A brain stroke a loss in brain function due to stoppage / interruption of normal blood supply. As blood flow is reduced / stopped, the brain cells do not get their required oxygen and nutrients and rapidly begin to lose function.
What are the symptoms of stroke ?
A stroke can present as a temporary or long lasting loss of consciousness, an inability to speak or move limbs. Sudden loss of vision. These symptoms improve after few minutes or hours, but should not be neglected.
What are the risk factors for having a brain stroke ?
Some risk factors for stroke can be :
Smoking or consumption of tobacco in any form.
Atherosclerosis.
High blood pressure.
Heredity.
Obesity.
Lack of exercise.
High cholesterol levels.
How is carotid artery disease diagnosed ?
If you have any of the risk factors for stroke, your doctor can examine you and have you screened for carotid artery disease.
This can be done by having a Colour Doppler Ultrasound of your neck vessels. A narrowing can be detected. However, ultrasound can only examine the neck vessels and would not be able to look for a narrowing of the carotid after the artery enters the skull.
CT Angiogram : Can accurately detect narrowing of the carotids right from the origin all the way inside the brain. Its disadvantage is that is requires exposure to radiation and an injection of contrast material.
MR Angiogram : This is a non invasive examination of the carotid arteries, it also would give information about past brain damage and any ongoing brain infarcts.
DSA ( Digital Subtraction Angiogram) :It is the gold standard test to detect a narrowing / occlusion of an artery. An angiogram is done if any of the above tests show a significant narrowing or if the above tests are inconclusive. It also helps us localize and size the stenosis so that treatment can be planned.
How can this be treated ?
A carotid stenosis of more than 50 % in symptomatic and more than 70 % in assymptomatic patients needs to be treated. Treatment is also warranted if the stenosis is of a lesser degree but the artery has an irregularity like an ulcerated plaque that would cause an embolic stroke.
Surgery :
Carotid Endarterectomy :
This is an open surgical procedure in which the artery is opened and the narrowing is removed. It is a major surgery and required general anaesthesia.
Carotid Stenting
This is the minimally invasive option to treat carotid stenosis. It is done under local anaesthesia via a small needle prick to the femoral artery in the groin. A fine wire is used to cross the narrowing and an embolic protection device ( a filter ) is placed distal to the narrowing. A balloon angioplasty is done and the lesion is stented using an appropriately sized balloon. The filter catches any dislodged cholesterol particles and prevents them from travelling upstream and blocking blood supply to the brain.
The filter is then carefully removed and an angiogram is done to confirm opening up of the artery.
