GE各系列CT机主要性能指标的实验研究

目的：探讨GE各系列CT机主要性能指标的实验研究。方法：CT机质量控制检测是CT机应用中的重要环节，笔者采用Victoreen公司生产的AAPM体模，4000M^ 剂量仪及10cm笔型电离室对GT各系列17例CT机的十项主要性能指标进行了检测。结果：标准算法下10种低档CT的空间分辨率为1．0mm，7种中高档机型可达0．75mm，高分辨率算法下，LightspeedQx/I型可达0．4mm，而8800型却只有0．75mm，所抽检的全部CT其密度分辨率均在0．6％，3．5mm以内，最好的可小于2．5mm。结论：高档CT质量优于普通CT主要表现为，更高的空间分辨率，密度分辨率及轴向分辨率，更快的扫描速度，更多的扫描层数，以及功能更丰富的重要软件。

QA test and study for species of GE manufactured computed tomography scanners

test and study for species of GE manufactured computed tomography scanners Method We used AAPM phantom, 4000M electrometer with 10 cm ion chamber, all manufactured by victoreen company, and test teen QC items of nineteen species of GE manufactured computed tomography scanners. Result In standard scan mode, the high contrast resolution of 10 species of ordinary CT concentrate on 1.0mm, seven high class scanners can reach 0. 75mm; if in high resolution mode the high contrast resolution of lightspeed Qx/I even can be as smaller as 0. 4mm, while 8800 is just 0. 75mm. All of the tested CT's low contrast resolution can be smaller than 3. 5mm, 0. 6% , the best one can be smaller than 2. 5mm, 0. 6%. Conclusion the advantage of high class spiral CT scanners is the better quality of high contrast resolution, low contrast resolution and axial resolution, the faster scan speed, the more scan slices and the powerful reconstructiof software.