64层双源CT管电流自动调节技术配合降噪处理在胸部低剂量CT中的应用价值

Application value of automatic tube current modulation with noise reduction in low dose CT with 64-slices spiral dual-source CT

目的：探讨64层双源螺旋CT自动管电流调节技术配合降噪处理在胸部低剂量CT中的应用价值。方法选取2014年3~7月参加我院胸部CT检查的健康人群受检者200名，抽取其中100名，接受低剂量螺旋CT检查，作为A组；另100名接受常规CT平扫检查，作为B组，由两名胸部专业放射科医师采用双盲法对肺尖、中肺、下肺图像进行图像质量评分（IQS），测量图像标准差（SD）值，记录容积CT剂量指数（CTDIvol），并进行统计学分析。结果肺尖、中肺、下肺的图像标准差SD值，A组分别是（34.34±2.17）、（30.63±0.74）、（30.74±1.21）；B组分别是（36.82±2.51）、（34.15±1.98）、（31.69±1.93）。肺尖，中肺，下肺的图像质量评分的IQS值，A组分别是（1.83±0.36）、（1.59±0.38）、（1.64±0.34）；B组分别是（2.31±0.47）、（1.68±0.42）、（1.73±0.48）。在肺尖，A组的SD值和IQS低于B组（P〈0.05）。结论在低剂量肺部CT检查中应用管电流自动控制技术并配合降噪处理，将使辐射剂量分布趋于合理化，更有利于观察肺尖的结构，提高该部位疾病的检出率。

Objective To evaluate the application value of automatic tube current modulation （ATCM） in low dose chest scaning with 64-slices spiral dual-resource CT. Methods Randomly selected healthy people to participate in our hospital from March 2014 to July 2014 in subjects with chest CT examination were 200, 100,received low dose spiral CT examination,as the A group;the other 100 underwent routine CT plain scan,as the B group,All CT images were analyzed by two radiologists with double blind method.Image quality scores （IQS）of lung apex,middle lung and lower lung were made,the image standard deviation（SD）was measured,and the CTDIvol was also recorded,and the statistical analysis was performed. Results SD values in lung apex,middle and lower lungs was （34.34±2.17）,（30.63±0.74）,（30.74±1.21）in group A,and （36.82±2.51）、（34.15±1.98）,（31.69±1.93 ）in group B,as well as the corresponding IQS of these three sites were（1.83±0.36）,（1.59±0.38）,（1.64±0.34）in group A,and（2.31±0.47）,（1.68±0.42）,（1.73±0.48）in group B,respectively. SD value and IQS of group A were lower than those of group B in lung apex（P〈0.05）. Conclu-sion The application of ATCM in low dose chest CT scanning plus noise suppression can provide more homogeneous images with better image quality.