Objective To evaluate the low-dose dual-source whole-body CT angiography in assessing the arteries of Takayasu’s arteritis (TA).Methods Low-dose whole-body CT angiography(CTA)was performed in 57 consecutive patients with suspected TA. The scanning parameters were performed with tube voltage 80 kV and attenuation-based tube current modulation with a referenced tube current at 300 mAs.The volume CT dose index (CTDIvol)and dose-length product (DLP)were obtained for all scans.Subjec-tive and objective image quality of different arteries were assessed in seven anatomic territories,including intracranial,cervical,tho-racic,abdominal,upper extremity,thigh and shank.In addition,CT findings of whole-body arteries were recorded.Results Forty out of fifty-seven patients with definite diagnosis of TA enrolled in this study.Mean CTDIvol and DLP for all patients were (2.5± 0.9)mGy and (403.7±91.4)mGy·cm,respectively.The scoring order of subjective and objective iamge quality was neck,chest, abdomen,thigh,upper extremity,head and shank.5.9% of intracranial arteries,3.3% of lower extremity arteries and 0.5% of upper extremity arteries were extra detected.Conclusion The extra CT findings of intracranial,lower extremity and upper extremity arter-ies provides a more comprehensive evaluation of whole-body arteries involvement.

Objective To explore the computed tomography angiography(CTA)and clinical features of Takayasu's arteritis(TA)with peripheral artery involvement.Methods In this retrospective study,CTA scan was performed in a total of 184 TA patients.TA patients were divided into two groups:60 patients within peripheral artery involvement(peripheral artery involvement group)and 124 patients without peripheral artery involvement(peripheral artery non-involvement group).The difference in comparison of clini-cal data and CTA findings were analyzed.Results A total of 194 peripheral arteries were involved in 60 patients.The most suscep-tible peripheral artery were axillary artery(52,26.8％),middle cerebral artery(26,13.4％)and femoral artery(22,11.3％).In the peripheral artery involvement group,the most common CTA manifestation was luminal stenosis(141,72.7％).The lumen dilata-tion,lumen stenosis with dilatation and wall calcification were not easy to be observed.The age and duration of disease in peripheral artery involvement group were significantly greater than those in peripheral artery non-involvement group(P＜0.05).The proportion of the peripheral artery involvement group in the active phase was significantly lower than that of the peripheral artery non-involvement group(P＜0.05).The incidence of pain in the limbs in peripheral artery involvement group was significantly higher than that in peripheral artery non-involvement group(P＜0.05).The utilization rate of tocilizumab in the peripheral artery involvement group was significantly higher than that in the peripheral artery non-involvement group(P＜0.05).Conclusion TA involving peripheral arteries is more common in patients with a long course of disease and in the inactive phase.Patients are prone to pain in their limbs.The CT A manifestations of these patients are also special,that is,the involved peripheral arteries are not prone to lumen dilatation and wall calcification.