256层与64层螺旋 CT 动脉造影用于肺动脉栓塞的诊断价值比较

目的：比较256层与64层螺旋CT动脉造影诊断肺动脉栓塞的应用价值。方法回顾性分析接受CT肺动脉造影检查的65例肺动脉栓塞患者资料，所有患者均在发病3 d内在进行256层螺旋CT以及64层CT动脉造影检查。分析并比较两种检查设备对肺动脉栓塞的检出率，并对其图像信噪比、对比噪声比、平均扫描时间及平均造影剂使用剂量进行比较。结果两种设备对肺动脉栓塞的显示率均为100．0％，在噪声、图像信噪比、对比噪声比、扫描长度方面，256层螺旋CT与64层螺旋CT差异无统计学意义（ P＞0．05）。而256层螺旋CT平均造影剂用量为（4．45±1．37）mSv，64层螺旋CT为（5．68±1．06）mSv，差异有统计学意义（t＝2.77，P＜0．05）；平均扫描时间256层螺旋CT为（3．68±1．29）s，64层螺旋CT为（7．61±1．40），差异有统计学意义（ t＝11.33，P＜0．01）。结论256层螺旋CT与64层CT都可以作为临床诊断肺动脉栓塞的有效手段，但256层螺旋CT较64层螺旋CT能显著缩短扫描时间，减少放射性造影剂的用量，具有一定的优势。

Diagnosis value comparison of 256-slice CT and 64-slice CT in pulmonary embolism

Objective To compare the value of 64-slice CT and 256-slice spiral CT in the diagnosis of pul-monary embolism.Methods A retrospective analysis CT pulmonary angiography of pulmonary embolism clinical cases,65 cases were in our hospital ,256-slice CT and 64-slice CT angiography were performed within 3 days of onset . The two kinds of inspection equipment for pulmonary embolism detection rate were analyzed and compared , and its image SNR, in contrast to noise ratio ,average scan time and the average dose of contrast agent used for comparison . Results The two devices display rate of pulmonary embolism was 100.0%,in the noise,image SNR,contrast to noise ratio,scan length,the 256-slice CT and 64-slice CT was no significant difference （P〉0.05）.The average 256-slice CT contrast agent was （4.45 ±1.37） mSv,64-slice CT was （5.68 ±1.06） mSv,there was significant difference between the two （t=2.77,P〈0.05）,an average of 256-slice CT scan time was （3.68 ±1.29）s,64-slice CT was （7.61 ± 1.40）,there was significant difference between the two （t=11.33,P〈0.001）.Conclusion 256-slice CT and 64-slice CT can be used as an effective means of clinical diagnosis of pulmonary embolism ,but compared with 64-slice CT,the 256-slice CT can significantly reduce the scan time ,reduce the amount of radioactive contrast agent ,which has certain advantages .