引导螺旋断层放疗用兆伏CT图像质量定量分析

doi:10.19723/j.issn.1671-167X.2019.03.022

北京大学学报（医学版） ›› 2019, Vol. 51 ›› Issue (3): 525-529. doi: 10.19723/j.issn.1671-167X.2019.03.022

引导螺旋断层放疗用兆伏CT图像质量定量分析

黄宇亮¹,李晨光¹,毛凯²,武建安²,戴甜甜²,韩媛媛²,吴昊¹,王海洋¹,张艺宝^1△()

收稿日期:2019-03-14 出版日期:2019-06-18 发布日期:2019-06-26
作者简介:张艺宝,高级工程师,硕士研究生导师,北京大学肿瘤医院放疗教研室副主任。2013年毕业于北京大学物理学院,获工学博士,并获国家奖学金、北京市优秀毕业生等;2010—2011年受国家留学基金委派遣赴美国耶鲁大学联合培养16个月;2008年获北京大学医学部和信息科学技术学院双学士、北京市优秀学生干部等。已发表SCI论文22篇,国家级核心期刊论文30余篇。主持国家自然科学基金、北京市自然科学基金、首都卫生发展科研专项基金、北京市医院管理局“青苗”人才专项基金、北京大学医学部青年培育基金各一项。现担任中国生物医学工程学会医学物理分会青年委员、中华医学会影像技术分会质量控制专业委员会委员、北京医学会放射肿瘤治疗学分会物理学组委员、北京医学会放射肿瘤专业委员会青年委员等。同时担任《中国医学物理学杂志》编委,Journal of Cancer、Physica Medica、Journal of Applied Clinical Medical Physics、《中华放射医学与防护杂志》等SCI和核心期刊评审人。专业为放射治疗物理学,研究方向主要包括:影像引导放疗中成像剂量的个体化评估、风险管理和参数优化;基于图像的在体剂量监测、三维重建和自适应放疗;基于人工智能的放疗计划自动设计和质量控制等。
基金资助:
首都卫生发展科研专项(首发2018-4-1027)、北京市自然科学基金(7172048)、国家自然科学基金(11505012,11505300)、北大医学青年科技创新培育基金(BMU2017PY028)-中央高校基本科研业务费、四川省科技厅项目(2018HH0099)、北京市属医院科研培育项目(PX2019042,PX2016060)、北京市医院管理局“青苗”计划专项经费(QML20171104)

Quantitative evaluation of image quality of megavoltage computed tomography for guiding helical tomotherapy

Yu-liang HUANG¹,Chen-guang LI¹,Kai MAO²,Jian-an WU²,Tian-tian DAI²,Yuan-yuan HAN²,Hao WU¹,Hai-yang WANG¹,Yi-bao ZHANG^1△()

Received:2019-03-14 Online:2019-06-18 Published:2019-06-26
Supported by:
Supported by the Capital’s Funds for Health Improvement and Research (2018-4-1027), Beijing Natural Science Foundation (7172048), the National Natural Science Foundation of China (11505012, 11505300), the Fundamental Research Funds for the Central Universities: Peking University Medicine Fund of Fostering Young Scholars’ Scientific & Technological Innovation (BMU2017PY028), Sichuan Science and Technology Program (2018HH0099), Beijing Municipal Administration of Hospitals Incubating Program (PX2019042, PX2016060), and Beijing Municipal Administration of Hospitals’ Youth Programme (QML20171104)

摘要/Abstract

摘要： 目的定量分析螺旋断层放疗系统3种兆伏CT扫描模式获取的2套模体图像质量,探索和验证螺旋断层放疗系统兆伏CT图像的半自动质控方法。方法分别使用螺旋断层放疗系统上螺距为4 mm、8 mm、12 mm/圈的Fine、Normal和Coarse模式,获取CatPhan504和Cheese模体的兆伏CT图像。基于Pylinac、Matlab和Eclipse软件自动分析对比3种模式下图像的空间分辨率、图像噪声和低对比度分辨率。结果对CatPhan504空间分辨率模块的分析显示,Coarse模式的前3个线对(间距分别为0.500 cm、0.250 cm和0.167 cm)清晰但从线对4(间距为0.125 cm)开始发生了明显混叠,而Normal和Fine的前4个线对均可清晰观测。Coarse、Normal和Fine模式下Cheese模体的总体不均匀度分别为0.157 7、0.136 8和0.122 9。3种成像模式所得Cheese图像的低对比度分辨率相近,且随着构造材料与局部背景CT平均差值的增大,插件的可观测性呈近乎线性增长。结论 3种成像模式在3个图像质量评估指标上并未呈现一致优劣性。临床上螺旋断层放疗系统成像模式的选择可基于图像观测的需求,参考本研究的评估结果,从而做出决策,相关图像质量评估工作也可参考本研究的方法,定期进行相关质控测试。

关键词: 螺旋断层放疗, 兆伏CT, 图像质量, 质量控制

Abstract: Objective: To quantitatively analyze image quality of two sets of phantom (CatPhan504 and Cheese) Megavoltage computed tomography (MVCT) images acquired by Helical Tomotherapy with three scanning modes (Fine, Normal and Coarse), and to explore and validate a semi-automatic quality assurance procedure for MVCT images of Helical Tomotherapy.Methods: On Helical Tomotherapy, CatPan504 and Cheese phantoms were scanned with three pitch levels (Fine, Normal, Coarse: 4 mm, 8 mm, 12 mm/circle) respectively. Pylinac, Matlab and Eclipse were used to calculate and compare spatial resolution, noise level and low contrast resolution of images obtained under three scanning modes respectively. The spatial resolution can be evaluated by the blurring of line-pair CT value in the images of CatPhan504’s CTP528 module. The noise level can be evaluated by the integral non-uniformity in the images of Cheese’s uniformity module. the low contrast resolution can be evaluated by contrast-to-noise ratio of both phantoms’ plug-in module, or visibility of the region of interest (Supra-Slice) in the images of CatPhan504’s CTP515 module. Results: Analyses on CatPhan504’s line pair module(CTP528 module) showed that the first three line pairs(the gap size are 0.500 cm, 0.250 cm and 0.167 cm respectively) could be clearly observed but blurring began to occur from the fourth line pair(the gap size is 0.125 cm) under Coarse mode. Meanwhile, the first four line pairs were all observable under the Normal and Fine modes. Integral non-integrity index(the value negatively correlated with the noise level) were 0.155 7, 0.136 8 and 0.122 9 for Coarse, Normal and Fine modes respectively. None of the Supra-Slice in CatPhan504’s CTP515 module could be observed under three imaging modes. Low contrast contrast-to-noise ratio of Cheese phantom was similar under three modes and the insert visibility exhibited nearly linear growth with the increasing difference between CT average value of the insert material and background.Conclusion: Superiority and inferiority of three image modes in terms of the three image quality index was not consistent. Evaluation results above could provide reference for more rational decision on scanning modes selection of helical tomotherapy, which was based on image visualization demands in clinical practice. The proposed method could also provide guidance for similar image quality assessment and periodic quality assurance.

Key words: Helical tomotherapy, Megavoltage computed tomography, Image Quality, Quality Assurance

中图分类号:

R815

黄宇亮,李晨光,毛凯,武建安,戴甜甜,韩媛媛,吴昊,王海洋,张艺宝. 引导螺旋断层放疗用兆伏CT图像质量定量分析[J]. 北京大学学报（医学版）, 2019, 51(3): 525-529.

Yu-liang HUANG,Chen-guang LI,Kai MAO,Jian-an WU,Tian-tian DAI,Yuan-yuan HAN,Hao WU,Hai-yang WANG,Yi-bao ZHANG. Quantitative evaluation of image quality of megavoltage computed tomography for guiding helical tomotherapy[J]. Journal of Peking University(Health Sciences), 2019, 51(3): 525-529.

图/表 5

图1

图2

表1

图3

图4

参考文献 16

[1]	Langen KM, Papanikolaou N, Balog J , et al. QA for helical tomotherapy: report of the AAPM task group 148[J]. Med Phys, 2010,37(9):4817-4853. doi: 10.1118/1.3462971
[2]	Yadav P, Tolakanahalli R, Rong Y , et al. The effect and stability of MVCT images on adaptive tomotherapy[J]. J Appl Clin Med Phys, 2010,11(4):4-14. doi: 10.1120/jacmp.v11i4.3229
[3]	Maggiulli E, Fiorino C, Passoni P , et al. Characterisation of rectal motion during neo-adjuvant radiochemotherapy for rectal cancer with image-guided tomotherapy: implications for adaptive dose escalation strategies[J]. Acta Oncol, 2012,51(3):318-324. doi: 10.3109/0284186X.2012.666358
[4]	丛小虎, 徐寿平, 解传滨 , 等. Tomotherapy系统五年质控结果及其模式的转变[J]. 中国医疗器械杂志, 2016,40(5):380-385.
[5]	李正贤, 赵晶晶, 马永乐 , 等. 医科达XVI锥形束CT头颈部扫描角度优化[J]. 中国医学物理学杂志, 2017,34(11):1106-1109.
[6]	Meeks SL, Harmon FJ, Langen K , et al. Performance characterization of megavoltage computed tomography imaging on a helical tomotherapy unit[J]. Med Phys, 2005,32(8):2673-2681. doi: 10.1118/1.1990289
[7]	刘明娜, 王谦, 杨新 , 等. 图像质量客观评价方法在 CT 图像中的应用[J]. 生物医学工程学杂志, 2011,28(2):357-364.
[8]	Zarb F, Rainford L, Mcentee MF . Image quality assessment tools for optimization of CT images[J]. Radiography, 2010,16(2):147-153. doi: 10.1016/j.radi.2009.10.002
[9]	Klein EE, Hanley J, Bayouth J , et al. Task group 142 report: quality assurance of medical accelerators[J]. Med Phys, 2009,36(9):4197-4212. doi: 10.1118/1.3190392
[10]	Zaila A, Adili M, Bamajboor S . Pylinac: a toolkit for performing TG-142 QA related tasks on linear accelerator[J]. Phys Med, 2016,32(3):292-293.
[11]	David J . Goodenough: catphan 504 manual[M]. New York: The Phantom Laboratory, 2012: 7.
[12]	Kerns JR. Pylinac Documentation: Realease 2.2.1[EB/OL]. ( 2018 -12-15)[2019-01-18]. https://buildmedia.readthedocs.org/media/pdf/pylinac/v2.2.1/pylinac.pdf .
[13]	Cheng HC, Wu VW, Liu ES , et al. Evaluation of radiation dose and image quality for the Varian cone beam computed tomography system[J]. Int J Radiat Oncol Biol Phys, 2011,80(1):291-300. doi: 10.1016/j.ijrobp.2010.06.014
[14]	Gulliksrud K, Stokke C, Martinsen AC , et al. How to measure CT image quality: variations in CT-numbers, uniformity and low contrast resolution for a CT quality assurance phantom[J]. Phys Med, 2014,30(4):521-526. doi: 10.1016/j.ejmp.2014.01.006
[15]	Alahbabi SS, Bradley DA, Nisbet A , et al. Tomotherapy evaluation for head and neck cases using two types of phantoms[J]. Radiat Phys Chem, 2014,95:323-325. doi: 10.1016/j.radphyschem.2013.04.022
[16]	Verdun FR, Racine D, Ott JG , et al. Image quality in CT: from physical measurements to model observers[J]. Phys Med, 2015,31(8):823-843. doi: 10.1016/j.ejmp.2015.08.007

Metrics

Viewed

Full text

Abstract

Cited

Shared

Discussed

Group	Location
Group	Upper left	Lower left	Upper right	Lower right	Integral non-uniformity/ (×10^-2)
Coarse	17.933	18.819	13.692	17.105	15.77
Normal	17.627	19.878	15.905	16.289	13.68
Fine	19.236	20.944	16.361	17.454	12.29

引导螺旋断层放疗用兆伏CT图像质量定量分析

Quantitative evaluation of image quality of megavoltage computed tomography for guiding helical tomotherapy

RICH HTML

PDF (PC)

摘要/Abstract

引用本文

使用本文

图/表 5

参考文献 16

相关文章 6

Metrics

本文评价

推荐阅读 10

[1]	刘宁, 何峰, 满立波, 黄广林, 王海东, 王海, 李贵忠, 王建伟. 尿动力学检查中伪像的曲线特征及影响因素分析[J]. 北京大学学报（医学版）, 2014, 46(5): 817-820.
[2]	李海燕, , 吉萍. 《药物临床试验质量管理规范》（GCP）在临床研究中的价值及我国研究者的依从情况[J]. 北京大学学报（医学版）, 2010, 42(6): 637-640.
[3]	Bin CHEN, Linda A. BRADLEY. 美国的医学遗传检测[J]. 北京大学学报（医学版）, 2006, 38(1): 35-37.
[4]	Tian-jian CHEN, Yue-ying WANG, Xi-yu HE. 临床分子诊断实验室的质量管理[J]. 北京大学学报（医学版）, 2006, 38(1): 30-32.
[5]	包黎明. 有关提高我国临床分子医学检验水平的探索和感想[J]. 北京大学学报（医学版）, 2006, 38(1): 25-27.
[6]	王斌. 中国大陆产前诊断的现状和前景[J]. 北京大学学报（医学版）, 2006, 38(1): 14-16.