第二代双源CT肺动脉造影扫描方案优化选择  

Optimization of scan protocol in pulmonary angiography of second generation dual source computed tomography

作　　者：陈彬[1] 张文明[1] 胡吉波[1] 胡红杰[1] 

机构地区：[1]浙江大学医学院附属邵逸夫医院放射科,杭州310016

出　　处：《中华医学杂志》2012年第31期2186-2190,共5页National Medical Journal of China

基　　金：浙江省科技厅科技计划（2010C33106）;浙江省教育厅项目（Y201017413）

摘　　要：目的探讨第2代双源CT行CTPA的扫描方案时其增强对比剂合理使用剂量。方法选择2011年1—6月，浙江大学医学院附属邵逸夫医院120例临床疑似肺动脉栓塞患者，行第2代双源CT．CTPA检查。患者随机分为4组，采用小剂量团注测试，双管注射对比剂及生理盐水，各组注射方案为：A组：35ml对比剂＋55ml生理盐水，B组：40rnJ对比剂＋50ml生理盐水，c组：45ml对比剂＋45rnl生理盐水，D组：50ml对比剂＋40ml生理盐水。两位影像医师测量统计各目标血管增强CT值、并对图像质量及碘图伪影评分。结果A组各段肺动脉增强CT值高于200HU的比率（80％一90％）低于B、c、D3组（93％一100％）（均P〈0．05），B、C、D3组问差异无统计学意义（P〉0．05）；A组图像质量评分4．33明显低于B、C、D3组（〉4．8）（均P〈0．05），B、c、D3组差异无统计学意义（P〉0．05）；A组碘图伪影评分明显高于其他3组（P〈0．05），即伪影最少，D组明显低于其他3组（P〈0．05），即碘图伪影最多，B、C组碘图伪影评分差异无统计学意义（P=0．091）。结论B、C组（40ml对比剂＋50ml生理盐水、45ml对比剂＋45ml生理盐水）方案图像质量好，碘图伪影少，两组差异无统计学意义。本着尽量减少对比剂使用剂量的原则，B组扫描方案较C组方案更值得临床借鉴使用。Objective To explore the scan protocol of second generation dual source computed tomography （CT） for CT pulmonary angiogram （CTPA） in patients with suspected pulmonary embolism and determine the proper volume of contrast medium. Methods A total of 120 patients undergoing CTPA were recruited. All examinations were performed on a second generation dual source CT. The scan delay was determined with the test bolus technique. Four contrast volume protocols were designed, namely groups A, B, C and D respectively （n =30 each）. For CTPA scan of groups A, B, C and D, 35, 40, 45 and 50 ml contrast medium were injected at an injection rate of 4 ml/s, followed by a saline chaser of 55, 50, 45 and 40 ml respectively. Attenuation profiles of different vascular segments （subclavian vein, vena cava, left atrium, pulmonary trunk, S1 artery, $10 artery） were measured to evaluate the timing techniques. The image quality and artifact of iodine map were analyzed by two radiologists for comparisons. Results The percentage of pulmonary arteries exceeding optimal attenuation （ 〉 200 HU） showed that groups of B, C and D were higher than group A （93% - 100% vs 80% -90% ）. The image quality of group A was lower than the others （ P 〈 0. 05） while the other groups showed no significant difference. The artifacts of iodine map of group A were much fewer than the others （P 〈 0. 05 ） and group D was much more than the other groups （P〈0.05）. Groups B and C had a score of 4. 13 and 3.67 respectively without significant difference （P=0.091）. Conclusion With the aids of test bolus technique and proper injection protocol （40 ml contrast medium followed by 50 ml saline）, the high quality image and low volume of iodine can be realized with second generation dual source CT for CTPA.

关 键 词：体层摄影术 X线计算机 肺栓塞 造影剂 

分 类 号：R816.2[医药卫生—放射医学]