Treatment of intracranial stenosis
What is an intracranial stenosis?
An intracranial stenosis is a narrowing of the arteries supplying blood to the brain, which is generally caused by arteriosclerosis – a systemic disease leading to deposits of blood lipids, connective tissue and lime, known as plaques, on the arterial walls.
The artery becomes narrower and less elastic, until ultimately the blood flow is seriously hindered and the supply of oxygen to the brain area concerned is endangered. The reduction in the blood flow of the brain can either be caused by the narrowing of the artery itself or by the formation of blood clots, which are deposited on the narrow section, then washed away again, leading to an occlusion of another cerebral artery. This harbours a high risk of stroke.
However, a narrowing of the vessels does not represent a danger in every case, as the reduction in blood flow can often be balanced by neighbouring vessels (collateral provision).
What are the consequences and dangers? An intracranial stenosis can result in sensory, sight and speech impairments or paralysis, which either appear temporarily in the form of a so-called transitory ischaemic attack (TIA) or can remain permanently. In particularly severe cases, it can lead to a coma or to death.
What are the risk factors? Unhealthy habits encourage intracranial stenosis but also circumstances that are almost or entirely beyond the control of the individual also play a part. A lifestyle characterised by a high-calorie and high-fat diet, smoking and stress increases the risk, as do high blood pressure, overweight and diabetes. Other factors are age, being male, as well as genetic and constitutional influences.
However, intracranial stenoses can also be caused by injuries or inflammation in the vessel wall.
What are the treatment options? In the case of intracranial stenosis with neurological symptoms, everything should be done to minimise the risk of stroke. As a rule, the first choice is medical therapy, where blood-thinning drugs are administered to prevent the collection of platelets so that sufficient blood flow is preserved. Drugs that lower cholesterol and blood pressure can be used supplementarily. In addition, it is important to follow a healthy and aware lifestyle to minimise risk factors that can be influenced.
If medical therapy alone is insufficient, an intracranial stenosis can be treated by means of a minimally invasive procedure, a percutaneous transluminal angioplasty, or PTA, in which the affected vessel can be enlarged with the aid of a balloon catheter (a thin tube with a small extendable balloon on the tip). In the first instance, a balloon catheter is pushed through the femoral artery into the cerebral artery affected. By stretching the balloon, the narrow section of the artery is widened from the inside.
If necessary, the affected section of the vessel can be given extra support by a stent (a fine mesh tube made of plastic or metal).
For this purpose, there are various stents and processes available for the treatment.
Summary Patients with symptomatic intracranial stenosis face an increased risk of stroke, especially if they have already suffered a stroke. For patients who do not respond adequately to drugs, an invasive procedure can be considered and, in the event of heavily increased risk, sometimes also a stent.
The treatment methods deployed are determined by the treating doctor, taking into consideration the diagnosis and assessing the chances and risks of the type of treatment concerned, in consultation with the patient.
