Abstract / Summary
Abstract Background This study aimed to perform a comparative analysis of arterial wall conditions in the M1 segment of both the affected and healthy middle cerebral artery (MCA). High-resolution nuclear magnetic resonance imaging (HR-MRI) was used in 52 cases of territorial infarction in the MCA with non-significant stenosis to elucidate the pathogenesis of atherosclerotic ischemic stroke in the non-significant stenosis of MCA. Methods A total of 52 patients with acute ischemic stroke involving the MCA were included. Magnetic resonance angiography (MRA) revealed that the bilateral M1 segment of the MCA (MCA M1) exhibited non-significant stenosis. HR-MRI was performed to determine stenosis rate, plaque stability, burden and location, and vascular remodeling of the culprit MCA M1 on both sides in the same patient. Statistical analysis was performed to explore the correlation with ischemic stroke. Results The comparison was made on both sides of MCA M1 in patients in whom the vessel stenosis rate had no statistical association with acute stroke. Mean (± SD) plaque burden on the lesion side was greater than the contralateral side 14.06 ± 4.616 versus 12.23 ± 4.387, respectively ( t = 2.069, p = 0.041). Plaque on the superior wall of the acute stroke side was greater than that on the contralateral side (χ 2 = 8.694, p = 0.034). The number of unstable plaques on the lesion side was greater than that on the contralateral side (χ 2 = 3.941, p = 0.047). Positive remodeling on the acute ischemic stroke side was greater than that on the contralateral side (χ 2 = 6.848, p = 0.033). Conclusions Plaque load, plaques on the superior wall, unstable plaques, and positive remodeling were closely associated with stroke and the relevant pathogensis of atherosclerotic ischemic stroke in the MCA territory with less than 50% stenosis by HR-MRI. Additionally, the non-significant stenosis in the lumen may be related to positive remodeling of the arterial wall.