This educational exhibit in the form of a pictorial review aims to help the viewer understand the following points in relation borderzone infarctions To classify the different types of borderzone infarction To understand the underlying causative mechanisms of borderzone infarcts To catalogue the imaging features of borderzone infarcts To describe the correct imaging techniques for analysing borderzone infarcts

Borderzone infarctions, often referred to as watershed infarctions, are infarctions occurring at the junction of two different vascular territories. These infarcts have been shown to be associated with haemodynamic impairment but microemboli from inflamed atherosclerotic plaques are postulated to play a role in their pathophysiology1. Borderzone infarcts are far more prevalent in the elderly population and are known to be associated with hypertension, diabetes mellitus, smoking and cerebrovascular disease2. Borderzone infarcts can be divided into Cortical (or external) infarcts and Deep (or internal) infarcts. Borderzone...

Classification of Borderzone Infarcts Borderzone infarctions occur at the junction of two different vascular territories and can be classified as Cortical (external) or Deep (internal). The distribution of Cortical and Deep borderzones is demonstrated on Fig. 1 and Fig. 2 . Cortical infarcts are infarcts of the anterior cerebral artery (ACA) and middle cerebral artery (MCA) junction or the middle cerebral artery and posterior cerebral artery (PCA) junction but can also occur in cases of severe diffuse hypotension. Examples in Case 1; Fig. 3and Fig....

Borderzone infarctions represent almost 10% of all ischaemic strokes and thus radiologists should be aware of their features. These lesions are best appreciated on diffusion weighted and perfusion imaging. Cortical or external borderzone infarctions are typically wedge shaped in appearance and have a relatively benign clinical course. Micro-emboli in conjunction with hypoperfusion insults are postulated to be the most like causative mechanism. Deep or internal borderzone infarcts bear an increased morbidity and confer a higher risk of future stroke. They typically have a string of...

M. Courtney; Dublin/IE - nothing to disclose L. Rice; Dublin/IE - nothing to disclose J. F. Meaney; Dublin/IE - nothing to disclose

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