Silent brain infarction

Abstract

Background: Silent brain infarction has been described as cerebral infarct and ischemic lesion that are observed on neuroimaging in the absence of any corresponding clinical signs. As availability and quality of imaging techniques has improved in silent brain infarction in many patients who have no previous history of transient ischemic attack or stroke. Silent cerebral infarction is more common in healthy, elderly people, and in patients with dementia, ischemic stroke, diabetes, atrial fibrillation, arterial hypertension and atherosclerosis. Several studies have recently been performed the causes and risk factors for silent brain infarction, and a number of factors have been identified that increase the prevalence of silent brain infarction, most of which are related to stroke. Therefore, some researchers consider silent brain infarction to be a pre-clinical stage of symptomatic stroke. Emphasis is placed on early identification and management of risk factors associated with silent brain infarction, and the need for further research. The majority of silent brain infarctions are located in the subcortical white matter, but 10% are formed in the cerebral cortex. Silent brain infarction is 5 to 10 times more common than overt brain infarction with lacunes of up to 1.5 cm in size, which hypertensive small-vessel disease is thought to be the main cause. Silent brain infarcts are defined lack clinically overt stroke-like symptoms, they are associated with subtle deficits in physical and cognitive function that commonly go unnoticed. Moreover, the presence of silent infarcts more than doubles the risk of subsequent stroke and dementia. Future studies will have to show whether screening and treating high-risk patients can effectively reduce the risk of further infarcts, stroke, and dementia. Summary: In this review, we give an overview of the risk factors, causes, pathogenesis, complications and changes in neuroimaging for silent brain infarction.