计算机X射线乳腺摄影影像质量与剂量最优化研究
|
摘要
目的
比较数字乳腺摄影中手动曝光控制与常用自动曝光控制(AEC)在影像质量方面的差异,探讨能否通过图像后处理方法提高影像质量和降低病人剂量,并达到以下目的：
(1)验证乳腺数字摄影系统在现有临床诊断条件下能否降低病人剂量；
(2)探讨在不同乳腺厚度时,图像后处理对影像质量的改善程度；
(3)探讨对不同乳腺病变细节,图像后处理对影像质量的改善程度；
方法
分别选用CDMAM 3.4模体和TORMAM模体,在一套乳腺CR系统中进行5个不同厚度的曝光,每一个厚度分别进行4次不同剂量的曝光。分别为1次AEC全自动曝光和三次手动曝光,手动曝光的剂量分别为AEC曝光剂量的80%,60%,和40%。由三名观察者对模体影像进行两次评分,一次不改动显示器设置,直接对原始图像评分；一次可以任意调节显示设置至最佳显示条件。比较降低剂量后的图像结果与AEC曝光剂量的影像质量之间的差异。
结果
通过图像后处理能够改善影像质量。对于不同厚度的模体,通过图像后处理降低的病人剂量程度不一样。当等效模体厚度较低时(30,35mm),可以减少约20%-40%的剂量；当等效模体厚度增至40,45,50mm时,通过图像后处理可减少病人剂量约40%-60%。不同病变中,对于纤维丝细节,通过图像后处理可以降低20%以内的剂量；图像后处理对圆形细节的显示改善明显,剂量可降低60%；然而对于颗粒群细节,图像后处理作用不明显。
结论
(1)通过图像后处理,可以改善乳腺数字摄影中图像显示效果。
(2)通过手动曝光降低曝光剂量,并对图像进行后处理,对于不同厚度乳房可以降低病人剂量20%-60%；
(3)图像后处理对于不同类型的模拟细节,所起的作用不同。对于圆形细节,影像质量改善显著；对于纤维丝细节,影像质量有所改善；而对于颗粒群细节,通过图像后处理未看到影像质量的改善。
Objective
This study aimed to investigate the difference of image quality between manual exposure and automatice exposure control (AEC) in a digital mammography, and the effect of image post-processing on improvement of image quality. To confirm the possibility of reducing patient dose through the methods of maunual exposure and image post-processing in digital mammography.
Method
CDMAM 3.4 phantom and TORMAM phantom were selected and exposured in a CR system in 5 different phantom thickness. Under each thickness there are 4 dose levels. These corresponded to 100%,80%,60% and 40% dose. Three observers interpreted the all image. Each image was scored twice:unprocessed images and post-processed image. The differences of image quality were compared between three lower dose images and 100% dose image.
Results
The image quality can be improved through image post-processing. The patient dose could be reduced from 20% to 40% through image poss-processing when the equivalent breast thickness is 30 and 35mm. When the equivalent breast thickness up to 40,45, and 50mm, the dose can be reduced from 40% to 60%. For filament details, the dose can be reduced 20% after image post-processing.For the circular details, the effects of image post-processing appear to significant and the dose can be reduced by 60%. However for the partical details, the effect of image post-processing on image quality is not obvious.
Conclusions
The image quality can be improved through image post-processing. For different equivalent breast thickness, the patient dose can be reduced from 20% to 60% through manual exposure and image post-processing. The effects of image post-processing are different on different phantom details.For filament details and circular details, the improvement of image quality is significant.The dose can be decreased by within 20% and 60% separately. However for the partical details, the effect of image post-processing on image quality is not obvious.
比较数字乳腺摄影中手动曝光控制与常用自动曝光控制(AEC)在影像质量方面的差异,探讨能否通过图像后处理方法提高影像质量和降低病人剂量,并达到以下目的：
(1)验证乳腺数字摄影系统在现有临床诊断条件下能否降低病人剂量；
(2)探讨在不同乳腺厚度时,图像后处理对影像质量的改善程度；
(3)探讨对不同乳腺病变细节,图像后处理对影像质量的改善程度；
方法
分别选用CDMAM 3.4模体和TORMAM模体,在一套乳腺CR系统中进行5个不同厚度的曝光,每一个厚度分别进行4次不同剂量的曝光。分别为1次AEC全自动曝光和三次手动曝光,手动曝光的剂量分别为AEC曝光剂量的80%,60%,和40%。由三名观察者对模体影像进行两次评分,一次不改动显示器设置,直接对原始图像评分；一次可以任意调节显示设置至最佳显示条件。比较降低剂量后的图像结果与AEC曝光剂量的影像质量之间的差异。
结果
通过图像后处理能够改善影像质量。对于不同厚度的模体,通过图像后处理降低的病人剂量程度不一样。当等效模体厚度较低时(30,35mm),可以减少约20%-40%的剂量；当等效模体厚度增至40,45,50mm时,通过图像后处理可减少病人剂量约40%-60%。不同病变中,对于纤维丝细节,通过图像后处理可以降低20%以内的剂量；图像后处理对圆形细节的显示改善明显,剂量可降低60%；然而对于颗粒群细节,图像后处理作用不明显。
结论
(1)通过图像后处理,可以改善乳腺数字摄影中图像显示效果。
(2)通过手动曝光降低曝光剂量,并对图像进行后处理,对于不同厚度乳房可以降低病人剂量20%-60%；
(3)图像后处理对于不同类型的模拟细节,所起的作用不同。对于圆形细节,影像质量改善显著；对于纤维丝细节,影像质量有所改善；而对于颗粒群细节,通过图像后处理未看到影像质量的改善。
Objective
This study aimed to investigate the difference of image quality between manual exposure and automatice exposure control (AEC) in a digital mammography, and the effect of image post-processing on improvement of image quality. To confirm the possibility of reducing patient dose through the methods of maunual exposure and image post-processing in digital mammography.
Method
CDMAM 3.4 phantom and TORMAM phantom were selected and exposured in a CR system in 5 different phantom thickness. Under each thickness there are 4 dose levels. These corresponded to 100%,80%,60% and 40% dose. Three observers interpreted the all image. Each image was scored twice:unprocessed images and post-processed image. The differences of image quality were compared between three lower dose images and 100% dose image.
Results
The image quality can be improved through image post-processing. The patient dose could be reduced from 20% to 40% through image poss-processing when the equivalent breast thickness is 30 and 35mm. When the equivalent breast thickness up to 40,45, and 50mm, the dose can be reduced from 40% to 60%. For filament details, the dose can be reduced 20% after image post-processing.For the circular details, the effects of image post-processing appear to significant and the dose can be reduced by 60%. However for the partical details, the effect of image post-processing on image quality is not obvious.
Conclusions
The image quality can be improved through image post-processing. For different equivalent breast thickness, the patient dose can be reduced from 20% to 60% through manual exposure and image post-processing. The effects of image post-processing are different on different phantom details.For filament details and circular details, the improvement of image quality is significant.The dose can be decreased by within 20% and 60% separately. However for the partical details, the effect of image post-processing on image quality is not obvious.
引文
[1]杨玲,李连弟,陈育德,等.中国乳腺癌发病死亡趋势的估计与预测.中华肿瘤杂志,2006,28(6)：438-440.
[2]李连弟,饶克勤,张思维等.中国12市县1993年-1997年肿瘤发病和死亡登记资料统计分析.中国肿瘤,2002,11(9)：497-507.
[3]张思维,陈万青,孔灵芝等.中国部分市县1998-2002年恶性肿瘤的发病与死亡.中国肿瘤,2006,15(7)：430-448
[4]中国人口协会.中国乳腺疾病调查报告.北京：2010
[5]Otha WL, David A. Schauer. Mammography:Better, Safer, and More Effective? Radiology,2006,240:3-5.
[6]Kerlikowske K, GradyD, Rubin SM, et al. Efficacy of screening mammography:a meta analysis. JAMA 1995,273:149-154.
[7]岳保荣.乳腺普查的发展与展望.世界医疗器械,2008,14(11)：22-23.
[8]岳保荣,尉可道.正确选用乳腺普查放射技术.中华放射医学与防护杂志,2006,26(6)：547-548.
[9]Bloomquist AK,Yaffe MJ,Pisano ED, et al.Quality control for digital mammography in the ACRIN DMIST trial:part Ⅰ..Med Phys,2006,33(3): 719-736.
[10]Yaffe MJ, Bloomquist AK,Mawdsley GE,et al. Quality control for digital mammography:part Ⅱ. Recommendations from the ACRIN DMIST trial. Med Phys,2006,33(3):737-752.
[11]UNSCEAR.2000 Report to the General Assembly with Scientific Annexes. UN. New York,2000.97-105.
[12]Law J. Risk and benefit associated with radiation dose in breast screening programmes,an update. British Journal of Radiology.1995,68:870-876.
[13]ICRP Publication 60,1990 recommendations of the International Commission on Radiological Protection, Annals of the ICRP 1991;21.
[14]ICRP Publication 103. The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP 2007;37 (2-4).
[15]Svahn T,Hemdal B,Ruschin M, et al.Dose reduction and its influence on diagnostic accuracy and radiation risk in digital mammography:an observer performance study using an anthropomorphic breast phantom.British Journal of Radiology,2007,80(955):557-562
[16]Williams MB,Raghunathan P,More MJ, et al.Optimization of exposure parameters in full field digital mammography.Medical Physics,2008, 35(6):2414-2423
[17]Samei E, Saunders RS Jr, Baker JA, et al.Digital Mammography-Effects of Reduced Radiation Dose on Diagnostic Performance. Radiology,2007, 243(2):396-404
[18]Young KC,Oduko JM, Bosmans H, et al.Optimal beam quality selection in digital mammography.British Journal of Radiology,2006,.79 (948):981-990.
[19]Dance DR,Thilander AK,Sandborg M. Influence of anode/filter material and tube potential on contrast, signal-to-noise ratio and average absorbed dose in mammography:a Monte Carlo study.British Journal of Radiology, 2000,.874(2000):1056-1067.
[20]Huda W,Sajewicz AM. Experimental investigation of the dose and image quality characteristics of a digital mammography imaging system. Medical Physics,2003,30(3):442-448.
[21]Obenauer S,Hermann KP,Grabbe E.Dose reduction in full-field digital mammography:an anthropomorphic breast phantom study.British Journal of Radiology,2003,76(907):478-482.
[22]B Hemdal, I Andersson, A. Grahn, et al.can the average glandular dose in routine digital mammography dcreening reduced? A pilot study using revised image quality criteria. Radiation Protection Dosimetry,2005,114(1/3):383-388
[23]Chantal VO,Andre VS,Catherine G. Clinical image quality criteria for full field digital mammography:a first practical application..Radiation Protection Dosimetry,2008,129 (1/3):265-270
[24]Alan H. Baydush,Carey E. Floyd et al.Improved image quality in digital mammography with image processing..Medical Physics,2000,27(6) 1503-1508
[25]Pisano ED,Cole EB,Major S, et al. Radiologists' preferences for digital mammographic display. The International Digital Mammography Development Group. Radiology,2000,216(3),2000.820-830
[26]丁文洪.乳腺计算机X射线摄影曝光条件的研究.中华放射医学与防护杂志,2008,28(4)：410-412
[27]罗小梅周德安冯仕庭.低剂量CR乳腺钼靶摄影的应用研究.中华实用中西医杂志,2008,21(14)：1216-1217
[28]宛然,武春雪.乳腺摄影降低辐射量的优化选择.放射学实践,2008,23(8)：838-840
[29]赵永霞,宋少娟.两种数字乳腺X射线摄影系统的比较.中华放射医学与防护杂志,2008,28(4)：412-415
[30]王晓枫张立娜黄砚玲.数字化钼、铑双靶乳腺摄影中患者吸收剂量的比较.中国辐射卫生,2005,14(4)：274-275
[31]李石银,杜国生,燕树林,等.CR与屏/片系统乳腺摄影影像质量的比对研究.中国医学装备,2005,2(7)：1-3
[32]薛克,闫黎明,李堃,等.计算机X线摄影(CR)技术在乳腺疾病诊断中的应用.现代医用影像学,2007,16(3)：129-131
[33]朱少萍,张妙芳,麦耀文.全数字化乳腺X线摄影与传统乳腺X线摄影对比分析.放射学实践,2007,22(10)：1110-1112
[34]李桂华,曹桂景,郁成.CR与屏-胶系统摄影在乳腺疾病诊断中的价值.医学影像学杂志,2007,17(2)：120-122
[35]李悦,徐寿良.CR影像的质量控制.实用放射学杂志,2004,20(4)：372-372
[36]杨青,张克云.CR在乳腺平片中的应用.现代医用影像学,2005,14(6)：271-272.
[37]燕树林.乳腺X线摄影与质量控制.北京：人民军医出版社,2008.
[38]赵永霞.数字乳腺X线摄影各系统影像质量与辐射剂量的比较研究.山东：泰山医学院,2008
[39]张泽宝.医学影像物理学.第二版.北京：人民卫生出版社,2006
[40]GBZ 186-2006,乳腺X射线摄影质量控制检测规范
[41]European Commission. European Guidelines for Quality Assurance in Breast Cancer Screening and Diagnosis,4th edition. Luxembourg:2006
[42]吴恩惠.医学影像学.第五版.北京：人民卫生出版社,2006
[43]ICRU Report 74. Patient Dosimetry for X Rays Used in Medical Imaging. Journal of the ICRU 2005;5(2).
[44]MAO Thijssen, KR Bijkerk. Contrast-detail phantom artinis CDMAM type 3.4 manual.
[45]leeds test objects limited. TORMAM test object manual.
[2]李连弟,饶克勤,张思维等.中国12市县1993年-1997年肿瘤发病和死亡登记资料统计分析.中国肿瘤,2002,11(9)：497-507.
[3]张思维,陈万青,孔灵芝等.中国部分市县1998-2002年恶性肿瘤的发病与死亡.中国肿瘤,2006,15(7)：430-448
[4]中国人口协会.中国乳腺疾病调查报告.北京：2010
[5]Otha WL, David A. Schauer. Mammography:Better, Safer, and More Effective? Radiology,2006,240:3-5.
[6]Kerlikowske K, GradyD, Rubin SM, et al. Efficacy of screening mammography:a meta analysis. JAMA 1995,273:149-154.
[7]岳保荣.乳腺普查的发展与展望.世界医疗器械,2008,14(11)：22-23.
[8]岳保荣,尉可道.正确选用乳腺普查放射技术.中华放射医学与防护杂志,2006,26(6)：547-548.
[9]Bloomquist AK,Yaffe MJ,Pisano ED, et al.Quality control for digital mammography in the ACRIN DMIST trial:part Ⅰ..Med Phys,2006,33(3): 719-736.
[10]Yaffe MJ, Bloomquist AK,Mawdsley GE,et al. Quality control for digital mammography:part Ⅱ. Recommendations from the ACRIN DMIST trial. Med Phys,2006,33(3):737-752.
[11]UNSCEAR.2000 Report to the General Assembly with Scientific Annexes. UN. New York,2000.97-105.
[12]Law J. Risk and benefit associated with radiation dose in breast screening programmes,an update. British Journal of Radiology.1995,68:870-876.
[13]ICRP Publication 60,1990 recommendations of the International Commission on Radiological Protection, Annals of the ICRP 1991;21.
[14]ICRP Publication 103. The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP 2007;37 (2-4).
[15]Svahn T,Hemdal B,Ruschin M, et al.Dose reduction and its influence on diagnostic accuracy and radiation risk in digital mammography:an observer performance study using an anthropomorphic breast phantom.British Journal of Radiology,2007,80(955):557-562
[16]Williams MB,Raghunathan P,More MJ, et al.Optimization of exposure parameters in full field digital mammography.Medical Physics,2008, 35(6):2414-2423
[17]Samei E, Saunders RS Jr, Baker JA, et al.Digital Mammography-Effects of Reduced Radiation Dose on Diagnostic Performance. Radiology,2007, 243(2):396-404
[18]Young KC,Oduko JM, Bosmans H, et al.Optimal beam quality selection in digital mammography.British Journal of Radiology,2006,.79 (948):981-990.
[19]Dance DR,Thilander AK,Sandborg M. Influence of anode/filter material and tube potential on contrast, signal-to-noise ratio and average absorbed dose in mammography:a Monte Carlo study.British Journal of Radiology, 2000,.874(2000):1056-1067.
[20]Huda W,Sajewicz AM. Experimental investigation of the dose and image quality characteristics of a digital mammography imaging system. Medical Physics,2003,30(3):442-448.
[21]Obenauer S,Hermann KP,Grabbe E.Dose reduction in full-field digital mammography:an anthropomorphic breast phantom study.British Journal of Radiology,2003,76(907):478-482.
[22]B Hemdal, I Andersson, A. Grahn, et al.can the average glandular dose in routine digital mammography dcreening reduced? A pilot study using revised image quality criteria. Radiation Protection Dosimetry,2005,114(1/3):383-388
[23]Chantal VO,Andre VS,Catherine G. Clinical image quality criteria for full field digital mammography:a first practical application..Radiation Protection Dosimetry,2008,129 (1/3):265-270
[24]Alan H. Baydush,Carey E. Floyd et al.Improved image quality in digital mammography with image processing..Medical Physics,2000,27(6) 1503-1508
[25]Pisano ED,Cole EB,Major S, et al. Radiologists' preferences for digital mammographic display. The International Digital Mammography Development Group. Radiology,2000,216(3),2000.820-830
[26]丁文洪.乳腺计算机X射线摄影曝光条件的研究.中华放射医学与防护杂志,2008,28(4)：410-412
[27]罗小梅周德安冯仕庭.低剂量CR乳腺钼靶摄影的应用研究.中华实用中西医杂志,2008,21(14)：1216-1217
[28]宛然,武春雪.乳腺摄影降低辐射量的优化选择.放射学实践,2008,23(8)：838-840
[29]赵永霞,宋少娟.两种数字乳腺X射线摄影系统的比较.中华放射医学与防护杂志,2008,28(4)：412-415
[30]王晓枫张立娜黄砚玲.数字化钼、铑双靶乳腺摄影中患者吸收剂量的比较.中国辐射卫生,2005,14(4)：274-275
[31]李石银,杜国生,燕树林,等.CR与屏/片系统乳腺摄影影像质量的比对研究.中国医学装备,2005,2(7)：1-3
[32]薛克,闫黎明,李堃,等.计算机X线摄影(CR)技术在乳腺疾病诊断中的应用.现代医用影像学,2007,16(3)：129-131
[33]朱少萍,张妙芳,麦耀文.全数字化乳腺X线摄影与传统乳腺X线摄影对比分析.放射学实践,2007,22(10)：1110-1112
[34]李桂华,曹桂景,郁成.CR与屏-胶系统摄影在乳腺疾病诊断中的价值.医学影像学杂志,2007,17(2)：120-122
[35]李悦,徐寿良.CR影像的质量控制.实用放射学杂志,2004,20(4)：372-372
[36]杨青,张克云.CR在乳腺平片中的应用.现代医用影像学,2005,14(6)：271-272.
[37]燕树林.乳腺X线摄影与质量控制.北京：人民军医出版社,2008.
[38]赵永霞.数字乳腺X线摄影各系统影像质量与辐射剂量的比较研究.山东：泰山医学院,2008
[39]张泽宝.医学影像物理学.第二版.北京：人民卫生出版社,2006
[40]GBZ 186-2006,乳腺X射线摄影质量控制检测规范
[41]European Commission. European Guidelines for Quality Assurance in Breast Cancer Screening and Diagnosis,4th edition. Luxembourg:2006
[42]吴恩惠.医学影像学.第五版.北京：人民卫生出版社,2006
[43]ICRU Report 74. Patient Dosimetry for X Rays Used in Medical Imaging. Journal of the ICRU 2005;5(2).
[44]MAO Thijssen, KR Bijkerk. Contrast-detail phantom artinis CDMAM type 3.4 manual.
[45]leeds test objects limited. TORMAM test object manual.