Objective To explore the evaluation value of thyroid function indicators[thyroid stimulating hormone(TSH),free thyroxine(FT4),free triiodothyronine(FT3)]combined with transcranial Doppler ultrasound(TCD)and carotid ultrasound in the assessment of vascular stenosis in atherosclerotic cerebral infarction(ASCI),providing a reference for clinical targeted treatment.Methods A total of 182 patients with ASCI admitted to Handan Frist Hospital from October 2021 to September 2023 were selected and all of them underwent TCD,carotid artery ultrasound and thyroid function examination.Digital subtraction angiography was used as the gold standard to analyze the evaluation effect of TCD and carotid artery ultrasound combined with TSH,FT4 and FT3 in vascular stenosis of ASCI.Results Among the 182 patients with ASCI,DSA confirmed 64 cases(35.16％)with mild internal carotid artery stenosis,69 cases(37.91％)with moderate stenosis,29 cases(15.93％)with severe stenosis,and 20 cases(10.99％)with complete occlusion.There was no statistically significant difference in clinical data among groups with different degrees of vascular stenosis(P＞0.05).The peak systolic velocity(PSV)and end-diastolic volume(EDV)of the internal carotid artery in different groups with different degrees of vascular stenosis showed an increasing trend with the severity of vascular stenosis,while the pulse index(PI),resistance index(RI),and diameter(D)showed a decreasing trend(P＜0.05).In different groups with different degrees of vascular stenosis,TSH and FT4 levels increased with the severity of stenosis,while FT3 levels decreased(P＜0.05).TSH and FT4 were positively correlated with the degree of vascular stenosis,while FT3 was negatively correlated(P＜0.05).TSH and FT4 were positively correlated with PSV and EDV,and negatively correlated with RI,PI,and D.FT3 was positively correlated with RI,PI,and D,and negatively correlated with PSV and EDV(P＜0.05).The combined evaluation of RI,PI,D,PSV,EDV,TSH,FT4,and FT3 yielded the highest area under the curve(AUC)value of 0.941 for assessing ASCI vascular stenosis(P＜0.05).Conclusion The combination of TCD,carotid ultrasound,and thyroid function tests have high value in the assessment of ASCI vascular stenosis.The joint evaluation of RI,PI,D,PSV,EDV,TSH,FT4 and FT3 is beneficial for diagnosing different degrees of vascular stenosis,providing a reference for clinical treatment.r clinical treatment.