Lacunar stroke

From Wikipedia, the free encyclopedia

Please help improve this article or section by expanding it. Further information might be found on the talk page or at requests for expansion. (May 2007)

Lacunar stroke occurs when one of the small arteries (diameter: 0.2 － 15mm) that provides blood to the brain's deep structures is blocked and injures deeper structures underneath the cortex. It may be referred to as a Lacunar Infarct (LACI). A patient who presents with the clinical symptoms of a lacunar stroke, but who has not yet had diagnostic imaging performed may be described as suffering from Lacunar Stroke Syndrome (LACS)

[edit] Pathophysiology

Lacunes are caused by occlusion of a single deep penetrating artery. The deep penetrating arteries are small nonbranching end arteries (usually smaller than 500 micrometers in diameter), which arise directly from much larger arteries (eg, the middle cerebral artery, anterior choroidal artery, anterior cerebral artery, posterior cerebral artery, posterior communicating artery, cerebellar arteries, basilar artery). Their small size and proximal position predisposes them to the development of microatheroma and lipohyalinosis.

At the beginning, lipohyalinosis was thought to be the main small vessel pathology of lacunes; however, microatheroma now is thought to be the most common mechanism of arterial occlusion (or stenosis). Occasionally, atheroma in the parent artery blocks the orifice of the penetrating artery (luminal atheroma), or atheroma involves the origin of the penetrating artery (junctional atheroma).

A hemodynamic (hypoperfusion) mechanism is suggested when there is a stenosis (and not occlusion) of the penetrating artery. When no evidence of small vessel disease is found on histologic examination, an embolic cause is assumed, either artery-to-artery embolism or cardioembolism. In one recent series, 25% of patients with clinical radiologically defined lacunes had a potential cardiac cause for their strokes.

[edit] The Clinical Picture

It is estimated that lacunar infarcts account for 25% of all strokes that are due to ischemia (so-called "ischemic strokes").

Patients tend to present with a pure motor, pure sensory or sensorimotor dysfunction or 'ataxic hemiparesis'. They will often recover well.

[edit] Related conditions

If there is enough white matter disease from lacunar pathology, one can see a subcortical dementia such as Binswanger disease.

[edit] Synonymous Terms

lacunar infarcts

[edit] See also

Stroke

[edit] External links

• 282066961 at GPnotebook