双源CT在儿童颞骨检查中低剂量扫描条件的研究  

The optimized low dose scanning protocol in children's temporal bone examination with dual-source CT

作　　者：张广文[1] 张劲松[1] 李剑[1] 刘丛伟[1] 吴志斌[1] 刘豹[1] 王栋[1] 

机构地区：[1]第四军医大学附属西京医院放射科,西安710032

出　　处：《放射学实践》2016年第2期171-174,共4页Radiologic Practice

摘　　要：目的:探索儿童颞骨双源CT扫描中,低管电压、低管电流及正弦确定迭代重建(SAFIRE)技术降低辐射量的能力及对图像质量的影响。方法:将120例行颞骨高分辨率CT(HRCT)检查的儿童,按就诊时间随机分为常规剂量组A组(120kV,180mAs,滤波反投影重建)及低剂量组B组(120kV,110mAs,SAFIRE技术)、C组(100kV,110mAs,SAFIRE技术)、D组(100kV,80mAs,SAFIRE技术),每组30例。统计比较4组的平均CT值、噪声、对比噪声比(CNR)、信噪比(SNR)、剂量长度乘积(DLP)、有效剂量(ED)、图像质量评分,P<0.05为差异有统计学意义。结果:经组间方差分析,4组平均CT值无明显统计学差异(F=1.02,P>0.05);噪声、CNR、SNR、DLP、ED和图像质量评分差异均具有统计学意义(F=43.57、55.60、16.50、406.15、50.80、154.07,P均<0.05)。与A组相比,B、C、D组噪声分别降低36.9%、26.0%、16.3%;DLP分别降低39.5%、60.9%、71.6%;ED分别降低25.5%、50.6%、65.6%。结论:应用低管电压(100kV)、低管电流(80mAs)及迭代重建技术进行儿童颞骨HRCT扫描,在满足临床诊断需求的图像质量前提下,可有效降低辐射量。Objective：To explore the use of low tube voltage,low tube current and sinogram affirmed iterative recon- struction （SAFIRE） technique in reducing the radiation dose on scanning objects and its influence on image quality in chil- dren＇s temporal bone examination with dual source CT. Methods：For high resolution CT scan of temporal bone,120 cases of children patients were divided according to date of clinical examination randomly, into four groups： the conventional dose group,Group A （120kV, 180mAs, filtered back projection reconstruction technique）, low dose group, Group B （120kV, 110mAs, SAFIRE technique） ,Group C （100kV, 110mAs, SAFIRE technique） ,and Group D （100kV, 80mAs, SAFIRE tech- nique） ,with 30 cases in each group. Statistical analysis and comparison were made of the average CT value, noise, CNR, SNR, CTDIvol, DLP, ED and subjective evaluation score. Results：By the analysis of inter-group variance, there were no sta- tistical differences in mean CT value among the four groups （F= 1.02, P〉 0.05）, while differences in noise, CNR, SNR, DLP, ED and subjective evaluation score were statistically significant （F=43. 57,55. 60,16. 50,406.15,50. 80,154. 07, respectively; P〈0.05）. Compared with group A, noise reduction in group B, C and D were 6.9 %, 26 %, 16.3 %, respectively. Reduction of CTDIvol,DLP, ED in group B, C and D were 38. 7%, 61. 3%, 71. 9% ; 39. 5%, 60. 9%, 71. 6% ; 25. 5%, 50.6 %, 65.6% ;respectively. Conclusion： The use of low tube voltage, low tube current and SAFIRE technique for HRCT temporal bone scan can effectively reduce the radiation dose in patients on the basis of meeting the needs of image quality for clinical diagnosis.

关 键 词：儿童 颞骨 体层摄影术 X线计算机 迭代重建 辐射剂量 

分 类 号：R816.92[医药卫生—放射医学]