活动性大动脉炎主动脉CT血管成像的影像特征

Imaging characteristics of CT angiography of the aorta in active Takayasu arteritis

目的探讨活动性大动脉炎主动脉CT血管成像(CTA)的影像特征及临床价值。方法回顾性分析2015年1月至2022年10月新疆维吾尔自治区人民医院风湿免疫科收治的77例大动脉炎(TAK)患者的临床资料、实验室检查结果,分为2组,TAK活动组62例,TAK非活动组15例。其中17例患者进行随访,13例转为非活动性,4例仍为活动性,共94次主动脉CTA影像结果,分为2组,TAK活动组66例次,TAK非活动组28例次。所有患者均行胸腹部CT平扫、主动脉CTA及其后处理检查,其中12例活动性TAK患者行主动脉增强延迟期扫描。采用t检验、Mann-Whitney U检验、χ^(2)检验、Fisher确切概率法及Pearson/Spearman相关性分析,测量、比较2组的影像学特征,分析影像特征与实验室结果、Kerr评分的相关性,评估影像特征的诊断效能,观察治疗前后影像特征变化,分析活动性TAK患者主动脉增强延迟期影像特点。结果TAK活动组与非活动组病程[14(1,29)个月]和[33(8,69)个月,Z=2.70,P=0.007]、身体不适或体质量减轻症状发生率[32.3%(20/62)和20.0%(3/15),χ^(2)=4.08,P=0.043]、ESR增快率[98.4%(61/62)和13.3%(2/15),χ^(2)=64.69,P<0.001]、CRP升高率[69.4%(43/62)和6.7%(1/15),χ^(2)=29.94,P<0.001]比较差异均具有统计学意义,2组血管壁厚度值[(4.2±1.4)mm和(2.4±0.8)mm,t=7.81,P<0.001)]、动脉期管壁CT_(mean)值[(81±8)Hu和(70±13)Hu,t=2.82,P=0.011]、动脉期管壁CT_(max)值[(106±12)Hu和(96±12)Hu,t=2.38,P=0.024]、动脉期管壁相对CT值1(0.20±0.08和0.14±0.04,t=2.56,P=0.016)、动脉期管壁相对CT值2(1.23±0.18和1.06±0.17,t=2.63,P=0.013)、主动脉周围脂肪组织CT_(mean)值[(-31±12)Hu和(-58±20)Hu,t=4.80,P<0.001]、主动脉周围脂肪组织CT_(max)值[-35(-45,-25)Hu和-87(-95,-42)Hu,Z=4.27,P<0.001]、分支周围脂肪组织CT_(mean)值[-28(-33,-14)Hu和-76(-83,-31)Hu,Z=3.37,P=0.001]、分支周围脂肪组织CT_(max)值[-7(-13,-1)Hu和-59(-72,-14)Hu,Z=3.74,P<0.001]、主动脉周围脂肪组织相对CT值(0.26±0.09和0.51±0.19,t=4.47,P<0.001)、分支周围脂肪组织相对CT值(0.17±0.09和0.28±0.18,t=2.35,P=0.025)比较差异也具有统计学意义(管壁厚度值、主动脉周围脂肪组织相对CT值和主动脉周围脂肪组织CT_(mean)值具有较高的诊断效能,临界值分别为3.25 mm、0.455、-55 Hu;AUC分别为0.911、0.887和0.863;约登指数分别为0.687、0.730和0.715;灵敏度、特异度分别为0.758和0.929、0.909和0.821、0.894和0.821。11例活动性TAK患者经治疗后转为非活动性,管壁增厚程度、强化幅度和血管周围脂肪组织密度均有减低。13例活动性TAK患者行主动脉增强延迟扫描,发现主动脉内膜低密度环征在此期显示更清晰,血管壁强化幅度趋于均匀。结论主动脉CTA是定性评估TAK活动性的有效方法。

Objective To explore the imaging characteristics and clinical value of CT angiography(CTA)of the aorta in active arteritis.Methods A retrospective analysis was conducted on the clinical data and laboratory examination results of 77 patients with Takayasu arteritis(TAK)admitted to the Rheumatology and Immunology Department of People′s Hospital of Xinjiang Uygur Autonomous Region from January 2015 to October 2022.They were divided into two groups:62 cases in the TAK active group and 15 cases in the TAK inactive group.Among them,17 patients were followed up,13 cases became inactive,and 4 cases remained active.A total of 94 aortic CTA imaging results were divided into 2 groups,with 66 cases in the TAK active group and 28 cases in the TAK inactive group.All patients underwent plain chest and abdominal CT scans,aortic CTA,and post-processing examinations,with 12 active TAK patients undergoing delayed aortic enhancement scans.The t-test,Mann Whitney U test,χ^(2)Testing,Fisher′s exact probability method and Pearson/Spearman correlation analysis were used for data analysis.The imaging features of the two groups were measured and compared,the correlation between imaging features and laboratory results,Kerr score were investigated.The diagnositic efficacy of imaging features were explored and imaging features before and after treatment were analyzed.Results In the TAK active and inactive groups,course of disease[14(1,29)months vs 33(8,69)months,Z=2.70,P=0.007],Physical malaise or weight loss[32.3%(20/62)vs 20.0%(3/15),χ^(2)=4.08,P=0.043],increased ESR[98.4%(61/62)vs 13.3%(2/15),χ^(2)=64.69,P<0.001],CRP level[69.4%(43/62)vs 6.7%(1/15),χ^(2)=29.94,P<0.001]were statistically significant.The vascular wall thickness of the two groups was significantly different[(4.2±1.4)mm vs(2.4±0.8)mm,t=7.81,P<0.001],CT_(mean) value of the garterial wall[(81±8)Hu vs(70±13)Hu,t=2.82,P=0.011],CT_(max)value of the arterial wall[(106±12)Hu vs(96±12)Hu,t=2.38,P=0.024],relative CT value 1 of the arterial wall(0.20±0.08 vs 0.14±0.04,t=2.56,P=0.016),relative CT value 2 of the arterial wall(1.23±0.18 vs 1.06±0.17,t=2.63,P=0.013),CT_(mean) value of periaortic adipose tissue[(-31±12)Hu vs(-58±20)Hu,t=4.80,P<0.001)],CT_(max)value of periaortic adipose tissue[-35(-45,-25)Hu vs-87(-95,-42)Hu,Z=4.27,P<0.001],CT_(mean) value of adipose tissue around branches[-28(-33,-14)Hu vs-76(-83,-31)Hu,Z=3.37,P=0.001],CT_(max)value of adipose tissue around branches[-7(-13,-1)Hu vs-59(-72,-14)Hu,Z=3.74,P<0.001],relative CT values of adipose tissue around the aorta(0.26±0.09 vs 0.51±0.19,t=4.47,P<0.001)],relative CT values of adipose tissue around branches(0.17±0.09 vs 0.28±0.18,t=2.35,P=0.025)were significant different.The wall thickness value,relative CT value of periaortic adipose tissue,and CT_(mean) value of periaortic adipose tissue had high diagnostic efficacy,with cut-off values of 3.25 mm,0.455,and-55 Hu,respectively.The AUCs were 0.911,0.887,and 0.863,respectively.The Youden index was 0.687,0.730,and 0.715,respectively.The sensitivity and specificity were 0.758 and 0.929,0.909 and 0.821,0.894 and 0.821,respectively.After treatment,11 active TAK patients became inactive,with reduced wall thickening,enhancement,and density of perivascular adipose tissue.Thirteen patients with active TAK underwent delayed aortic enhancement scanning,and it was found that the low-density loop sign of the aortic intima was more clearly displayed during this period,and the enhancement amplitude of the vascular wall tended to be uniform.Conclusion Aortic CTA is an effective method for qualitative evaluation of TAK activity.