基于体模的DSA类CT图像质量研究

Study on the CT-like image quality based on phantom in DSA

目的在数字减影血管造影(DSA)设备上,通过对等效性能的人体仿真体模进行类CT成像,分析DSA中的类CT的图像质量,为DSA设备中类CT图像质量评估提供基础。方法分别在配置相同的西门子dTADSA设备上和飞利浦FD20DSA设备上,利用仿真头颅体模Kyoto Kagaku PBU-60和自制小孔体模进行类CT成像,对采集到的数据进行低对比度、空间均匀性等分析,并进行体模一致性分析。结果这2台设备均能清晰地呈现头颅体模内部血管结构、走行,以及相应的组织结构等信息,对于自制的体模2台设备的低对比度均为0.2%,场均匀性2.624 07 Hu和2.489 75 Hu。结论这2台设备的类CT图像质量指标,包括噪声、低对比度、场均匀性等均符合检测要求,对DSA设备的类CT图像质量控制工作的开展具有一定的实际意义。

Objective To analyze the quality of CT-like image in digital subtraction angiography（DSA） based on the equivalence anthropomorphic phantom,and provide the basis for assessing the quality of CT-like images.Methods The head anthropomorphic phantom（Kyoto Kagaku PBU-60） and the self-made phantom with small-holes were scanned under the same scanning condition.The Siemens dTA and Philips FD20 DSA were used,the low contrast resolution,the spatial uniformity of CT-like image and the concordances of phantoms were analyzed.Results The two DSA devices showed the vascular structure,vascular trend and relative tissue structure information of head anthropomorphic phantom clearly.The low contrast of self-made phantoms were 0.2 %,and the spatial uniformity were 2.624 07 Hu and 2.489 75 Hu.Conclusion It is demonstrated that the index of CT-like image quality indicators from 2 DSA devices（including noise,low-contrast resolution and image uniformity） are conform to the test requirements,it is valuable in CT-like image quality control of DSA.