Characteristics of MRI and MRA in Patients with Cerebral Watershed Infarction
LI Zhi-yuan;ZHANG Ying;LV Feng-ya;Department of Neurology,Heze Municipal Hospital of Shandong Province;
Objective:To investigate the features of MRI and MRA in detecting different cerebral watershed infarction(CWI) patterns. Methods: Eighty-five CWI patients were retrospectively divided into three types including simple CWI, mixed CWI and multiple CWI. The middle cerebral artery(MCA) and internal carotid artery(ICA) stenosis were evaluated in different CWI patterns. Results: There were 6 patients with simple posterior watershed infarction(PWI), 11 patients with simple internal watershed infarction(IWI), 4 patients with mixed anterior watershed infarction(AWI), 19 patients with mixed PWI, 36 patients with mixed IWI and 19 patients with multiple CWI. Of the 85 patients, the ratio of severe stenosis of MCA was significantly higher than that of ICA(P=0.00). The ratio of severe stenosis of MCA was significantly higher than that of ICA in patients with simple IWI, mixed IWI and multiple CWI(P0.01). The ratio of severe stenosis of MCA in patients with simple IWI, mixed AWI, mixed IWI and multiple CWI was significantly higher than that in the patients with simple PWI and mixed PWI(P0.05). Conclusion: Severe stenosis of MCA is more likely to lead CWI than severe stenosis of ICA, especially in patients with IWI, mixed IWI and multiple CWI. Severe stenosis of MAC has a greater effect on CWI of anterior circulation(ICA system). Hemodynamic abnormality of the far side in patients with severe stenosis of MCA and the declined ability to eliminate micro-embolus may be of important mechanism.