摘要
目的探讨低剂量CT扫描结合全模型迭代重组(IMR)技术在周围型肺癌的应用价值,并比较IMR、部分迭代重组算法(HIR)、滤波反投影(FBP)对图像质量的影响。方法搜集经活检确诊为周围型肺癌的患者52例,患者均行低剂量胸部CT(LD-CT)、次低剂量(SLD-CT)及极低剂量(ULD-CT)三次扫描,采用FBP、HIR、IMR分别对三组不同剂量胸部CT扫描的原始数据进行重组,比较FBP、HIR、IMR重组算法在不同剂量下的图像质量及显示周围型肺癌影像特征的优劣。结果ULD-CT组的平均有效辐射剂量为(0.3±0.02)mSv。各等级剂量下,图像客观噪声IMR<HIR<FBP,差异有统计学意义(F=242.8,P<0.05)。ULD-IMR在评价肺癌病灶时,其能力与LD-HIR相似。当患者体质指数(BMI)>25kg/m2时,ULD-IMR图像质量降低,但病灶信噪比(SNR)未受影响(t=0.75,P>0.05)。结论ULD-CT结合IMR剂量与LD-CT相比剂量能降低88%,但不降低图像整体质量,并能良好显示周围型肺癌的影像学征象,且不受患者BMI影响。
Objective To investigate the value of low dose CT combined with iterative model reconstruction ( IMR)technique for evaluation of peripheral lung cancer,and compare the effects of IMR,hybrid iterative reconstruction ( HIR)and filtered back projection ( FBP) techniques on image quality. Methods Fifty-two lung cancer patients confirmed bybiopsy were enrolled. Low dose thoracic CT( LD-CT) followed by 2 reduced-dose protocols( second-low-dose-CT,SLD-CTand ultra-low-dose-CT,ULD-CT) were performed and reconstructed with FBP,HIR,IMR with subsequent image quality a-nalysis and radiologic feature manifesting in peripheral lung cancer comparison. Results The mean effective dose ofULD-CT was ( 0. 3 ±0. 02) mSv. There were significant difference in the objective noise among the three reconstructionsand IMR < HIR < IMR( F =242. 8,P <0. 05) . There was no significant difference in evaluating lung cancer lesions betweenULD-IMR and LD-HIR. Quality deterioration of ULD-IMR when patient's body mass index higher than 25 and none were af-fected by IMR( t =0. 75,P >0. 05) . Conclusion ULD-CT reconstructed with IMR may allow up to 88% radiation dosereduction compared with LD-CT without compromising image quality,and the imaging featurebof peripheral lung cancerwere well demonstrated and were not affected by the patient's body mass index.
作者
梁春意
许乙凯
严承功
肖翔
雷李智
LIANG Chunyi;XU Yikai;YAN Chenggong(Imaging Center,Nanfang Hospital,Southem Medical University,Guangzhou 510515,P. R. China)
出处
《临床放射学杂志》
CSCD
北大核心
2018年第11期1928-1932,共5页
Journal of Clinical Radiology
基金
科技部国家重点研发计划课题(编号:2016YFC-0107104)
广东省省级科研计划项目(编号:2015B010131011)
关键词
迭代重建算法
辐射剂量
体层摄影术
X线计算机
周围型肺癌
Iterative model reconstruction
Tomography,X-raycomputed
Radiation dosage
Peripheral lung cancer
