Objective To investigate the correlation between semi-quantitative contrast-enhanced ultrasonographyin evaluating neovascularization in carotid plaques and circulating blood neutrophil/lymphocyte ratio（NLR）

and explore therole of NLR in plaque neovascularization and plaque vulnerability influences.MethodsA total of 132 subjects who underwentcarotid plaque contrast ultrasonography were selected and grouped according to the classification of neovascularization in theplaque by semi-quantitative contrast-enhanced ultrasound:60 cases in grades 1～2（group A）and 44 cases in grade 3（group B）and 28 cases in grade 4（group C）.Meanwhile

the number of circulating blood white blood cells（WBC）

neutral cells（NE）

andlymphocytes（LY）and neutrophil/lymphocyte ratio（NLR）were obtained from the three groups.Spearman correlation was used toanalyze the correlation between plaque contrast-enhanced ultrasound classification and leukocyte subtypes in circulating blood.Logistic regression was used to further analyze the independent risk factors that affected neovascularization within the plaque.Results WBC and NE increased sequentially in groups A

B

and C

while LY decreased in order

and the differences werestatistically significan（tall P<0.01）;NLR was the lowest in group A and the highest in group C

the differences were statisticallysignificant（P<0.01）.The neovascularization grade of carotid plaque was positively correlated with WBC

NE and NLR in bloodcirculation（r=0.30

0.59 and 0.77

all P<0.01）

but negatively correlated with LY（r=-0.50

P<0.01）.The proportion of patientswith cerebral infarction among the three groups was the highest in group C

and the difference was statistically significant（P<0.05）.Logistic regression analysis indicated that NLR was an independent risk factor for neovascularization in the plaque.For every 1.08 increase of NLR in blood circulation

the neovascularization grading increased by one level.Conclusion NLR incirculating blood is closely related to neovascularization in the plaque and is an independent risk factor.For every 1.08 increasein NLR

the neovascularization grading increases by one level.