapy work wonders while repairing the damaged stroke affected regions of the brain by increasing their metabolism.