Cerebral infarction patterns and pathogenesis in patients with internal carotid artery and middle cerebral artery severe stenosis or occlusion： a retrospective cohort study

Objective To investigate the cerebral infarction patterns and pathogenesis in patients with internal carotid artery （1CA） and middle cerebral artery （MCA） severe stenosis （the degree of stenosis 70%-99%） or occlusion in order to provide evidence for the individualized prevention and treatment strategies. Methods Seventy-six patients with acute cerebral infarction who showed the responsible lesions at the corresponding MCA territory on diffusion-weighted imaging （DWI） were analyzed retrospectively. The patients were divided into ICA lesion, MCA lesion and negative result on digital subtraction angiography and CT angiography （NR） goups according to the vascular examinations. Their infarcts were divided into single and multiple infarctions. According to the positions, the former was divided into perforating artery infarct （PAI）, pial infarct （PI）, and border-zone infarct （BZ）. Results The infarct morphologies in the MCA territory were divided into 9 types. The different lesions caused infarct morphologies were different （x2 =34. 000, P =0. 001）. The distribution pattern of multiinfarcts accounted for 73.68% of all patients （56/76）. The distribution pattern of PAI ＋ PI in the ICA lesion group was significantly more than that in the NR group （17/42 vs. 1/16,X2 = 6. 837, P = 0. 009）. There were some correlations between the degree of artery stenosis and the infarct morphology. The severe ICA lesions mostly showed PAI with PI （7/17 vs. 1/16, X2 = 5. 475, P =0. 019）, and the severe MCA lesions mostly showed PAI with BZ （3/8 vs. 1/17, X2=4. 046, P =0. 040）. Conclusions In patients with cerebral infarction of ICA or MCA severe stenosis or occlusion, most of them showed multiinfarct pattern. This suggested that the different mechanisms of stroke onset might be associated with the arterial-arterial embolization or hypoperfusion. Key words: Cerebral infarction;  Carotid stenosis;  Middle cerebral artery;  Intraeranial arteriosclerosis;  Diffusion magnetic resonance imaging, Angiography, digital subtraction;  Magnetic resonance angiography;  Intracranial embolism