Abstract:Objective To analyze carotid plaque nature by color doppler ultrasound and peripheral hemorheological parameters by blood biochemistry in people more than 65 years with acute ischemic stroke (AIS) for assessing severity of stroke. Method A total of 300 AIS patients for first diagnosis from October 2016 to October 2018 were enrolled, including total anterior circulation group (TACI), partial anterior circulation group (PACI), posterior circulation group (POCI) and cavity type group (CA) according to oxfordshire community stroke project (OCSP), and other 50 healthy persons more than 65 years as control group. Then we used doppler ultrasound to detect carotid intima-media thickness (IMT), plaque number, maximum length and nature, whole blood viscosity, plasma viscosity, hematocrit (HCT), erythrocyte sedimentation rate (ESR), plasma fibrinogen (Fib), cholesterol (TC), triglyceride (TG) and blood sugar with automatic biochemical analyzer. Results IMT, number of plaques, maximum length diameter, whole blood viscosity, plasma viscosity, HCT, ESR and Fib in TACI, PACI, POCI and CA groups were all significantly increased compared with control group (P < 0.05). Moderate and severe group were higher than mild group (P < 0.05), and the severe group was higher than the moderate group (P < 0.05). Conclusions The severity of acute ischemic stroke in patients over 65 year old is often related to the formation of carotid plaque and hemorheology.