摘要
目的：评价采用iDose迭代重建技术（IR）对低管电流胸部CT增强扫描图像噪声及其图像质量的影响。方法：选取62例行胸部CT增强扫描的门诊或住院病人，随机分为常规剂量（120kVp，200mAs）和低剂量（120kVp，50mAs）组。对常规剂量组采用FBP进行重建（A组），低剂量组则分别采用FBP（B组）；和iDose迭代重建技术（C组）进行重建。记录各组的噪声、信噪比（SNR）、对比度噪声比（CNR）和有效剂量（ED），按1～3分评价总体图像质量，并对3组结果进行比较。结果：低剂量组的有效剂量（ED）较常规剂量组降低74．71％。C组图像噪声较B组小（P〈0．001），较B组降低33．39％；且C组的噪声、SNR、CNR与A组差别不大（P〉0．05），但与B组的噪声、SNR、CNR具有明显统计学意义。C组总体图像质量与A组无差异（P〉0．05）；B组总体图像质量与A、C两组均有显著性差异（P〈0．05）。结果表明，在辐射剂量相同的情况下，迭代重建技术较FBP可以明显提高图像质量。结论：和传统滤波反投影FBPkL较，运用迭代重建技术可以明显降低噪声，从而在低管电流胸部CT增强扫描中获得满足诊断要求的图像。
Purpose： To evaluate the image quality of an iterative reconstruction algorithm （iDose） in contrast-enhanced chest CT with low tube current settings in comparison with standard-dose filtered back projection （FBP） CT. Methods： Sixty-two patients were referred for a contrast-enhanced chest CT. The patients were randomly assigned into two protocols： A （120KV/200mAs） and B （120KV/50mAs）. Standard convolution FBP was used to reconstruct protocols A （group A） and B （group B） image sets, and iterative reconstructions （iDose） was used to reconstruct protocol B （group C） image sets . The mean image noise, signal-to-noise ratio （SNR）, contrast-to-noise ratio （CNR） and effective dose （ED） of the image sets with each protocol were assessed. Image quality were graded （scale： 1-3） and compared among 3 groups. Re- sults： Radiation dose was 74.71% less for the low dose protocol. Noise was significantly lower in low dose images reconstructed with iDose （Group C） than that in images reconstructed with FBP （Group B）. There was no statistical significant difference in subjective image quality scores between Group C and A P〉0.05）. Conclusions： In contrast-enhanced chest CT examinations, images reconstructed with iterative reconstruction had better image quality at a lower radiation dose than images acquired with a conventional FBP reconstruction algorithm.
出处
《中国医学计算机成像杂志》
CSCD
北大核心
2014年第2期191-194,共4页
Chinese Computed Medical Imaging
基金
上海市科委科研计划重点项目(NO.13411950100)
国家自然基金(NO.81071155
NO.81171333
NO.81230030)~~
关键词
放射剂量
体层摄影术
X线计算机
胸部
迭代重建
Radiation dose
Tomography, X-ray computed
Chest
Iterative reconstruction
