|
|
|
| Study of the effect of water phantom setting patterns on CT |
| ZHU Weijie1, FENG Zechen1, HAO Kun2, XU Hui3 |
1. Beijing Center for Disease Prevention and Control, Beijing 100013 China;
2. Peking Union MedicalCollege Hospital;
3. National Institute for Radiological Protection, China CDC |
|
|
|
|
Abstract Objective To compare the effects of two types of phantom setting methods (suspension and place-on-couch) on the CT value (water), noise and uniformity of performance test results, and to find out which mehtod is more reasonable.Methods According to the method in GB 17589-2011, two kinds of phantom place patterns were tested:suspend the CT-WV17 phantom on-the phantom box or directly place the CT-WV17 on couch. With the same scanning parameters, the phantom was scanned for 5 times at each setting patterns, and the CT value (water), noise and uniformity on the images were measured.Results For the CT value (water), the results were averaged to be (0.39±1.49) HU and (1.00±1.83) HU for different phantom setting patterns, respectively, and the difference was significant (t=-2.55, P=0.022). In noise test, the results were averaged to be (0.23±0.06) and (0.25±0.08) for the two methods, respectively, and the difference was also significant (t=-3.38,P=0.004). In the unifomity test, the averaged results were (0.47±0.66) HU and (-0.06±1.82) HU for the two setting patterns, respectively, the significant difference (t=4.25,P=0.001) was also observed.Conclusion Carbon fiber couch has a potential impact on CT value (water), noise and uniformity. When testing CT value (water), noise and uniformity, the phantom-suspension should be used.
|
|
Received: 27 March 2018
|
|
|
|
|
|
[1] Szczykutowicz T, Duplissis A, Miller D.Image Noise Uniformity and CT Number Changes as a Function of Positioning[J].Medical Physics, 2016, 43(6):3772.
[2] 中华人民共和国卫生部. GB 17589-2011 X射线计算机断层摄影装置质量保证检测规范[S].北京:中国标准出版社,2012.
[3] Liu RR, Prado K, Wu R, et al.On-Couch Procedure and Phantom in Radiation Oncology[J].Medical Physics,2007,34(6):2350-2350.
[4] Ali I, Ahmad S, Alsbou N, et al. Correction of image artifacts from treatment couch in cone-beam CT from kV on-board imaging[J]. J Xray Sci Technol, 2011, 19(3):321-332.
[5] 时飞跃,秦伟,陈飞,等.碳纤维平板对水的CT值影响的研究[J].中国医疗设备,2013,28(3):69-70,157.
[6] 张国前,张书旭,余辉,等.放疗定位扫描条件对CT值的影响[J].中国医疗设备,2015,30(3):13-16.
[7] 陈疆红,贺文,赵丽琴,等.适应性统计迭代重建技术降低胸部低剂量CT图像噪声的效果[J].中国医学影像技术,2011,27(12):2398-2402. |
|
|
|
