乳腺良恶性肿瘤的X线征象分析

目的探讨乳腺X线征象对乳腺良恶性病变诊断准确性的价值。资料与方法对105例乳腺癌与74例乳腺良性病变X线资料进行回顾性分析。制定X线摄影中钙化形态与软组织改变对良恶性病变的判断标准,从肯定恶性到肯定良性分为五类。由3位医师使用盲法进行诊断,对其诊断结果进行病例手术的金标准检验,计算其真阳性率、真阴性率,通过受试者工作特征(ROC)曲线观察其敏感性与特异性。结果 3位医师用所制定钙化与软组织X线表现的标准对良恶性病变诊断结果平均数为肯定恶性86例,误诊1例;可能恶性22例,误诊7例;不能肯定良恶性者22.3例,其中恶性3.3例,良性19例;可能良性11.3例,误诊1例;肯定良性36.3例,误诊0.3例。经统计学计算真阳性率为80%,真阴性率为99%。ROC曲线提示有较高的特异性和敏感性。结论乳腺X线显示的钙化与软组织病变表现的类型对良恶性病变诊断具有应用价值。在X线表现不能肯定时,应进一步检查,以避免对恶性肿瘤的漏诊。     

Radiation protection of patients in diagnostic radiology: status of practice in five Eastern-European countries, based on IAEA project

The purpose of this work was to investigate status of imaging technology and practice in five countries in Eastern-European region and evaluate the impact of IAEA projects on radiation protection of patients. Information collected using standardized IAEA protocol included status of technology, practices and patient dose levels in interventional procedure, radiography, mammography and computed tomography (CT). In spite of increased number of digital units, single phase generators or units older than 30 year are still in use. Examples of obsolete practice such as using fluoroscopy for positioning, photofluorography, chest fluoroscopy and soft-beam technique for chest radiography are also in use. Modern multi-slice CT or digital mammography units are available; however, there is lack of adequate radiation protection and medical physics support in hospitals. Information on patient doses in interventional procedures, conventional radiography, mammography and CT was collected to have baseline data and corrective measures were proposed with appropriate follow up actions taken.     

Compliance With Screening Mammography Guidelines After a False-Positive Mammogram

PurposeTo assess whether women with a false-positive mammogram who do return for screening are less likely to be compliant with screening mammography guidelines than are women with a negative mammogram.MethodsThis institutional review board-approved, HIPAA-compliant retrospective cohort study includes women >40 years old who received 9,385 consecutive, nonbaseline screening mammograms between December 1, 2012 and December 31, 2013. Using linear regression, we evaluated differences in time between mammograms by prior recall status, after adjusting for location of current mammogram (outpatient office versus mobile unit) and age. Using Fisher's exact test, we evaluated the association between compliance with screening guidelines and the recall status on prior mammogram, and compared by location the proportions of noncompliant women who were recalled from prior mammogram.ResultsTime between mammograms does not differ based on prior recall status (P = .83). There is no association between compliance with screening mammography guidelines and recall status on prior mammogram (ACR guidelines P = .398, United States Preventive Services Task Force guidelines P = .416). Noncompliant women recalled on prior mammogram are more likely to undergo mammography at the outpatient office rather than the mobile unit (ACR guidelines P = .0004, United States Preventive Services Task Force guidelines P = .0032).ConclusionsA prior false-positive mammogram is not a significant deterrent to compliance with screening guidelines in those women who return for screening.     

Baseline Mammography: What Is It and Why Is It Important? A Cross-Sectional Survey of Women Undergoing Screening Mammography

Objectives

Studies have shown that having a baseline mammogram, the first screening mammogram, available for comparison at the time of interpreting a subsequent mammogram significantly decreases the potential of a false-positive examination. Our aim was to evaluate knowledge of and perception about the significance of baseline mammograms in those women undergoing screening mammography.

Characterization of microcalcification: can digital monitor zooming replace magnification mammography in full-field digital mammography?

The aim of this study was to compare the diagnostic accuracy and image quality of microcalcifications in zoomed digital contact mammography with digital magnification mammography. Three radiologists with different levels of experience in mammography reviewed 120 microcalcification clusters in 111 patients with a full-field digital mammography system relying on digital magnification mammogram (MAG) images and zoomed images from contact mammography (ZOOM) using commercially available zooming systems on monitors. Each radiologist estimated the probability of malignancy and rated the image quality and confidence rate. Performance was evaluated by sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) analysis. All three radiologists rated MAG images higher than ZOOM images for sensitivity with statistical significance (average value, 92% vs. 87%, P < 0.05) and performance by ROC analysis improved with MAG imaging. The confidence rate for diagnosis decision and the assessment of lesion characteristics were also better in MAG images than in ZOOM images with statistical significance (P < 0.0001). Digital magnification mammography can enhance diagnostic performance when characterizing microcalcifications. Images zoomed from digital contact mammography cannot serve as an alternative to direct magnification digital mammography. This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (KRF-2007-313-E00363).     

Digital mammography: An update

Digital mammography has increasingly replaced conventional film-screen mammography and has become the gold standard in combination with soft copy reading in diagnostic as well as screening settings. Large international multi-center trials were able to demonstrate at least equivalence and for some aspects superiority of digital over conventional mammography with regard to detectability of breast cancer, especially in pre/perimenopausal women, women younger than 50 years and generally in dense breasts. Especially the experienced reader may benefit form CAD with an increase of specificity. Additionally digital mammography offers options of advanced processing such as digital tomosynthesis and contrast enhanced mammography. The future of breast imaging will be fusion of different imaging systems (hybrid systems).     

Usefulness of a Small-Field Digital Mammographic Imaging System Using Parabolic Polycapillary Optics as a Diagnostic Imaging Tool: a Preliminary Study

Objective

To evaluate the efficacy for spatial resolution and radiation dose of a small-field digital mammographic imaging system using parabolic polycapillary optics.

Materials and Methods

We developed a small-field digital mammographic imaging system composed of a CCD (charge coupled device) detector and an X-ray source coupled with parabolic polycapillary optics. The spatial resolution and radiation dose according to various filters were evaluated for a small-field digital mammographic imaging system. The images of a test standard phantom and breast cancer tissue sample were obtained.

Results

The small-field digital mammographic imaging system had spatial resolutions of 12 lp/mm with molybdenum and rhodium filters with a 25-µm thickness. With a thicker molybdenum filter (100 µm thick), the system had a higher spatial resolution of 11 lp/mm and contrast of 0.48. The radiation dose for a rhodium filter with a 25-µm thickness was 0.13 mGy within a 10-mm-diameter local field. A larger field image greater than 10 mm in diameter could be obtained by scanning an object. On the small-field mammographic imaging system, microcalcifications of breast cancer tissue were clearly observed.

Conclusion

A small-field digital mammographic imaging system with parabolic polycapillary optics may be a useful diagnostic tool for providing high-resolution imaging with a low radiation dose for examination of local volumes of breast tissue.     

CAD in questions/answers Review of the literature

Generalization of breast screening programs requires an efficient double reading of the mammograms, which allows reduction of false-negative rate, but might be difficult to organize. CAD (Computed Assisted Diagnosis) is dramatically improving and is able to detect suspicious mammographic lesions, either suspicious microcalcifications, masses or architectural distorsions. CAD mammography might complete or substitute to "human" double reading. The aim of this review is to describe major CAD systems commercially available, working of CAD and to present principal results of CAD mammography. Specially, place of CAD within breast screening program, according to the results of recent prospective studies will be discussed.     

阅片者间应用数字乳腺断层合成X线成像诊断乳腺疾病的可靠性分析

目的：比较阅片者间应用全屏数字化乳腺 X 线成像(FFDM)和数字乳腺断层合成 X 线成像(DBT)对乳腺疾病诊断及BI-RADS 分类的差异,评价 DBT 在诊断乳腺肿瘤方面的应用价值。方法收集疑似乳腺疾病病例300例,所有病例均经手术病理证实,其中良性118例,恶性182例,所有患者术前均行 FFDM 及 DBT 检查。分别由4名不同年资医师独立阅片进行诊断,以病理为金标准,比较阅片者间对乳腺病变诊断的差异。采用χ2及受试者工作特征(ROC)曲线分析方法进行统计。结果高年资医师阅读 FFDM 和 DBT 的诊断正确率分别为90%和91%,曲线下面积(AUC)分别为0.891和0.899;低年资医师阅读 FFDM 和DBT 影像的诊断正确率分别为82%和90%,AUC 分别为0.801和0.891。118例良性病变中 DBT 相比 FFDM,高、低年资医师分类为 BI-RADS 4a 类及以下的病例分别由82例提高到96例、41例提高到98例,分类为 BI-RADS 4b-5类的病例分别由19例降至16例、30例降至16例。182例恶性病变中 DBT 相比 FFDM,分类为 BI-RADS 4a-5类的病例高、低年资医师分别由167例提高到169例、152例提高到167例;BI-RADS 4a 类及以下的病例分别由12例降至10例、24例降至15例。高、低年资医师阅读 FFDM 分类为 BI-RADS 0类的病例分别为22例和53例,而阅读 DBT 后二者分别降至7例和4例。结论不同年资医师阅读 DBT 可以提高诊断的准确性,BI-RADS 分类与病理结果的一致性亦更高,以低年资医师提高更为显著。DBT 对提高乳腺肿瘤的检出率及诊断准确性具有很大的潜能。     

两种摄影模式下的乳腺X射线摄影的剂量比较

目的 对比分析数字乳腺X射线断层融合成像和全数字化乳腺X射线摄影两种模式下乳腺X射线摄影剂量比较,以及平均腺体剂量与乳腺密度、压迫厚度的关系。方法 回顾性收集2020年10月至2022年5月在昆明医科大学第一附属医院行数字乳腺X射线断层融合成像（DBT）的乳腺疾病患者以及同时期在本院行全数字化乳腺X射线摄影（FFDM）的体检人群的乳腺X射线摄影资料,记录压迫厚度、压迫力度及平均腺体剂量（AGD）,由两名从事乳腺影像诊断的高年资医师依照2013年ACR BI-RADS MAMMOGRAPHY对乳腺腺体密度进行分型,分为a （腺体组织<25%）、b （腺体组织约25%~50%）、c （腺体组织约50%~75%）、d （腺体组织>75%）4型,分析在FFDM、DBT模式下,不同腺体密度、不同压迫厚度与AGD的关系。结果 无论是FFDM还是DBT模式,随着乳腺腺体密度增加AGD逐渐增加,AGD_a型b_型c_型d_型,差异有统计学意义（F=861.63、617.83、330.33、451.45、290.47,P<0.001）。行FFDM的c、d型乳腺,压迫厚度为31~40 mm时AGD较低。在相同压迫厚度下,a、b、c、d型乳腺AGD_DBT均高于AGD_FFDM,差异有统计学意义（a型：t=-17.88、-42.19、-29.90、-28.14、-24.95,P<0.001;b型：t=-49.18、-35.94、-27.25、-28.37、-24.10,P<0.001;c型：t=-11.78、-32.90、-23.13、-20.51、-18.24,P<0.001;d型：t=-7.94、-26.24、-17.24、-15.44、-13.81,P<0.001）,乳腺厚度为61~70 mm的d型乳腺AGD两者差异最大,为1.07 mGy （95%CI：0.92~1.22）。AGD与乳腺密度、压迫厚度正相关,且FFDM的相关性强于DBT。结论 乳腺X射线摄影AGD与乳腺密度、压迫厚度正相关,与FFDM相比,DBT会增加AGD,但AGD增幅在安全范围内,临床工作中行DBT检查对乳腺疾病患者有益。