Watershed infarction

Dissection of the internal carotid and vertebral arteries is a common cause of stroke, particularly in young patients. Although many occur due to trauma, it is estimated that over half occur spontaneously. The mechanism of stroke following arterial dissection is either by artery-to-artery embolism, by thrombosis in situ, or by dissection-induced lumenal stenosis with secondary cerebral hypoperfusion and low-flow watershed infarction. Occasionally, dissection may lead to the formation of a pseudoaneurysm as a source of thrombus formation. Vertebrobasilar dissections that extend intracranially have a higher risk of rupture leading to subarachnoid hemorrhage (SAH). ° ... 

Carotid artery disease is one of the major causes of ischemic stroke. The predominant mechanisms by which it causes stroke are (a) arterial embolism from atherosclerotic plaques (b) hemodynamic changes, leading to watershed infarcts and (c) distal propagation of thrombus originating from acute carotid occlusion. ... 

Pessin MS, Hinton RC, Davis KR et al (1979) Mechanisms of acute carotid stroke. Ann Neurol 6 245-252 Pollanen MS, Deck JH (1989) Directed embolization is an alternate cause of cererbal watershed infarction. Arch Pathol Lab Med 113 1139-1141... 

Torvik A (1984) The pathogenesis of watershed infarcts in the brain. Stroke 15 221-223... 

Hawes DR, Mishkin FS (1972) Brain scans in watershed infarction and laminar cortical necrosis. Radiology 103 131-134... 

Momjian-Mayor I, Baron JC (2005). The pathophysiology of watershed infarction in internal carotid artery disease review of cerebral perfusion studies. Stroke 36 567-577... 

Bladin CF, Chambers BR Clinical features, pathogenesis, and computed tomographic characteristics of internal watershed infarction. Stroke 1993 24 pp. 1925-1932. 

Liu YJ, Chen CY, Chung HW, Huang IJ, Lee CS, Chin SC, Liou M (2003) Neuronal damage after ischemic injury in the middle cerebral arterial territory deep watershed versus territorial infarction at MR perfusion and spectroscopic imaging. Radiology 229 366-374... 

Moreover, analysis of data coming from greater MR series and our own observations reveal no predominance of infarcts in the upper and mid-thoracic region (Mawad et al. 1990 Weidauer et al. 2002). Thus, the concept of a vulnerable watershed zone at T4 is no longer valid in acute spinal cord ischemia. 

A watershed cerebral infarct with subsequent full recovery occurred in a 70-year-old man 8 hours after a hypotensive event following an incremental bolus of 1% lidocaine 10 ml via an established epidural catheter (131). 

Bogousslavsky J, RegU F Unilateral watershed cerebral infarcts. Neurology 1986 36 pp. 373-377. 

Parenchymal enhancement may be visible at 2-3 days, but is consistently present at 6 days and persist for 6-8 weeks [11]. Some infarcts, such as watershed and non-cortical infarcts, may enhance earlier. 

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