Also called ischemic stroke, a cerebral infarction occurs as a result of disrupted blood flow to the brain due to problems with the blood vessels that supply it. A lack of adequate blood supply to brain cells deprives them of oxygen and vital nutrients which can cause parts of the brain to die off.
The reduced blood supply to the brain is caused by atherosclerosis which gives rise to the formation of a fatty plaque in the blood vessel called an atheroma. This fatty deposit can cause a thrombus or blood clot in an artery that supplies the brain or in another part of the body, in which case the clot is called an embolism. A piece of this clot may break away and travel to the blood vessels in the brain where it lodges and forms a cerebral embolism.
An embolism may also be caused by atrial fibrillation which can cause a clot to form in the heart and then dislodge and travel to vessels in the brain via the blood stream.
People with high blood cholesterol and high blood pressure are at an increased risk of cerebral infarction. Other risk factors include smoking, obesity, a family history of heart disease, diabetes and excessive alcohol consumption.
Classification of cerebral infarction
The Oxford Community Stroke Project classification is a system used to categorize stroke into four categoreis based on the extent of the initial symptoms.
The four categories include:
- Total anterior circulation infarct (TACI)
- Partial anterior circulation infarct (PACI)
- Lacunar infarct (LACI)
- Posterior circulation infarct (POCI)
These categories can be used to predict the cause of the stroke, the degree of damage, the brain areas affected and the likely patient outcome.
Another system called TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification, categorises the stroke according to clinical symptoms and other investigations. The stroke is then classed as due to one of the following:
- Embolism or thrombosis due to atherosclerosis of a large artery
- Embolism originating in the heart
- Occlusion of a small blood vessel
- Other identified cause
- Other undetermined cause
Reviewed by Sally Robertson, BSc