摘要
目的:评价Flash大螺距模式下智能最佳管电压调节结合原始数据迭代重建技术在CT胸主动脉成像中的图像质量和辐射剂量。方法:按扫描方式将患者分成A,B两组。A组扫描参数采用大螺距模式,智能最佳kVp技术扫描,图像重建方式为迭代重建;B组扫描参数采用常规螺距,120kVp管电压,图像重建方式为滤波反投影法,比较两组客观图像质量及辐射剂量。结果:两组患者年龄、性别均无明显差别。客观图像质量A组明显好于B组。胸主动脉3个位置CT值无统计学差异,但A组的SNR、CNR均明显高于B组,背景噪声A组低于B组。两组主观图像质量评分均无统计学差异。两位医生的一致性分别为0.737、0.617和0.705。A组有效剂量要明显低于B组,降低了30%。结论:大螺距智能最佳管电压调节结合原始数据迭代重建技术CT胸主动脉成像不但有效的降低了辐射剂量,还同时提高了图像质量。
Objective:To investigate the image quality and the radiation dose of high pitch,automated attenuation-based tube voltage selection and iterative reconstruction technique for CT angiography of the thoracic aorta.Methods:The patients were divided into two groups according to the scan parameters.Groups A:high pitch (pitch= 3.0),automated attenuation-based tube voltage selection and image reconstruction methods with SAFIRE (sinogram affirmed iterative reconstruction).Group B:conventional pitch (pitch= 1.2),120kV tube voltage,image reconstruction methods using the FBP (Filtered Back Projection).Objective and subjective image quality and radiation dose were evaluated and compared.Results:There was no significant difference between two groups in the age and gender distribution.The objective image quality of group A was better than that of group B.The CT values of three positions of thoracic aorta had no significant difference. The SNR,CNR of group A were significantly higher than these of group B and the background noise of group A lower than that of group B.Two groups of subjective image quality scores had no significant difference.The Kappa values of two doctors were 0.737,0.617,0.705,respectively.The radiation dose of group A was lower than that of group B,which decreased by approximately 30%.Conclusion:High pitch,automated attenuation-based tube voltage selection and iterative reconstruction technique for CT angiography of the thoracic aorta not only effectively reduces the radiation dose,but also maintains the diagnostic image quality.
出处
《放射学实践》
2014年第6期597-600,共4页
Radiologic Practice
关键词
诊断技术
心血管
主动脉
胸
体层摄影术
X线计算机
图像处理
计算机辅助
Diagnostic techniques,cardiovascular
Aorta,thoracic
Tomography,X-ray computed
Image process-ing,computer-assisted