256层与64层螺旋CT在透析患者上肢CT血管成像中的对比研究

Comparative Study of 256-and 64-slice Computed Tomography Angiography in the Upper Extremity of Hemodialysis Patients

目的比较256层与64层螺旋CT在慢性肾衰竭透析患者上肢CT血管成像(CTA)检查中的效果。资料与方法回顾性分析23例上肢动静脉瘘造瘘患者的CTA图像,10例行64层螺旋CT检查,13例行256层CT检查,两组均采用对比剂追踪触发扫描技术。采用多平面重组、最大密度投影、容积成像、曲面重组等技术对扫描数据进行三维重建,比较两组患者的动脉分支级别、血管边缘、静脉干扰评分及瘘口娴熟情况。结果两组总体上均得到了较好的一致性评价;两组对肩部、上臂血管分支级别的显示能力差异无统计学意义(t=-0.96,P>0.05;t=0.19,P>0.05),对前臂、手部分支级别的显示能力差异有统计学意义(t=-3.17,P<0.01;t=-2.74,P<0.05);256层组对肩部、上臂、前臂血管边缘光滑度的显示质量优于64层组(t=-2.40,P<0.05;t=-2.08,P<0.05;t=-2.53,P<0.05);两组各区域静脉干扰评分及瘘口显示情况差异无统计学意义(P>0.05)。结论相比于64层螺旋CT,256层螺旋CT在血管、内瘘口、流入流出道的细节显示方面效果更佳。

Purpose To compare the image quality of upper extremity computed tomography angiography （CTA） using 256- and 64-slice MSCTA in chronic renal failure hemodialysis patients. Materials and Methods CTA images of 23 hemodialysis patients with AVF in upper extremity were retrospectively analyzed. Ten patients underwent CTA on 64-slice scanner, and 13 patients underwent CTA on 256-slice scanner. Three-dimensional reconstruction including multi-plane reformation （MPR）, maximum intensity projection （MIP）, volume rendering （VR） and curve plane reformation （CPR） were performed, the artery branch level, edge of blood vessel, the ability of excluding the interferer of veins and AVF skill between two groups were compared. Results Totally there was excellent inter-observer agreement in both groups. There was no statistical difference of branch level in the shoulder and the upper arm （t=-0.96, P〉0.05; t=0.19, P〉0.05）, but images of 256- MSCT group demonstrated better images of branch level especially in forearm and hand area （t=-3.17, P〈0.01; t=-2.74, P〈0.05）. In 256-MSCT group, image of vessels also get much more smooth than that of 64-MSCT group （t=-2.40, P〈 0.05 in shoulder; t=- 2.08, P〈0.05 in upper arm; t=-2.53, P〈0.05 in forearm）. However, there was no statistical difference in the ability of excluding the interferer of veins and AVF skill between two groups （P〉 0.05）. Conclusion 256-MSCT can get better images than 64-MSCT in displaying blood vessels, and get much more details of arteriovenous fistula.