Effectiveness and cost-effectiveness of double reading in digital mammography screening: A systematic review and meta-analysis.

Science.gov (United States)

Posso, Margarita; Puig, Teresa; Carles, Misericòrdia; Rué, Montserrat; Canelo-Aybar, Carlos; Bonfill, Xavier

2017-11-01

Double reading is the strategy of choice for mammogram interpretation in screening programmes. It remains, however, unknown whether double reading is still the strategy of choice in the context of digital mammography. Our aim was to determine the effectiveness and cost-effectiveness of double reading versus single reading of digital mammograms in screening programmes. We performed a systematic review by searching the PubMed, Embase, and Cochrane Library databases up to April 2017. We used the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies) tool and CHEERS (Consolidated Health Economic Evaluation Reporting Standards) checklist to assess the methodological quality of the diagnostic studies and economic evaluations, respectively. A proportion's meta-analysis approach, 95% Confidence Intervals (95% CI) and test of heterogeneity (P values) were used for pooled results. Costs are expressed US$ PPP (United States Dollar purchasing power parities). The PROSPERO ID of this Systematic Review's protocol is CRD42014013804. Of 1473 potentially relevant hits, four high-quality studies were included. The pooled cancer detection rate of double reading was 6.01 per 1000 screens (CI: 4.47‰-7.77‰), and it was 5.65 per 1000 screens (CI: 3.95‰-7.65‰) for single reading (P=0.76). The pooled proportion of false-positives of double reading was 47.03 per 1000 screens (CI: 39.13‰-55.62‰) and it was 40.60 per 1000 screens (CI: 38.58‰-42.67‰) for single reading (P=0.12). One study reported, for double reading, an ICER (Incremental Cost-Effectiveness Ratio) of 16,684 Euros (24,717 US$ PPP; 2015 value) per detected cancer. Single reading+CAD (computer-aided-detection) was cost-effective in Japan. The evidence of benefit for double reading compared to single reading for digital mammography interpretation is scarce. Double reading seems to increase operational costs, have a not significantly higher false-positive rate, and a similar cancer detection rate. Copyright �

Physical image quality of computed radiography in mammography system

International Nuclear Information System (INIS)

Norriza Mohd Isa; Muhammad Jamal Isa; Wan Muhamad Saridan Wan Hassan; Fatimah Othman

2013-01-01

Full-text: Mammography is a screening procedure that mostly used for early detection of breast cancer. In digital imaging system, Computed Radiography is a cost-effective technology that applied indirect conversion detector. The paper presents physical image quality parameter measurements namely modulation transfer function (MTF), normalized noise power spectrum (NNPS) and detective quantum efficiency (DQE) of Computed Radiography in mammography system. MTF was calculated from two different orientations of slanted images of an edge test device and NNPS was estimated using flat-field image. Both images were acquired using a standard mammography beam quality. DQE was determined by applying the MTF and NNPS values into our developed software program. Both orientations have similar DQE characteristics. (author)

Computed Radiography Exposure Indices in Mammography | Koen ...

African Journals Online (AJOL)

Computed Radiography Exposure Indices in Mammography. L Koen, C Herbst, W Rae. Abstract. Background. Studies indicate that computed radiography (CR) can lead to increased radiation dose to patients. It is therefore important to relate the exposure indicators provided by CR manufacturers to the radiation dose ...

CAD in breast imaging. Application in mammography and MR mammography

International Nuclear Information System (INIS)

Obenauer, S.; Hermann, K.P.

2012-01-01

Computer aided diagnosis systems (CAD-systems) are evaluated in different parts of diagnostic imaging. In breast imaging double reading which is time- and cost spending is necessary. Therefore a lot of studies evaluated the use of CAD-systems in mammography. However the rate of false-positives is too high to implement CAD-systems as double reader in routine work. In the future, improvements in this technique could perhaps change the performance of CAD-systems. (orig.)

Studies Comparing Screen-Film Mammography and Full-Field Digital Mammography in Breast Cancer Screening: Updated Review

International Nuclear Information System (INIS)

Skaane, P.

2009-01-01

Full-field digital mammography (FFDM) has several potential benefits as compared with screen-film mammography (SFM) in mammography screening. Digital technology also opens for implementation of advanced applications, including computer-aided detection (CAD) and tomosynthesis. Phantom studies and experimental clinical studies have shown that FFDM is equal or slightly superior to SFM for detection and characterization of mammographic abnormalities. Despite obvious advantages, the conversion to digital mammography has been slower than anticipated, and not only due to higher costs. Until very recently, some countries did not even permit the use of digital mammography in breast cancer screening. The reason for this reluctant attitude was concern about lower spatial resolution and about using soft-copy reading. Furthermore, there was a lack of data supporting improved diagnostic accuracy using FFDM in a screening setting, since two pioneer trials both showed nonsignificantly lower cancer detection rate at FFDM. The 10 studies comparing FFDM and SFM in mammography screening published so far have shown divergent and rather conflicting results. Nevertheless, there is a rapid conversion to digital mammography in breast cancer screening in many western countries. The aim of this article is to give an updated review of these studies, discuss the conflicting findings, and draw some conclusions from the results

The influence of software filtering in digital mammography image quality

Science.gov (United States)

Michail, C.; Spyropoulou, V.; Kalyvas, N.; Valais, I.; Dimitropoulos, N.; Fountos, G.; Kandarakis, I.; Panayiotakis, G.

2009-05-01

Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

The influence of software filtering in digital mammography image quality

International Nuclear Information System (INIS)

Michail, C; Spyropoulou, V; Valais, I; Panayiotakis, G; Kalyvas, N; Fountos, G; Kandarakis, I; Dimitropoulos, N

2009-01-01

Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

Cone-beam micro computed tomography dedicated to the breast.

Science.gov (United States)

Sarno, Antonio; Mettivier, Giovanni; Di Lillo, Francesca; Cesarelli, Mario; Bifulco, Paolo; Russo, Paolo

2016-12-01

We developed a scanner for micro computed tomography dedicated to the breast (BµCT) with a high resolution flat-panel detector and a microfocus X-ray tube. We evaluated the system spatial resolution via the 3D modulation transfer function (MTF). In addition to conventional absorption-based X-ray imaging, such a prototype showed capabilities for propagation-based phase-contrast and related edge enhancement effects in 3D imaging. The system limiting spatial resolution is 6.2mm -1 (MTF at 10%) in the vertical direction and 3.8mm -1 in the radial direction, values which compare favorably with the spatial resolution reached by mini focus breast CT scanners of other groups. The BµCT scanner was able to detect both microcalcification clusters and masses in an anthropomorphic breast phantom at a dose comparable to that of two-view mammography. The use of a breast holder is proposed in order to have 1-2min long scan times without breast motion artifacts. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Trimodel Mammography with Perfect Coregistration

Science.gov (United States)

2017-02-01

background, the major confounding factor in reading mammography; the imaging characteristics suggest that this contrast mechanism would be preferable...image with enhanced edges and reduced anatomical background, the major confounding factor in reading mammography; the imaging characteristics suggest...subjects, vertebrate animals , biohazards, and/or select agents Describe significant deviations, unexpected outcomes, or changes in approved protocols

Assessment of the usefulness of telemammography for the second reading in screening mammography

International Nuclear Information System (INIS)

Okuda, Itsuko; Nakajima, Yasuo; Okazaki, Hiroko; Shimamoto, Hiroshi; Okamoto, Kyoko; Kanemaki, Yoshihide; Irimoto, Masahiro

2010-01-01

We assessed the usefulness of telemammography by soft-copy diagnosis. A wide area network for teleradiology was set up incorporating seven institutions located in two prefectures. A total of 1053 subjects were enrolled. The first reading was performed using hard-copy images at the institution where mammography was undertaken. The second reading using hard-copy images was then performed. These images were transferred to our institution, where a second reading based on soft-copy images was performed. The result of soft-copy diagnosis were then compared with those of the hard-copy diagnosis. The diagnosis concordance rate, which was higher than category 3, was evaluated. Category 1 or 2 accounted for 956 cases at the stage of the second hard-copy diagnosis, of which category 1 or 2 accounted for 930 cases analyzed in the second soft-copy diagnosis. A category higher than 3 accounted for 97 cases at the second hard-copy diagnosis, of which a category higher than 3 accounted for 75 cases at the stage of the second soft-copy diagnosis. The κ-value for the diagnosis concordance rate was 0.751. The diagnostic concordance between hard-copy diagnosis and soft-copy diagnosis was good. Diagnostic accuracy showed no significant difference between the two. We conclude that soft-copy diagnosis by telemammography is useful, and that its application is desirable for screening mammography. (author)

Follow-up of bone lesions in an experimental multiple myeloma mouse model: Description of an in vivo technique using radiography dedicated for mammography

NARCIS (Netherlands)

Vanderkerken, K.; Goes, E.; Raeve, H. de; Radl, J.; Camp, B. van

1996-01-01

The evolution of bone lesions in transplantable C57BL/KaLwRij 5T mouse myeloma (MM) has been followed in vivo. Mice were anaesthetised and a radiograph of the pelvis and hind legs was performed by a radiograph dedicated for mammography. This is the first description of an in vivo technique under

TL dosimetry for quality control of CR mammography imaging systems

Science.gov (United States)

Gaona, E.; Nieto, J. A.; Góngora, J. A. I. D.; Arreola, M.; Enríquez, J. G. F.

The aim of this work is to estimate the average glandular dose with thermoluminescent (TL) dosimetry and comparison with quality imaging in computed radiography (CR) mammography. For a measuring dose, the Food and Drug Administration (FDA) and the American College of Radiology (ACR) use a phantom, so that dose and image quality are assessed with the same test object. The mammography is a radiological image to visualize early biological manifestations of breast cancer. Digital systems have two types of image-capturing devices, full field digital mammography (FFDM) and CR mammography. In Mexico, there are several CR mammography systems in clinical use, but only one system has been approved for use by the FDA. Mammography CR uses a photostimulable phosphor detector (PSP) system. Most CR plates are made of 85% BaFBr and 15% BaFI doped with europium (Eu) commonly called barium flourohalideE We carry out an exploratory survey of six CR mammography units from three different manufacturers and six dedicated X-ray mammography units with fully automatic exposure. The results show three CR mammography units (50%) have a dose greater than 3.0 mGy without demonstrating improved image quality. The differences between doses averages from TLD system and dosimeter with ionization chamber are less than 10%. TLD system is a good option for average glandular dose measurement for X-rays with a HVL (0.35-0.38 mmAl) and kVp (24-26) used in quality control procedures with ACR Mammography Accreditation Phantom.

Daily quality control in computed radiography mammography using the manufacturer phantom

International Nuclear Information System (INIS)

Jakubiak, Rosangela R.; Messias, Pricila C.; Oliveira, Carlla M.

2011-01-01

The quality control (QC) in mammography system involves a large amount of test tools, which implies a large space for storage and a high number of exposure. This work describes a QC system using a phantom, Fuji Computed Radiography (FCR) One Shot Phantom M Plus, that evaluates several parameters with just one exposure. The software offers tests with annual, semi-annual, quarterly, weekly and daily periodicity, and analyzes the conformities of the mammography equipment, image plate and cassettes. Because of the high number of tests, it was evaluated the daily test only for seven months in two mammography equipment. The test, through the software and its image, allows the analysis of ten parameters in QC. The evaluation of these parameters was realized by the average of the values provided by the software. Only one of the evaluated items showed not conformity, but this was observed and the necessary corrections were realized. The monitoring of use of FCR Mammography QC software with the FCR One Shot Phantom M Plus was realized and through this we could investigate that the quality program provided by the system is appropriate for the radiology services that has the Fuji Computed Radiography system. (author)

The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening

DEFF Research Database (Denmark)

Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm

2018-01-01

Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR......) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were...... excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences...

Computer-aided diagnostics of screening mammography using content-based image retrieval

Science.gov (United States)

Deserno, Thomas M.; Soiron, Michael; de Oliveira, Júlia E. E.; de A. Araújo, Arnaldo

2012-03-01

Breast cancer is one of the main causes of death among women in occidental countries. In the last years, screening mammography has been established worldwide for early detection of breast cancer, and computer-aided diagnostics (CAD) is being developed to assist physicians reading mammograms. A promising method for CAD is content-based image retrieval (CBIR). Recently, we have developed a classification scheme of suspicious tissue pattern based on the support vector machine (SVM). In this paper, we continue moving towards automatic CAD of screening mammography. The experiments are based on in total 10,509 radiographs that have been collected from different sources. From this, 3,375 images are provided with one and 430 radiographs with more than one chain code annotation of cancerous regions. In different experiments, this data is divided into 12 and 20 classes, distinguishing between four categories of tissue density, three categories of pathology and in the 20 class problem two categories of different types of lesions. Balancing the number of images in each class yields 233 and 45 images remaining in each of the 12 and 20 classes, respectively. Using a two-dimensional principal component analysis, features are extracted from small patches of 128 x 128 pixels and classified by means of a SVM. Overall, the accuracy of the raw classification was 61.6 % and 52.1 % for the 12 and the 20 class problem, respectively. The confusion matrices are assessed for detailed analysis. Furthermore, an implementation of a SVM-based CBIR system for CADx in screening mammography is presented. In conclusion, with a smarter patch extraction, the CBIR approach might reach precision rates that are helpful for the physicians. This, however, needs more comprehensive evaluation on clinical data.

Full-field digital mammography versus computed radiology mammography: comparison in image quality and radiation dose

International Nuclear Information System (INIS)

Zhao Yongxia; Song Shaojuan; Liu Chuanya; Qi Hengtao; Qin Weichang

2008-01-01

Objective: To investigate the differences in image quality and radiation dose between full- field digital mammography (FFDM) system and compute radiology mammography (CRM) system. Methods: The ALVIM mammographic phantom was exposed by FFDM system with automatic exposure control (AEC) and then exposed by CRM system with the unique imaging plank on the same condition. The FFDM system applied the same kV value and the different mAs values (14, 16, 18, 22 and 24 mAs), and the emission skin dose (ESD) and the average gland dose (AGD) were recorded for the above-mentioned exposure factors. All images were read by five experienced radiologists under the same condition and judged based on 5-point scales. And then receive operating characteristic (ROC) curve was drawn and the probability (P det ) values were calculated. The data were statistically processed with ANOVA. Results: The P det values of calcifications and lesion lump were higher with FFDM system than with CRM system at the same dose (1.36 mGy). Especially, for microcalcifications and lesion lump, the largest difference of the P det value was 0.215, and that of lesion lump was 0.245. In comparison with CRM system, the radiation dose of FFDM system could be reduced at the same P det value. The ESD value was reduced by 26%, and the ACD value was reduced by 41%. When the mAs value exceed AEC value, the P det value almost had no change, though the radiation dose was increased. Conclusions: The detection rates of microcalcifications and lesion lump with FFDM system are proven to be superior to CRM system at the same dose. The radiation dose of FFDM system was less than CRM system for the same image quality. (authors)

Comparison of low contrast detectability of computed tomography and screen/film mammography systems

International Nuclear Information System (INIS)

Noriah Jamal; Kwan Hoong Ng; McLean, D.

2006-01-01

The objective of this study was to compare low contrast detectability of computed radiography (CR) and screen/film (SF) mammography systems. The Nijimegen contrast detail test object (CDMAM type 3.4) was imaged at 28 kV, in automatic exposure control mode separately. Six medical imaging physicists read each CDMAM phantom image. Contrast detail curves were plotted to compare low contrast detectability of CR (soft copy and hard copy) and SF mammography systems. Effect of varying exposure parameters, namely kV, object position inside the breast phantom, and entrance surface exposure (ESE) on the contrast detail curve were also investigated using soft copy CR. The significant of the difference of contrast between CR and SF, and for each exposure parameter was tested using non-parametric Kruskal-Wallis test. We found that the low contrast detectability of CR (soft copy and hard copy) system is not significantly different to that of SF system (p>0.05, Kruskal-Wallis test). For CR soft copy, no significant relationship (p>0.05, Kruskal-Wallis test) was seen for variation of kV, object position inside the breast phantom and ESE. This indicates that CR is comparable with SF for useful detection and visualization of low contrast objects such as small low contrast areas corresponding to breast pathology

The accuracy of digital breast tomosynthesis compared with coned compression magnification mammography in the assessment of abnormalities found on mammography

International Nuclear Information System (INIS)

Morel, J.C.; Iqbal, A.; Wasan, R.K.; Peacock, C.; Evans, D.R.; Rahim, R.; Goligher, J.; Michell, M.J.

2014-01-01

Aim: To compare the diagnostic accuracy of the digital breast tomosynthesis (DBT) with coned compression magnification mammography (CCMM). Materials and methods: The study design included two reading sessions completed by seven experienced radiologists. In the first session, all readers read bilateral standard two-view mammograms and a CCMM view of the lesion before giving a combined score for assessment. In the second session, readers read bilateral standard two-view mammograms plus one-view DBT. The two reading sessions of the experiment were separated by at least 2 weeks to reduce the chance of reader memory of the images read in the previous session from influencing the performance in the subsequent session. Results: Three hundred and fifty-four lesions were assessed and receiver-operative characteristic (ROC) analysis was used to evaluate the difference between the two modes. For standard two-view mammography plus CCMM, the area under the curve (AUC) was 0.87 [95% confidence interval (CI): 0.83–0.91] and for standard two-view mammography plus DBT the AUC was 0.93 (95% CI: 0.91–0.95). The difference between the AUCs was 0.06 with p-value of 0.0014. Conclusion: Two-view mammography with one-view DBT showed significantly improved accuracy compared to two-view mammography and CCMM in the assessment of mammographic abnormalities. These results show that DBT can be used effectively in the further evaluation of mammographic abnormalities found at screening and in symptomatic diagnostic practice. - Highlights: • Diagnostic accuracy of magnification mammography and digital breast tomosynthesis. • There is statistical difference between CCMM and DBT. • DBT has a role in evaluating mammographic abnormalities

Film-Screen Mammography versus digital storage plate mammography: Hard copy and monitor display of microcalcifications and focal findings - A retrospective clinical and histologic analysis

International Nuclear Information System (INIS)

Schulz-Wendtland, R.; Wenkel, E.; Aichinger, U.; Tartsch, M.; Kuchar, I.; Bautz, W.

2003-01-01

Purpose: A retrospective clinical-histological study to determine the diagnostic accuracy of mammography using conventional screen-film cassettes (hard copy), high-resolution digital phosphor storage plates (hard copy) and monitor display (soft copy) for microcalcifications and focal lesions (BI-RADS TM category 4 or 5). Materials and methods: From April to November 2001, 76 patients underwent conventional film-screen mammography and, after diagnosis and preoperative wire localization, digital mammography with the same exposure parameters. Five investigators retrospectively determined the diagnosis after the operation from randomly distributed mediolateral views (hard-copy reading) and from the monitor display (soft-copy reading). These results were correlated with the final histology. Results: The accuracy of conventional screen-film mammography, digital mammography and monitor-displayed mammography was 67%, 65% and 68% for all findings, (n = 76), 59%, 59% and 68% for microcalcifications (n = 44) and 75%, 72% and 63% for focal lesions (n = 32). The overall results showed no difference. Conclusions: Our findings indicate equivalence of conventional screen-film mammography, high-resolution digital phosphor storage plate mammography and monitor-displayed mammography. (orig.) [de

Mammography accreditation program

Energy Technology Data Exchange (ETDEWEB)

Wilcox, P.

1993-12-31

In the mid-1980`s, the movement toward the use of dedicated mammography equipment provided significant improvement in breast cancer detection. However, several studies demonstrated that this change was not sufficient to ensure optimal image quality at a low radiation dose. In particular, the 1985 Nationwide Evaluation of X-ray Trends identified the wide variations in image quality and radiation dose, even from dedicated units. During this time period, the American Cancer Society (ACS) launched its Breast Cancer Awareness Screening Campaign. However, there were concerns about the ability of radiology to respond to the increased demand for optimal screening examinations that would result from the ACS program. To respond to these concerns, the ACS and the American College of Radiology (ACR) established a joint committee on mammography screening in 1986. After much discussion, it was decided to use the ACR Diagnostic Practice Accreditation Program as a model for the development of a mammography accreditation program. However, some constraints were required in order to make the program meet the needs of the ACS. This voluntary, peer review program had to be timely and cost effective. It was determined that the best way to address these needs would be to conduct the program by mail. Finally, by placing emphasis on the educational nature of the program, it would provide an even greater opportunity for improving mammographic quality. The result of this effort was that, almost six years ago, in May 1987, the pilot study for the ACR Mammography Accreditation Program (MAP) began, and in August of that year, the first applications were received. In November 1987, the first 3-year accreditation certificates were awarded.

Mammography accreditation program

International Nuclear Information System (INIS)

Wilcox, P.

1993-01-01

In the mid-1980's, the movement toward the use of dedicated mammography equipment provided significant improvement in breast cancer detection. However, several studies demonstrated that this change was not sufficient to ensure optimal image quality at a low radiation dose. In particular, the 1985 Nationwide Evaluation of X-ray Trends identified the wide variations in image quality and radiation dose, even from dedicated units. During this time period, the American Cancer Society (ACS) launched its Breast Cancer Awareness Screening Campaign. However, there were concerns about the ability of radiology to respond to the increased demand for optimal screening examinations that would result from the ACS program. To respond to these concerns, the ACS and the American College of Radiology (ACR) established a joint committee on mammography screening in 1986. After much discussion, it was decided to use the ACR Diagnostic Practice Accreditation Program as a model for the development of a mammography accreditation program. However, some constraints were required in order to make the program meet the needs of the ACS. This voluntary, peer review program had to be timely and cost effective. It was determined that the best way to address these needs would be to conduct the program by mail. Finally, by placing emphasis on the educational nature of the program, it would provide an even greater opportunity for improving mammographic quality. The result of this effort was that, almost six years ago, in May 1987, the pilot study for the ACR Mammography Accreditation Program (MAP) began, and in August of that year, the first applications were received. In November 1987, the first 3-year accreditation certificates were awarded

Potential Use of American College of Radiology BI-RADS Mammography Atlas for Reporting and Assessing Lesions Detected on Dedicated Breast CT Imaging: Preliminary Study.

Science.gov (United States)

Jung, Hae Kyoung; Kuzmiak, Cherie M; Kim, Keum Won; Choi, Na Mi; Kim, Hye Jeong; Langman, Eun Lee; Yoon, Sora; Steen, Doreen; Zeng, Donglin; Gao, Fei

2017-11-01

Dedicated breast computed tomography (DBCT) is an emerging and promising modality for breast lesions. The objective of this study was to evaluate the potential use of applying the BI-RADS Mammography Atlas 5th Edition for reporting and assessing breast lesions on DBCT. Currently, no atlas exists for DBCT. Four radiologists trained in breast imaging were recruited in this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study. The enrolled radiologists, who were blinded to mammographic and histopathologic findings, individually reviewed 30 randomized DBCT cases that contained marked lesions. Thirty-four lesions were included in this study: 24 (70.6%) masses, 7 (20.6%) calcifications, and 3 (8.8%) architectural distortions. Eight (23.5%) lesions were malignant and 26 (76.5%) were benign. The reader was asked to specify according to the BI-RADS Mammography Atlas for each marked DBCT lesion: primary findings, features, breast density, and final assessment. We calculated readers' diagnostic performances for differentiating between benign and malignant lesions and interobserver variability for reporting and assessing lesions using a generalized estimating equation and the Fleiss kappa (κ) statistic. The estimated overall sensitivity of the readers was 0.969, and the specificity was 0.529. There were no significant differences in the sensitivity and the specificity between lesion types. For reporting the presence of a primary finding, the overall substantial agreement (κ = 0.70) was seen. In assigning the breast density and the final assessment, the overall agreement was moderate (κ = 0.53) and fair (κ = 0.30). The use of the BI-RADS Mammography Atlas 5th Edition for DBCT showed high performance and good agreement among readers. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Radiographic techniques for digital mammography

International Nuclear Information System (INIS)

Horita, Katsuhei

2007-01-01

Since the differences in X-ray absorption between various breast tissues are small, a dedicated X-ray system for examination of the breast and a high-contrast, high-resolution screen/film system (SFM) (light-receiving system) are employed for X-ray diagnosis. Currently, however, there is a strong trend toward digital imaging in the field of general radiography, and this trend is also reflected in the field of mammographic examination. In fact, approximately 70% of facilities purchasing new mammography systems are now selecting a digital mammography system (DRM). Given this situation, this report reviews the differences between SFM and DRM and discusses the radiographic techniques and quality assurance procedures for digital mammography. (author)

Comparison of low-contrast detectability of computed radiography and screen/ film mammography systems

International Nuclear Information System (INIS)

Noriah Jamal; Kwan-Hoong Ng; McLean, D.; McLean, D.

2008-01-01

The objective of this study is to compare low-contrast detectability of computed radiography (CR) and screen/ film (SF) mammography systems. The Nijimegen contrast detail test object (CDMAM type 3.4) was imaged at 28 kV, in automatic exposure control mode separately. Six medical imaging physicists read each CDMAM phantom image. Contrast detail curves were plotted to compare low-contrast detectability of CR (soft copy and hard copy) and SF mammography systems. Effect of varying exposure parameters, namely kV, object position inside the breast phantom, and entrance surface exposure (ESE) on the contrast detail curve were also investigated using soft copy CR. The significance of the difference in contrast between CR and SF, and for each exposure parameter, was tested using non-parametric Kruskal-Wallis test. The low-contrast detectability of the CR (soft copy and hard copy) system was found to be not significantly different to that of the SF system (p> 0.05, Kruskal-Wallis test).For CR soft copy, no significant relationship (p>0.05, Kruskal-Wallis test) was seen for variation of kV, object position inside the breast phantom and ESE. This indicates that CR is comparable with SF for useful detection and visualization of low-contrast objects such as small low-contrast areas corresponding to breast pathology. (Author)

The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening: a systematic review.

Science.gov (United States)

Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm; Nielsen, Michael B; Lauridsen, Carsten A

2018-01-01

Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences in sensitivity and CDR. Adding CAD to SR increased the RR and decreased the specificity in all but one study. For the DR vs. SR + CAD group only one study reported a significant difference in RR. Conclusion All but two studies showed an increase in RR, sensitivity and CDR when adding CAD to SR. Compared to DR no statistically significant differences in sensitivity or CDR were reported. Additional studies based on organized population-based screening programs, with longer follow-up time, high-volume readers, and digital mammography are needed to evaluate the efficacy of CAD.

Radiology Residents' Performance in Screening Mammography Interpretation

International Nuclear Information System (INIS)

Lee, Eun Hye; Lyou, Chae Yeon

2013-01-01

To evaluate radiology residents' performance in screening mammography interpretation and to analyze the factors affecting performance. We enrolled 203 residents from 21 institutions and performed mammography interpretation tests. Between the trainee and non-trainee groups, we compared the interpretation score, recall rate, sensitivity, positive predictive value (PPV) and false-positive rate (FPR). We estimated the training effect using the score differences between trainee and non-trainee groups. We analyzed the factors affecting performance between training-effective and non-effective groups. Trainees were superior to non-trainees regarding interpretation score (43.1 vs. 37.1), recall rate (11.0 vs. 15.5%), sensitivity (83.6 vs. 72.0%), PPV (53.0 vs. 32.4%) and FPR (13.5 vs. 25.5). The longer the training period, the better were the interpretation score, recall rate, sensitivity, PPV and FPR (rho = 0.486, -0.375, 0.343, 0.504, -0.446, respectively). The training affected an increase by an average of 6 points; however, 31.6% of institutions showed no effect. A difference was noted in the volume of mammography interpretation during a month (594.0 vs. 476.9) and dedication of breast staff (61.5 vs. 0%) between training-effective and non-effective groups. Trainees showed better performance in mammography interpretation compared to non-trainees. Moreover, performance was correlated with the training period. The factors affecting performance were the volume of mammography interpretation and the dedication of the breast staff.

Computer-Assisted Visual Search/Decision Aids as a Training Tool for Mammography

National Research Council Canada - National Science Library

Nodine, Calvin

1999-01-01

The primary goal of the project is to develop a computer-assisted visual search (CAVS) mammography training tool that will improve the perceptual and cognitive skills of trainees leading to mammographic expertise...

Computer-Assisted Visual Search/Decision Aids as a Training Tool for Mammography

National Research Council Canada - National Science Library

Nodine, Calvin

1998-01-01

The primary goal of the project is to develop a computer-assisted visual search (CAVS) mammography training tool that will improve the perceptual and cognitive skills of trainees leading to mammographic expertise...

Computer-Assisted Visual Search/Decision Aids as a Training Tool for Mammography

National Research Council Canada - National Science Library

Nodine, Calvin

2000-01-01

The primary goal of the project is to develop a computer-assisted visual search (CAVS) mammography training tool that will improve the perceptual and cognitive skills of trainees leading to mammographic expertise...

A computer simulation study comparing lesion detection accuracy with digital mammography, breast tomosynthesis, and cone-beam CT breast imaging

International Nuclear Information System (INIS)

Gong Xing; Glick, Stephen J.; Liu, Bob; Vedula, Aruna A.; Thacker, Samta

2006-01-01

Although conventional mammography is currently the best modality to detect early breast cancer, it is limited in that the recorded image represents the superposition of a three-dimensional (3D) object onto a 2D plane. Recently, two promising approaches for 3D volumetric breast imaging have been proposed, breast tomosynthesis (BT) and CT breast imaging (CTBI). To investigate possible improvements in lesion detection accuracy with either breast tomosynthesis or CT breast imaging as compared to digital mammography (DM), a computer simulation study was conducted using simulated lesions embedded into a structured 3D breast model. The computer simulation realistically modeled x-ray transport through a breast model, as well as the signal and noise propagation through a CsI based flat-panel imager. Polyenergetic x-ray spectra of Mo/Mo 28 kVp for digital mammography, Mo/Rh 28 kVp for BT, and W/Ce 50 kVp for CTBI were modeled. For the CTBI simulation, the intensity of the x-ray spectra for each projection view was determined so as to provide a total average glandular dose of 4 mGy, which is approximately equivalent to that given in conventional two-view screening mammography. The same total dose was modeled for both the DM and BT simulations. Irregular lesions were simulated by using a stochastic growth algorithm providing lesions with an effective diameter of 5 mm. Breast tissue was simulated by generating an ensemble of backgrounds with a power law spectrum, with the composition of 50% fibroglandular and 50% adipose tissue. To evaluate lesion detection accuracy, a receiver operating characteristic (ROC) study was performed with five observers reading an ensemble of images for each case. The average area under the ROC curves (A z ) was 0.76 for DM, 0.93 for BT, and 0.94 for CTBI. Results indicated that for the same dose, a 5 mm lesion embedded in a structured breast phantom was detected by the two volumetric breast imaging systems, BT and CTBI, with statistically

Needs assessment for next generation computer-aided mammography reference image databases and evaluation studies.

Science.gov (United States)

Horsch, Alexander; Hapfelmeier, Alexander; Elter, Matthias

2011-11-01

Breast cancer is globally a major threat for women's health. Screening and adequate follow-up can significantly reduce the mortality from breast cancer. Human second reading of screening mammograms can increase breast cancer detection rates, whereas this has not been proven for current computer-aided detection systems as "second reader". Critical factors include the detection accuracy of the systems and the screening experience and training of the radiologist with the system. When assessing the performance of systems and system components, the choice of evaluation methods is particularly critical. Core assets herein are reference image databases and statistical methods. We have analyzed characteristics and usage of the currently largest publicly available mammography database, the Digital Database for Screening Mammography (DDSM) from the University of South Florida, in literature indexed in Medline, IEEE Xplore, SpringerLink, and SPIE, with respect to type of computer-aided diagnosis (CAD) (detection, CADe, or diagnostics, CADx), selection of database subsets, choice of evaluation method, and quality of descriptions. 59 publications presenting 106 evaluation studies met our selection criteria. In 54 studies (50.9%), the selection of test items (cases, images, regions of interest) extracted from the DDSM was not reproducible. Only 2 CADx studies, not any CADe studies, used the entire DDSM. The number of test items varies from 100 to 6000. Different statistical evaluation methods are chosen. Most common are train/test (34.9% of the studies), leave-one-out (23.6%), and N-fold cross-validation (18.9%). Database-related terminology tends to be imprecise or ambiguous, especially regarding the term "case". Overall, both the use of the DDSM as data source for evaluation of mammography CAD systems, and the application of statistical evaluation methods were found highly diverse. Results reported from different studies are therefore hardly comparable. Drawbacks of the DDSM

Contrast-enhanced dedicated breast CT detection of invasive breast cancer preceding mammographic diagnosis

Directory of Open Access Journals (Sweden)

Nicolas D. Prionas, MD, PhD

2015-01-01

Full Text Available Dedicated breast computed tomography (bCT generates high-resolution, three-dimensional images of the pendent uncompressed breast. Intravenous iodinated contrast during bCT provides additional physiologic information. In this case, a 10.0-mm invasive ductal carcinoma was visualized using contrast-enhanced breast CT one year before mammographic detection. Mammography four months before bCT was negative. The bCT contrast enhancement pattern closely matched the dynamic contrast-enhanced MRI obtained after diagnosis. Lesion enhancement at contrast-enhanced breast CT matched previously published enhancement values of breast cancer. Contrast-enhanced dedicated bCT provided high-resolution tomographic images and physiologic contrast enhancement data that facilitated the detection of an early breast cancer.

Lesion detection and quantitation of positron emission mammography

International Nuclear Information System (INIS)

Qi, Jinyi; Huesman, Ronald H.

2001-01-01

A Positron Emission Mammography (PEM) scanner dedicated to breast imaging is being developed at our laboratory. We have developed a list mode likelihood reconstruction algorithm for this scanner. Here we theoretically study the lesion detection and quantitation. The lesion detectability is studied theoretically using computer observers. We found that for the zero-order quadratic prior, the region of interest observer can achieve the performance of the prewhitening observer with a properly selected smoothing parameter. We also study the lesion quantitation using the test statistic of the region of interest observer. The theoretical expressions for the bias, variance, and ensemble mean squared error of the quantitation are derived. Computer simulations show that the theoretical predictions are in good agreement with the Monte Carlo results for both lesion detection and quantitation

Thermoluminescence dosimetry in quality imaging in CR mammography systems

Energy Technology Data Exchange (ETDEWEB)

Gaona, E.; Franco E, J.G. [UAM-Xochimilco, 04960 Mexico D.F. (Mexico); Azorin N, J. [UAM-Iztapalapa, 09340 Mexico D.F. (Mexico); Diaz G, J.A.I. [CICATA, Unidad Legaria, Av. Legaria 694, 11599 mexico D.F. (Mexico); Arreola, M. [Department of Radiology, Shands Hospital at UF, PO Box 100374, Gainesville, FL 32610-0374 (United States)

2006-07-01

The aim of this work is to estimate the average glandular dose with Thermoluminescence Dosimetry (TLD) and comparison with quality imaging in CR mammography. For measuring dose, FDA and ACR use a phantom, so that dose and image quality are assessed with the same test object. The mammography is a radiological image to visualize early biological manifestations of breast cancer. Digital systems have two types of image-capturing devices, Full Field Digital Mammography (FFDM) and CR mammography. In Mexico, there are several CR mammography systems in clinical use, but only one CR mammography system has been approved for use by the FDA. Mammography CR uses a photostimulable phosphor detector (PSP) system. Most CR plates are made of 85% BaFBr and 15% BaFI doped with europium (Eu) commonly called barium fluoro halide. We carry out an exploratory survey of six CR mammography units from three different manufacturers and six dedicated x-ray mammography units with fully automatic exposure. The results show three CR mammography units (50%) have a dose that overcomes 3.0 mGy and it doesn't improve the image quality and dose to the breast will be excessive. The differences between doses averages from TLD system and dosimeter with ionization chamber are less than 10%. TLD system is a good option for average glandular dose measurement. (Author)

Thermoluminescence dosimetry in quality imaging in CR mammography systems

International Nuclear Information System (INIS)

Gaona, E.; Franco E, J.G.; Azorin N, J.; Diaz G, J.A.I.; Arreola, M.

2006-01-01

The aim of this work is to estimate the average glandular dose with Thermoluminescence Dosimetry (TLD) and comparison with quality imaging in CR mammography. For measuring dose, FDA and ACR use a phantom, so that dose and image quality are assessed with the same test object. The mammography is a radiological image to visualize early biological manifestations of breast cancer. Digital systems have two types of image-capturing devices, Full Field Digital Mammography (FFDM) and CR mammography. In Mexico, there are several CR mammography systems in clinical use, but only one CR mammography system has been approved for use by the FDA. Mammography CR uses a photostimulable phosphor detector (PSP) system. Most CR plates are made of 85% BaFBr and 15% BaFI doped with europium (Eu) commonly called barium fluoro halide. We carry out an exploratory survey of six CR mammography units from three different manufacturers and six dedicated x-ray mammography units with fully automatic exposure. The results show three CR mammography units (50%) have a dose that overcomes 3.0 mGy and it doesn't improve the image quality and dose to the breast will be excessive. The differences between doses averages from TLD system and dosimeter with ionization chamber are less than 10%. TLD system is a good option for average glandular dose measurement. (Author)

Organisational aspects of mammography screening in digital settings: First experiences of Luxembourg

International Nuclear Information System (INIS)

Shannoun, F.; Schanck, J. M.; Scharpantgen, A.; Wagnon, M. C.; Ben Daoud, M.; Back, C.

2008-01-01

Luxembourg has been conducting a breast cancer screening programme since 1992, like a large number of other European countries, as early detection and treatment of breast cancer have been proven to reduce mortality. The majority of these screening programmes are based on analogue X-ray technology and have optimised their organisation of transporting, archiving and reading with respect to films. Last decade is marked by enormous developments in digital mammography. Different technologies such as flat panel-, computed radiography- and scanning systems became available. Digital mammography is expected to have a major impact on quality and organisation of breast cancer screening programmes. Screening programmes are now faced with a huge challenge of incorporating the digital technology, including implementation of electronic image exchange, conception of new electronic work-flow, establishing adapted quality assurance programmes and training of radiologists and technical personnel. Initial experiences of the Luxembourg approach in organising digital mammography screening and its quality assurance are reported. (authors)

Comparison of digital mammography alone and digital mammography plus tomosynthesis in a population-based screening program.

Science.gov (United States)

Skaane, Per; Bandos, Andriy I; Gullien, Randi; Eben, Ellen B; Ekseth, Ulrika; Haakenaasen, Unni; Izadi, Mina; Jebsen, Ingvild N; Jahr, Gunnar; Krager, Mona; Niklason, Loren T; Hofvind, Solveig; Gur, David

2013-04-01

To assess cancer detection rates, false-positive rates before arbitration, positive predictive values for women recalled after arbitration, and the type of cancers detected with use of digital mammography alone and combined with tomosynthesis in a large prospective screening trial. A prospective, reader- and modality-balanced screening study of participants undergoing combined mammography plus tomosynthesis, the results of which were read independently by four different radiologists, is under way. The study was approved by a regional ethics committee, and all participants provided written informed consent. The authors performed a preplanned interim analysis of results from 12,631 examinations interpreted by using mammography alone and mammography plus tomosynthesis from November 22, 2010, to December 31, 2011. Analyses were based on marginal log-linear models for binary data, accounting for correlated interpretations and adjusting for reader-specific performance levels by using a two-sided significance level of .0294. Detection rates, including those for invasive and in situ cancers, were 6.1 per 1000 examinations for mammography alone and 8.0 per 1000 examinations for mammography plus tomosynthesis (27% increase, adjusted for reader; P = .001). False-positive rates before arbitration were 61.1 per 1000 examinations with mammography alone and 53.1 per 1000 examinations with mammography plus tomosynthesis (15% decrease, adjusted for reader; P tomosynthesis; P = .72). Twenty-five additional invasive cancers were detected with mammography plus tomosynthesis (40% increase, adjusted for reader; P tomosynthesis (P tomosynthesis in a screening environment resulted in a significantly higher cancer detection rate and enabled the detection of more invasive cancers. Clinical trial registration no. NCT01248546. RSNA, 2013

Follow-up and Final Results of the Oslo I Study Comparing Screen-Film Mammography and Full-field Digital Mammography with Soft-Copy Reading

International Nuclear Information System (INIS)

Skaane, P.; Skjennald, A.; Young, K.

2005-01-01

Purpose: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. Material and Methods: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. Results: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P 0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P = 0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A

Follow-up and Final Results of the Oslo I Study Comparing Screen-Film Mammography and Full-field Digital Mammography with Soft-Copy Reading

Energy Technology Data Exchange (ETDEWEB)

Skaane, P.; Skjennald, A.; Young, K. [Ullevaal Univ. Hospital, Oslo (Norway). Dept. of Radiology] [and others

2005-11-01

Purpose: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. Material and Methods: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. Results: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P 0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P = 0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A

Optical Design Using Small Dedicated Computers

Science.gov (United States)

Sinclair, Douglas C.

1980-09-01

Since the time of the 1975 International Lens Design Conference, we have developed a series of optical design programs for Hewlett-Packard desktop computers. The latest programs in the series, OSLO-25G and OSLO-45G, have most of the capabilities of general-purpose optical design programs, including optimization based on exact ray-trace data. The computational techniques used in the programs are similar to ones used in other programs, but the creative environment experienced by a designer working directly with these small dedicated systems is typically much different from that obtained with shared-computer systems. Some of the differences are due to the psychological factors associated with using a system having zero running cost, while others are due to the design of the program, which emphasizes graphical output and ease of use, as opposed to computational speed.

Initial Reading through Computer Animation.

Science.gov (United States)

Geoffrion, Leo D.; Bergeron, R. Daniel

The Computer Animated Reading Instruction System (CARIS) was developed to introduce reading to children with varied sensory, cognitive, and physical handicaps. CARIS employs an exploratory learning approach which encourages children to experiment with the reading and writing of words and sentences. Brief computer-animated cartoons provide the…

Fusion of dynamic contrast-enhanced magnetic resonance mammography at 3.0 T with X-ray mammograms: Pilot study evaluation using dedicated semi-automatic registration software

Energy Technology Data Exchange (ETDEWEB)

Dietzel, Matthias, E-mail: dietzelmatthias2@hotmail.com [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07740 Jena (Germany); Hopp, Torsten; Ruiter, Nicole [Karlsruhe Institute of Technology (KIT), Institute for Data Processing and Electronics, Postfach 3640, D-76021 Karlsruhe (Germany); Zoubi, Ramy [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07740 Jena (Germany); Runnebaum, Ingo B. [Clinic of Gynecology and Obstetrics, Friedrich-Schiller-University Jena, Bachstrasse 18, D-07743 Jena (Germany); Kaiser, Werner A. [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07740 Jena (Germany); Medical School, University of Harvard, 25 Shattuck Street, Boston, MA 02115 (United States); Baltzer, Pascal A.T. [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07740 Jena (Germany)

2011-08-15

Rationale and objectives: To evaluate the semi-automatic image registration accuracy of X-ray-mammography (XR-M) with high-resolution high-field (3.0 T) MR-mammography (MR-M) in an initial pilot study. Material and methods: MR-M was acquired on a high-field clinical scanner at 3.0 T (T1-weighted 3D VIBE {+-} Gd). XR-M was obtained with state-of-the-art full-field digital systems. Seven patients with clearly delineable mass lesions >10 mm both in XR-M and MR-M were enrolled (exclusion criteria: previous breast surgery; surgical intervention between XR-M and MR-M). XR-M and MR-M were matched using a dedicated image-registration algorithm allowing semi-automatic non-linear deformation of MR-M based on finite-element modeling. To identify registration errors (RE) a virtual craniocaudal 2D mammogram was calculated by the software from MR-M (with and w/o Gadodiamide/Gd) and matched with corresponding XR-M. To quantify REs the geometric center of the lesions in the virtual vs. conventional mammogram were subtracted. The robustness of registration was quantified by registration of X-MRs to both MR-Ms with and w/o Gadodiamide. Results: Image registration was performed successfully for all patients. Overall RE was 8.2 mm (1 min after Gd; confidence interval/CI: 2.0-14.4 mm, standard deviation/SD: 6.7 mm) vs. 8.9 mm (no Gd; CI: 4.0-13.9 mm, SD: 5.4 mm). The mean difference between pre- vs. post-contrast was 0.7 mm (SD: 1.9 mm). Conclusion: Image registration of high-field 3.0 T MR-mammography with X-ray-mammography is feasible. For this study applying a high-resolution protocol at 3.0 T, the registration was robust and the overall registration error was sufficient for clinical application.

Fusion of dynamic contrast-enhanced magnetic resonance mammography at 3.0 T with X-ray mammograms: Pilot study evaluation using dedicated semi-automatic registration software

International Nuclear Information System (INIS)

Dietzel, Matthias; Hopp, Torsten; Ruiter, Nicole; Zoubi, Ramy; Runnebaum, Ingo B.; Kaiser, Werner A.; Baltzer, Pascal A.T.

2011-01-01

Rationale and objectives: To evaluate the semi-automatic image registration accuracy of X-ray-mammography (XR-M) with high-resolution high-field (3.0 T) MR-mammography (MR-M) in an initial pilot study. Material and methods: MR-M was acquired on a high-field clinical scanner at 3.0 T (T1-weighted 3D VIBE ± Gd). XR-M was obtained with state-of-the-art full-field digital systems. Seven patients with clearly delineable mass lesions >10 mm both in XR-M and MR-M were enrolled (exclusion criteria: previous breast surgery; surgical intervention between XR-M and MR-M). XR-M and MR-M were matched using a dedicated image-registration algorithm allowing semi-automatic non-linear deformation of MR-M based on finite-element modeling. To identify registration errors (RE) a virtual craniocaudal 2D mammogram was calculated by the software from MR-M (with and w/o Gadodiamide/Gd) and matched with corresponding XR-M. To quantify REs the geometric center of the lesions in the virtual vs. conventional mammogram were subtracted. The robustness of registration was quantified by registration of X-MRs to both MR-Ms with and w/o Gadodiamide. Results: Image registration was performed successfully for all patients. Overall RE was 8.2 mm (1 min after Gd; confidence interval/CI: 2.0-14.4 mm, standard deviation/SD: 6.7 mm) vs. 8.9 mm (no Gd; CI: 4.0-13.9 mm, SD: 5.4 mm). The mean difference between pre- vs. post-contrast was 0.7 mm (SD: 1.9 mm). Conclusion: Image registration of high-field 3.0 T MR-mammography with X-ray-mammography is feasible. For this study applying a high-resolution protocol at 3.0 T, the registration was robust and the overall registration error was sufficient for clinical application.

Influence of age and menstrual cycle on mammography and MR imaging of the breast; Einfluss von Alter und Menstruationszyklus auf Mammographie und MR-Mammographie

Energy Technology Data Exchange (ETDEWEB)

Mueller-Schimpfle, M.; Ohmenhaeuser, K.; Claussen, C.D. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik

1997-09-01

Age and menstrual cycle have an important influence on the breast. This well-known fact is experienced in the daily routine of gynecologists and radiologists. The number of publications addressing the effect of these influences on imaging, however, is surprisingly low. The aim of this work is to describe the influences of age and menstrual cycle on the breast and to address their clinical relevance for mammography and MR mammography. Therefore, own data are presented concerning the age and menstrual cycle influences on breast parenchyma in dynamic MR mammography. Literature data are used to correlate mammography and MR imaging findings with these influences. The changes of the breast due to age and menstrual cycle have important direct implications on performing and reading conventional mammography and MR mammography. The knowledge of these changes is also helpful in the interpretation of findings when comparing different methods. Finally, the data gained by using imaging methods enable important basic insights into physiology and physiopathology of the breast in vivo. (orig.) [Deutsch] Alter und Menstruationszyklus stellen wichtige Einflussfaktoren auf die Mamma dar. Diese Tatsache ist klinisch lange bekannt und im Alltag des Gynaekologen wie Radiologen staendig praesent. Dagegen ist die Anzahl der Publikationen zu den Auswirkungen dieser Einfluesse auf die Bildgebung erstaunlich niedrig. Ziel dieser Arbeit ist es, die alters- und zyklusabhaengigen Veraenderungen der Mamma und deren klinische Relevanz fuer die Mammographie und MR-Mammographie darzustellen. Zu diesem Zweck werden aus einer eigenen Studie Daten der dynamischen MR-Tomographie zum Alters- und Zykluseinfluss auf das Mammaparenchym praesentiert. Darueber hinaus werden diese Einflussfaktoren mit mammographischen und MR-tomographischen Daten aus der Literatur korreliert. Dabei zeigt sich, dass sich aus den alters- und menstruationszyklusbedingten Veraenderungen der Brust wichtige unmittelbare

Interobserver agreement and performance score comparison in quality control using a breast phantom: screen-film mammography vs computed radiography

International Nuclear Information System (INIS)

Shimamoto, Kazuhiro; Ikeda, Mitsuru; Satake, Hiroko; Ishigaki, Satoko; Sawaki, Akiko; Ishigaki, Takeo

2002-01-01

Our objective was to evaluate interobserver agreement and to compare the performance score in quality control of screen-film mammography and computed radiography (CR) using a breast phantom. Eleven radiologists interpreted a breast phantom image (CIRS model X) by four viewing methods: (a) original screen-film; (b) soft-copy reading of the digitized film image; (c) hard-copy reading of CR using an imaging plate; and (d) soft-copy reading of CR. For the soft-copy reading, a 17-in. CRT monitor (1024 x 1536 x 8 bits) was used. The phantom image was evaluated using a scoring system outlined in the instruction manual, and observers judged each object using a three-point rating scale: (a) clearly seen; (b) barely seen; and (c) not seen. For statistical analysis, the kappa statistic was employed. For ''mass'' depiction, interobserver agreement using CR was significantly lower than when using screen-film (p<0.05). There was no significant difference in the kappa value for detecting ''microcalcification''; however, the performance score of ''microcalcification'' on CR hard-copy was significantly lower than on the other three viewing methods (p<0.05). Viewing methods (film or CR, soft-copy or hard-copy) could affect how the phantom image is judged. Paying special attention to viewing conditions is recommended for quality control of CR mammograms. (orig.)

Added value of one-view breast tomosynthesis combined with digital mammography according to reader experience.

Science.gov (United States)

Thomassin-Naggara, Isabelle; Perrot, Nicolas; Dechoux, Sophie; Ribeiro, Carine; Chopier, Jocelyne; de Bazelaire, Cedric

2015-02-01

To retrospectively evaluate the added value of one-view breast tomosynthesis in adjunct with mammography to characterize breast lesions. Our institutional ethics committees approved the study and granted a waiver of informed consent. One hundred fifty-five women (mean age, 51.3 years, range: 24-92 years) who systematically underwent mammography and breast tomosynthesis with subsequent percutaneous biopsy were analyzed. Four radiologists (two seniors, R1 and R2, and two juniors, R3 and R4 with 30, 10, 3 and 1 years of experience in breast imaging, respectively) independently reviewed exams in two steps: mammography alone and tomosynthesis in adjunct with mammography. The lesions in the cohort included 39.3% (61/155) cancers, 2.5% (4/155) high-risk lesions and 58.1% (90/155) benign lesions. A receiver operating characteristic (ROC) curve analysis was performed to compare the results of the two readings. There was almost perfect agreement irrespective of reader experience for the reading of the mammography in adjunct with tomosynthesis, whereas agreement was poor between junior and senior readers for the reading of mammography alone. Area under the ROC (Az) values for the tomosynthesis in adjunct with mammography were significantly better than Az values for mammography alone for all readers except the most experienced, for whom only a tendency was noted. The proportion of cancers undiagnosed by mammography alone that were well diagnosed by tomosynthesis in adjunct with mammography was 6.5% (4/61), 13.1% (8/61), 27.8% (17/61) and 26.2% (16/61) for Readers 1, 2, 3 and 4, respectively. The proportion of false positive cases induced by the addition of breast tomosynthesis to mammography was 2.1% (2/94), 2.1% (2/94), 9.5% (9/94) and 12.7% (12/94) for Readers 1, 2, 3 and 4, respectively. Adding breast tomosynthesis to mammography improved sensitivity and negative predictive value for all readers except for the most experienced one, in whom only a tendency for improvement

Is computer aided detection (CAD) cost effective in screening mammography? A model based on the CADET II study

Science.gov (United States)

2011-01-01

Background Single reading with computer aided detection (CAD) is an alternative to double reading for detecting cancer in screening mammograms. The aim of this study is to investigate whether the use of a single reader with CAD is more cost-effective than double reading. Methods Based on data from the CADET II study, the cost-effectiveness of single reading with CAD versus double reading was measured in terms of cost per cancer detected. Cost (Pound (£), year 2007/08) of single reading with CAD versus double reading was estimated assuming a health and social service perspective and a 7 year time horizon. As the equipment cost varies according to the unit size a separate analysis was conducted for high, average and low volume screening units. One-way sensitivity analyses were performed by varying the reading time, equipment and assessment cost, recall rate and reader qualification. Results CAD is cost increasing for all sizes of screening unit. The introduction of CAD is cost-increasing compared to double reading because the cost of CAD equipment, staff training and the higher assessment cost associated with CAD are greater than the saving in reading costs. The introduction of single reading with CAD, in place of double reading, would produce an additional cost of £227 and £253 per 1,000 women screened in high and average volume units respectively. In low volume screening units, the high cost of purchasing the equipment will results in an additional cost of £590 per 1,000 women screened. One-way sensitivity analysis showed that the factors having the greatest effect on the cost-effectiveness of CAD with single reading compared with double reading were the reading time and the reader's professional qualification (radiologist versus advanced practitioner). Conclusions Without improvements in CAD effectiveness (e.g. a decrease in the recall rate) CAD is unlikely to be a cost effective alternative to double reading for mammography screening in UK. This study

The efficacy of using CAD for detection of breast cancer in mammography screening A systematic review

DEFF Research Database (Denmark)

Henriksen, Emilie; Lauridsen, Carsten Ammitzbøl

Abstract Purpose: The aim of this systematic review is to present an overview of the available studies concerning the use of computer-aided detection (CAD) systems in screening mammography for early detection of breast cancer and compare the diagnostic accuracy and recall rates of single reading....... The literature search resulted in 1522 records after duplicates were removed. 1491 records were excluded by abstract and 18 were excluded after assessing the eligibility by full text reading. A total of 13 articles were included in this study. Results: The results for the single reading vs. single reading...... with CAD group indicate that the addition of CAD increases sensitivity and cancer detection rate (CDR). For the double reading vs. single reading with CAD group none of the studies reported significant differences in sensitivity and CDR. Adding CAD to single reading increased the recall rates and decreased...

Added value of one-view breast tomosynthesis combined with digital mammography according to reader experience

International Nuclear Information System (INIS)

Thomassin-Naggara, Isabelle; Perrot, Nicolas; Dechoux, Sophie; Ribeiro, Carine; Chopier, Jocelyne; Bazelaire, Cedric de

2015-01-01

Highlights: • Breast tomosynthesis improves diagnostic performance especially for radiologists with lower experience in mammography. • Adding only one-view digital breast tomosynthesis to mammography improves the cancer detection rate. • Breast tomosynthesis is mainly useful for helping radiologists to detect architectural distortion. - Abstract: Purpose: To retrospectively evaluate the added value of one-view breast tomosynthesis in adjunct with mammography to characterize breast lesions. Materials and methods: Our institutional ethics committees approved the study and granted a waiver of informed consent. One hundred fifty-five women (mean age, 51.3 years, range: 24–92 years) who systematically underwent mammography and breast tomosynthesis with subsequent percutaneous biopsy were analyzed. Four radiologists (two seniors, R1 and R2, and two juniors, R3 and R4 with 30, 10, 3 and 1 years of experience in breast imaging, respectively) independently reviewed exams in two steps: mammography alone and tomosynthesis in adjunct with mammography. The lesions in the cohort included 39.3% (61/155) cancers, 2.5% (4/155) high-risk lesions and 58.1% (90/155) benign lesions. A receiver operating characteristic (ROC) curve analysis was performed to compare the results of the two readings. Results: There was almost perfect agreement irrespective of reader experience for the reading of the mammography in adjunct with tomosynthesis, whereas agreement was poor between junior and senior readers for the reading of mammography alone. Area under the ROC (Az) values for the tomosynthesis in adjunct with mammography were significantly better than Az values for mammography alone for all readers except the most experienced, for whom only a tendency was noted. The proportion of cancers undiagnosed by mammography alone that were well diagnosed by tomosynthesis in adjunct with mammography was 6.5% (4/61), 13.1% (8/61), 27.8% (17/61) and 26.2% (16/61) for Readers 1, 2, 3 and 4

Added value of one-view breast tomosynthesis combined with digital mammography according to reader experience

Energy Technology Data Exchange (ETDEWEB)

Thomassin-Naggara, Isabelle, E-mail: isabelle.thomassin@tnn.aphp.fr [Sorbonne Universités, UPMC Univ Paris 06, IUC, 75005 Paris (France); INSERM, UMR970, Equipe 2, Imagerie de l’angiogenèse, 75005 Paris (France); AP-HP, Hôpital Tenon, Department of Radiology, 4 rue de la Chine, 75020 Paris (France); Perrot, Nicolas [AP-HP, Hôpital Tenon, Department of Radiology, 4 rue de la Chine, 75020 Paris (France); Centre Pyramides, Paris (France); Dechoux, Sophie [Sorbonne Universités, UPMC Univ Paris 06, IUC, 75005 Paris (France); AP-HP, Hôpital Tenon, Department of Radiology, 4 rue de la Chine, 75020 Paris (France); Ribeiro, Carine [Centre Pyramides, Paris (France); Chopier, Jocelyne [AP-HP, Hôpital Tenon, Department of Radiology, 4 rue de la Chine, 75020 Paris (France); Bazelaire, Cedric de [APHP, Department of Radiology, Hôpital Saint Louis, 75010 Paris (France)

2015-02-15

Highlights: • Breast tomosynthesis improves diagnostic performance especially for radiologists with lower experience in mammography. • Adding only one-view digital breast tomosynthesis to mammography improves the cancer detection rate. • Breast tomosynthesis is mainly useful for helping radiologists to detect architectural distortion. - Abstract: Purpose: To retrospectively evaluate the added value of one-view breast tomosynthesis in adjunct with mammography to characterize breast lesions. Materials and methods: Our institutional ethics committees approved the study and granted a waiver of informed consent. One hundred fifty-five women (mean age, 51.3 years, range: 24–92 years) who systematically underwent mammography and breast tomosynthesis with subsequent percutaneous biopsy were analyzed. Four radiologists (two seniors, R1 and R2, and two juniors, R3 and R4 with 30, 10, 3 and 1 years of experience in breast imaging, respectively) independently reviewed exams in two steps: mammography alone and tomosynthesis in adjunct with mammography. The lesions in the cohort included 39.3% (61/155) cancers, 2.5% (4/155) high-risk lesions and 58.1% (90/155) benign lesions. A receiver operating characteristic (ROC) curve analysis was performed to compare the results of the two readings. Results: There was almost perfect agreement irrespective of reader experience for the reading of the mammography in adjunct with tomosynthesis, whereas agreement was poor between junior and senior readers for the reading of mammography alone. Area under the ROC (Az) values for the tomosynthesis in adjunct with mammography were significantly better than Az values for mammography alone for all readers except the most experienced, for whom only a tendency was noted. The proportion of cancers undiagnosed by mammography alone that were well diagnosed by tomosynthesis in adjunct with mammography was 6.5% (4/61), 13.1% (8/61), 27.8% (17/61) and 26.2% (16/61) for Readers 1, 2, 3 and 4

Computer Applications in Reading. Third Edition.

Science.gov (United States)

Blanchard, Jay S.; And Others

Intended as a reference for researchers, teachers, and administrators, this book chronicles research, programs, and uses of computers in reading. Chapter 1 provides a broad view of computer applications in education, while Chapter 2 provides annotated references for computer based reading and language arts programs for children and adults in…

Prospective trial comparing full-field digital mammography (FFDM) versus combined FFDM and tomosynthesis in a population-based screening programme using independent double reading with arbitration

International Nuclear Information System (INIS)

Skaane, Per; Bandos, Andriy I.; Gullien, Randi; Eben, Ellen B.; Haakenaasen, Unni; Izadi, Mina; Jebsen, Ingvild N.; Jahr, Gunnar; Krager, Mona; Ekseth, Ulrika; Hofvind, Solveig

2013-01-01

To compare double readings when interpreting full field digital mammography (2D) and tomosynthesis (3D) during mammographic screening. A prospective, Ethical Committee approved screening study is underway. During the first year 12,621 consenting women underwent both 2D and 3D imaging. Each examination was independently interpreted by four radiologists under four reading modes: Arm A - 2D; Arm B - 2D + CAD; Arm C - 2D + 3D; Arm D - synthesised 2D + 3D. Examinations with a positive score by at least one reader were discussed at an arbitration meeting before a final management decision. Paired double reading of 2D (Arm A + B) and 2D + 3D (Arm C + D) were analysed. Performance measures were compared using generalised linear mixed models, accounting for inter-reader performance heterogeneity (P < 0.05). Pre-arbitration false-positive scores were 10.3 % (1,286/12,501) and 8.5 % (1,057/12,501) for 2D and 2D + 3D, respectively (P < 0.001). Recall rates were 2.9 % (365/12,621) and 3.7 % (463/12,621), respectively (P = 0.005). Cancer detection was 7.1 (90/12,621) and 9.4 (119/12,621) per 1,000 examinations, respectively (30 % increase, P < 0.001); positive predictive values (detected cancer patients per 100 recalls) were 24.7 % and 25.5 %, respectively (P = 0.97). Using 2D + 3D, double-reading radiologists detected 27 additional invasive cancers (P < 0.001). Double reading of 2D + 3D significantly improves the cancer detection rate in mammography screening. (orig.)

Impact on breast cancer diagnosis in a multidisciplinary unit after the incorporation of mammography digitalization and computer-aided detection systems.

Science.gov (United States)

Romero, Cristina; Varela, Celia; Muñoz, Enriqueta; Almenar, Asunción; Pinto, Jose María; Botella, Miguel

2011-12-01

The purpose of this article is to evaluate the impact on the diagnosis of breast cancer of implementing full-field digital mammography (FFDM) in a multidisciplinary breast pathology unit and, 1 year later, the addition of a computer-aided detection (CAD) system. A total of 13,453 mammograms performed between January and July of the years 2004, 2006, and 2007 were retrospectively reviewed using conventional mammography, digital mammography, and digital mammography plus CAD techniques. Mammograms were classified into two subsets: screening and diagnosis. Variables analyzed included cancer detection rate, rate of in situ carcinoma, tumor size at detection, biopsy rate, and positive predictive value of biopsy. FFDM increased the cancer detection rate, albeit not statistically significantly. The detection rate of in situ carcinoma increased significantly using FFDM plus CAD compared with conventional technique (36.8% vs 6.7%; p = 0.05 without Bonferroni statistical correction) for the screening dataset. Relative to conventional mammography, tumor size at detection decreased with digital mammography (T1, 61.5% vs 88%; p = 0.018) and with digital mammography plus CAD (T1, 79.7%; p = 0.03 without Bonferroni statistical correction). Biopsy rates in the general population increased significantly using CAD (10.6/1000 for conventional mammography, 14.7/1000 for digital mammography, and 17.9/1000 for digital mammography plus CAD; p = 0.02). The positive predictive value of biopsy decreased slightly, but not significantly, for both subsets. The incorporation of new techniques has improved the performance of the breast unit by increasing the overall detection rates and earlier detection (smaller tumors), both leading to an increase in interventionism.

Readability assessment of internet-based patient education materials related to mammography for breast cancer screening.

Science.gov (United States)

AlKhalili, Rend; Shukla, Pratik A; Patel, Ronak H; Sanghvi, Saurin; Hubbi, Basil

2015-03-01

The US Department of Health and Human Services (USDHHS) recommends that Internet-based patient education materials (IPEMs) be written below the sixth-grade reading level to target the average American adult. This study was designed to determine the readability of IPEMs regarding mammography for breast cancer screening. Three-hundred mammography-related Web sites were reviewed for IPEMs. Forty-two IPEMs that met the Health on the Net Foundation Code of Conduct were assessed for readability level with four readability indices that use existing algorithms based on word and sentence length to quantitatively analyze Internet sources for language intricacy including the following: Flesch-Kincaid Grade Level (FKGL), Flesch Reading Ease Score (FRES), Simple Measure of Gobbledygook (SMOG), and Gunning Frequency of Gobbledygook (Gunning FOG; GFOG). Results were compared to national recommendations, and intergroup analysis was performed. No IPEMs (0%) regarding mammography were written at or below the sixth-grade reading level, based on FKGL. The mean readability scores were as follows: FRES, 49.04 ± 10.62; FKGL, 10.71 ± 2.01; SMOG, 13.33 ± 1.67; and Gunning FOG, 14.32 ± 2.18. These scores indicate that the readability of mammography IPEMs is written at a "difficult" level, significantly above the recommended sixth-grade reading level (P < .05) determined by the USDHHS. IPEMs related to mammography are written well above the recommended sixth-grade level and likely reflect other IPEMs in diagnostic radiology. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

TU-EF-207-05: Dedicated Cone-beam Breast CT

International Nuclear Information System (INIS)

Vedantham, S.

2015-01-01

mode due to lower photon fluence per projection. This may require fast-frame acquisition and symmetric or asymmetric pixel binning in some systems. Recent studies investigated the performance of increased conversion layer thickness for contrast-enhanced imaging of the breast in dual-energy acquisition mode. In other direct conversion detectors operating in the avalanche mode, sensitivities close to the single photon response are also explored for mammography and breast tomosynthesis. The potential advantages and challenges of this approach are described. Dedicated breast CT brings x-ray imaging of the breast to true tomographic 3D imaging. It can eliminate the tissue superposition problem and does not require physical compression of the breast. Using cone beam geometry and a flat-panel detector, several hundred projections are acquired and reconstructed to near isotropic voxels. Multiplanar reconstruction facilitates viewing the breast volume in any desired orientation. Ongoing clinical studies, the current state-of-the art, and research to advance the technology are described. Learning Objectives: To understand the ongoing developments in x-ray imaging of the breast To understand the approaches and applications of spectral mammography To understand the potential advantages of distributed x-ray source arrays for digital breast tomosynthesis To understand the ongoing developments in detector technology for digital mammography and breast tomosynthesis To understand the current state-of-the-art for dedicated cone-beam breast CT and research to advance the technology. Research collaboration with Koning Corporation

TU-EF-207-05: Dedicated Cone-beam Breast CT

Energy Technology Data Exchange (ETDEWEB)

Vedantham, S. [Univ. of Massachusetts Medical School (United States)

2015-06-15

mode due to lower photon fluence per projection. This may require fast-frame acquisition and symmetric or asymmetric pixel binning in some systems. Recent studies investigated the performance of increased conversion layer thickness for contrast-enhanced imaging of the breast in dual-energy acquisition mode. In other direct conversion detectors operating in the avalanche mode, sensitivities close to the single photon response are also explored for mammography and breast tomosynthesis. The potential advantages and challenges of this approach are described. Dedicated breast CT brings x-ray imaging of the breast to true tomographic 3D imaging. It can eliminate the tissue superposition problem and does not require physical compression of the breast. Using cone beam geometry and a flat-panel detector, several hundred projections are acquired and reconstructed to near isotropic voxels. Multiplanar reconstruction facilitates viewing the breast volume in any desired orientation. Ongoing clinical studies, the current state-of-the art, and research to advance the technology are described. Learning Objectives: To understand the ongoing developments in x-ray imaging of the breast To understand the approaches and applications of spectral mammography To understand the potential advantages of distributed x-ray source arrays for digital breast tomosynthesis To understand the ongoing developments in detector technology for digital mammography and breast tomosynthesis To understand the current state-of-the-art for dedicated cone-beam breast CT and research to advance the technology. Research collaboration with Koning Corporation.

Dynamic helical CT mammography of breast cancer

International Nuclear Information System (INIS)

Yamamoto, Akira; Fukushima, Hitoshi; Okamura, Ryuji; Nakamura, Yoshiaki; Morimoto, Taisuke; Urata, Yoji; Mukaihara, Sumio; Hayakawa, Katsumi

2006-01-01

The purpose of this study was to determine whether dynamic helical computed tomography (CT)-mammography could assist in selecting the most appropriate surgical method in women with breast cancer. Preoperative contrast-enhanced helical CT scanning of the breast was performed on 133 female patients with suspicion of breast cancer at the same time as clinical, mammographic, and/or ultrasonographic examinations. The patients were scanned in the prone position with a specially designed CT-compatible device. A helical scan was made with rapid intravenous bolus injection (3 ml/s) of 100 ml of iodine contrast material. Three-dimensional maximum intensity projection (MIP) images were reconstructed, and CT findings were correlated with surgical and histopathological findings. Histopathological analysis revealed 84 malignant lesions and seven benign lesions. The sensitivity, specificity, and accuracy levels of the CT scanning were 94.6%, 58.6%, and 78.9%. Helical scanning alone revealed additional contralateral carcinomas in three of four patients and additional ipsilateral carcinomas in three of five patients. However, the technique gave false-positive readings in 24 patients. The preoperative CT-mammogram altered the surgical method in six patients. Dynamic helical CT-mammography in the prone position may be one of the choices of adjunct imaging in patients with suspected breast cancer scheduled for surgery. (author)

Analysis on imaging features of mammography in computer radiography and investigation on gray scale transform and energy subtraction

International Nuclear Information System (INIS)

Feng Shuli

2003-01-01

In this dissertation, a novel transform method based on human visual response features for gray scale mammographic imaging in computer radiography (CR) is presented. The parameters for imaging quality on CR imaging for mammography were investigated experimentally. In addition, methods for image energy subtraction and a novel method of image registration for mammography of CR imaging are presented. Because the images are viewed and investigated by humans, the method of displaying differences in gray scale images is more convenient if the gray scale differences are displayed in a manner commensurate with human visual response principles. Through transformation of image gray scale with this method, the contrast of the image will be enhanced and the capability for humans to extract the useful information from the image will be increased. Tumors and microcalcifications are displayed in a form for humans to view more simply after transforming the image. The method is theoretically and experimentally investigated. Through measurement of the parameters of a geometrically blurred image, MTF, DQE, and ROC on CR imaging, and also comparison with the imaging quality of screen-film systems, the results indicate that CR imaging qualities in DQE and ROC are better than those of screen-film systems. In geometric blur of the image and MTF, the differences in image quality between CR and the screen-film system are very small. The results suggest that the CR system can replace the screen-film system for mammography imaging. In addition, the results show that the optimal imaging energy for CR mammography is about 24 kV. This condition indicates that the imaging energy of the CR system is lower than that of the screen-film system and, therefore, the x-ray dose to the patient for mammography with the CR system is lower than that with the screen-film system. Based on the difference of penetrability of x ray with different wavelength, and the fact that the part of the x-ray beam will pass

Radiographer involvement in mammography image interpretation: A survey of United Kingdom practice

International Nuclear Information System (INIS)

Culpan, A.M.

2016-01-01

Breast cancer is most often diagnosed using x-ray mammography. Traditionally mammography images have been interpreted and reported by medically qualified practitioners – radiologists. Due to radiologist workforce shortages in recent years some non-medical practitioners, radiographers, now interpret and report mammography images. The aims of this survey were to describe the characteristics and practices of radiographers who interpret and report mammography images in NHS hospitals in the UK, and in particular to establish the extent of their practice beyond low-risk asymptomatic screening cases. This service evaluation demonstrated that UK radiographers are interpreting and reporting images across the full spectrum of clinical indications for mammography including: low-risk population screening, symptomatic, annual surveillance, family history and biopsy/surgical cases. The survey revealed that radiographers are involved in a diverse range of single and double reading practices where responsibility for diagnostic decision making is shared or transferred between radiologists and/or other radiographers. Comparative analysis of sub-group data suggested that there might be differences in the characteristics and practices of radiographers who interpret only low-risk screening mammograms and those who interpret and report a wider range of cases. The findings of this survey provide a platform for further research to investigate how and why the roles and responsibilities of radiographers who interpret and report mammograms vary between organisations, between practitioners and across different examinations. Further research is also needed to explore the implications of variation in practice for patients, practitioners and service providers. - Highlights: • UK radiographers interpret mammograms across the full spectrum of clinical indications. • UK radiographers are involved in a wide range of single/double mammography reading practices. • Characteristics required for

Cultural views, language ability, and mammography use in Chinese American women.

Science.gov (United States)

Liang, Wenchi; Wang, Judy; Chen, Mei-Yuh; Feng, Shibao; Yi, Bin; Mandelblatt, Jeanne S

2009-12-01

Mammography screening rates among Chinese American women have been reported to be low. This study examines whether and how culture views and language ability influence mammography adherence in this mostly immigrant population. Asymptomatic Chinese American women (n = 466) aged 50 and older, recruited from the Washington, D.C. area, completed a telephone interview. Regular mammography was defined as having two mammograms at age-appropriate recommended intervals. Cultural views were assessed by 30 items, and language ability measured women's ability in reading, writing, speaking, and listening to English. After controlling for risk perception, worry, physician recommendation, family encouragement, and access barriers, women holding a more Chinese/Eastern cultural view were significantly less likely to have had regular mammograms than those having a Western cultural view. English ability was positively associated with mammography adherence. The authors' results imply that culturally sensitive and language-appropriate educational interventions are likely to improve mammography adherence in this population.

Digital mammography with high-resolution storage plates (CR) versus full-field digital mammography (CCD) (DR) for microcalcifications and focal lesions - a retrospective clinical histologic analysis (n = 102)

International Nuclear Information System (INIS)

Schulz-Wendtland, R.; Lell, M.; Wenkel, E.; Boehner, C.; Dassel, M.S.; Bautz, W.

2005-01-01

Purpose: to determine the diagnostic accuracy of microcalcifications and focal lesions in a retrospective clinical-histological study using high-resolution digital phosphor storage plates (hard copy) and full-field digital mammography (hard copy). Materials and methods: from May 2003 to September 2003, 102 patients underwent digital storage plate mammography (CR), using a mammography unit (Mammomat 3000 N, Siemens) in combination with a high resolution (9 lp/mm) digital storage phosphor plate system (pixel size 50 μm) (Fuji/Siemens). After diagnosis and preoperative wire localization, full-field digital mammography (CCD) (DR) was performed with the same exposure parameters. The full-field digital mammography used a CCD-detector (SenoScan) (fisher imaging) with a resolution of 10 Ip/mm and a pixel size of 50 μm. Five investigators determined the diagnosis (BI-RADS trademark I-V) retrospectively after the operation from randomly distributed mediolateral views (hard copy reading). These results were correlated with the final histology. Results: the diagnostic accuracy of digital storage plate mammography (CR) and full-field digital mammography (CCD) (DR) was 73% and 71% for all findings (n = 102), 73% and 71% for microcalcifications (n = 51), and 72% and 70% for focal lesions (n = 51). The overall results showed no difference. Conclusion: our findings indicate the equivalence of high-resolution digital phosphor storage plate mammography (CR) and full-field digital mammography (CCD) (DR). (orig.)

Scintillator performance considerations for dedicated breast computed tomography

Science.gov (United States)

Vedantham, Srinivasan; Shi, Linxi; Karellas, Andrew

2017-09-01

Dedicated breast computed tomography (BCT) is an emerging clinical modality that can eliminate tissue superposition and has the potential for improved sensitivity and specificity for breast cancer detection and diagnosis. It is performed without physical compression of the breast. Most of the dedicated BCT systems use large-area detectors operating in cone-beam geometry and are referred to as cone-beam breast CT (CBBCT) systems. The large-area detectors in CBBCT systems are energy-integrating, indirect-type detectors employing a scintillator that converts x-ray photons to light, followed by detection of optical photons. A key consideration that determines the image quality achieved by such CBBCT systems is the choice of scintillator and its performance characteristics. In this work, a framework for analyzing the impact of the scintillator on CBBCT performance and its use for task-specific optimization of CBBCT imaging performance is described.

COMPUTING THE VOCABULARY DEMANDS OF L2 READING

Directory of Open Access Journals (Sweden)

Tom Cobb

2007-02-01

Full Text Available Linguistic computing can make two important contributions to second language (L2 reading instruction. One is to resolve longstanding research issues that are based on an insufficiency of data for the researcher, and the other is to resolve related pedagogical problems based on insufficiency of input for the learner. The research section of the paper addresses the question of whether reading alone can give learners enough vocabulary to read. When the computer’s ability to process large amounts of both learner and linguistic data is applied to this question, it becomes clear that, for the vast majority of L2 learners, free or wide reading alone is not a sufficient source of vocabulary knowledge for reading. But computer processing also points to solutions to this problem. Through its ability to reorganize and link documents, the networked computer can increase the supply of vocabulary input that is available to the learner. The development section of the paper elaborates a principled role for computing in L2 reading pedagogy, with examples, in two broad areas, computer-based text design and computational enrichment of undesigned texts.

Abnormality Detection in Mammography using Deep Convolutional Neural Networks

OpenAIRE

Xi, Pengcheng; Shu, Chang; Goubran, Rafik

2018-01-01

Breast cancer is the most common cancer in women worldwide. The most common screening technology is mammography. To reduce the cost and workload of radiologists, we propose a computer aided detection approach for classifying and localizing calcifications and masses in mammogram images. To improve on conventional approaches, we apply deep convolutional neural networks (CNN) for automatic feature learning and classifier building. In computer-aided mammography, deep CNN classifiers cannot be tra...

Visibility of microcalcifications in computed and screen-film mammography

International Nuclear Information System (INIS)

Cowen, Arnold R.; Launders, Jason H.; Jadav, Mark; Brettle, David S.

1997-01-01

Due to the clinically and technically demanding nature of breast x-ray imaging, mammography still remains one of the few essentially film-based radiological imaging techniques in modern medical imaging. There are a range of possible benefits available if a practical and economical direct digital imaging technique can be introduced to routine clinical practice. There has been much debate regarding the minimum specification required for direct digital acquisition. One such direct digital system available is computed radiography (CR), which has a modest specification when compared with modern screen-film mammography (SFM) systems. This paper details two psychophysical studies in which the detection of simulated microcalcifications with CR has been directly compared to that with SFM. The first study found that under scatter-free conditions the minimum detectable size of micro calcification was approximately 130 μm for both SFM and CR. The second study found that SFM had a 4.6% higher probability of observers being able to correctly identify the shape of 350 μm diameter test details; there was no significant difference for either larger or smaller test details. From the results of these studies it has been demonstrated that the modest specification of CR, in terms of limiting resolution, does not translate into a dramatic difference in the perception of details at the limit of detectability. When judging the imaging performance of a system it is more important to compare the signal-to-noise ratio transfer spectrum characteristics, rather than simply the modulation transfer function. (author)

Our trial to improve patient positioning during mammography

International Nuclear Information System (INIS)

Nakayama, Takashi; Kotsuma, Yoshikazu; Hiramatsu, Sawako

2007-01-01

For effective breast cancer screening, reading of high-quality mammograms is essential, and for this purpose proper patient positioning during mammography is important. At our Shin-Osaka Mammography Seminar, which includes eight institutions, a physician and nine radiology technicians get together weekly in order to critically review mammogram reading and techniques for obtaining good mammograms. We have recognized that patient positioning has a great effect on mammogram quality, particularly for women in their 40 s who have dense mammary glands, and we have adopted a digital mammography system, or comparative mammography for such patients. Since July 2005, we have critically reviewed positioning every 3 or 4 months with the aim of improving our technique. Eight institutions have participated in this trial, each contributing mammograms taken recently from 20 to 30 consecutive participants, and the grade of positioning has been determined according to the Institutional Mammogram Estimation Standard (6 items, each scoring a maximum of 4 points, total 24 points) proposed by the Central Committee for Quality Control of Mammography Screening. The estimation has been done by both ourselves and committee members. When a total of 20 points or more is obtained and all 6 items score 3 points or more, it is considered that the positioning has been good, and this is termed ''Positioning A'' (P-A). On the other hand, if the total score is less than 20 points, and any one of the 6 items scores less than 3 points, it is considered that positioning has been inadequate, and this is termed ''Positioning-D'' (P-D). At the first review meeting, which was held before our critical study, P-A accounted for 48% of cases, and this had improved to 72% at the second meeting, and to 66% at the third. P-D accounted for 41% of cases at the first meeting, 20% at the second, and 21% at the third. Thus our trial involving discussion between a physician and technicians to critically review good

Position paper on screening for breast cancer by the European Society of Breast Imaging (EUSOBI) and 30 national breast radiology bodies from Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Israel, Lithuania, Moldova, The Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Spain, Sweden, Switzerland and Turkey.

Science.gov (United States)

Sardanelli, Francesco; Aase, Hildegunn S; Álvarez, Marina; Azavedo, Edward; Baarslag, Henk J; Balleyguier, Corinne; Baltzer, Pascal A; Beslagic, Vanesa; Bick, Ulrich; Bogdanovic-Stojanovic, Dragana; Briediene, Ruta; Brkljacic, Boris; Camps Herrero, Julia; Colin, Catherine; Cornford, Eleanor; Danes, Jan; de Geer, Gérard; Esen, Gul; Evans, Andrew; Fuchsjaeger, Michael H; Gilbert, Fiona J; Graf, Oswald; Hargaden, Gormlaith; Helbich, Thomas H; Heywang-Köbrunner, Sylvia H; Ivanov, Valentin; Jónsson, Ásbjörn; Kuhl, Christiane K; Lisencu, Eugenia C; Luczynska, Elzbieta; Mann, Ritse M; Marques, Jose C; Martincich, Laura; Mortier, Margarete; Müller-Schimpfle, Markus; Ormandi, Katalin; Panizza, Pietro; Pediconi, Federica; Pijnappel, Ruud M; Pinker, Katja; Rissanen, Tarja; Rotaru, Natalia; Saguatti, Gianni; Sella, Tamar; Slobodníková, Jana; Talk, Maret; Taourel, Patrice; Trimboli, Rubina M; Vejborg, Ilse; Vourtsis, Athina; Forrai, Gabor

2017-07-01

EUSOBI and 30 national breast radiology bodies support mammography for population-based screening, demonstrated to reduce breast cancer (BC) mortality and treatment impact. According to the International Agency for Research on Cancer, the reduction in mortality is 40 % for women aged 50-69 years taking up the invitation while the probability of false-positive needle biopsy is screening. Mortality reduction was also observed for the age groups 40-49 years and 70-74 years, although with "limited evidence". Thus, we firstly recommend biennial screening mammography for average-risk women aged 50-69 years; extension up to 73 or 75 years, biennially, is a second priority, from 40-45 to 49 years, annually, a third priority. Screening with thermography or other optical tools as alternatives to mammography is discouraged. Preference should be given to population screening programmes on a territorial basis, with double reading. Adoption of digital mammography (not film-screen or phosphor-plate computer radiography) is a priority, which also improves sensitivity in dense breasts. Radiologists qualified as screening readers should be involved in programmes. Digital breast tomosynthesis is also set to become "routine mammography" in the screening setting in the next future. Dedicated pathways for high-risk women offering breast MRI according to national or international guidelines and recommendations are encouraged. • EUSOBI and 30 national breast radiology bodies support screening mammography. • A first priority is double-reading biennial mammography for women aged 50-69 years. • Extension to 73-75 and from 40-45 to 49 years is also encouraged. • Digital mammography (not film-screen or computer radiography) should be used. • DBT is set to become "routine mammography" in the screening setting in the next future.

Influence of age and menstrual cycle on mammography and MR imaging of the breast

International Nuclear Information System (INIS)

Mueller-Schimpfle, M.; Ohmenhaeuser, K.; Claussen, C.D.

1997-01-01

Age and menstrual cycle have an important influence on the breast. This well-known fact is experienced in the daily routine of gynecologists and radiologists. The number of publications addressing the effect of these influences on imaging, however, is surprisingly low. The aim of this work is to describe the influences of age and menstrual cycle on the breast and to address their clinical relevance for mammography and MR mammography. Therefore, own data are presented concerning the age and menstrual cycle influences on breast parenchyma in dynamic MR mammography. Literature data are used to correlate mammography and MR imaging findings with these influences. The changes of the breast due to age and menstrual cycle have important direct implications on performing and reading conventional mammography and MR mammography. The knowledge of these changes is also helpful in the interpretation of findings when comparing different methods. Finally, the data gained by using imaging methods enable important basic insights into physiology and physiopathology of the breast in vivo. (orig.) [de

Screening mammography-detected cancers: the sensitivity of the computer-aided detection system as applied to full-field digital mammography

International Nuclear Information System (INIS)

Yang, Sang Kyu; Cho, Nariya; Ko, Eun Sook; Kim, Do Yeon; Moon, Woo Kyung

2006-01-01

We wanted to evaluate the sensitivity of the computer-aided detection (CAD) system for performing full-field digital mammography (FFDM) on the breast cancers that were originally detected by screening mammography. The CAD system (Image Checker v3.1, R2 Technology, Los Altos, Calif.) together with a full-field digital mammography system (Senographe 2000D, GE Medical Systems, Buc, France) was prospectively applied to the mammograms of 70 mammographically detected breast cancer patients (age range, 37-69; median age, 51 years) who had negative findings on their clinical examinations. The sensitivity of the CAD system, according to histopathologic findings and radiologic primary features (i.e, mass, microcalcifications or mass with microcalcifications) and also the false-positive marking rate were then determined. The CAD system correctly depicted 67 of 70 breast cancer lesions (97.5%). The CAD system marked 29 of 30 breast cancers that presented with microcalcifications only (sensitivity 96.7%) and all 18 breast cancers the presented with mass together with microcalcifications (sensitivity 100%). Twenty of the 22 lesions that appeared as a mass only were marked correctly by the CAD system (sensitivity 90.9%). The CAD system correctly depicted all 22 lesions of ductal carcinoma in situ (sensitivity: 100%), all 13 lesions of invasive ductal carcinoma with ductal carcinoma in situ (sensitivity: 100%) and the 1 lesion of invasive lobular carcinoma (sensitivity: 100%). Thirty one of the 34 lesions of invasive ductal carcinoma were marked correctly by the CAD system (sensitivity: 91.8%). The rate of false-positive marks was 0.21 mass marks per image and 0.16 microcalcification marks per image. The overall rate of false-positive marks was 0.37 per image. The CAD system using FFDM is useful for the detection of asymptomatic breast cancers, and it has a high overall tumor detection rate. The false negative cases were found in relatively small invasive ductal carcinoma

Screening mammography-detected cancers: the sensitivity of the computer-aided detection system as applied to full-field digital mammography

Energy Technology Data Exchange (ETDEWEB)

Yang, Sang Kyu; Cho, Nariya; Ko, Eun Sook; Kim, Do Yeon; Moon, Woo Kyung [College of Medicine Seoul National University and The Insititute of Radiation Medicine, Seoul National University Research Center, Seoul (Korea, Republic of)

2006-04-15

We wanted to evaluate the sensitivity of the computer-aided detection (CAD) system for performing full-field digital mammography (FFDM) on the breast cancers that were originally detected by screening mammography. The CAD system (Image Checker v3.1, R2 Technology, Los Altos, Calif.) together with a full-field digital mammography system (Senographe 2000D, GE Medical Systems, Buc, France) was prospectively applied to the mammograms of 70 mammographically detected breast cancer patients (age range, 37-69; median age, 51 years) who had negative findings on their clinical examinations. The sensitivity of the CAD system, according to histopathologic findings and radiologic primary features (i.e, mass, microcalcifications or mass with microcalcifications) and also the false-positive marking rate were then determined. The CAD system correctly depicted 67 of 70 breast cancer lesions (97.5%). The CAD system marked 29 of 30 breast cancers that presented with microcalcifications only (sensitivity 96.7%) and all 18 breast cancers the presented with mass together with microcalcifications (sensitivity 100%). Twenty of the 22 lesions that appeared as a mass only were marked correctly by the CAD system (sensitivity 90.9%). The CAD system correctly depicted all 22 lesions of ductal carcinoma in situ (sensitivity: 100%), all 13 lesions of invasive ductal carcinoma with ductal carcinoma in situ (sensitivity: 100%) and the 1 lesion of invasive lobular carcinoma (sensitivity: 100%). Thirty one of the 34 lesions of invasive ductal carcinoma were marked correctly by the CAD system (sensitivity: 91.8%). The rate of false-positive marks was 0.21 mass marks per image and 0.16 microcalcification marks per image. The overall rate of false-positive marks was 0.37 per image. The CAD system using FFDM is useful for the detection of asymptomatic breast cancers, and it has a high overall tumor detection rate. The false negative cases were found in relatively small invasive ductal carcinoma.

Promoting mammography screening among Chinese American women using a message-framing intervention.

Science.gov (United States)

Sun, Yiyuan; Sarma, Elizabeth A; Moyer, Anne; Messina, Catherine R

2015-07-01

This study examined the role of women's perceptions about the relative pros versus cons (decisional balance) of mammography in moderating Chinese American women's responses to gain- and loss-framed messages that promote mammography. One hundred and forty-three Chinese American women who were currently nonadherent to guidelines for receiving annual screening mammograms were randomly assigned to read either a gain- or loss-framed culturally appropriate print brochure about mammography screening. Mammography screening was self-reported at a 2-month follow-up. Although there was not a main effect for message frame, the hypothesized interaction between message frame and decisional balance was significant, indicating that women who received a framed message that matched their decisional balance were significantly more likely to have obtained a mammogram by the follow-up than women who received a mismatched message. Results suggest that decisional balance, and more generally, perceptions about mammography, may be an important moderator of framing effects for mammography among Chinese American women. The match between message frame and decisional balance should be considered when attempting to encourage Chinese American women to receive mammography screening, as a match between the two may be most persuasive. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Exploratory survey of image quality on CR digital mammography imaging systems in Mexico

International Nuclear Information System (INIS)

Gaona, E.; Rivera, T.; Arreola, M.; Franco, J.; Molina, N.; Alvarez, B.; Azorín, C.G.; Casian, G.

2014-01-01

The purpose of this study was to assess the current status of image quality and dose in computed radiographic digital mammography (CRDM) systems. Studies included CRDM systems of various models and manufacturers which dose and image quality comparisons were performed. Due to the recent rise in the use of digital radiographic systems in Mexico, CRDM systems are rapidly replacing conventional film-screen systems without any regard to quality control or image quality standards. Study was conducted in 65 mammography facilities which use CRDM systems in the Mexico City and surrounding States. The systems were tested as used clinically. This means that the dose and beam qualities were selected using the automatic beam selection and photo-timed features. All systems surveyed generate laser film hardcopies for the radiologist to read on a scope or mammographic high luminance light box. It was found that 51 of CRDM systems presented a variety of image artefacts and non-uniformities arising from inadequate acquisition and processing, as well as from the laser printer itself. Undisciplined alteration of image processing settings by the technologist was found to be a serious prevalent problem in 42 facilities. Only four of them showed an image QC program which is periodically monitored by a medical physicist. The Average Glandular Dose (AGD) in the surveyed systems was estimated to have a mean value of 2.4 mGy. To improve image quality in mammography and make more efficient screening mammographic in early detection of breast cancer is required new legislation. - Highlights: • Radiation dose in CR digital mammography (CRDM) systems was determined. • Image quality related with dose in CR digital mammography (CRDM) systems was analysed. • Image processing artefacts were observed and correlated with dose. • Measured entrance dose by TL phosphors could be good parameter for radiation protection optimization in patient

Technical quality control - constancy controls for digital mammography systems

International Nuclear Information System (INIS)

Pedersen, K.; Landmark, I.D.; Bredholt, K.; Hauge, I.H.R.

2009-04-01

To ensure the quality of mammographic images, so-called constancy control tests are performed frequently. The report contains a programme for constancy control of digital mammography systems, encompassing the mammography unit, computed radiography (CR) systems, viewing conditions and displays, printers, and procedures for data collection for patient dose calculations. (Author)

Construction of a catalog of X-ray spectra for mammography simulations

International Nuclear Information System (INIS)

Santos, L.C.S.; Vieira, J.W.

2017-01-01

Computational Exposure Models (MCEs) allow the simulation of the interaction of radiation with matter by means of Monte Carlo (MC) techniques. Generally, MCEs are composed of phantom, simulator algorithms of radioactive sources and an MC code to simulate the transport, interaction of the radiation with matter and to evaluate the energy deposited in regions of interest. To compose an MCE for simulations in mammography, the construction of a catalog of X-ray spectra was started, based on the catalog model constructed and using until then in MCEs by the Group of Research in Numerical Dosimetry and by the Group of Research in Computational Dosimetry & Embedded Systems (both referenced in this work as GDN). Potential of 25 kV and 35 kV and used target / filter were applied to the tube: Mo / Mo. The file containing the spectra was read correctly by EGSnrc

Evaluation of an image receptor for computed radiography system in mammography

International Nuclear Information System (INIS)

Dantas, Marcelino V.A.; Rosado, Paulo H.G.; Santana, Priscila C.; Alvarenga, Frederico L.; Nogueira, Maria S.

2009-01-01

In this work, the performance of an image receptor for computed radiography system, Kodak CR850, was assessed through tests, recommended by the European protocol, with a specific image plate for mammography where were analyzed the Contrast-to-noise ratio (CNR) and uniformity and linearity of detector. The CNRs were 14.1, 11.7, 10.3, 8.4, 7.1 and 5.9 for 2, 3, 4, 5, 6 and 7 cm polymethylmethacrylate (PMMA) thickness, respectively. The linearity between detector response and dose, obtained a correlation coefficient (R 2 ) greater than 0.99, and the maximum variation found in the detector uniformity calculation was 3.94 in the lower right corner. (author)

Digital mammography: Signal-extraction strategies for computer-aided detection of microcalcifications

International Nuclear Information System (INIS)

Chan, H.P.; Doi, K.; Metz, C.E.; Vyborny, C.J.; Lam, K.L.; Schmidt, R.A.

1987-01-01

The authors found that the structured background of a mammogram can be removed effectively by either a difference-image technique (using a matched filter in combination with a median filter, a contrast-reversal filter, or a box-rim filter) or a visual response filter alone. Locally adaptive gray-level thresholding and region-growing techniques can then be employed to extract microcalcifications from the processed image. Signals are further distinguished from noise or artifacts by their size, contrast, and clustering properties. The authors studied the dependence of the detectability of microcalcifications on the various signal-extraction strategies. Potential application of the computer-aided system to mammography is assessed by its performance on clinical mammograms

Computer-aided detection (CAD) in mammography: Does it help the junior or the senior radiologist?

International Nuclear Information System (INIS)

Balleyguier, Corinne; Kinkel, Karen; Fermanian, Jacques; Malan, Sebastien; Djen, Germaine; Taourel, Patrice; Helenon, Olivier

2005-01-01

Objectives: To evaluate the impact of a computer-aided detection (CAD) system on the ability of a junior and senior radiologist to detect breast cancers on mammograms, and to determine the potential of CAD as a teaching tool in mammography. Methods: Hundred biopsy-proven cancers and 100 normal mammograms were randomly analyzed by a CAD system. The sensitivity (Se) and specificity (Sp) of the CAD system were calculated. In the second phase, to simulate daily practice, 110 mammograms (97 normal or with benign lesions, and 13 cancers) were examined independently by a junior and a senior radiologist, with and without CAD. Interpretations were standardized according to BI-RADS classification. Sensitivity, Specificity, positive and negative predictive values (PPV, NPV) were calculated for each session. Results: For the senior radiologist, Se slightly improved from 76.9 to 84.6% after CAD analysis (NS) (one case of clustered microcalcifications case overlooked by the senior radiologist was detected by CAD). Sp, PPV and PNV did not change significantly. For the junior radiologist, Se improved from 61.9 to 84.6% (significant change). Three cancers overlooked by the junior radiologist were detected by CAD. Sp was unchanged. Conclusion: CAD mammography proved more useful for the junior than for the senior radiologist, improving sensitivity. The CAD system may represent a useful educational tool for mammography

Computation of beam quality parameters for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations in mammography

International Nuclear Information System (INIS)

Kharrati, Hedi; Zarrad, Boubaker

2003-01-01

A computer program was implemented to predict mammography x-ray beam parameters in the range 20-40 kV for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations. The computation method used to simulate mammography x-ray spectra is based on the Boone et al. model. The beam quality parameters such as the half-value layer (HVL), the homogeneity coefficient (HC), and the average photon energy were computed by simulating the interaction of the spectrum photons with matter. The checking of this computation was done using a comparison of the results with published data and measured values obtained at the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency. The predicted values with a mean deviation of 3.3% of HVL, 3.7% of HC, and 1.5% of average photon energy show acceptable agreement with published data and measurements for all target/filter combinations in the 23-40 kV range. The accuracy of this computation can be considered clinically acceptable and can allow an appreciable estimation for the beam quality parameters

TU-EF-207-02: Spectral Mammography Based on Photon Counting Detectors

Energy Technology Data Exchange (ETDEWEB)

Molloi, S. [University of California (United States)

2015-06-15

mode due to lower photon fluence per projection. This may require fast-frame acquisition and symmetric or asymmetric pixel binning in some systems. Recent studies investigated the performance of increased conversion layer thickness for contrast-enhanced imaging of the breast in dual-energy acquisition mode. In other direct conversion detectors operating in the avalanche mode, sensitivities close to the single photon response are also explored for mammography and breast tomosynthesis. The potential advantages and challenges of this approach are described. Dedicated breast CT brings x-ray imaging of the breast to true tomographic 3D imaging. It can eliminate the tissue superposition problem and does not require physical compression of the breast. Using cone beam geometry and a flat-panel detector, several hundred projections are acquired and reconstructed to near isotropic voxels. Multiplanar reconstruction facilitates viewing the breast volume in any desired orientation. Ongoing clinical studies, the current state-of-the art, and research to advance the technology are described. Learning Objectives: To understand the ongoing developments in x-ray imaging of the breast To understand the approaches and applications of spectral mammography To understand the potential advantages of distributed x-ray source arrays for digital breast tomosynthesis To understand the ongoing developments in detector technology for digital mammography and breast tomosynthesis To understand the current state-of-the-art for dedicated cone-beam breast CT and research to advance the technology. Research collaboration with Koning Corporation.

TU-EF-207-02: Spectral Mammography Based on Photon Counting Detectors

International Nuclear Information System (INIS)

Molloi, S.

2015-01-01

mode due to lower photon fluence per projection. This may require fast-frame acquisition and symmetric or asymmetric pixel binning in some systems. Recent studies investigated the performance of increased conversion layer thickness for contrast-enhanced imaging of the breast in dual-energy acquisition mode. In other direct conversion detectors operating in the avalanche mode, sensitivities close to the single photon response are also explored for mammography and breast tomosynthesis. The potential advantages and challenges of this approach are described. Dedicated breast CT brings x-ray imaging of the breast to true tomographic 3D imaging. It can eliminate the tissue superposition problem and does not require physical compression of the breast. Using cone beam geometry and a flat-panel detector, several hundred projections are acquired and reconstructed to near isotropic voxels. Multiplanar reconstruction facilitates viewing the breast volume in any desired orientation. Ongoing clinical studies, the current state-of-the art, and research to advance the technology are described. Learning Objectives: To understand the ongoing developments in x-ray imaging of the breast To understand the approaches and applications of spectral mammography To understand the potential advantages of distributed x-ray source arrays for digital breast tomosynthesis To understand the ongoing developments in detector technology for digital mammography and breast tomosynthesis To understand the current state-of-the-art for dedicated cone-beam breast CT and research to advance the technology. Research collaboration with Koning Corporation

European radiographers' challenges from mammography education and clinical practice - an integrative review.

Science.gov (United States)

Metsälä, Eija; Richli Meystre, Nicole; Pires Jorge, José; Henner, Anja; Kukkes, Tiina; Sá Dos Reis, Cláudia

2017-06-01

This study aims to identify European radiographers' challenges in clinical performance in mammography and the main areas of mammography that require more and better training. An extensive search was performed to identify relevant studies focused on clinical practice, education and training in mammography published between January 2010 and December 2015 in the English language. The data were analysed by using deductive thematic analysis. A total of 27 full text articles were read, evaluating their quality. Sixteen articles out of 27 were finally selected for this integrative review. The main challenges of radiographers' mammography education/training can be divided into three groups: training needs, challenges related to radiographers, and challenges related to the organization of education. The most common challenges of clinical performance in mammography among European radiographers involved technical performance, the quality of practices, and patient-centeredness. The introduction of harmonized mammography guidelines across Europe may serve as an evidence-based tool to be implemented in practice and education. However, the variability in human and material resources as well as the different cultural contexts should be considered during this process. • Radiographers' awareness of their professional identity and enhancing multiprofessional cooperation in mammography. • Radiographers' responsibilities regarding image quality (IQ) and optimal breast imaging performance. • Patient-centred mammography services focusing on the psychosocial needs of the patient. • Challenges: positioning, QC-testing, IQ-assessment, optimization of breast compression, communication, teamwork, and patient-centred care. • Introduction of evidence-based guidelines in Europe to harmonize mammography practice and education.

Dual-energy contrast-enhanced spectral mammography (CESM).

Science.gov (United States)

Daniaux, Martin; De Zordo, Tobias; Santner, Wolfram; Amort, Birgit; Koppelstätter, Florian; Jaschke, Werner; Dromain, Clarisse; Oberaigner, Willi; Hubalek, Michael; Marth, Christian

2015-10-01

Dual-energy contrast-enhanced mammography is one of the latest developments in breast care. Imaging with contrast agents in breast cancer was already known from previous magnetic resonance imaging and computed tomography studies. However, high costs, limited availability-or high radiation dose-led to the development of contrast-enhanced spectral mammography (CESM). We reviewed the current literature, present our experience, discuss the advantages and drawbacks of CESM and look at the future of this innovative technique.

Introduction of organised mammography screening in tyrol: results of a one-year pilot phase

Directory of Open Access Journals (Sweden)

Daniaux Martin

2011-02-01

Full Text Available Abstract Background Efficiency and efficacy of organised mammography screening programs have been proven in large randomised trials. But every local implementation of mammography screening has to check whether the well established quality standards are met. Therefore it was the aim of this study to analyse the most common quality indices after introducing organised mammography screening in Tyrol, Austria, in a smooth transition from the existing system of opportunistic screening. Methods In June 2007, the system of opportunistic mammography screening in Tyrol was changed to an organised system by introducing a personal invitation system, a training program, a quality assurance program and by setting up a screening database. All procedures are noted in a written protocol. Most EU recommendations for organised mammography screening were followed, except double reading. All women living in Tyrol and covered by social insurance are now invited for a mammography, in age group 40-59 annually and in age group 60-69 biannually. Screening mammography is offered mainly by radiologists in private practice. We report on the results of the first year of piloting organised mammography screening in two counties in Tyrol. Results 56,432 women were invited. Estimated participation rate was 34.5% at one year of follow-up (and 55.5% at the second year of follow-up; 3.4% of screened women were recalled for further assessment or intermediate screening within six months. Per 1000 mammograms nine biopsies were performed and four breast cancer cases detected (N = 68. Of invasive breast cancer cases 34.4% were ≤ 10 mm in size and 65.6% were node-negative. In total, six interval cancer cases were detected during one year of follow-up; this is 19% of the background incidence rate. Conclusions In the Tyrolean breast cancer screening program, a smooth transition from a spontaneous to an organised mammography screening system was achieved in a short time and with minimal

Interval breast cancers in the 'screening with tomosynthesis or standard mammography' (STORM) population-based trial.

Science.gov (United States)

Houssami, Nehmat; Bernardi, Daniela; Caumo, Francesca; Brunelli, Silvia; Fantò, Carmine; Valentini, Marvi; Romanucci, Giovanna; Gentilini, Maria A; Zorzi, Manuel; Macaskill, Petra

2018-04-01

The prospective 'screening with tomosynthesis or standard mammography' (STORM) trial recruited women participating in biennial breast screening in Italy (2011-2012), and compared sequential screen-readings based on 2D-mammography alone or based on tomosynthesis (integrated 2D/3D-mammography). The STORM trial showed that tomosynthesis screen-reading significantly increased breast cancer detection compared to 2D-mammography alone. The present study completes reporting of the trial by examining interval breast cancers ascertained at two year follow-up. 9 interval breast cancers were identified; the estimated interval cancer rate was 1.23/1000 screens [9/7292] (95%CI 0.56 to 2.34) or 1.24/1000 negative screens [9/7235] (95%CI 0.57 to 2.36). In concurrently screened women who attended the same screening services and received 2D-mammography, interval cancer rate was 1.60/1000 screens [40/25,058] (95% CI 1.14 to 2.17) or 1.61/1000 negative screens [40/24,922] (95% CI 1.15 to 2.18). Estimated screening sensitivity for the STORM trial was 85.5% [59/69] (95%CI 75.0%-92.8%), and that for 2D-mammography screening was 77.3% [136/176] (95%CI 70.4%-83.2%). Interval breast cancer rate amongst screening participants in the STORM trial was marginally lower (and screening sensitivity higher) than estimates amongst 2D-screened women; these findings should be interpreted with caution given the small number of interval cases and the sample size of the trial. Much larger screening studies, or pooled analyses, are required to examine interval cancer rates arising after breast tomosynthesis screening versus digital mammography screening. Copyright © 2018 Elsevier Ltd. All rights reserved.

Could running experience on SPMD computers contribute to the architectural choices for future dedicated computers for high energy physics simulation

International Nuclear Information System (INIS)

Jejcic, A.; Maillard, J.; Silva, J.; Auguin, M.; Boeri, F.

1989-01-01

Results obtained on strongly coupled parallel computer are reported. They concern Monte-Carlo simulation and pattern recognition. Though the calculations were made on an experimental computer of rather low processing power, it is believed that the quoted figures could give useful indications on architectural choices for dedicated computers

Addition of tomosynthesis to conventional digital mammography: effect on image interpretation time of screening examinations.

Science.gov (United States)

Dang, Pragya A; Freer, Phoebe E; Humphrey, Kathryn L; Halpern, Elkan F; Rafferty, Elizabeth A

2014-01-01

To determine the effect of implementing a screening tomosynthesis program on real-world clinical performance by quantifying differences between interpretation times for conventional screening mammography and combined tomosynthesis and mammography for multiple participating radiologists with a wide range of experience in a large academic center. In this HIPAA-compliant, institutional review board-approved study, 10 radiologists prospectively read images from screening digital mammography or screening combined tomosynthesis and mammography examinations for 1-hour-long uninterrupted sessions. Images from 3665 examinations (1502 combined and 2163 digital mammography) from July 2012 to January 2013 were interpreted in at least five sessions per radiologist per modality. The number of cases reported during each session was recorded for each reader. The experience level for each radiologist was also correlated to the average number of cases reported per hour. Analysis of variance was used to assess the number of studies interpreted per hour. A linear regression model was used to evaluate correlation between breast imaging experience and time taken to interpret images from both modalities. The mean number of studies interpreted in hour was 23.8 ± 0.55 (standard deviation) (range, 14.4-40.4) for combined tomosynthesis and mammography and 34.0 ± 0.55 (range, 20.4-54.3) for digital mammography alone. A mean of 10.2 fewer studies were interpreted per hour during combined tomosynthesis and mammography compared with digital mammography sessions (P tomosynthesis and mammography and 1.9 minutes ± 0.6 (range, 1.1-3.0) for digital mammography; interpretation time with combined tomosynthesis and mammography was 0.9 minute longer (47% longer) compared with digital mammography alone (P tomosynthesis and mammography examinations decreased (R(2) = 0.52, P = .03). Addition of tomosynthesis to mammography results in increased time to interpret images from screening examinations compared

Could running experience on SPMD computers contribute to the architectural choices for future dedicated computers for high energy physics simulation?

International Nuclear Information System (INIS)

Jejcic, A.; Maillard, J.; Silva, J.; Auguin, M.; Boeri, F.

1989-01-01

Results obtained on a strongly coupled parallel computer are reported. They concern Monte-Carlo simulation and pattern recognition. Though the calculations were made on an experimental computer of rather low processing power, it is believed that the quoted figures could give useful indications on architectural choices for dedicated computers. (orig.)

Computer-aided detection of breast masses: Four-view strategy for screening mammography

International Nuclear Information System (INIS)

Wei Jun; Chan Heangping; Zhou Chuan; Wu Yita; Sahiner, Berkman; Hadjiiski, Lubomir M.; Roubidoux, Marilyn A.; Helvie, Mark A.

2011-01-01

Purpose: To improve the performance of a computer-aided detection (CAD) system for mass detection by using four-view information in screening mammography. Methods: The authors developed a four-view CAD system that emulates radiologists' reading by using the craniocaudal and mediolateral oblique views of the ipsilateral breast to reduce false positives (FPs) and the corresponding views of the contralateral breast to detect asymmetry. The CAD system consists of four major components: (1) Initial detection of breast masses on individual views, (2) information fusion of the ipsilateral views of the breast (referred to as two-view analysis), (3) information fusion of the corresponding views of the contralateral breast (referred to as bilateral analysis), and (4) fusion of the four-view information with a decision tree. The authors collected two data sets for training and testing of the CAD system: A mass set containing 389 patients with 389 biopsy-proven masses and a normal set containing 200 normal subjects. All cases had four-view mammograms. The true locations of the masses on the mammograms were identified by an experienced MQSA radiologist. The authors randomly divided the mass set into two independent sets for cross validation training and testing. The overall test performance was assessed by averaging the free response receiver operating characteristic (FROC) curves of the two test subsets. The FP rates during the FROC analysis were estimated by using the normal set only. The jackknife free-response ROC (JAFROC) method was used to estimate the statistical significance of the difference between the test FROC curves obtained with the single-view and the four-view CAD systems. Results: Using the single-view CAD system, the breast-based test sensitivities were 58% and 77% at the FP rates of 0.5 and 1.0 per image, respectively. With the four-view CAD system, the breast-based test sensitivities were improved to 76% and 87% at the corresponding FP rates, respectively

Evaluation of the minimum iodine concentration for contrast-enhanced subtraction mammography

International Nuclear Information System (INIS)

Baldelli, P; Bravin, A; Maggio, C Di; Gennaro, G; Sarnelli, A; Taibi, A; Gambaccini, M

2006-01-01

Early manifestation of breast cancer is often very subtle and is displayed in a complex and variable pattern of normal anatomy that may obscure the disease. The use of dual-energy techniques, that can remove the structural noise, and contrast media, that enhance the region surrounding the tumour, could help us to improve the detectability of the lesions. The aim of this work is to investigate the use of an iodine-based contrast medium in mammography with two different double exposure techniques: K-edge subtraction mammography and temporal subtraction mammography. Both techniques have been investigated by using an ideal source, like monochromatic beams produced at a synchrotron radiation facility and a clinical digital mammography system. A dedicated three-component phantom containing cavities filled with different iodine concentrations has been developed and used for measurements. For each technique, information about the minimum iodine concentration, which provides a significant enhancement of the detectability of the pathology by minimizing the risk due to high dose and high concentration of contrast medium, has been obtained. In particular, for cavities of 5 and 8 mm in diameter filled with iodine solutions, the minimum concentration needed to obtain a contrast-to-noise ratio of 5 with a mean glandular dose of 2 mGy has been calculated. The minimum concentrations estimated with monochromatic beams and K-edge subtraction mammography are 0.9 mg ml -1 and 1.34 mg ml -1 for the biggest and smallest details, respectively, while for temporal subtraction mammography they are 0.84 mg ml -1 and 1.31 mg ml -1 . With the conventional clinical system the minimum concentrations for the K-edge subtraction mammography are 4.13 mg ml -1 (8 mm diameter) and 5.75 mg ml -1 (5 mm diameter), while for the temporal subtraction mammography they are 1.01 mg ml -1 (8 mm diameter) and 1.57 mg ml -1 (5 mm diameter)

Studies on the calibration of mammography automatic exposure mode with computed radiology

International Nuclear Information System (INIS)

Zhu Hongzhou; Shao Guoliang; Shi Lei; Liu Qing

2010-01-01

Objective: To realize the optimization of image quality and radiation dose by correcting mammography automatic exposure, according to automatic exposure controlled mode of mammography film-screen system. Methods: The film-screen system (28 kV) was applied to perform automatic exposure of plexiglass (40 mm) and get the standard dose of exposure, the exposure mode of CR base on LgM=2.0 was rectified, which was divided into 10 steps. Mammary glands pattern (Fluke NA18-220) were examined with CR (26, 28, and 30 kV) by the automatic exposure mode corrected. The exposure values (mAs) were recorded. CR image was diagnosed and evaluated in double blind way by 4 radiologists according to American Collage of Radiology (ACR) standard. Results: Based on the standard of CR automatic exposure with the dose higher than the traditional exposure of film-screen system, the calibration of mammography automatic exposure was accomplished. The test results of the calibrated mode was better than the scoring system of ACR. Conclusions: Comparative study showed improvement in acquiring high-quality image and reduction of radiation dose. The corrected mammography automatic exposure mode might be a better method for clinical use. (authors)

Ultrasonic mammography

International Nuclear Information System (INIS)

Hueneke, B.

1982-01-01

608 women are examined by means of ultrasonic mammography during the period of 1 year. 432 patients were examined with the compound method with the U.I. Octoson, a water tank scanner, and 176 patients with the real time method with a directly connected linear-array-scanner. The following results were obtained at the end of the examination period: In the ultrasonic and also in the X-ray mammogram tumour diameters can be determined with an error rate of +- 30%. In the diagnosing of carcinomas, a significant dependence of the exactness on the sice of the tumour is found for the combination of the five methods tested (clinical examination, X-ray mammography, ultrasonic mammography, thermography, cytology). Classifying the individual methods with regard to their exactness, X-ray mammography ranks in front of ultrasonic mammography. Mastopathic changes in the breast can be screened by means of ultrasonic mammography. The structure of the changes can be determined more exactly than with an X-ray picture which is due to the possibility of differentiating solid and cystic structures. In diagnosing fibro-adenomas and establishing diagnoses on young women with dense gland bodies, ultrasonic mammography is superior to radiology both in the ability of screening a finding of a fibro-adenoma (US=88%, X-ray=75%) and in the possibility of classifying it as ''more benign than malignant''. (orig./MG) [de

A computerized expert system for mammography

International Nuclear Information System (INIS)

Jackson, V.P.; Dines, K.A.; Bassett, L.W.

1988-01-01

The authors have developed a computer-based expert system to aid in the interpretation of mammograms, breast sonograms, and clinical findings. The radiologist enters clinical and image data into the artificial intelligence system and receives a prediction of the etiology of lesions seen on breast imaging studies. This prototype interactive system has undergone preliminary clinical testing and evaluation. Ultimately, a more refined and complex system will be of value in mammography education, for general radiologists without ready access to mammography experts, for paramedical personnel, and for all mammographers in need of a breast imaging database and reporting systems

Screen-film mammography versus full-field digital mammography in a population-based screening program: The Sogn and Fjordane study

International Nuclear Information System (INIS)

Juel, Inger-Marie; Johannessen, Gunnar; Skaane, Per; Roth Hoff, Solveig; Hofvind, Solveig

2010-01-01

Background: Studies comparing analog and digital mammography in breast cancer screening have shown conflicting results. Little is known about the use of digital photon-counting detectors. Purpose: To retrospectively compare performance indicators in screen-film (SFM) and full-field digital mammography (FFDM) using a photon-counting detector in a population-based screening program. Material and Methods: The Norwegian Social Science Data Services approved the study, which was part of the Norwegian Breast Cancer Screening Program. The program invites women aged 50-69 years to two-view mammography biannually. The study period was January 2005 to June 2006 for SFM and August 2006 to December 2007 for FFDM. Independent double reading was performed using a five-point rating scale for probability of cancer. Recalls due to abnormal mammography were retrospectively reviewed by an expert panel. Performance indicators for the two techniques were compared. Attendance rate was 83.6% (7442/8901) for SFM and 82.0% (6932/8451) for FFDM. Results: The recall rate due to abnormal mammography, cancer detection rate and positive predictive value did not differ significantly between SFM and FFDM: recall 2.3% (174/7442) versus 2.4% (168/6932), cancer detection 0.39% (29/7442) versus 0.48% (33/6932), positive predictive value 16.7% (29/174) versus 19.6% (33/168), respectively (P>0.05 for all). The recall rate due to technically inadequate mammograms was 0.3% (19/7442) for SFM and 0.01% (1/6932) for FFDM. In the retrospective review, a significantly higher proportion of calcifications and asymmetric density were categorized as normal or definitively benign in FFDM compared with SFM. The average glandular dose was 2.17 mGy for SFM and 1.25 mGy for FFDM. Conclusion: Performance indicators show that FFDM using photon-counting detector is suitable for breast cancer screening. The lower radiation dose and lower recalls due to technically inadequate mammograms are of importance in mammography

Soft copy digital mammography

International Nuclear Information System (INIS)

Kim, Hak Hee

2005-01-01

Screen-film mammography (SFM) has been the standard method used for breast cancer screening and making a clinical diagnosis. It is a valuable modality for the detection and differentiation of breast calcifications. The advantages are the high spatital resolution, the convenient display, and inexpensiveness. However, it has some inherent limitations such as its low detective quantum efficiency and difficulty of post-processing after obtaining after an image. Digital mammography (DM) has the potential to overcome the inherent limitations of SFM. DM systems directly qualify x-ray photons and decouple the process of x-ray photon detection from the image display. The digital images can be processed by a computer and displayed in multiple formats. Thus, DM is better than SFM for the detection of mass lesions due to its high contrast resolution

Distributed computing feasibility in a non-dedicated homogeneous distributed system

Science.gov (United States)

Leutenegger, Scott T.; Sun, Xian-He

1993-01-01

The low cost and availability of clusters of workstations have lead researchers to re-explore distributed computing using independent workstations. This approach may provide better cost/performance than tightly coupled multiprocessors. In practice, this approach often utilizes wasted cycles to run parallel jobs. The feasibility of such a non-dedicated parallel processing environment assuming workstation processes have preemptive priority over parallel tasks is addressed. An analytical model is developed to predict parallel job response times. Our model provides insight into how significantly workstation owner interference degrades parallel program performance. A new term task ratio, which relates the parallel task demand to the mean service demand of nonparallel workstation processes, is introduced. It was proposed that task ratio is a useful metric for determining how large the demand of a parallel applications must be in order to make efficient use of a non-dedicated distributed system.

Variability of breast density assessment in short-term reimaging with digital mammography

International Nuclear Information System (INIS)

Kim, Won Hwa; Moon, Woo Kyung; Kim, Sun Mi; Yi, Ann; Chang, Jung Min; Koo, Hye Ryoung; Lee, Su Hyun; Cho, Nariya

2013-01-01

Objective: To evaluate the variability of breast density assessments in short-term reimaging with digital mammography. Materials and methods: In 186 women, short term (mean interval, 27.6 days) serial digital mammograms including CC and MLO views were obtained without any treatment. Mammographic density assessments were performed by three blinded radiologists for Breast Imaging Report and Data System (BI-RADS, grades 1–4) and visual percentage density (PD) estimation, and by one radiologist for computer-aided PD estimation. The variability of assessments was analyzed according to the age, breast density, and mammography types by multivariate logistic regression. Results: In BI-RADS assessments, 29% (161 of 558) of breast density categories were assessed differently after short-term reimaging and the mean absolute difference in PD for CC and MLO view was 7.6% and 8.1% for visual assessments, and 7.4% and 6.4% for computer-aided assessments, respectively. Among all computer-aided assessments, 29% (54 of 186) of CC view and 22% (41 of 186) of MLO view assessments had discrepancy over 10% in PD. Younger age (<50), greater breast density (grades 3 and 4), and different mammography types were significantly associated with the variability. Conclusion: Considerable variability in breast density assessments occurred in short-term reimaging with digital mammography, particularly in women with younger age and greater breast density and when examined using different types of mammography

Variability of breast density assessment in short-term reimaging with digital mammography

Energy Technology Data Exchange (ETDEWEB)

Kim, Won Hwa [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Moon, Woo Kyung, E-mail: moonwk@snu.ac.kr [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Sun Mi [Department of Radiology, Seoul National University Bundang Hospital, Gyeonggi-do (Korea, Republic of); Yi, Ann [Department of Radiology, Seoul Metropolitan Government Seoul National University, Boramae Medical Center, Seoul (Korea, Republic of); Chang, Jung Min; Koo, Hye Ryoung; Lee, Su Hyun; Cho, Nariya [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

2013-10-01

Objective: To evaluate the variability of breast density assessments in short-term reimaging with digital mammography. Materials and methods: In 186 women, short term (mean interval, 27.6 days) serial digital mammograms including CC and MLO views were obtained without any treatment. Mammographic density assessments were performed by three blinded radiologists for Breast Imaging Report and Data System (BI-RADS, grades 1–4) and visual percentage density (PD) estimation, and by one radiologist for computer-aided PD estimation. The variability of assessments was analyzed according to the age, breast density, and mammography types by multivariate logistic regression. Results: In BI-RADS assessments, 29% (161 of 558) of breast density categories were assessed differently after short-term reimaging and the mean absolute difference in PD for CC and MLO view was 7.6% and 8.1% for visual assessments, and 7.4% and 6.4% for computer-aided assessments, respectively. Among all computer-aided assessments, 29% (54 of 186) of CC view and 22% (41 of 186) of MLO view assessments had discrepancy over 10% in PD. Younger age (<50), greater breast density (grades 3 and 4), and different mammography types were significantly associated with the variability. Conclusion: Considerable variability in breast density assessments occurred in short-term reimaging with digital mammography, particularly in women with younger age and greater breast density and when examined using different types of mammography.

Computer Simulation of Reading.

Science.gov (United States)

Leton, Donald A.

In recent years, coding and decoding have been claimed to be the processes for converting one language form to another. But there has been little effort to locate these processes in the human learner or to identify the nature of the internal codes. Computer simulation of reading is useful because the similarities in the human reception and…

Digital Mammography in Young Women: Is a Single View Sufficient?

Science.gov (United States)

Gossner, Johannes

2016-03-01

Single view mammography may be a less time consuming, more comfortable and radiation reduced alternative for young women, but there are no studies examining this approach after the implementation of digital mammography into clinical practice. Retrospective analysis of all mammographies performed in women younger than 40 years during a 24 month period. The sample consisted of 109 women with 212 examined breasts. All patients initially received standard two- view mammography. In the study setting the MLO- views were read by a single viewer and compared to a composite reference standard. In this sample 7 malignant findings were present and the review of the MLO-view detected 6 of them (85%). In patients with dense breasts 4 out of 5 malignant findings were found on the single-view (sensitivity 80%) and all 2 malignant findings were detected in patients with low breast density (sensitivity 100%). There were 7 false positive findings (3.3%). i.e. in total 8 out of 212 examined breasts were therefore misinterpreted (3.8%). Single view digital mammography detects the vast majority of malignant findings, especially in low density breast tissue and the rate of false-positive findings is within acceptable limits. Therefore this approach may be used in different scenarios (for example in increasing patient throughout in resource poor settings, reducing radiation burden in the young or in combination with ultrasound to use the strengths of both methods). More research on this topic is needed to establish its potential role in breast imaging.

Helping Children Learn Vocabulary during Computer-Assisted Oral Reading

Directory of Open Access Journals (Sweden)

Gregory Aist

2002-04-01

Full Text Available This paper addresses an indispensable skill using a unique method to teach a critical component: helping children learn to read by using computer-assisted oral reading to help children learn vocabulary. We build on Project LISTEN’s Reading Tutor, a computer program that adapts automatic speech recognition to listen to children read aloud, and helps them learn to read (http://www.cs.cmu.edu/~listen. To learn a word from reading with the Reading Tutor, students must encounter the word and learn the meaning of the word in context. We modified the Reading Tutor first to help students encounter new words and then to help them learn the meanings of new words. We then compared the Reading Tutor to classroom instruction and to human-assisted oral reading as part of a yearlong study with 144 second and third graders. The result: Second graders did about the same on word comprehension in all three conditions. However, third graders who read with the 1999 Reading Tutor, modified as described in this paper, performed statistically significantly better than other third graders in a classroom control on word comprehension gains – and even comparably with other third graders who read one-on-one with human tutors.

Digital mammography: what do we and what don't we know?

International Nuclear Information System (INIS)

Bick, Ulrich; Diekmann, Felix

2007-01-01

High-quality full-field digital mammography has been available now for several years and is increasingly used for both diagnostic and screening mammography. A number of different detector technologies exist, which all have their specific advantages and disadvantages. Diagnostic accuracy of digital mammography has been shown to be at least equivalent to film-screen mammography in a general screening population. Digital mammography is superior to screen-film mammography in younger women with dense breasts due to its ability to selectively optimize contrast in areas of dense parenchyma. This advantage is especially important in women with a genetic predisposition for breast cancer, where intensified early detection programs may have to start from 25 to 30 years of age. Tailored image processing and computer-aided diagnosis hold the potential to further improve the early detection of breast cancer. However, at present no consensus exists among radiologists on which processing is optimal for digital mammograms. Image processing may also vary significantly among vendors with so far limited interoperability. This review aims to summarize the available information regarding the impact of digital mammography on workflow and breast cancer diagnosis. (orig.)

Tomosynthesis and contrast-enhanced digital mammography: recent advances in digital mammography

International Nuclear Information System (INIS)

Diekmann, Felix; Bick, Ulrich

2007-01-01

Digital mammography is more and more replacing conventional mammography. Initial concerns about an inferior image quality of digital mammography have been largely overcome and recent studies even show digital mammography to be superior in women with dense breasts, while at the same time reducing radiation exposure. Nevertheless, an important limitation of digital mammography remains: namely, the fact that summation may obscure lesions in dense breast tissue. However, digital mammography offers the option of so-called advanced applications, and two of these, contrast-enhanced mammography and tomosynthesis, are promising candidates for improving the detection of breast lesions otherwise obscured by the summation of dense tissue. Two techniques of contrast-enhanced mammography are available: temporal subtraction of images acquired before and after contrast administration and the so-called dual-energy technique, which means that pairs of low/high-energy images acquired after contrast administration are subtracted. Tomosynthesis on the other hand provides three-dimensional information on the breast. The images are acquired with different angulations of the X-ray tube while the object or detector is static. Various reconstruction algorithms can then be applied to the set of typically nine to 28 source images to reconstruct 1-mm slices with a reduced risk of obscuring pathology. Combinations of both advanced applications have only been investigated in individual experimental studies; more advanced software algorithms and CAD systems are still in their infancy and have only undergone preliminary clinical evaluation. (orig.)

Determinants of mammography screening behavior in Iranian women: A population-based study

Directory of Open Access Journals (Sweden)

Mitra Moodi

2012-01-01

Full Text Available Background: Breast cancer remains a substantial health concern in Iran due to delay and late stage at diagnosis and treatment. Despite the potential benefits of mammography screening for early detection of breast cancer, the performance of this screening among Iranian women is low. For planning appropriate intervention, this study was carried out to identify mammography rates and explore determinants of mammography screening behavior in females of Isfahan, Iran. Materials and Methods: In this population-based study, 384 women of 40 years and older were interviewed by telephone. The Farsi version of Champion′s Health Belief Model scale (CHBMS was used to examine factors associated with mammography screening. The obtained data were analyzed by SPSS (version 16.0 using statistical Chi-square, Fisher Exact test, t-test and multiple logistic regression model to identify the importance rate of socio-demographic and Health Belief Model (HBM variables to predict mammography screening behavior. In all of tests, the level of significant was considered a = 0.05. Results: Mean age ΁ SD of women was 52.24 ΁ 8.2 years. Of the 384 participants, 44.3% reported at least one mammogram in their lifetime. Logistic regression analysis indicated that women were more likely to have mammography if they heard/read about breast cancer (OR = 4.17, 95% CI 2.09, 8.34, menopause in lower age (OR = 0.2, 95% CI 0.87, 0.99 and history of breast problem (OR = 0.9, 95% CI 0.12, 0.32. Also, women who perceived more benefits of mammography (OR = 1.84, 95% CI 1.63, 2.09, fewer barriers of mammography (OR = 0.91, 95% CI 0.86, 0.96 and had more motivation for health (OR = 0.94, 95% CI 0.89, 1 were more likely to have mammography. Conclusion: The findings indicated that the rate of mammography screening among women in Isfahan province is low and highlights the need for developing a comprehensive national breast cancer control program, which should be considered as the first

High-speed large angle mammography tomosynthesis system

Science.gov (United States)

Eberhard, Jeffrey W.; Staudinger, Paul; Smolenski, Joe; Ding, Jason; Schmitz, Andrea; McCoy, Julie; Rumsey, Michael; Al-Khalidy, Abdulrahman; Ross, William; Landberg, Cynthia E.; Claus, Bernhard E. H.; Carson, Paul; Goodsitt, Mitchell; Chan, Heang-Ping; Roubidoux, Marilyn; Thomas, Jerry A.; Osland, Jacqueline

2006-03-01

A new mammography tomosynthesis prototype system that acquires 21 projection images over a 60 degree angular range in approximately 8 seconds has been developed and characterized. Fast imaging sequences are facilitated by a high power tube and generator for faster delivery of the x-ray exposure and a high speed detector read-out. An enhanced a-Si/CsI flat panel digital detector provides greater DQE at low exposure, enabling tomo image sequence acquisitions at total patient dose levels between 150% and 200% of the dose of a standard mammographic view. For clinical scenarios where a single MLO tomographic acquisition per breast may replace the standard CC and MLO views, total tomosynthesis breast dose is comparable to or below the dose in standard mammography. The system supports co-registered acquisition of x-ray tomosynthesis and 3-D ultrasound data sets by incorporating an ultrasound transducer scanning system that flips into position above the compression paddle for the ultrasound exam. Initial images acquired with the system are presented.

Clear-PEM: A dedicated PET camera for improved breast cancer detection

International Nuclear Information System (INIS)

Abreu, M. C.; Almeida, P.; Balau, F.; Ferreira, N. C.; Fetal, S.; Fraga, F.; Martins, M.; Matela, N.; Moura, R.; Ortigao, C.; Peralta, L.; Rato, P.; Ribeiro, R.; Rodrigues, P.; Santos, A. I.; Trindade, A.; Varela, J.

2005-01-01

Positron emission mammography (PEM) can offer a non-invasive method for the diagnosis of breast cancer. Metabolic images from PEM using 18 F-fluoro-deoxy-glucose, contain unique information not available from conventional morphologic imaging techniques like X-ray radiography. In this work, the concept of Clear-PEM, the system presently developed in the frame of the Crystal Clear Collaboration at CERN, is described. Clear-PEM will be a dedicated scanner, offering better perspectives in terms of position resolution and detection sensitivity. (authors)

Comparison between film-screen and computed radiography systems in Brazilian mammography

International Nuclear Information System (INIS)

Vieira, L.A.; Oliveira, J.R.; Carvalho, L.A.P.; César, A.C.Z.; Nogueira, M.S.

2015-01-01

Since 2004 the Public Health Office of the State of Minas Gerais in Brazil has established the Image Quality Control Program in Mammography. It evaluates the image quality based on an accredited phantom of the Brazilian College of Radiology (CBR). This phantom follows international standards such as masses, specks, fibers, contrast details and spatial resolution. The contrast index (CI) is accessed through optical density (OD) measurements. Although OD is defined under film-screen (FS) scope, among all accessible mammographic systems under the health office surveillance, almost 80% are computed radiography (CR) based. A necessity to adapt the protocol has emerged to consider OD as a conformity parameter. Objective: To verify the OD accessibility under CR´s printed out films and the feasibility to calculate contrast index, in comparison with FS´s. Results: A total of 56 images were evaluated with three different CBR phantoms. They were equally divided into FS and CR systems and a densitometer was used to read out their OD values. The correlation between their contrast-to-noise ratio (CNR) was found to be in the order of 0.77 (±0.14). The samples were not significantly different (inside 5% incertitude) for every phantom. The CNR correlation coefficient was 0.871. For OD, correlation coefficient was 0.989 and a log-fit function has shown good agreement with detector response. The OD-normalized standard deviation difference between CR and FS for every different phantom was 36.6%, 2.8% and 20.2%. A CI range for CR´s lying between 0.13 and 0.69 was found. Conclusions: Different phantoms were successfully tested in both CR and FS to evaluate the feasibility in use contrast index as a conformity parameter since their correlations are strictly related to calibration curve, as provided by phantom manufacturer. The relative CR-FS OD σ-difference provides a spreading indicator, where the first and last phantoms are considerably out of expectation. Such differences are

Incorporating Computers into Classroom: Effects on Learners’ Reading Comprehension in EFL Context

Directory of Open Access Journals (Sweden)

Ali Akbar Ansarin

2017-10-01

Full Text Available Owing to the importance of computer-assisted reading and considering the prominent role of learners in this respect, the present study investigated: (1 the effects of computer as a supplemental tool to support and improve the Iranian EFL learners’ reading comprehension in comparison with equivalent non-technological or traditional print-based treatments, (2 EFL learners’ attitudes and perception towards the computer-assisted reading course.To this purpose, 111 randomly selected groups of EFL learners participated in the study. The subjects were divided into two groups of control and experimental. Both groups received 10 reading lessons either through computers or through an instructor-led method. The statistical analysis revealed no significant difference between the learners who had access to reading supports on computer screen and their counterparts in the traditional reading classes. Learners were also allowed to express their ideas on a 5-point Likert Scale. The purpose of the attitude questionnaire was to find out more information about the participants and their experiences with computer-assisted reading. Results of attitude questionnaire supported the conclusion that computers may enhance EFL learners’ motivation and interest towards learning but they do not enhance comprehension. The findings of this study support the view that technology should supplement not supplant teachers and that people read less accurately and less comprehensively on screens than on paper.

A comparison of the performance of modern screen-film and digital mammography systems

Energy Technology Data Exchange (ETDEWEB)

Monnin, P [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Gutierrez, D [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Bulling, S [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Lepori, D [Department of Radiology, University Hospital Center (CHUV), CH-1011 Lausanne (Switzerland); Valley, J-F [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Verdun, F R [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland)

2005-06-07

This work compares the detector performance and image quality of the new Kodak Min-R EV mammography screen-film system with the Fuji CR Profect detector and with other current mammography screen-film systems from Agfa, Fuji and Kodak. Basic image quality parameters (MTF, NPS, NEQ and DQE) were evaluated for a 28 kV Mo/Mo (HVL = 0.646 mm Al) beam using different mAs exposure settings. Compared with other screen-film systems, the new Kodak Min-R EV detector has the highest contrast and a low intrinsic noise level, giving better NEQ and DQE results, especially at high optical density. Thus, the properties of the new mammography film approach those of a fine mammography detector, especially at low frequency range. Screen-film systems provide the best resolution. The presampling MTF of the digital detector has a value of 15% at the Nyquist frequency and, due to the spread size of the laser beam, the use of a smaller pixel size would not permit a significant improvement of the detector resolution. The dual collection reading technology increases significantly the low frequency DQE of the Fuji CR system that can at present compete with the most efficient mammography screen-film systems.

Radiation doses and some aspects of image quality in mammography facilities in New Zealand

International Nuclear Information System (INIS)

Williamson, B.D.P.; Poletti, J.L.

1990-02-01

Until recently, mammography in New Zealand was performed largely with adapted conventional x-ray machines with tungsten anode x-ray tubes. Over the last several years these have virtually all been replaced by dedicated mammography machines with molybdenum anode x-ray tubes. To assess current trends in radiation doses to patients and central aspects of image quality, some 37 mammography x-ray machines were surveyed during 1988-89. The mean glandular dose per film for 30 and 45 mm thick breast-equivalent phantoms was determined using thermoluminescent dosimetry. Imagings of simulated microcalcifications (specks) and a contrast-detail phantom were assessed. Accuracy of calibration of the x-ray machines and quality of film processing were also tested. Details of the survey results are given. Mean glandular tissue doses per cranio-caudal films were generally well within the recommended guidelines. Mammography facilities differed in their ability to delete simulated calcification specks. Mammographic equipment was found to be generally well adjusted. Speed and contrast of film processing were found to vary widely implying that this is a major cause of the variations in dose and image quality. An annex outlines a quality assurance programme for maintenance of optimal physical image quality and control of radiation doses. 55 refs., 21 tabs., 17 figs., 2 ills

MO-AB-207-04: ACR Update in Mammography

International Nuclear Information System (INIS)

Berns, E.

2015-01-01

A goal of an imaging accreditation program is to ensure adequate image quality, verify appropriate staff qualifications, and to assure patient and personnel safety. Currently, more than 35,000 facilities in 10 modalities have been accredited by the American College of Radiology (ACR), making the ACR program one of the most prolific accreditation options in the U.S. In addition, ACR is one of the accepted accreditations required by some state laws, CMS/MIPPA insurance and others. Familiarity with the ACR accreditation process is therefore essential to clinical diagnostic medical physicists. Maintaining sufficient knowledge of the ACR program must include keeping up-to-date as the various modality requirements are refined to better serve the goals of the program and to accommodate newer technologies and practices. This session consists of presentations from authorities in four ACR accreditation modality programs, including magnetic resonance imaging, computed tomography, nuclear medicine, and mammography. Each speaker will discuss the general components of the modality program and address any recent changes to the requirements. Learning Objectives: To understand the requirements of the ACR MR Accreditation program. The discussion will include accreditation of whole-body general purpose magnets, dedicated extremity systems well as breast MRI accreditation. Anticipated updates to the ACR MRI Quality Control Manual will also be reviewed. To understand the requirements of the ACR CT accreditation program, including updates to the QC manual as well as updates through the FAQ process. To understand the requirements of the ACR nuclear medicine accreditation program, and the role of the physicist in annual equipment surveys and the set up and supervision of the routine QC program. To understand the current ACR MAP Accreditation requirement and present the concepts and structure of the forthcoming ACR Digital Mammography QC Manual and Program

MO-AB-207-04: ACR Update in Mammography

Energy Technology Data Exchange (ETDEWEB)

Berns, E. [University of Colorado Health Science (United States)

2015-06-15

A goal of an imaging accreditation program is to ensure adequate image quality, verify appropriate staff qualifications, and to assure patient and personnel safety. Currently, more than 35,000 facilities in 10 modalities have been accredited by the American College of Radiology (ACR), making the ACR program one of the most prolific accreditation options in the U.S. In addition, ACR is one of the accepted accreditations required by some state laws, CMS/MIPPA insurance and others. Familiarity with the ACR accreditation process is therefore essential to clinical diagnostic medical physicists. Maintaining sufficient knowledge of the ACR program must include keeping up-to-date as the various modality requirements are refined to better serve the goals of the program and to accommodate newer technologies and practices. This session consists of presentations from authorities in four ACR accreditation modality programs, including magnetic resonance imaging, computed tomography, nuclear medicine, and mammography. Each speaker will discuss the general components of the modality program and address any recent changes to the requirements. Learning Objectives: To understand the requirements of the ACR MR Accreditation program. The discussion will include accreditation of whole-body general purpose magnets, dedicated extremity systems well as breast MRI accreditation. Anticipated updates to the ACR MRI Quality Control Manual will also be reviewed. To understand the requirements of the ACR CT accreditation program, including updates to the QC manual as well as updates through the FAQ process. To understand the requirements of the ACR nuclear medicine accreditation program, and the role of the physicist in annual equipment surveys and the set up and supervision of the routine QC program. To understand the current ACR MAP Accreditation requirement and present the concepts and structure of the forthcoming ACR Digital Mammography QC Manual and Program.

Mammography and radiation risk; Mammographie und Strahlenrisiko

Energy Technology Data Exchange (ETDEWEB)

Jung, H. [Hamburg Univ. (Germany). Inst. fuer Biophysik und Strahlenbiologie

1998-10-01

Breast cancer is the most frequent malignant neoplasia among women in Germany. The use of mammography as the most relevant diagnostic procedure has increased rapidly over the last decade. Radiation risks associated with mammography may be estimated from the results of numerous epidemiological studies providing risk coefficients for breast cancer in relation to age at exposure. Various calculations can be performed using the risk coefficients. For instance, a single mammography examination (bilateral, two views of each breast) of a women aged 45 may enhance the risk of developing breast cancer during her lifetime numerically from about 12% of 12.0036%. This increase in risk is lower by a factor of 3,300 as compared to the risk of developing breast cancer in the absence of radiation exposure. At the age of 40 or more, the benefit of mammography exceeds the radiation risk by a factor of about 100. At higher ages this factor increases further. Finally, the dualism of individual risk and collective risk is considered. It is shown that the individual risk of a patient, even after multiple mammography examinations, is vanishingly small. Nevertheless, the basic principle of minimising radiation exposure must be followed to keep the collective risk in the total population as low as reasonably achievable. (orig.) [Deutsch] Das Mammakarzinom ist in Deutschland die haeufigste Krebserkrankung der Frau, und entsprechend oft wird die Mammographie als das derzeit wichtigste Diagnoseverfahren eingesetzt. Zur Beurteilung des mit einer mammographischen Untersuchung verbundenen Strahlenrisikos liegen die Resultate einer groesseren Anzahl strahlenepidemiologischer Studien vor. Diese liefern den Risikokoeffizienten fuer Brustkrebs in Abhaengigkeit vom Lebensalter bei Strahlenexposition und ermoeglichen somit die Berechnung des altersabhaengigen Strahlenrisikos. Beispielsweise wird durch eine einmalige Mammographie-Untersuchung (bilateral, je zwei Aufnahmen in zwei Ebenen) bei einer 45

The Relationship between Computer Games and Reading Achievement

Science.gov (United States)

Reed, Tammy Dotson

2010-01-01

Illiteracy rates are increasing. The negative social and economic effects caused by weak reading skills include political unrest, social and health service inequality, poverty, and employment challenges. This quantitative study explored the proposition that the use of computer software games would increase reading achievement in second grade…

Study of signal-to-noise ratio in digital mammography

Science.gov (United States)

Kato, Yuri; Fujita, Naotoshi; Kodera, Yoshie

2009-02-01

Mammography techniques have recently advanced from those using analog systems (the screen-film system) to those using digital systems; for example, computed radiography (CR) and flat-panel detectors (FPDs) are nowadays used in mammography. Further, phase contrast mammography (PCM)-a digital technique by which images with a magnification of 1.75× can be obtained-is now available in the market. We studied the effect of the air gap in PCM and evaluated the effectiveness of an antiscatter x-ray grid in conventional mammography (CM) by measuring the scatter fraction ratio (SFR) and relative signal-to-noise ratio (rSNR) and comparing them between PCM and the digital CM. The results indicated that the SFRs for the CM images obtained with a grid were the lowest and that these ratios were almost the same as those for the PCM images. In contrast, the rSNRs for the PCM images were the highest, which means that the scattering of x-rays was sufficiently reduced by the air gap without the loss of primary x-rays.

Interpretation of digital breast tomosynthesis: preliminary study on comparison with picture archiving and communication system (PACS) and dedicated workstation.

Science.gov (United States)

Kim, Young Seon; Chang, Jung Min; Yi, Ann; Shin, Sung Ui; Lee, Myung Eun; Kim, Won Hwa; Cho, Nariya; Moon, Woo Kyung

2017-08-01

To compare the diagnostic accuracy and efficiency in the interpretation of digital breast tomosynthesis (DBT) images using a picture archiving and communication system (PACS) and a dedicated workstation. 97 DBT images obtained for screening or diagnostic purposes were stored in both a workstation and a PACS and evaluated in combination with digital mammography by three independent radiologists retrospectively. Breast Imaging-Reporting and Data System final assessments and likelihood of malignancy (%) were assigned and the interpretation time when using the workstation and PACS was recorded. Receiver operating characteristic curve analysis, sensitivities and specificities were compared with histopathological examination and follow-up data as a reference standard. Area under the receiver operating characteristic curve values for cancer detection (0.839 vs 0.815, p = 0.6375) and sensitivity (81.8% vs 75.8%, p = 0.2188) showed no statistically significant differences between the workstation and PACS. However, specificity was significantly higher when analysing on the workstation than when using PACS (83.7% vs 76.9%, p = 0.009). When evaluating DBT images using PACS, only one case was deemed necessary to be reanalysed using the workstation. The mean time to interpret DBT images on PACS (1.68 min/case) was significantly longer than that to interpret on the workstation (1.35 min/case) (p < 0.0001). Interpretation of DBT images using PACS showed comparable diagnostic performance to a dedicated workstation, even though it required a longer reading time. Advances in knowledge: Interpretation of DBT images using PACS is an alternative to evaluate the images when a dedicated workstation is not available.

Impacts of Watching Television and Computer Using on Student' Reading Habits

Directory of Open Access Journals (Sweden)

Ayşe Gül Aksaçlıoğlu

2013-11-01

Full Text Available Reading habits contribute both to the cognitive and social developments of indi- viduals in so many aspects. This function of the reading habit continues in the rapid social changing process of today’s world. However, children’s habits of te- levision watching and computer using have been recently seen to affect their reading habits. Therefore, defining the positive or negative impacts of television and computers on children and finding solutions carries significant importance. The aim of this study is to determine the influences of the television watching and computer using on children’s reading habits. In order to find out the influ- ences, a survey was performed on all 5th grade students at Bilkent Private Primary School and Çankaya Public Primary School located within Ankara Büyükþehir Municipality borders. The questionaire was applied to 222 students in these two schools. As a result of the study, it is clear that students prefer to play on com- puters and watch television in their leisure time to reading books. There is an inverse proportion apparent between the time spent using computers and watching television and the time spent on reading.

Experience with digital mammography

Directory of Open Access Journals (Sweden)

G. P. Korzhenkova

2011-01-01

Full Text Available The use of digital techniques in mammography has become a last step for completing the process of digitization in diagnostic imaging. It is assumed that such a spatial decision will be required for digital mammography, as well as for high-resolution intensifying screen-film systems used in conventional mammography and that the digital techniques will be limited by the digitizer pixel size on detecting minor structures, such as microcalcifications. The introduction of digital technologies in mammography involves a tight control over an image and assures its high quality.

Deep learning in mammography and breast histology, an overview and future trends.

Science.gov (United States)

Hamidinekoo, Azam; Denton, Erika; Rampun, Andrik; Honnor, Kate; Zwiggelaar, Reyer

2018-07-01

Recent improvements in biomedical image analysis using deep learning based neural networks could be exploited to enhance the performance of Computer Aided Diagnosis (CAD) systems. Considering the importance of breast cancer worldwide and the promising results reported by deep learning based methods in breast imaging, an overview of the recent state-of-the-art deep learning based CAD systems developed for mammography and breast histopathology images is presented. In this study, the relationship between mammography and histopathology phenotypes is described, which takes biological aspects into account. We propose a computer based breast cancer modelling approach: the Mammography-Histology-Phenotype-Linking-Model, which develops a mapping of features/phenotypes between mammographic abnormalities and their histopathological representation. Challenges are discussed along with the potential contribution of such a system to clinical decision making and treatment management. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

Magnification mammography: a comparison of full-field digital mammography and screen-film mammography for the detection of simulated small masses and microcalcifications

International Nuclear Information System (INIS)

Hermann, K.P.; Obenauer, S.; Funke, M.; Grabbe, E.H.

2002-01-01

The objective of this study was a comparison of a full-field digital mammography (FFDM) system and a conventional screen-film mammography (SFM) system with respect to the detectability of simulated small masses and microcalcifications in the magnification mode. All images were obtained using 1.8 times magnification. The FFDM images were obtained at radiation dose levels of 1.39, 1.0, 0.7, 0.49 and 0.24 times that of the SFM images. A contrast-detail phantom was used to compare the detection of simulated lesions using a four alternative forced-choice reader study with three readers. The correct observation ratio (COR) was calculated as the fraction of correctly identified lesions to the total number of simulated lesions. Soft-copy reading was performed for all digital images. Direct magnification images acquired with the digital system showed a lower object contrast threshold than those acquired with the conventional system. For equal radiation dose, the digital system provided a significantly increased COR (0.95) compared with the screen-film system (0.82). For simulated microcalcifications, the corresponding difference was 0.90 to 0.72. The digital system allowed equal detection to screen-film at 40% of the radiation dose used for screen film. Digital magnification images are superior to screen-film magnification images for the detection of simulated small masses and microcalcifications even at a lower radiation dose. (orig.)

Thyroid absorbed dose using TLDs during mammography

International Nuclear Information System (INIS)

Gonzalez A, M.; Melendez L, M.; Davila M, P.

2015-10-01

Full text: In this study, the mean glandular dose (MGD) and the thyroid dose (D Thy) were measured in 200 women screened with mammography in Cranio caudal (Cc) and mediolateral oblique projections. All mammograms were performed with Giotto-Ims (6000-14-M2 Model) equipment, which was verified to meet the criteria of quality of NOM-229-Ssa-2002. During audits performance and HVL, for each anode filter combinations was measured with the camera Radcal mammography equipment 10 X 6-6M (HVL = 0.26 mm Al). D Thy measurements were performed with TLD dosimeters (LiF:Mn) , that were read with the Harshaw 3500 TLD reader. The MGD, was obtained according to the UK and European protocols for mammographic dosimetry using a plane parallel chamber (Standard Imaging, Model A-600) calibrated by a radiation beam UW-23-Mo (= 0.279 mm Al HVL). A comparative statistical analysis was carried out with the measured MGD and D thy. The thyroid mean dose was 0.063 mGy and 0.078 mGy for Cc and mediolateral oblique respectively. There is a linear correlation between the MGD and the D Thy slightly influenced by the anode-filter combination. Using a 95% for the confidence interval in MGD (1.07 mGy), the 90% of measurements are in agreement with the established uncertainty limits. The D Thy are lower than the MGD. There is no risk for cancer induction in thyroid in women due to mammography screening. (Author)

Monte Carlo derivation of filtered tungsten anode X-ray spectra for dose computation in digital mammography

Energy Technology Data Exchange (ETDEWEB)

Paixao, L.; Oliveira, B. B.; Nogueira, M. do S. [Centro de Desenvolvimento da Tecnologia Nuclear, Post-graduation in Science and Technology of Radiations, Minerals and Materials, Pte. Antonio Carlos 6.627, Pampulha, 31270-901 Belo Horizonte (Brazil); Viloria, C. [UFMG, Departamento de Engenharia Nuclear, Post-graduation in Nuclear Sciences and Techniques, Pte. Antonio Carlos 6.627, Pampulha, 31270-901 Belo Horizonte (Brazil); Alves de O, M. [UFMG, Department of Anatomy and Imaging, Prof. Alfredo Balena 190, 30130-100 Belo Horizonte (Brazil); Araujo T, M. H., E-mail: lpr@cdtn.br [Dr Maria Helena Araujo Teixeira Clinic, Guajajaras 40, 30180-100 Belo Horizonte (Brazil)

2014-08-15

It is widely accepted that the mean glandular dose (D{sub G}) for the glandular tissue is the more useful magnitude for characterizing the breast cancer risk. The procedure to estimate the D{sub G}, for being difficult to measure it directly in the breast, it is to make the use of conversion factors that relate incident air kerma (K{sub i}) at this dose. Generally, the conversion factors vary with the x-ray spectrum half-value layer and the breast composition and thickness. Several authors through computer simulations have calculated such factors by the Monte Carlo (Mc) method. Many spectral models for D{sub G} computer simulations purposes are available in the diagnostic range. One of the models available generates unfiltered spectra. In this work, the Monte Carlo EGSnrc code package with the C++ class library (eg spp) was employed to derive filtered tungsten x-ray spectra used in digital mammography systems. Filtered spectra for rhodium and aluminium filters were obtained for tube potentials between 26 and 32 kV. The half-value layer of simulated filtered spectra were compared with those obtained experimentally with a solid state detector Unfors model 8202031-H Xi R/F and Mam Detector Platinum and 8201023-C Xi Base unit Platinum Plus w m As in a Hologic Selenia Dimensions system using a Direct Radiography mode. Calculated half-value layer values showed good agreement compared to those obtained experimentally. These results show that the filtered tungsten anode x-ray spectra and the EGSnrc Mc code can be used for D{sub G} determination in mammography. (Author)

Monte Carlo derivation of filtered tungsten anode X-ray spectra for dose computation in digital mammography

International Nuclear Information System (INIS)

Paixao, L.; Oliveira, B. B.; Nogueira, M. do S.; Viloria, C.; Alves de O, M.; Araujo T, M. H.

2014-08-01

It is widely accepted that the mean glandular dose (D G ) for the glandular tissue is the more useful magnitude for characterizing the breast cancer risk. The procedure to estimate the D G , for being difficult to measure it directly in the breast, it is to make the use of conversion factors that relate incident air kerma (K i ) at this dose. Generally, the conversion factors vary with the x-ray spectrum half-value layer and the breast composition and thickness. Several authors through computer simulations have calculated such factors by the Monte Carlo (Mc) method. Many spectral models for D G computer simulations purposes are available in the diagnostic range. One of the models available generates unfiltered spectra. In this work, the Monte Carlo EGSnrc code package with the C++ class library (eg spp) was employed to derive filtered tungsten x-ray spectra used in digital mammography systems. Filtered spectra for rhodium and aluminium filters were obtained for tube potentials between 26 and 32 kV. The half-value layer of simulated filtered spectra were compared with those obtained experimentally with a solid state detector Unfors model 8202031-H Xi R/F and Mam Detector Platinum and 8201023-C Xi Base unit Platinum Plus w m As in a Hologic Selenia Dimensions system using a Direct Radiography mode. Calculated half-value layer values showed good agreement compared to those obtained experimentally. These results show that the filtered tungsten anode x-ray spectra and the EGSnrc Mc code can be used for D G determination in mammography. (Author)

Computed tomography of the breast: a valuable adjunct to mammography in selected cases

International Nuclear Information System (INIS)

Van Gelderen, W.F.C.; Tygerberg Hospital, Cape Town

1995-01-01

Computed tomography (CT) is not often used for the further assessment of a mass in the breast. In the case presented it proved to be invaluable in demonstrating a very posterior breast mass previously sub optimally demonstrated a mammography, not palpable clinically, and not visualized on ultrasound examination. The predicament of a very posterior breast mass is highlighted and it is suggested that present-day routine cranio-caudal and oblique views may not be adequate to show such a mass even if meticulous attention to radiograph technique is given. If the supine-oblique view with balloon compression cannot be obtained, CT in the prone position with the breasts dependent may be the best alternative. Fine needle aspiration biopsy can be performed under CT guidance in such cases. 4 refs., 3 figs

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

International Nuclear Information System (INIS)

Kim, Min Jung; Kim, Eun-Kyung; Kwak, Jin Young; Son, Eun Ju; Youk, Ji Hyun; Choi, Seon Hyeong; Oh, Ki Keun; Han, Mooyoung

2009-01-01

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. (orig.)

Practical digital mammography

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, Beverly E. [Washington Univ., Seattle, WA (United States)]|[Virginia Mason Medical Center, VA (United States)

2008-07-01

This book is meant for the radiologist who is facing the challenge of organizing a digital mammographic imaging center. This text is meant to be a practical book that provides information about digital mammographic physics and equipment which will allow one to intelligently compare technologies and systems. Some of the major challenges include: large expense; rapidly changing technology, and inconsistent connectivity; and finally, need for strong information technology support. The initial conversion cost to digital mammographic imaging is relatively expensive due to the cost of digital mammography hardware, software, and storage. Virtually all other imaging modalities are being converted to purely digital storage and transfer, and the digital trend in mammography is inevitable. Technical advantages of digital mammography are described. However, the improved flexibility in image display and transfer are some of its strongest features. In conclusion, although there are increasing imaging modalities that may be used to evaluate breast disease, mammography will continue to play a key role in detecting breast cancer. To be an effective imager, the radiologist should become familiar with digital mammography and understand its role within the increasing complex structure of breast imaging techniques.

Practical digital mammography

International Nuclear Information System (INIS)

Hashimoto, Beverly E.

2008-01-01

This book is meant for the radiologist who is facing the challenge of organizing a digital mammographic imaging center. This text is meant to be a practical book that provides information about digital mammographic physics and equipment which will allow one to intelligently compare technologies and systems. Some of the major challenges include: large expense; rapidly changing technology, and inconsistent connectivity; and finally, need for strong information technology support. The initial conversion cost to digital mammographic imaging is relatively expensive due to the cost of digital mammography hardware, software, and storage. Virtually all other imaging modalities are being converted to purely digital storage and transfer, and the digital trend in mammography is inevitable. Technical advantages of digital mammography are described. However, the improved flexibility in image display and transfer are some of its strongest features. In conclusion, although there are increasing imaging modalities that may be used to evaluate breast disease, mammography will continue to play a key role in detecting breast cancer. To be an effective imager, the radiologist should become familiar with digital mammography and understand its role within the increasing complex structure of breast imaging techniques

Automated daily quality control analysis for mammography in a multi-unit imaging center.

Science.gov (United States)

Sundell, Veli-Matti; Mäkelä, Teemu; Meaney, Alexander; Kaasalainen, Touko; Savolainen, Sauli

2018-01-01

Background The high requirements for mammography image quality necessitate a systematic quality assurance process. Digital imaging allows automation of the image quality analysis, which can potentially improve repeatability and objectivity compared to a visual evaluation made by the users. Purpose To develop an automatic image quality analysis software for daily mammography quality control in a multi-unit imaging center. Material and Methods An automated image quality analysis software using the discrete wavelet transform and multiresolution analysis was developed for the American College of Radiology accreditation phantom. The software was validated by analyzing 60 randomly selected phantom images from six mammography systems and 20 phantom images with different dose levels from one mammography system. The results were compared to a visual analysis made by four reviewers. Additionally, long-term image quality trends of a full-field digital mammography system and a computed radiography mammography system were investigated. Results The automated software produced feature detection levels comparable to visual analysis. The agreement was good in the case of fibers, while the software detected somewhat more microcalcifications and characteristic masses. Long-term follow-up via a quality assurance web portal demonstrated the feasibility of using the software for monitoring the performance of mammography systems in a multi-unit imaging center. Conclusion Automated image quality analysis enables monitoring the performance of digital mammography systems in an efficient, centralized manner.

Calibration of a dedicated software for 3D rendering

Energy Technology Data Exchange (ETDEWEB)

Abrantes, Marcos E.S.; Felix, Warley F.; Veloso, Maria Auxiliadora F., E-mail: marcos.nuclear@yahoo.com.br, E-mail: warleyferreirafelix@gmail.com, E-mail: mdora@nuclear.ufmg.br [Faculdade Ciencias Medicas de Minas Gerais (FCMMG), Belo Horizonte, MG (Brazil); Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2017-11-01

With the increasing use of 3D reconstruction techniques, to assist in diagnosis, dedicated programs are being widely used. For this they must be calibrated in order to encounter the values of the real volumes of the human tissues. The purpose of this work is to indicate correction and calibration values for true volumes, read in a 3D reconstruction system dedicated, using DICOM images of Computed Tomography. This work utilized a PMMA thorax phantom associated with the DICOM image and the volume found by a program of a tomograph. The physical volume of the PMMA phantom found was 10359.0 cm³. For the volumes found according to the structures of interest, the values are 11005.5 cm³, 10249.3 cm³ and 10205.1 cm³ and the correction values are -6.2%, +1.1% e +1.5% respectively for tissues: pulmonary, bony and soft tissues. The procedure performed can be used for calibration in other 3D reconstruction programs, observing the necessary corrections and the methodology used. (author)

Calibration of a dedicated software for 3D rendering

International Nuclear Information System (INIS)

Abrantes, Marcos E.S.; Felix, Warley F.; Veloso, Maria Auxiliadora F.; Universidade Federal de Minas Gerais

2017-01-01

With the increasing use of 3D reconstruction techniques, to assist in diagnosis, dedicated programs are being widely used. For this they must be calibrated in order to encounter the values of the real volumes of the human tissues. The purpose of this work is to indicate correction and calibration values for true volumes, read in a 3D reconstruction system dedicated, using DICOM images of Computed Tomography. This work utilized a PMMA thorax phantom associated with the DICOM image and the volume found by a program of a tomograph. The physical volume of the PMMA phantom found was 10359.0 cm³. For the volumes found according to the structures of interest, the values are 11005.5 cm³, 10249.3 cm³ and 10205.1 cm³ and the correction values are -6.2%, +1.1% e +1.5% respectively for tissues: pulmonary, bony and soft tissues. The procedure performed can be used for calibration in other 3D reconstruction programs, observing the necessary corrections and the methodology used. (author)

Baseline Screening Mammography: Performance of Full-Field Digital Mammography Versus Digital Breast Tomosynthesis.

Science.gov (United States)

McDonald, Elizabeth S; McCarthy, Anne Marie; Akhtar, Amana L; Synnestvedt, Marie B; Schnall, Mitchell; Conant, Emily F

2015-11-01

Baseline mammography studies have significantly higher recall rates than mammography studies with available comparison examinations. Digital breast tomosynthesis reduces recalls when compared with digital mammographic screening alone, but many sites operate in a hybrid environment. To maximize the effect of screening digital breast tomosynthesis with limited resources, choosing which patient populations will benefit most is critical. This study evaluates digital breast tomosynthesis in the baseline screening population. Outcomes were compared for 10,728 women who underwent digital mammography screening, including 1204 (11.2%) baseline studies, and 15,571 women who underwent digital breast tomosynthesis screening, including 1859 (11.9%) baseline studies. Recall rates, cancer detection rates, and positive predictive values were calculated. Logistic regression estimated the odds ratios of recall for digital mammography versus digital breast tomosynthesis for patients undergoing baseline screening and previously screened patients, adjusted for age, race, and breast density. In the baseline subgroup, recall rates for digital mammography and digital breast tomosynthesis screening were 20.5% and 16.0%, respectively (p = 0.002); digital breast tomosynthesis screening in the baseline subgroup resulted in a 22% reduction in recall compared with digital mammography, or 45 fewer patients recalled per 1000 patients screened. Digital breast tomosynthesis screening in the previously screened patients resulted in recall reduction of 14.3% (p tomosynthesis than from digital mammography alone.

Comparison of tomosynthesis plus digital mammography and digital mammography alone for breast cancer screening.

Science.gov (United States)

Haas, Brian M; Kalra, Vivek; Geisel, Jaime; Raghu, Madhavi; Durand, Melissa; Philpotts, Liane E

2013-12-01

To compare screening recall rates and cancer detection rates of tomosynthesis plus conventional digital mammography to those of conventional digital mammography alone. All patients presenting for screening mammography between October 1, 2011, and September 30, 2012, at four clinical sites were reviewed in this HIPAA-compliant retrospective study, for which the institutional review board granted approval and waived the requirement for informed consent. Patients at sites with digital tomosynthesis were offered screening with digital mammography plus tomosynthesis. Patients at sites without tomosynthesis underwent conventional digital mammography. Recall rates were calculated and stratified according to breast density and patient age. Cancer detection rates were calculated and stratified according to the presence of a risk factor for breast cancer. The Fisher exact test was used to compare the two groups. Multivariate logistic regression was used to assess the effect of screening method, breast density, patient age, and cancer risk on the odds of recall from screening. A total of 13 158 patients presented for screening mammography; 6100 received tomosynthesis. The overall recall rate was 8.4% for patients in the tomosynthesis group and 12.0% for those in the conventional mammography group (P tomosynthesis reduced recall rates for all breast density and patient age groups, with significant differences (P tomosynthesis versus 5.2 per 1000 in patients receiving conventional mammography alone (P = .70). Patients undergoing tomosynthesis plus digital mammography had significantly lower screening recall rates. The greatest reductions were for those younger than 50 years and those with dense breasts. A nonsignificant 9.5% increase in cancer detection was observed in the tomosynthesis group. © RSNA, 2013.

Artificial Neural Networks in Mammography Interpretation and Diagnostic Decision Making

Directory of Open Access Journals (Sweden)

Turgay Ayer

2013-01-01

Full Text Available Screening mammography is the most effective means for early detection of breast cancer. Although general rules for discriminating malignant and benign lesions exist, radiologists are unable to perfectly detect and classify all lesions as malignant and benign, for many reasons which include, but are not limited to, overlap of features that distinguish malignancy, difficulty in estimating disease risk, and variability in recommended management. When predictive variables are numerous and interact, ad hoc decision making strategies based on experience and memory may lead to systematic errors and variability in practice. The integration of computer models to help radiologists increase the accuracy of mammography examinations in diagnostic decision making has gained increasing attention in the last two decades. In this study, we provide an overview of one of the most commonly used models, artificial neural networks (ANNs, in mammography interpretation and diagnostic decision making and discuss important features in mammography interpretation. We conclude by discussing several common limitations of existing research on ANN-based detection and diagnostic models and provide possible future research directions.

Dose and risk evaluation in digital mammography using computer modeling

Energy Technology Data Exchange (ETDEWEB)

Correa, Samanda Cristine Arruda; Souza, Edmilson Monteiro de, E-mail: scorrea@nuclear.ufrj.b, E-mail: emonteiro@nuclear.ufrj.b [Centro Universitario Estadual da Zona Oeste (CCMAT/UEZO), Rio de Janeiro, RJ (Brazil); Silva, Humberto de Oliveira, E-mail: hbetorj@gmail.co [Universidade Federal do Rio de Janeiro IF/UFRJ, RJ (Brazil). Inst. de Fisica; Silva, Ademir Xavier da; Lopes, Ricardo Tadeu; Magalhaes, Sarah Braga, E-mail: ademir@nuclear.ufrj.b, E-mail: ricardo@lin.ufrj.b, E-mail: smagalhaes@nuclear.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear

2010-07-01

Digital mammography has been introduced in several countries in the last years. The new technology requires new optimising methods considering for instance the increased possibility of changing the absorbed dose, mainly in modern mammographic systems that allow the operator to choose the beam quality by varying the tube voltage, and filter and target materials. In this work, the Monte Carlo code MCNPX is used in order to investigate how the average glandular dose vary with tube voltage (23-32 kV) and anode-filter combination (Mo-Mo,Mo-Rh and Rh-Rh) in digital mammographic examinations. Furthermore, the risk of breast cancer incidence attributable to mammography exams was estimated using the Biological Effects of Ionizing Radiations (BEIR) VII Committee Report. The results show that the risk of breast cancer incidence in women younger than 30 years of age tends to decrease significantly using Rh-Rh anode-filter combination and higher tube voltage. For women older than 50 years of age the variation of tube voltage, and anode-filter combination did not influence the risk values considerably. (author)

Dose and risk evaluation in digital mammography using computer modeling

International Nuclear Information System (INIS)

Correa, Samanda Cristine Arruda; Souza, Edmilson Monteiro de; Silva, Humberto de Oliveira; Silva, Ademir Xavier da; Lopes, Ricardo Tadeu; Magalhaes, Sarah Braga

2010-01-01

Digital mammography has been introduced in several countries in the last years. The new technology requires new optimising methods considering for instance the increased possibility of changing the absorbed dose, mainly in modern mammographic systems that allow the operator to choose the beam quality by varying the tube voltage, and filter and target materials. In this work, the Monte Carlo code MCNPX is used in order to investigate how the average glandular dose vary with tube voltage (23-32 kV) and anode-filter combination (Mo-Mo,Mo-Rh and Rh-Rh) in digital mammographic examinations. Furthermore, the risk of breast cancer incidence attributable to mammography exams was estimated using the Biological Effects of Ionizing Radiations (BEIR) VII Committee Report. The results show that the risk of breast cancer incidence in women younger than 30 years of age tends to decrease significantly using Rh-Rh anode-filter combination and higher tube voltage. For women older than 50 years of age the variation of tube voltage, and anode-filter combination did not influence the risk values considerably. (author)

Computer-aided detection of masses in full-field digital mammography using screen-film mammograms for training

International Nuclear Information System (INIS)

Kallenberg, Michiel; Karssemeijer, Nico

2008-01-01

It would be of great value when available databases of screen-film mammography (SFM) images can be used to train full-field digital mammography (FFDM) computer-aided detection (CAD) systems, as compilation of new databases is costly. In this paper, we investigate this possibility. Firstly, we develop a method that converts an FFDM image into an SFM-like representation. In this conversion method, we establish a relation between exposure and optical density by simulation of an automatic exposure control unit. Secondly, we investigate the effects of using the SFM images as training samples compared to training with FFDM images. Our FFDM database consisted of 266 cases, of which 102 were biopsy-proven malignant masses and 164 normals. The images were acquired with systems of two different manufacturers. We found that, when we trained our FFDM CAD system with a small number of images, training with FFDM images, using a five-fold crossvalidation procedure, outperformed training with SFM images. However, when the full SFM database, consisting of 348 abnormal cases (including 204 priors) and 810 normal cases, was used for training, SFM training outperformed FFDMA training. These results show that an existing CAD system for detection of masses in SFM can be used for FFDM images without retraining.

47 CFR 69.125 - Dedicated signalling transport.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Dedicated signalling transport. 69.125 Section... (CONTINUED) ACCESS CHARGES Computation of Charges § 69.125 Dedicated signalling transport. (a) Dedicated signalling transport shall consist of two elements, a signalling link charge and a signalling transfer point...

Radiographers supporting radiologists in the interpretation of screening mammography: a viable strategy to meet the shortage in the number of radiologists

International Nuclear Information System (INIS)

Torres-Mejía, Gabriela; Smith, Robert A.; Carranza-Flores, María de la Luz; Bogart, Andy; Martínez-Matsushita, Louis; Miglioretti, Diana L.; Kerlikowske, Karla; Ortega-Olvera, Carolina; Montemayor-Varela, Ernesto; Angeles-Llerenas, Angélica; Bautista-Arredondo, Sergio; Sánchez-González, Gilberto; Martínez-Montañez, Olga G.; Uscanga-Sánchez, Santos R.; Lazcano-Ponce, Eduardo; Hernández-Ávila, Mauricio

2015-01-01

An alternative approach to the traditional model of radiologists interpreting screening mammography is necessary due to the shortage of radiologists to interpret screening mammograms in many countries. We evaluated the performance of 15 Mexican radiographers, also known as radiologic technologists, in the interpretation of screening mammography after a 6 months training period in a screening setting. Fifteen radiographers received 6 months standardized training with radiologists in the interpretation of screening mammography using the Breast Imaging Reporting and Data System (BI-RADS) system. A challenging test set of 110 cases developed by the Breast Cancer Surveillance Consortium was used to evaluate their performance. We estimated sensitivity, specificity, false positive rates, likelihood ratio of a positive test (LR+) and the area under the subject-specific Receiver Operating Characteristic (ROC) curve (AUC) for diagnostic accuracy. A mathematical model simulating the consequences in costs and performance of two hypothetical scenarios compared to the status quo in which a radiologist reads all screening mammograms was also performed. Radiographer’s sensitivity was comparable to the sensitivity scores achieved by U.S. radiologists who took the test but their false-positive rate was higher. Median sensitivity was 73.3 % (Interquartile range, IQR: 46.7–86.7 %) and the median false positive rate was 49.5 % (IQR: 34.7–57.9 %). The median LR+ was 1.4 (IQR: 1.3-1.7 %) and the median AUC was 0.6 (IQR: 0.6–0.7). A scenario in which a radiographer reads all mammograms first, and a radiologist reads only those that were difficult for the radiographer, was more cost-effective than a scenario in which either the radiographer or radiologist reads all mammograms. Given the comparable sensitivity achieved by Mexican radiographers and U.S. radiologists on a test set, screening mammography interpretation by radiographers appears to be a possible adjunct to radiologists

Performances of different digital mammography imaging systems: Evaluation and comparison

Energy Technology Data Exchange (ETDEWEB)

Bisogni, M.G. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy)]. E-mail: giuseppina.bisogni@pi.infn.it; Bulajic, D. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); International Centre for Theoretical Physics, Trieste (Italy); Delogu, P. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Fantacci, M.E. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Novelli, M. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Quattrocchi, M. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Rosso, V. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Stefanini, A. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy)

2005-07-01

Digital mammography is entering routine clinical use and many commercial systems are now in use in the radiological units for screening and diagnostic mammography. At the same time, the research in the digital mammography field is very active in the development of more and more performing devices. In this paper we present the performance of single photon counting pixel detectors (MedipixI) tailored for digital mammographic applications. These devices are based on semiconductor (Si and GaAs) pixel detectors of different thickness, read-out by custom designed integrated circuits. To assess the imaging capability of such systems, the images of a mammographic phantom have been acquired in standard conditions for a clinical examination. The signal-to-noise ratio (SNR) of details simulating tumor masses has been evaluated. The same phantom has been also radiographed by three different commercial digital mammographic systems in the same reference conditions and a comparison in terms of SNR has been carried out. The spatial resolution of the single photon counting systems has also been evaluated by measuring the line spread function with the edge technique and then calculating the Modulation Transfer Function (MTF). The MTFs of the single photon counting systems have been compared with the MTFs of the commercial systems.

Performances of different digital mammography imaging systems: Evaluation and comparison

International Nuclear Information System (INIS)

Bisogni, M.G.; Bulajic, D.; Delogu, P.; Fantacci, M.E.; Novelli, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.

2005-01-01

Digital mammography is entering routine clinical use and many commercial systems are now in use in the radiological units for screening and diagnostic mammography. At the same time, the research in the digital mammography field is very active in the development of more and more performing devices. In this paper we present the performance of single photon counting pixel detectors (MedipixI) tailored for digital mammographic applications. These devices are based on semiconductor (Si and GaAs) pixel detectors of different thickness, read-out by custom designed integrated circuits. To assess the imaging capability of such systems, the images of a mammographic phantom have been acquired in standard conditions for a clinical examination. The signal-to-noise ratio (SNR) of details simulating tumor masses has been evaluated. The same phantom has been also radiographed by three different commercial digital mammographic systems in the same reference conditions and a comparison in terms of SNR has been carried out. The spatial resolution of the single photon counting systems has also been evaluated by measuring the line spread function with the edge technique and then calculating the Modulation Transfer Function (MTF). The MTFs of the single photon counting systems have been compared with the MTFs of the commercial systems

On Computational Power of Quantum Read-Once Branching Programs

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Farid Ablayev

2011-03-01

Full Text Available In this paper we review our current results concerning the computational power of quantum read-once branching programs. First of all, based on the circuit presentation of quantum branching programs and our variant of quantum fingerprinting technique, we show that any Boolean function with linear polynomial presentation can be computed by a quantum read-once branching program using a relatively small (usually logarithmic in the size of input number of qubits. Then we show that the described class of Boolean functions is closed under the polynomial projections.

A comparison of the accuracy of film-screen mammography, full-field digital mammography, and digital breast tomosynthesis

International Nuclear Information System (INIS)

Michell, M.J.; Iqbal, A.; Wasan, R.K.; Evans, D.R.; Peacock, C.; Lawinski, C.P.; Douiri, A.; Wilson, R.; Whelehan, P.

2012-01-01

Aim: To measure the change in diagnostic accuracy of conventional film-screen mammography and full-field digital mammography (FFDM) with the addition of digital breast tomosynthesis (DBT) in women recalled for assessment following routine screening. Materials and methods: Ethics approval for the study was granted. Women recalled for assessment following routine screening with screen-film mammography were invited to participate. Participants underwent bilateral, two-view FFDM and two-view DBT. Readers scored each lesion separately for probability of malignancy on screen-film mammography, FFDM, and then DBT. The scores were compared with the presence or absence of malignancy based on the final histopathology outcome. Results: Seven hundred and thirty-eight women participated (93.2% recruitment rate). Following assessment 204 (26.8%) were diagnosed as malignant (147 invasive and 57 in-situ tumours), 286 (37.68%) as benign, and 269 (35.4%) as normal. The diagnostic accuracy was evaluated by using receiving operating characteristic (ROC) and measurement of area under the curve (AUC). The AUC values demonstrated a significant (p = 0.0001) improvement in the diagnostic accuracy with the addition of DBT combined with FFDM and film-screen mammography (AUC = 0.9671) when compared to FFDM plus film-screen mammography (AUC = 0.8949) and film-screen mammography alone (AUC = 0.7882). The effect was significantly greater for soft-tissue lesions [AUC was 0.9905 with the addition of DBT and AUC was 0.9201 for FFDM with film-screen mammography combined (p = 0.0001)] compared to microcalcification [with the addition of DBT (AUC = 0.7920) and for FFDM with film-screen mammography combined (AUC = 0.7843; p = 0.3182)]. Conclusion: The addition of DBT increases the accuracy of mammography compared to FFDM and film-screen mammography combined and film-screen mammography alone in the assessment of screen-detected soft-tissue mammographic abnormalities.

Operating Dedicated Data Centers - Is It Cost-Effective?

Science.gov (United States)

Ernst, M.; Hogue, R.; Hollowell, C.; Strecker-Kellog, W.; Wong, A.; Zaytsev, A.

2014-06-01

The advent of cloud computing centres such as Amazon's EC2 and Google's Computing Engine has elicited comparisons with dedicated computing clusters. Discussions on appropriate usage of cloud resources (both academic and commercial) and costs have ensued. This presentation discusses a detailed analysis of the costs of operating and maintaining the RACF (RHIC and ATLAS Computing Facility) compute cluster at Brookhaven National Lab and compares them with the cost of cloud computing resources under various usage scenarios. An extrapolation of likely future cost effectiveness of dedicated computing resources is also presented.

Comparison of image quality between mammography dedicated monitor and UHD 4K monitor, using standard mammographic phantom: A preliminary study

Energy Technology Data Exchange (ETDEWEB)

Lee, Ji Young; Cha, Soon Joo; Hong, Sung Hwan; Kim, Su Young; Kim, Yong Hoon; Kim, You Sung; Kim, Jeong A [Dept. of Radiology, Inje Unveristy Ilsan Paik Hospital, Goyang (Korea, Republic of)

2017-03-15

Using standard mammographic phantom images, we compared the image quality obtained between a mammography dedicated 5 megapixel monitor (5M) and a UHD 4K (4K) monitor with digital imaging and communications in medicine display, to investigate the possibility of clinical application of 4K monitors. Three different exposures (autoexposure, overexposure and underexposure) images of mammographic phantom were obtained, and six radiologists independently evaluated the images in 5M and 4K without image modulation, by scoring of fibers, groups of specks and masses within the phantom image. The mean score of each object on both monitors was independently analyzed, using t-test and interobserver reliability by intraclass correlation coefficient (ICC) of SPSS. The overall mean scores of fiber, group of specks, and mass in 5M were 4.25, 3.92, and 3.28 respectively, and scores obtained in 4K monitor were 3.81, 3.58, and 3.14, respectively. No statistical difference was seen in scores of fiber and mass between the two monitors at all exposure conditions, but the score of group of specks in 4K was statistically lower in the overall (p = 0.0492) and in underexposure conditions (p = 0.012). The ICC for interobserver reliability was excellent (0.874). Our study suggests that since the mammographic phantom images are appropriate with no significant difference in image quality observed between the two monitors, the 4K monitor could be used for clinical studies. Since this is a small preliminary study using phantom images, the result may differ in actual mammographic images, and subsequent investigation with clinical mammographic images is required.

Efficacy of computer-aided detection system for screening mammography

International Nuclear Information System (INIS)

Saito, Mioko; Ohnuki, Koji; Yamada, Takayuki; Saito, Haruo; Ishibashi, Tadashi; Ohuchi, Noriaki; Takahashi, Shoki

2002-01-01

A study was conducted to evaluate the efficacy of a computer-aided detection (CAD) system for screening mammography (MMG). Screening mammograms of 2,231 women aged over 50 yr were examined. Medio-lateral oblique (MLO) images were obtained, and two expert observers interpreted the mammograms by consensus. First, each mammogram was interpreted without the assistance of CAD, followed immediately by a re-evaluation of areas marked by the CAD system. Data were recorded to measure the effect of CAD on the recall rate, cancer detection rate and detection rate of masses, microcalcifications and other findings. The CAD system increased the recall rate from 2.3% to 2.6%. Six recalled cases were diagnosed as breast cancer pathologically, and CAD detected all of these lesions. Seven additional cases in which CAD detected abnormal findings had no malignancy. The detection rate of CAD for microcalcifications was high (95.0%). However, the detection rate for mass lesions and other findings was low (29.2% and 25.0% respectively). The false positivity rate was 0.13/film for microcalcifications, and 0.25/film for mass lesions. The efficacy of the CAD system for detecting microcalcifications on screening mammograms was confirmed. However, the low detection rate of mass lesions and relatively high rate of false positivity need to be further improved. (author)

Contrast-enhanced spectral mammography vs. mammography and MRI - clinical performance in a multi-reader evaluation

Energy Technology Data Exchange (ETDEWEB)

Fallenberg, Eva M.; Schmitzberger, Florian F.; Amer, Heba; Engelken, Florian; Bick, Ulrich; Hamm, Bernd [Charite Universitaetsmedizin Berlin, Clinic of Radiology, Campus Virchow-Klinikum, Berlin (Germany); Ingold-Heppner, Barbara [Charite - Universitaetsmedizin Berlin, Institut of Pathology, Berlin (Germany); Balleyguier, Corinne; Dromain, Clarisse [Gustave Roussy Cancer Campus, Department of Radiology, Villejuif (France); Diekmann, Felix [St. Joseph-Stift Bremen, Department of Medical Imaging, Bremen (Germany); Mann, Ritse M. [Radboud University Nijmegen Medical Centre, Department of Radiology, Nijmegen (Netherlands); Renz, Diane M. [Universitaetsklinikum Jena, Department of Radiology, Jena (Germany)

2017-07-15

To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) to digital mammography (MG) and magnetic resonance imaging (MRI) in a prospective two-centre, multi-reader study. One hundred seventy-eight women (mean age 53 years) with invasive breast cancer and/or DCIS were included after ethics board approval. MG, CESM and CESM + MG were evaluated by three blinded radiologists based on amended ACR BI-RADS criteria. MRI was assessed by another group of three readers. Receiver-operating characteristic (ROC) curves were compared. Size measurements for the 70 lesions detected by all readers in each modality were correlated with pathology. Reading results for 604 lesions were available (273 malignant, 4 high-risk, 327 benign). The area under the ROC curve was significantly larger for CESM alone (0.84) and CESM + MG (0.83) compared to MG (0.76) (largest advantage in dense breasts) while it was not significantly different from MRI (0.85). Pearson correlation coefficients for size comparison were 0.61 for MG, 0.69 for CESM, 0.70 for CESM + MG and 0.79 for MRI. This study showed that CESM, alone and in combination with MG, is as accurate as MRI but is superior to MG for lesion detection. Patients with dense breasts benefitted most from CESM with the smallest additional dose compared to MG. (orig.)

The self-referred mammography patient

International Nuclear Information System (INIS)

Reynolds, H.E.; Jackson, V.P.

1990-01-01

This paper compares the demographics, knowledge, and attitudes of women who refer themselves for screening mammography with those who undergo mammography on the advice of their physicians. Four hundred eighty-five consecutive mammography patients (437 doctor preferred [DR], 48 self-referred [SR]) completed a survey during their mammography appointment. The sample population contained a wide range of socioeconomic groups. While similar in age, race, and employment status to DR patients, SR patients were significantly more likely to have a family income of more than 30,000 per year, be college graduates, and report that they were in good or excellent health

Present state of computer-aided diagnosis (CAD) development

International Nuclear Information System (INIS)

Fujita, Hiroshi

2007-01-01

Topics of computer-aided detection (CAD) are reviewed. Commercially available, Food and Drug Administration (FDA)-approved CAD systems are for fields of breast cancer (mammography), chest (flat X-ray and CT imaging) and colon (polyp detection). In Japan, only mammography CAD is approved. Efficacy of CAD is controversial, for which reliable database is important, and its construction is under development in various medical fields. Digitalized image is now popularized, which conceivably leads to improve the cost-effectiveness of diagnosis with CAD. For incentive, approval for health insurance would be the case as seen in the increased CAD sale by R2 Technology Co., and MHLW actually assists facilities to introduce the reading-aid system of mammography by sharing a half of its cost. There are 2 big projects for CAD study supported by MECSST, which the author concerns. One is the development of diagnostic aid for the multi-dimensional medical images where the multi-organ, multi-disease CAD system is considered. The other involves the CAD in brain MRI, in breast US and in eyeground picture. It is not in so far future for patients and doctors to fully enjoy the benefit of CAD. (R.T.)

Eye movement analysis of reading from computer displays, eReaders and printed books.

Science.gov (United States)

Zambarbieri, Daniela; Carniglia, Elena

2012-09-01

To compare eye movements during silent reading of three eBooks and a printed book. The three different eReading tools were a desktop PC, iPad tablet and Kindle eReader. Video-oculographic technology was used for recording eye movements. In the case of reading from the computer display the recordings were made by a video camera placed below the computer screen, whereas for reading from the iPad tablet, eReader and printed book the recording system was worn by the subject and had two cameras: one for recording the movement of the eyes and the other for recording the scene in front of the subject. Data analysis provided quantitative information in terms of number of fixations, their duration, and the direction of the movement, the latter to distinguish between fixations and regressions. Mean fixation duration was different only in reading from the computer display, and was similar for the Tablet, eReader and printed book. The percentage of regressions with respect to the total amount of fixations was comparable for eReading tools and the printed book. The analysis of eye movements during reading an eBook from different eReading tools suggests that subjects' reading behaviour is similar to reading from a printed book. © 2012 The College of Optometrists.

Patient dosimetry in computed tomography and mammography: the case of CENHOSOA (Centre Hospitalier Soavinandriana) and Polyclinic Ilafy

International Nuclear Information System (INIS)

RABEARISOA, H.

2011-01-01

Medical exposures are among the largest artificial source of exposure to ionizing radiation of the population. It is necessary that the protection measures should be taken to prevent over or under exposure of patients. The aim of this work is to assess the delivered dose to patient in computed tomography and in mammography. The study was performed at the Service of Radiology and Medical Imaging of the Centre Hospitalier de Soavinandriana and the Polyclinic d'Ilafy. This work is a part of The International Atomic Energy Agency (IAEA) project (RAF/9/033) untitled S trengthening Radiological Protection Of Patient and Control of Medical Exposure . Results showed that the measured doses are lower than the reference standard established by the IAEA and the Commission of the European Communities, except for the examination realized at 40 kV and 50 kV in mammography. We performed also comparison of the dose measured by the ionizing chamber and the Thermoluminescent Dosimeter (TLD). Deviation between these two measurements is less than 5%. This is due to the uncertainty during the calibration procedures of the TLD. In conclusion, results of this work are useful for the implementation of the regulation in radiation protection in Madagascar. [fr

Evaluation of radiographers’ mammography screen-reading accuracy in Australia

International Nuclear Information System (INIS)

Debono, Josephine C; Poulos, Ann E; Houssami, Nehmat; Turner, Robin M; Boyages, John

2015-01-01

This study aimed to evaluate the accuracy of radiographers’ screen-reading mammograms. Currently, radiologist workforce shortages may be compromising the BreastScreen Australia screening program goal to detect early breast cancer. The solution to a similar problem in the United Kingdom has successfully encouraged radiographers to take on the role as one of two screen-readers. Prior to consideration of this strategy in Australia, educational and experiential differences between radiographers in the United Kingdom and Australia emphasise the need for an investigation of Australian radiographers’ screen-reading accuracy. Ten radiographers employed by the Westmead Breast Cancer Institute with a range of radiographic (median = 28 years), mammographic (median = 13 years) and BreastScreen (median = 8 years) experience were recruited to blindly and independently screen-read an image test set of 500 mammograms, without formal training. The radiographers indicated the presence of an abnormality using BI-RADS®. Accuracy was determined by comparison with the gold standard of known outcomes of pathology results, interval matching and client 6-year follow-up. Individual sensitivity and specificity levels ranged between 76.0% and 92.0%, and 74.8% and 96.2% respectively. Pooled screen-reader accuracy across the radiographers estimated sensitivity as 82.2% and specificity as 89.5%. Areas under the reading operating characteristic curve ranged between 0.842 and 0.923. This sample of radiographers in an Australian setting have adequate accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training, accuracy levels will improve, and with support, radiographers have the potential to be one of the two screen-readers in the BreastScreen Australia program, contributing to timeliness and improved program outcomes

Evaluation of radiographers’ mammography screen-reading accuracy in Australia

Energy Technology Data Exchange (ETDEWEB)

Debono, Josephine C, E-mail: josephine.debono@bci.org.au [Westmead Breast Cancer Institute, Westmead, New South Wales (Australia); Poulos, Ann E [Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, Lidcombe, New South Wales (Australia); Houssami, Nehmat [Screening and Test Evaluation Program, School of Public Health (A27), Sydney Medical School, University of Sydney, Sydney, New South Wales (Australia); Turner, Robin M [School of Public Health and Community Medicine, University of New South Wales, Sydney, New South Wales (Australia); Boyages, John [Macquarie University Cancer Institute, Macquarie University Hospital, Australian School of Advanced Medicine, Macquarie University, Sydney, New South Wales (Australia); Westmead Breast Cancer Institute, Westmead, New South Wales (Australia)

2015-03-15

This study aimed to evaluate the accuracy of radiographers’ screen-reading mammograms. Currently, radiologist workforce shortages may be compromising the BreastScreen Australia screening program goal to detect early breast cancer. The solution to a similar problem in the United Kingdom has successfully encouraged radiographers to take on the role as one of two screen-readers. Prior to consideration of this strategy in Australia, educational and experiential differences between radiographers in the United Kingdom and Australia emphasise the need for an investigation of Australian radiographers’ screen-reading accuracy. Ten radiographers employed by the Westmead Breast Cancer Institute with a range of radiographic (median = 28 years), mammographic (median = 13 years) and BreastScreen (median = 8 years) experience were recruited to blindly and independently screen-read an image test set of 500 mammograms, without formal training. The radiographers indicated the presence of an abnormality using BI-RADS®. Accuracy was determined by comparison with the gold standard of known outcomes of pathology results, interval matching and client 6-year follow-up. Individual sensitivity and specificity levels ranged between 76.0% and 92.0%, and 74.8% and 96.2% respectively. Pooled screen-reader accuracy across the radiographers estimated sensitivity as 82.2% and specificity as 89.5%. Areas under the reading operating characteristic curve ranged between 0.842 and 0.923. This sample of radiographers in an Australian setting have adequate accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training, accuracy levels will improve, and with support, radiographers have the potential to be one of the two screen-readers in the BreastScreen Australia program, contributing to timeliness and improved program outcomes.

Quality control: comparison of images quality with screen film system and digital mammography CR

International Nuclear Information System (INIS)

Alvarenga, Frederico L.; Nogueira, Maria do Socorro

2008-01-01

The mammography screen film system should be used as part of processing chemicals, revelation process, equipment and this system has have a progressive replacing by the digital technology Full Field Digital Mammography FFDM, Computed Radiography (CR) Mammography and hardcopy. This new acquisition process of medical images has improved radiology section; however it is necessary efficient means for evaluating of the quality parameters. It should be considered taking into account the adaptation of the existent equipment and that procedures adopted for the exam, as well the adaptation of the new mammography films, the radiologist view box constitutes a part of the quality control program. This program aims at obtaining radiography with good quality that allows obtaining more information for the diagnosis and decreases the patient dose. For evaluation the quality image, this article is focused on presenting the differences regarding the acquired images through simulator mammography radiographic PMMA (Poly methyl methacrylate) in CR Mammography system and screen film system. The tests were accomplished at the same equipment of Mammography with the Automatic Exposure Control using a tension of 28 kV for both systems. The quality tests evaluated the spatial resolution, the own structures of the phantom, artifacts, optical density and contrast with conventional and laser films by mammography system. The installation for the accomplishment of the test has a quality control program. The evaluation was based on the pattern developed by the competent organ of the State of Minas Gerais. In this study, it was verified that the suitable Phantom Mama used by the Brazilian School of Radiology for conventional mammography did not obtain satisfactory result for Spatial Resolution in the digital mammography system CR. The final aim of this work is to obtain parameters to characterize the reference phantom quality image in an objective way. These parameters will be used to compare

Improved scintimammography using a high-resolution camera mounted on an upright mammography gantry

Energy Technology Data Exchange (ETDEWEB)

Itti, Emmanuel; Patt, Bradley E.; Diggles, Linda E.; MacDonald, Lawrence; Iwanczyk, Jan S.; Mishkin, Fred S.; Khalkhali, Iraj E-mail: nephrad@aol.com

2003-01-21

{sup 99m}Tc-sestamibi scintimammography (SMM) is a useful adjunct to conventional X-ray mammography (XMM) for the assessment of breast cancer. An increasing number of studies has emphasized fair sensitivity values for the detection of tumors >1 cm, compared to XMM, particularly in situations where high glandular breast densities make mammographic interpretation difficult. In addition, SMM has demonstrated high specificity for cancer, compared to various functional and anatomic imaging modalities. However, large field-of-view (FOV) gamma cameras are difficult to position close to the breasts, which decreases spatial resolution and subsequently, the sensitivity of detection for tumors <1 cm. New dedicated detectors featuring small FOV and increased spatial resolution have recently been developed. In this setting, improvement in tumor detection sensitivity, particularly with regard to small cancers is expected. At Division of Nuclear Medicine, Harbor-UCLA Medical Center, we have performed over 2000 SMM within the last 9 years. We have recently used a dedicated breast camera (LumaGEM) featuring a 12.8x12.8 cm{sup 2} FOV and an array of 2x2x6 mm{sup 3} discrete crystals coupled to a photon-sensitive photomultiplier tube readout. This camera is mounted on a mammography gantry allowing upright imaging, medial positioning and use of breast compression. Preliminary data indicates significant enhancement of spatial resolution by comparison with standard imaging in the first 10 patients. Larger series will be needed to conclude on sensitivity/specificity issues.

Clear-PEM: A PET imaging system dedicated to breast cancer diagnostics

CERN Document Server

Abreu, M C; Albuquerque, E; Almeida, F G; Almeida, P; Amaral, P; Auffray, Etiennette; Bento, P; Bruyndonckx, P; Bugalho, R; Carriço, B; Cordeiro, H; Ferreira, M; Ferreira, N C; Gonçalves, F; Lecoq, Paul; Leong, C; Lopes, F; Lousã, P; Luyten, J; Martins, M V; Matela, N; Rato-Mendes, P; Moura, R; Nobre, J; Oliveira, N; Ortigão, C; Peralta, L; Rego, J; Ribeiro, R; Rodrigues, P; Santos, A I; Silva, J C; Silva, M M; Tavernier, Stefaan; Teixeira, I C; Texeira, J P; Trindade, A; Trummer, Julia; Varela, J

2007-01-01

The Clear-PEM scanner for positron emission mammography under development is described. The detector is based on pixelized LYSO crystals optically coupled to avalanche photodiodes and readout by a fast low-noise electronic system. A dedicated digital trigger (TGR) and data acquisition (DAQ) system is used for on-line selection of coincidence events with high efficiency, large bandwidth and small dead-time. A specialized gantry allows to perform exams of the breast and of the axilla. In this paper we present results of the measurement of detector modules that integrate the system under construction as well as the imaging performance estimated from Monte Carlo simulated data.

Dose and diagnostic performance comparison between phase-contrast mammography with synchrotron radiation and digital mammography: a clinical study report.

Science.gov (United States)

Fedon, Christian; Rigon, Luigi; Arfelli, Fulvia; Dreossi, Diego; Quai, Elisa; Tonutti, Maura; Tromba, Giuliana; Cova, Maria Assunta; Longo, Renata

2018-01-01

Two dosimetric quantities [mean glandular dose (MGD) and entrance surface air kerma (ESAK)] and the diagnostic performance of phase-contrast mammography with synchrotron radiation (MSR) are compared to conventional digital mammography (DM). Seventy-one patients (age range, 41 to 82 years) underwent MSR after a DM examination if questionable or suspicious breast abnormalities were not clarified by ultrasonography. The MGD and the ESAK delivered in both examinations were evaluated and compared. Two on-site radiologists rated the images in consensus according to the Breast Imaging Reporting and Data System assessment categories, which were then correlated with the final diagnoses by means of statistical generalized linear models (GLMs). Receiver operating characteristic curves were also used to assess the diagnostic performance by comparing the area under the curve (AUC). An important MGD and ESAK reduction was observed in MSR due to the monoenergetic beam. In particular, an average 43% reduction was observed for the MGD and a reduction of more than 50% for the ESAK. GLM showed higher diagnostic accuracy, especially in terms of specificity, for MSR, confirmed by AUC analysis ([Formula: see text]). The study design implied that the population was characterized by a high prevalence of disease and that the radiologists, who read the DM images before referring the patient to MSR, could have been influenced in their assessments. Within these limitations, the use of synchrotron radiation with the phase-contrast technique applied to mammography showed an important dose reduction and a higher diagnostic accuracy compared with DM. These results could further encourage research on the translation of x-ray phase-contrast imaging into the clinics.

Developing a Mass Media Campaign to Promote Mammography Awareness in African American Women in the Nation's Capital.

Science.gov (United States)

Wallington, Sherrie Flynt; Oppong, Bridget; Iddirisu, Marquita; Adams-Campbell, Lucile L

2017-12-26

This study developed and examined the reach and impact of a culturally appropriate mass media campaign pilot, designed to increase awareness about the importance of mammography screening and the available community mammography services for low-income African American women ages 40 and above. We conducted formative research using focus groups to inform campaign development, resulting in five emergent themes-good breast health, holistic views of healthiness, cancer fatalism, fear of mammogram machines, and mammogram affordability. The campaign targeted specific low-income African American communities in the District of Columbia via print ads in Metro stations and on buses, print ads in the Washington Informer, and online ads on a local TV network website. Data were collected before, during, and after campaign implementation to assess reach and impact. Reach was measured by number of impressions (number of people exposed to the campaign), while impact was assessed via online ad click-through rates, website use and referrals, and mammography center calls. The campaign was successful in reaching the target audience, with a total combined reach from all media of 9,479,386 impressions. In addition, the mammography center received significant increases in new website visitors (1482 during the campaign, compared to 24 during the preceding period) as well as 97 calls to the dedicated phone line. Further research involving a more long-term investment in terms of funding and campaign run time, coupled with a more robust evaluation, is needed to assess if culturally appropriate mass media campaigns can generate increased mammography screening rates and decrease breast-cancer-related mortality.

The mammography screening employee inreach program.

Science.gov (United States)

Robinson, Joanne; Seltzer, Vicki; Lawrence, Loretta; Autz, George; Kostroff, Karen; Weiselberg, Lora; Colagiacomo, Maria

2007-02-01

To determine whether our health care employees were undergoing mammography screening according to American Cancer Society guidelines and to determine whether aggressive outreach, education and streamlining of mammography scheduling could improve compliance. All female employees at North Shore University Hospital (NSUH) and several other health system facilities (SF) were sent mailings to their homes that included breast health education and mammography screening guidelines, a questionnaire regarding their own mammography screening history and the opportunity to have their mammography screening scheduled by the Mammography Screening Employee Inreach Program (MSEIP) coordinator. Of the approximately 2,700 female employees aged 40 and over at NSUH and SF, 2,235 (82.7%) responded to the questionnaire, and 1,455 had a mammogram done via the MSEIP. Of the 1,455, 43% either were overdue for a mammogram or had never had one. During a second year of the MSEIP at NSUH and SF, an additional 1,706 mammograms were done. People employed in health care jobs do not necessarily avail themselves of appropriate health care screening. An aggressive program that utilized education, outreach and assistance with scheduling was effective in increasing compliance with mammography screening.

Operating dedicated data centers – is it cost-effective?

International Nuclear Information System (INIS)

Ernst, M; Hogue, R; Hollowell, C; Strecker-Kellog, W; Wong, A; Zaytsev, A

2014-01-01

The advent of cloud computing centres such as Amazon's EC2 and Google's Computing Engine has elicited comparisons with dedicated computing clusters. Discussions on appropriate usage of cloud resources (both academic and commercial) and costs have ensued. This presentation discusses a detailed analysis of the costs of operating and maintaining the RACF (RHIC and ATLAS Computing Facility) compute cluster at Brookhaven National Lab and compares them with the cost of cloud computing resources under various usage scenarios. An extrapolation of likely future cost effectiveness of dedicated computing resources is also presented.

Valorization procedure of x-ray equipment in the mammography equipment

International Nuclear Information System (INIS)

Ruiz, M. A.; Ordonez, J.; Antolin, E.; Andres, J. C. de; Gonzalez, I.; Arranz, L.; Sastre, J. M.; Ferrer, N.

2006-01-01

The Ramon y Cajal Hospital mammography service has three X-rays units, two of them with high resolution computed radiography (CR) system and one with flat-panel (FP)-based full-field digital mammography system. Periodic control dose tests in patients have shown lower glandular dose levels (DGM) than references provided by European Protocol for de Quality Control of de Physical and Technical Aspects of Mammography Screening. In this work, we have tried to establish an easy method for DGM calculation which is representative of the three equipment results. For this aim, we have defined an index which is measured along the time like a reference point. This index is defined as the relation between the blind test punctuations of a standard phantom image given by at least three radiologists in the Unit, and the average DGM values obtained in 20 patients in each Unit (using random thickness and random mama composition). (Author)

Scalable cloud without dedicated storage

Science.gov (United States)

Batkovich, D. V.; Kompaniets, M. V.; Zarochentsev, A. K.

2015-05-01

We present a prototype of a scalable computing cloud. It is intended to be deployed on the basis of a cluster without the separate dedicated storage. The dedicated storage is replaced by the distributed software storage. In addition, all cluster nodes are used both as computing nodes and as storage nodes. This solution increases utilization of the cluster resources as well as improves fault tolerance and performance of the distributed storage. Another advantage of this solution is high scalability with a relatively low initial and maintenance cost. The solution is built on the basis of the open source components like OpenStack, CEPH, etc.

Comparative study of dose estimation in the change a conventional mammography to digital mammography

International Nuclear Information System (INIS)

Vazquez Vazquez, R.; Otero Martinez, C.; Soto Bua, M.; Santamarina Vazquez, F.; Carril Iglesias, S.; Lobato Busto, R.; Luna Vega, V.; Mosquera Sueiro, J.; Sqanchez Garcia, M.; Pombar Camean, M.

2011-01-01

Mammographic studies are now one of the most demanding radiological because of its effectiveness in detecting breast cancer early. The introduction of digital mammography has been a major advance because it has overcome some of the limitations of conventional systems. Due to the nature of the radiosensitive glandular tissue becomes very important control of the dose given to patients. In the present study is to analyze the variations in dosimetry that can exist between a conventional mammography and digital mammography.

Radiation exposure of contrast-enhanced spectral mammography compared with full-field digital mammography.

Science.gov (United States)

Jeukens, Cécile R L P N; Lalji, Ulrich C; Meijer, Eduard; Bakija, Betina; Theunissen, Robin; Wildberger, Joachim E; Lobbes, Marc B I

2014-10-01

Contrast-enhanced spectral mammography (CESM) shows promising initial results but comes at the cost of increased dose as compared with full-field digital mammography (FFDM). We aimed to quantitatively assess the dose increase of CESM in comparison with FFDM. Radiation exposure-related data (such as kilovoltage, compressed breast thickness, glandularity, entrance skin air kerma (ESAK), and average glandular dose (AGD) were retrieved for 47 CESM and 715 FFDM patients. All examinations were performed on 1 mammography unit. Radiation dose values reported by the unit were validated by phantom measurements. Descriptive statistics of the patient data were generated using a statistical software package. Dose values reported by the mammography unit were in good qualitative agreement with those of phantom measurements. Mean ESAK was 10.5 mGy for a CESM exposure and 7.46 mGy for an FFDM exposure. Mean AGD for a CESM exposure was 2.80 mGy and 1.55 mGy for an FFDM exposure. Compared with our institutional FFDM, the AGD of a single CESM exposure is increased by 1.25 mGy (+81%), whereas ESAK is increased by 3.07 mGy (+41%). Dose values of both techniques meet the recommendations for maximum dose in mammography.

WE-FG-207A-00: Advances in Dedicated Breast CT

International Nuclear Information System (INIS)

2016-01-01

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

WE-FG-207A-00: Advances in Dedicated Breast CT

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-06-15

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

Quality assurance of mammography training courses via questionnaires. Eighth report

International Nuclear Information System (INIS)

Kotsuma, Yoshikazu; Endo, Tokiko; Iwase, Takuji

2007-01-01

To maintain a sufficient number of qualified reading doctors for breast cancer mammography screening, we have held training courses across the nation. Grade-up examinations have been carried out for doctors who had failed to attain grade A or B at the training courses. We have evaluated the quality assurance of the examinations via questionnaires and reported the results on 7 previous occasions. In the present investigation, we reviewed all answers obtained from questionnaires at the previous 19 examinations, from the first one (November, 2000) until the last one (March, 2007). There were a total of 3,380 applicants, of whom 402 (11.9%) obtained grade A and 2,008 (59.4%) grade B. Thus a total 2,410 applicants (71.3%) obtained either A or B, and this rate was considerably superior to the 56% obtained in the first three examinations, although the former rate included the results of repeated applicants. These good results may have been due to an increase in the quality of the training courses and may have been affected by conducting the examinations not only in Nagoya but also in Tokyo and Osaka. In a period of about 10 months after April, 2004, the certification standard was increased and a system of certification reappraisal every 5 years was adopted. At that time, more than 75% of all applicants were A- or B-certified doctors at the 9th and 10th examinations, and the good results might have reflected the fact that many doctors tried hard to maintain a high reading ability. In February, 2005, the certification standard reverted to the previous one for various reasons, and the rate of A- or B-certified doctors decreased. In October, 2006, the examination changed from 100 questions concerning one-direction mammography to 50 one-direction questions and 50 two-direction questions, because of the adoption of two-direction mammography to age 40 years. Since it was widely recognized that the second reading at breast cancer screening should be done by A-certified doctors

Computer Game Play as an Imaginary Stage for Reading: Implicit Spatial Effects of Computer Games Embedded in Hard Copy Books

Science.gov (United States)

Smith, Glenn Gordon

2012-01-01

This study compared books with embedded computer games (via pentop computers with microdot paper and audio feedback) with regular books with maps, in terms of fifth graders' comprehension and retention of spatial details from stories. One group read a story in hard copy with embedded computer games, the other group read it in regular book format…

Educational Technology Network: a computer conferencing system dedicated to applications of computers in radiology practice, research, and education.

Science.gov (United States)

D'Alessandro, M P; Ackerman, M J; Sparks, S M

1993-11-01

Educational Technology Network (ET Net) is a free, easy to use, on-line computer conferencing system organized and funded by the National Library of Medicine that is accessible via the SprintNet (SprintNet, Reston, VA) and Internet (Merit, Ann Arbor, MI) computer networks. It is dedicated to helping bring together, in a single continuously running electronic forum, developers and users of computer applications in the health sciences, including radiology. ET Net uses the Caucus computer conferencing software (Camber-Roth, Troy, NY) running on a microcomputer. This microcomputer is located in the National Library of Medicine's Lister Hill National Center for Biomedical Communications and is directly connected to the SprintNet and the Internet networks. The advanced computer conferencing software of ET Net allows individuals who are separated in space and time to unite electronically to participate, at any time, in interactive discussions on applications of computers in radiology. A computer conferencing system such as ET Net allows radiologists to maintain contact with colleagues on a regular basis when they are not physically together. Topics of discussion on ET Net encompass all applications of computers in radiological practice, research, and education. ET Net has been in successful operation for 3 years and has a promising future aiding radiologists in the exchange of information pertaining to applications of computers in radiology.

Individualized computer-aided education in mammography based on user modeling: concept and preliminary experiments.

Science.gov (United States)

Mazurowski, Maciej A; Baker, Jay A; Barnhart, Huiman X; Tourassi, Georgia D

2010-03-01

The authors propose the framework for an individualized adaptive computer-aided educational system in mammography that is based on user modeling. The underlying hypothesis is that user models can be developed to capture the individual error making patterns of radiologists-in-training. In this pilot study, the authors test the above hypothesis for the task of breast cancer diagnosis in mammograms. The concept of a user model was formalized as the function that relates image features to the likelihood/extent of the diagnostic error made by a radiologist-in-training and therefore to the level of difficulty that a case will pose to the radiologist-in-training (or "user"). Then, machine learning algorithms were implemented to build such user models. Specifically, the authors explored k-nearest neighbor, artificial neural networks, and multiple regression for the task of building the model using observer data collected from ten Radiology residents at Duke University Medical Center for the problem of breast mass diagnosis in mammograms. For each resident, a user-specific model was constructed that predicts the user's expected level of difficulty for each presented case based on two BI-RADS image features. In the experiments, leave-one-out data handling scheme was applied to assign each case to a low-predicted-difficulty or a high-predicted-difficulty group for each resident based on each of the three user models. To evaluate whether the user model is useful in predicting difficulty, the authors performed statistical tests using the generalized estimating equations approach to determine whether the mean actual error is the same or not between the low-predicted-difficulty group and the high-predicted-difficulty group. When the results for all observers were pulled together, the actual errors made by residents were statistically significantly higher for cases in the high-predicted-difficulty group than for cases in the low-predicted-difficulty group for all modeling

Digital mammography; Mamografia digital

Energy Technology Data Exchange (ETDEWEB)

Chevalier, M.; Torres, R.

2010-07-01

Mammography represents one of the most demanding radiographic applications, simultaneously requiring excellent contrast sensitivity, high spatial resolution, and wide dynamic range. Film/screen is the most widely extended image receptor in mammography due to both its high spatial resolution and contrast. The film/screen limitations are related with its narrow latitude, structural noise and that is at the same time the medium for the image acquisition, storage and presentation. Several digital detector made with different technologies can overcome these difficulties. Here, these technologies as well as their main advantages and disadvantages are analyzed. Also it is discussed its impact on the mammography examinations, mainly on the breast screening programs. (Author).

An observer study comparing spot imaging regions selected by radiologists and a computer for an automated stereo spot mammography technique

International Nuclear Information System (INIS)

Goodsitt, Mitchell M.; Chan, Heang-Ping; Lydick, Justin T.; Gandra, Chaitanya R.; Chen, Nelson G.; Helvie, Mark A.; Bailey, Janet E.; Roubidoux, Marilyn A.; Paramagul, Chintana; Blane, Caroline E.; Sahiner, Berkman; Petrick, Nicholas A.

2004-01-01

We are developing an automated stereo spot mammography technique for improved imaging of suspicious dense regions within digital mammograms. The technique entails the acquisition of a full-field digital mammogram, automated detection of a suspicious dense region within that mammogram by a computer aided detection (CAD) program, and acquisition of a stereo pair of images with automated collimation to the suspicious region. The latter stereo spot image is obtained within seconds of the original full-field mammogram, without releasing the compression paddle. The spot image is viewed on a stereo video display. A critical element of this technique is the automated detection of suspicious regions for spot imaging. We performed an observer study to compare the suspicious regions selected by radiologists with those selected by a CAD program developed at the University of Michigan. True regions of interest (TROIs) were separately determined by one of the radiologists who reviewed the original mammograms, biopsy images, and histology results. We compared the radiologist and computer-selected regions of interest (ROIs) to the TROIs. Both the radiologists and the computer were allowed to select up to 3 regions in each of 200 images (mixture of 100 CC and 100 MLO views). We computed overlap indices (the overlap index is defined as the ratio of the area of intersection to the area of interest) to quantify the agreement between the selected regions in each image. The averages of the largest overlap indices per image for the 5 radiologist-to-computer comparisons were directly related to the average number of regions per image traced by the radiologists (about 50% for 1 region/image, 84% for 2 regions/image and 96% for 3 regions/image). The average of the overlap indices with all of the TROIs was 73% for CAD and 76.8%+/-10.0% for the radiologists. This study indicates that the CAD determined ROIs could potentially be useful for a screening technique that includes stereo spot

[Advances in research on automatic exposure control of mammography system].

Science.gov (United States)

Wang, Guoyi; Ye, Chengfu; Wu, Haiming; Wang, Tainfu; Zhang, Hong

2014-12-01

Mammography imaging is one of the most demanding imaging modalities from the point of view of the bal- ance between image quality (the visibility of small size and/or low contrast structures) and dose (screening of many asymptomatic people). Therefore, since the introduction of the first dedicated mammographic units, many efforts have been directed to seek the best possible image quality while minimizing patient dose. The performance of auto- matic exposure control (AEC) is the manifestation of this demand. The theory of AEC includes exposure detection and optimization and also involves some accomplished methodology. This review presents the development and present situa- tion of spectrum optimization, detector evolution, and the way how to accomplish and evaluate AEC methods.

Comparison of average glandular dose in screen-film and digital mammography using breast tissue-equivalent phantom

International Nuclear Information System (INIS)

Shin, Gwi Soon; Kim, Jung Min; Kim, You Hyun; Choi, Jong Hak; Kim, Chang Kyun

2007-01-01

In recent years, mammography system is changed rapidly from conventional screen-film system to digital system for application to screening and diagnosis. Digital mammography system provides several advantages over screen-film mammography system. According to the information provided by the manufacturer, digital mammography system offers radiation dose reduction in comparison with screen-film mammography system, because of digital detector, particularly direct digital detector has higher x-ray absorption efficiency than screen-film combination or imaging plate (IP). We measured average glandular doses (ADG) in screen-film mammography (SFM) system with slow screen-film combination, computed mammography (CM) system, indirect digital mammography (IDM) system and direct digital mammography (DDM) system using breast tissue-equivalent phantom (glandularity 30%, 50% and 70%). The results were shown as follows: AGD values for DDM system were highest than those for other systems. Although automatic exposure control (AEC) mode was selected, the curve of the AGD values against thickness or glandularity increased significantly for the SFM system with the uniform target/filter (Mo/Mo) combination. Therefore, the AGD values for the high energy examinations were highest in the SFM system, and those for the low energy examinations were highest in the DDM system. But the curve of the AGD values against thickness and glandularity increased gently for CM system with the automatic selection of the target/filter combination (from Mo/Mo to Mo/Rh or from Mo/Rh to Rh/Rh), and the AGD values were lowest. Consequently, the parameters in mammography for each exposure besides detection efficiency play an important role in order to estimate a patient radiation dose

Perspectives of Mobile Versus Fixed Mammography in Santa Clara County, California: A Focus Group Study.

Science.gov (United States)

Chen, Yi-Ren; Chang-Halpenny, Christine; Kumarasamy, Narmadan A; Venegas, Angela; Braddock Iii, Clarence H

2016-02-12

Our aim was to examine underserved women's perceptions on mobile versus fixed mammography in Santa Clara, California through a focus group study.  Research has shown that medically underserved women have higher breast cancer mortality rates correlated with under-screening and a disproportional rate of late-stage diagnosis. The Community Health Partnership in Santa Clara County, California runs the Community Mammography Access Project (CMAP) that targets nearly 20,000 medically underserved women over the age of 40 in the county through the collaborative effort of an existing safety net of healthcare providers. However, little data exists on the advantages or disadvantages of mobile mammography units from the patient perspective.   We assessed underserved women's perspectives on mammography services in Santa Clara County through two focus groups from women screened at mobile or fixed site programs. Patients were recruited from both CMAP clinics and a county hospital, and focus group data were analyzed using content analysis.  We found that women from both the mobile and fixed sites shared similar motivating factors for getting a mammogram. Both groups recognized that screening was uncomfortable but necessary for good health and had positive feedback about their personal physicians. However, mobile participants, in particular, appreciated the atmosphere of mobile screening, reported shorter wait times, and remarked on the good communication from the clinic staff and empathetic treatment they received. However, mobile participants also expressed concern about the quality of films at mobile sites due to delayed initial reading of the films.   Mobile mammography offers a unique opportunity for women of underserved populations to access high satisfaction screenings, and it encourages a model similar to CMAP in other underserved areas. However, emphasis should be placed on providing a warm and welcoming environment for patients and ensuring the quality of

Quality control of physician-performed mammography. Importance of original attempts to improve quality

International Nuclear Information System (INIS)

Nakayama, Takashi; Terada, Hiroshi; Kotsuma, Yoshikazu

2006-01-01

In order to perform effective breast cancer screening with mammography, family doctors should be encouraged to participate. At institutions without specific radiology technicians, physicians themselves are required to perform mammography and operate the equipment, otherwise it is difficult to consistently obtain good-quality mammograms. Our institutions have been given a grade ''A'' evaluation by the Central Committee for Quality Control of Mammographic Screening (CCQCMS), due largely to our own efforts and promotion. Here we report our experience in solving a number of problems that occurred during the establishment of our system. We used the SEPIO standard mammography apparatus with a MD-100/CM-H screen/filter system, and developed films using a TCX-202 automatic film processor. Problems due to asymmetry of the bilateral breasts and lack of retroglandular fat tissue space and inframammary folds seen on our initial mammograms were overcome by placing marks at the postion of the AEC sensor, and at both ends and the center of the film on a bucky table. We simplified the markers by removing several complicated ones. We tried to rectify areas of the image that were obscured due to the difference in size between the inside of the cassette and the screen. Physicians and a radiology technician attended a mammography study course once weekly, and attempted to improve the quality of mammograms and our reading ability by obtaining advice from members of the CCQCMS. Manufacturers responded with considerable delay to our attempt to overcome the troublesome appearance of numerous microcalfication-like artifact shadows caused by screens. In conclusion, in order to perform effective breast cancer screening with mammography, we must obtain mammograms of good quality, for which it is necessary to always try to seek new ways of improving. At the same time, manufacturers need to respond quickly to queries and problems related to quality control. (author)

One more hurdle to increasing mammography screening: pubescent, adolescent, and prior mammography screening experiences.

Science.gov (United States)

Thomas, Eileen; Usher, LaToya

2009-01-01

Approximately $8.1 billion dollars is spent each year in the United States alone on the treatment of breast cancer. Survival rates are dependent on access to, and utilization of, early detection services. The primary reason for disparity in breast cancer mortality is the delay in time to diagnosis, resulting in poor prognosis. Despite ongoing research to understand barriers to mammography screening, recent studies report a decrease in mammography screening among all racial groups. A qualitative approach was used to elicit information from 36 White non- Hispanic, African-American, Hispanic, and Native American women without a history of breast cancer. Women were invited to share written or audiotape-recorded narratives about experiences pertaining to their breasts and their mammography screening experiences. Major categories identified were: teasing, family norms and values, media/societal influence, body image, and mammography screening experiences. The resulting effects of these experiences left these women with feelings of shame and "conflict" regarding their breasts. The major theme identified was breast conflict. Findings suggest that breast conflict may persist throughout the lifespan and can have a negative influence on a woman's decision to participate in mammography screening. The authors hypothesize that experiences that occur during adolescence pertaining to young girls' breasts can influence a women's body image, which in turn can later in life affect health-seeking behaviors related to mammography screening. These findings have implications for public health practice in planning for breast cancer screening, education, and interventions for women from diverse racial/ethnics groups.

Effects of a risk-based online mammography intervention on accuracy of perceived risk and mammography intentions.

Science.gov (United States)

Seitz, Holli H; Gibson, Laura; Skubisz, Christine; Forquer, Heather; Mello, Susan; Schapira, Marilyn M; Armstrong, Katrina; Cappella, Joseph N

2016-10-01

This experiment tested the effects of an individualized risk-based online mammography decision intervention. The intervention employs exemplification theory and the Elaboration Likelihood Model of persuasion to improve the match between breast cancer risk and mammography intentions. 2918 women ages 35-49 were stratified into two levels of 10-year breast cancer risk (<1.5%; ≥1.5%) then randomly assigned to one of eight conditions: two comparison conditions and six risk-based intervention conditions that varied according to a 2 (amount of content: brief vs. extended) x 3 (format: expository vs. untailored exemplar [example case] vs. tailored exemplar) design. Outcomes included mammography intentions and accuracy of perceived breast cancer risk. Risk-based intervention conditions improved the match between objective risk estimates and perceived risk, especially for high-numeracy women with a 10-year breast cancer risk ≤1.5%. For women with a risk≤1.5%, exemplars improved accuracy of perceived risk and all risk-based interventions increased intentions to wait until age 50 to screen. A risk-based mammography intervention improved accuracy of perceived risk and the match between objective risk estimates and mammography intentions. Interventions could be applied in online or clinical settings to help women understand risk and make mammography decisions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

3.0 Tesla breast magnetic resonance imaging in patients with nipple discharge when mammography and ultrasound fail.

Science.gov (United States)

Lubina, Nóra; Schedelbeck, Ulla; Roth, Anne; Weng, Andreas Max; Geissinger, Eva; Hönig, Arnd; Hahn, Dietbert; Bley, Thorsten Alexander

2015-05-01

To compare 3.0 Tesla breast magnetic resonance imaging (MRI) with galactography for detection of benign and malignant causes of nipple discharge in patients with negative mammography and ultrasound. We prospectively evaluated 56 breasts of 50 consecutive patients with nipple discharge who had inconspicuous mammography and ultrasound, using 3.0 Tesla breast MRI with a dedicated 16-channel breast coil, and then compared the results with galactography. Histopathological diagnoses and follow-ups were used as reference standard. Lesion size estimated on MRI was compared with the size at histopathology. Sensitivity and specificity of MRI vs. galactography for detecting pathologic findings were 95.7 % vs. 85.7 % and 69.7 % vs. 33.3 %, respectively. For the supposed concrete pathology based on MRI findings, the specificity was 67.6 % and the sensitivity 77.3 % (PPV 60.7 %, NPV 82.1 %). Eight malignant lesions were detected (14.8 %). The estimated size at breast MRI showed excellent correlation with the size at histopathology (Pearson's correlation coefficient 0.95, p 3.0 Tesla is an accurate imaging test and can replace galactography in the workup of nipple discharge in patients with inconspicuous mammography and ultrasound. • Breast MRI is an excellent diagnostic tool for patients with nipple discharge. • MRI of the breast reveals malignant lesions despite inconspicuous mammography and ultrasound. • MRI of the breast has greater sensitivity and specificity than galactography. • Excellent correlation of lesion size measured at MRI and histopathology was found.

Quantitative breast density analysis using tomosynthesis and comparison with MRI and digital mammography.

Science.gov (United States)

Moon, Woo Kyung; Chang, Jie-Fan; Lo, Chung-Ming; Chang, Jung Min; Lee, Su Hyun; Shin, Sung Ui; Huang, Chiun-Sheng; Chang, Ruey-Feng

2018-02-01

Breast density at mammography has been used as markers of breast cancer risk. However, newly introduced tomosynthesis and computer-aided quantitative method could provide more reliable breast density evaluation. In the experiment, 98 tomosynthesis image volumes were obtained from 98 women. For each case, an automatic skin removal was used and followed by a fuzzy c-mean (FCM) classifier which separated the fibroglandular tissues from other tissues in breast area. Finally, percent of breast density and breast volume were calculated and the results were compared with MRI. In addition, the percent of breast density and breast area of digital mammography calculated using the software Cumulus (University of Toronto, Toronto, ON, Canada.) were also compared with 3-D modalities. Percent of breast density and breast volume, which were computed from tomosynthesis, MRI and digital mammography were 17.37% ± 4.39% and 607.12 cm 3  ± 323.01 cm 3 , 20.3% ± 8.6% and 537.59 cm 3  ± 287.74 cm 3 , and 12.03% ± 4.08%, respectively. There were significant correlations on breast density as well as volume between tomosynthesis and MRI (R = 0.482 and R = 0.805), tomosynthesis and breast density with breast area of digital mammography (R = 0.789 and R = 0.877), and MRI and breast density with breast area of digital mammography (R = 0.482 and R = 0.857) (all P values density and breast volume evaluated from tomosynthesis, MRI and breast density and breast area of digital mammographic images have significant correlations and indicate that tomosynthesis could provide useful 3-D information on breast density through proposed method. Copyright © 2017 Elsevier B.V. All rights reserved.

Mammography: MedlinePlus Health Topic

Science.gov (United States)

... Questions (National Cancer Institute) Mammography for Women with Breast Implants (American Cancer Society) Also in Spanish Mammography: What You Need to Know (Food and Drug Administration) Nipple Aspirate Test Is ... Specifics Breast Tomosynthesis (American College of Radiology, Radiological Society of ...

Application of phase contrast imaging to mammography

International Nuclear Information System (INIS)

Tohyama, Keiko; Yamada, Katsuhiko; Katafuchi, Tetsuro; Matsuo, Satoru; Morishita, Junji

2005-01-01

Phase contrast images were obtained experimentally by using a customized mammography unit with a nominal focal spot size of 100 μm and variable source-to-image distances of up to 1.5 m. The purpose of this study was to examine the applicability and potential usefulness of phase contrast imaging for mammography. A mammography phantom (ACR156 RMI phantom) was imaged, and its visibility was examined. The optical density of the phantom images was adjusted to approximately 1.3 for both the contact and phase contrast images. Forty-one observers (18 medical doctors and 23 radiological technologists) participated in visual evaluation of the images. Results showed that, in comparison with the images of contact mammography, the phantom images of phase contrast imaging demonstrated statistically significantly superior visibility for fibers, clustered micro-calcifications, and masses. Therefore, phase contrast imaging obtained by using the customized mammography unit would be useful for improving diagnostic accuracy in mammography. (author)

[Effect of Reading a Book on a Tablet Computer on Cerebral Blood Flow in the Prefrontal Cortex].

Science.gov (United States)

Sugiura, Akihiro; Eto, Takuya; Kinoshita, Fumiya; Takada, Hiroki

2018-01-01

By measuring cerebral blood flow in the prefrontal cortex, we aimed to determine how reading a book on a tablet computer affects sleep. Seven students (7 men age range, 21-32 years) participated in this study. In a controlled illuminance environment, the subjects read a novel in printed form or on a tablet computer from any distance. As the subjects were reading, the cerebral blood flow in their prefrontal cortex was measured by near-infrared spectroscopy. The study protocol was as follows. 1) Subjects mentally counted a sequence of numbers for 30 s as a pretest to standardized thinking and then 2) read the novel for 10 min, using the printed book or tablet computer. In step 2), the use of the book or tablet computer was in a random sequence. Subjects rested between the two tasks. Significantly increased brain activity (increase in regional cerebral blood flow) was observed following reading a novel on a tablet computer compared with that after reading a printed book. Furthermore, the region around Broca's area was more active when reading on a tablet computer than when reading a printed book. Considering the results of this study and previous studies on physiological characteristics during nonrapid eye movement sleep, we concluded that reading a book on a tablet computer before the onset of sleep leads to the potential inhibition of sound sleep through mechanisms other than the suppression of melatonin secretion.

Mammography

Science.gov (United States)

... breast cancer Whether there is any harm from breast cancer screening, such as side effects from testing or overtreatment of cancer when it's discovered Mammography is performed to screen women to detect early breast cancer when it is ...

Clinical evaluation of contrast-enhanced digital mammography and contrast enhanced tomosynthesis--Comparison to contrast-enhanced breast MRI.

Science.gov (United States)

Chou, Chen-Pin; Lewin, John M; Chiang, Chia-Ling; Hung, Bao-Hui; Yang, Tsung-Lung; Huang, Jer-Shyung; Liao, Jia-Bin; Pan, Huay-Ben

2015-12-01

To compare the diagnostic accuracy of contrast-enhanced digital mammography (CEDM) and contrast-enhanced tomosynthesis (CET) to dynamic contrast enhanced breast MRI (DCE-MRI) using a multireader-multicase study. Institutional review board approval and informed consents were obtained. Total 185 patients (mean age 51.3) with BI-RADS 4 or 5 lesions were evaluated before biopsy with mammography, tomosynthesis, CEDM, CET and DCE-MRI. Mediolateral-oblique and cranio-caudal views of the target breast CEDM and CET were acquired at 2 and 4 min after contrast agent injection. A mediolateral-oblique view of the non-target breast was taken at 6 min. Each lesion was scored with forced BI-RADS categories by three readers. Each reader interpreted lesions in the following order: mammography, tomosynthesis, CEDM, CET, and DCE-MRI during a single reading session. Histology showed 81 cancers and 144 benign lesions in the study. Of the 81 malignant lesions, 44% (36/81) were invasive and 56% (45/81) were non-invasive. Areas under the ROC curve, averaged for the 3 readers, were as follows: 0.897 for DCE-MRI, 0.892 for CET, 0.878 for CEDM, 0.784 for tomosynthesis and 0.740 for mammography. Significant differences in AUC were found between the group of contrast enhanced modalities (CEDM, CET, DCE-MRI) and the unenhanced modalities (all p0.05). CET and CEDM may be considered as an alternative modality to MRI for following up women with abnormal mammography. All three contrast modalities were superior in accuracy to conventional digital mammography with or without tomosynthesis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cost-effectiveness of increasing access to mammography through mobile mammography for older women.

Science.gov (United States)

Naeim, Arash; Keeler, Emmett; Bassett, Lawrence W; Parikh, Jay; Bastani, Roshan; Reuben, David B

2009-02-01

To compare the costs of mobile and stationary mammography and examine the incremental cost-effectiveness of using mobile mammography to increase screening rates. A cost-effectiveness analysis was performed using effectiveness data from a randomized clinical trial and modeling of costs associated with the mobile mammography intervention. The trial involved 60 community-based meal sites, senior centers, and clubs. Four hundred ninety-nine individuals were enrolled in the study, of whom 463 had outcome data available for analysis. Costs were calculated for stationary and mobile mammography, as well as costs due to differences in technology and film versus digital. Incremental cost-effectiveness (cost per additional screen) was modeled, and sensitivity analysis was performed by altering efficiency (throughput) and effectiveness based on subgroup data from the randomized trial. The estimated annual costs were $435,162 for a stationary unit, $539,052 for a mobile film unit, and $456, 392 for a mobile digital unit. Assuming mobile units are less efficient (50% annual volume), the cost per screen was $41 for a stationary unit, $86 for a mobile film unit, and $102 for a mobile digital unit. The incremental cost per additional screen were $207 for a mobile film unit and $264 for a mobile digital unit over a stationary unit. Although mobile mammography is a more effective way to screen older women, the absolute cost per screen of mobile units is higher, whereas the reimbursement is no different. Financial barriers may impede the widespread use of this approach.

Digital information management: a progress report on the National Digital Mammography Archive

Science.gov (United States)

Beckerman, Barbara G.; Schnall, Mitchell D.

2002-05-01

Digital mammography creates very large images, which require new approaches to storage, retrieval, management, and security. The National Digital Mammography Archive (NDMA) project, funded by the National Library of Medicine (NLM), is developing a limited testbed that demonstrates the feasibility of a national breast imaging archive, with access to prior exams; patient information; computer aids for image processing, teaching, and testing tools; and security components to ensure confidentiality of patient information. There will be significant benefits to patients and clinicians in terms of accessible data with which to make a diagnosis and to researchers performing studies on breast cancer. Mammography was chosen for the project, because standards were already available for digital images, report formats, and structures. New standards have been created for communications protocols between devices, front- end portal and archive. NDMA is a distributed computing concept that provides for sharing and access across corporate entities. Privacy, auditing, and patient consent are all integrated into the system. Five sites, Universities of Pennsylvania, Chicago, North Carolina and Toronto, and BWXT Y12, are connected through high-speed networks to demonstrate functionality. We will review progress, including technical challenges, innovative research and development activities, standards and protocols being implemented, and potential benefits to healthcare systems.

Study on patient exposure from mammography, 3

International Nuclear Information System (INIS)

Sato, Miyao

1983-01-01

Risks and benefits of the patient from mammography performed in Japan were estimated, and the indication of mammography were discussed. 1) Breast cancers induced by mammography were estimated based on the average breast dose, the average life span, risks of radiation-induced breast cancer and the breast cancer significant factor. 2) The breast cancer significant factor was calculated, similar to those of leukemia significant factor by Hashizume, from latent periods of radiation-induced breast cancer and the excess breast cancer induction rate in female A-bomb survivors. 3) Numbers of the deaths and Lost-years were calculated from risks of radiation-induced breast cancer, incidence of breast cancer by mammography, cure rate of breast cancer, average life span and latent period of radiation-induced breast cancer. 4) Numbers of the increased life and years saved were calculated from the improved rate of the ability of diagnosis, frequency of mammography, the average life span and cure rate of breast cancer. 5) Induction of leukemia, lung cancer and thyroid cancer by mammography also were investigated. Its contribution was not significant, compared to the induction of breast cancer. 6) Comparing risk and benefit, the latter was much higher than the former by factors of 71-76. This was suggested the efficacy of mammography. 7) From a pointview of risk and benefit, routine mammography is contraindicative for 10-19 years old women because of large risk, the indication must be scrutinized for 20-29 years old ones, and the benefit increases with age for over 30 years old ones so that mammography was positively admitted for the symptomatic women. (author)

A study of quality assurance in mammography

International Nuclear Information System (INIS)

Briquet, Claudia; Mota, Helvecio C.; Costa, Marcos R.

1997-01-01

Full text. Nowadays mammography has two definitive important roles: as a complementary tool to confirm clinical findings and for the detection of early breast cancer. To reach and maintain the standards of image quality within the frontiers of reasonable radiation doses, the facilities must follow a QA program. The objective of this study is to accomplish such a program in three school hospitals in Rio de Janeiro. We made assessment of clinical images using the Accreditation American Phantom and measured the patients skin entrance doses with TLD 100. In each facility we evaluated the technical parameters of the mammographic units using a Victoreen 4000 M+ and an evaluation of the compression devices. The 3 hospitals studied use film and screen Min R Kodak and have Kodak processors, none of them dedicated to mammograms. The tube voltage, measured was not significantly different from the indicated values, the variations were lesser than 5%. In one of the hospitals the kVp did not show reproducibility, the coefficient of variation was too high - 1,02. The same facility showed an exposure time with variation of 7% and we asked for corrective action. Measures of HVL showed the same value for the 3 hospitals the compression were adequate. The patients skin entrance doses were measured with TLD 100 and showed the range 3,25 a 10,26 mGy. This range is due to differences in density and thickness of the breast. The doses values were in accordance with the Quality Criteria for Mammography of the Commission of the European Communities

Does gender discrimination impact regular mammography screening? Findings from the race differences in screening mammography study.

Science.gov (United States)

Dailey, Amy B; Kasl, Stanislav V; Jones, Beth A

2008-03-01

ABSTRACT Objective: To determine if gender discrimination, conceptualized as a negative life stressor, is a deterrent to adherence to mammography screening guidelines. African American and white women (1451) aged 40-79 years who obtained an index screening mammogram at one of five urban hospitals in Connecticut between October 1996 and January 1998 were enrolled in this study. This logistic regression analysis includes the 1229 women who completed telephone interviews at baseline and follow-up (average 29.4 months later) and for whom the study outcome, nonadherence to age-specific mammography screening guidelines, was determined. Gender discrimination was measured as lifetime experience in seven possible situations. Gender discrimination, reported by nearly 38% of the study population, was significantly associated with nonadherence to mammography guidelines in women with annual family incomes of > or =$50,000 (OR 1.99, 95% CI 1.33, 2.98) and did not differ across racial/ethnic group. Our findings suggest that gender discrimination can adversely influence regular mammography screening in some women. With nearly half of women nonadherent to screening mammography guidelines in this study and with decreasing mammography rates nationwide, it is important to address the complexity of nonadherence across subgroups of women. Life stressors, such as experiences of gender discrimination, may have considerable consequences, potentially influencing health prevention prioritization in women.

Family/Friend Recommendations and Mammography Intentions: The Roles of Perceived Mammography Norms and Support

Science.gov (United States)

Molina, Yamile; Ornelas, India J.; Doty, Sarah L.; Bishop, Sonia; Beresford, Shirley A. A.; Coronado, Gloria D.

2015-01-01

Identifying factors that increase mammography use among Latinas is an important public health priority. Latinas are more likely to report mammography intentions and use, if a family member or friend recommends that they get a mammogram. Little is known about the mechanisms underlying the relationship between social interactions and mammography…

Contrast-enhanced spectral mammography vs. mammography and MRI - clinical performance in a multi-reader evaluation

NARCIS (Netherlands)

Fallenberg, E.M.; Schmitzberger, F.F.; Amer, H.; Ingold-Heppner, B.; Balleyguier, C.; Diekmann, F.; Engelken, F.; Mann, R.M.; Renz, D.M.; Bick, U.; Hamm, B.; Dromain, C.

2017-01-01

OBJECTIVES: To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) to digital mammography (MG) and magnetic resonance imaging (MRI) in a prospective two-centre, multi-reader study. METHODS: One hundred seventy-eight women (mean age 53 years) with invasive breast

Slit aperture technique for mammography

International Nuclear Information System (INIS)

Friedrich, M.

1984-01-01

Following a discussion of various principles used in the elimination of scatter, the prototype of a simple slit aperture mammography apparatus is described (modified Mammomat, Siemens). The main advantage of this technique compared with grid mammography is a halving of the radiation dose for identical image quality, using an identical film system. The technical requirements (heavy duty tube, new generator) are, however, considerable. If the film-screen systems currently in use are to remain the common systems for the future, then the development of a multi-lamellar slit diaphragm technique carries much promise for mammography. (orig.) [de

Digital mammography and their developments

International Nuclear Information System (INIS)

Wienbeck, Susanne

2015-01-01

At the present time digital mammography is a satisfactory breast diagnostic imaging in clinical as well as screening mammography in defined age groups. Nevertheless it shows beside the application of ionizing radiation in women with dense breasts limitations in the detection of non calcification breast cancers. Tomosynthesis, digital contrast-enhanced mammography and breast-CT with or without contrast media lead to better results. Especially the application of contrast media for the visualisation of the tumor angiogenesis is invariably superior to all other non-contrast imaging modalities. However, the excellent results of breast MRI will be probably accessible with none of the new procedures.

MO-AB-207-00: ACR Update in MR, CT, Nuclear Medicine, and Mammography

International Nuclear Information System (INIS)

2015-01-01

A goal of an imaging accreditation program is to ensure adequate image quality, verify appropriate staff qualifications, and to assure patient and personnel safety. Currently, more than 35,000 facilities in 10 modalities have been accredited by the American College of Radiology (ACR), making the ACR program one of the most prolific accreditation options in the U.S. In addition, ACR is one of the accepted accreditations required by some state laws, CMS/MIPPA insurance and others. Familiarity with the ACR accreditation process is therefore essential to clinical diagnostic medical physicists. Maintaining sufficient knowledge of the ACR program must include keeping up-to-date as the various modality requirements are refined to better serve the goals of the program and to accommodate newer technologies and practices. This session consists of presentations from authorities in four ACR accreditation modality programs, including magnetic resonance imaging, computed tomography, nuclear medicine, and mammography. Each speaker will discuss the general components of the modality program and address any recent changes to the requirements. Learning Objectives: To understand the requirements of the ACR MR Accreditation program. The discussion will include accreditation of whole-body general purpose magnets, dedicated extremity systems well as breast MRI accreditation. Anticipated updates to the ACR MRI Quality Control Manual will also be reviewed. To understand the requirements of the ACR CT accreditation program, including updates to the QC manual as well as updates through the FAQ process. To understand the requirements of the ACR nuclear medicine accreditation program, and the role of the physicist in annual equipment surveys and the set up and supervision of the routine QC program. To understand the current ACR MAP Accreditation requirement and present the concepts and structure of the forthcoming ACR Digital Mammography QC Manual and Program

MO-AB-207-00: ACR Update in MR, CT, Nuclear Medicine, and Mammography

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-06-15

A goal of an imaging accreditation program is to ensure adequate image quality, verify appropriate staff qualifications, and to assure patient and personnel safety. Currently, more than 35,000 facilities in 10 modalities have been accredited by the American College of Radiology (ACR), making the ACR program one of the most prolific accreditation options in the U.S. In addition, ACR is one of the accepted accreditations required by some state laws, CMS/MIPPA insurance and others. Familiarity with the ACR accreditation process is therefore essential to clinical diagnostic medical physicists. Maintaining sufficient knowledge of the ACR program must include keeping up-to-date as the various modality requirements are refined to better serve the goals of the program and to accommodate newer technologies and practices. This session consists of presentations from authorities in four ACR accreditation modality programs, including magnetic resonance imaging, computed tomography, nuclear medicine, and mammography. Each speaker will discuss the general components of the modality program and address any recent changes to the requirements. Learning Objectives: To understand the requirements of the ACR MR Accreditation program. The discussion will include accreditation of whole-body general purpose magnets, dedicated extremity systems well as breast MRI accreditation. Anticipated updates to the ACR MRI Quality Control Manual will also be reviewed. To understand the requirements of the ACR CT accreditation program, including updates to the QC manual as well as updates through the FAQ process. To understand the requirements of the ACR nuclear medicine accreditation program, and the role of the physicist in annual equipment surveys and the set up and supervision of the routine QC program. To understand the current ACR MAP Accreditation requirement and present the concepts and structure of the forthcoming ACR Digital Mammography QC Manual and Program.

Data acquisition electronics for positron emission mammography (PEM) detectors

International Nuclear Information System (INIS)

Martinez, J.D.; Sebastia, A.; Cerda, J.; Esteve, R.; Mora, F.J.; Toledo, J.F.; Benlloch, J.M.; Gimenez, N.; Gimenez, M.; Lerche, Ch. W.; Pavon, N.; Sanchez, F.

2005-01-01

Positron emission mammography (PEM) is an innovative technique to increase sensitivity and overcome the main drawbacks of conventional X-ray screening. However, dedicated PET imaging systems demand specific hardware solutions for data acquisition and processing that can take advantage of the reduction in the number of channels. Data acquisition issues can affect PEM scanners performance and they should be exhaustively addressed in order to exploit the increment in the event count rate. This is crucial in order to reduce both the scanning time and the total injected dose. This paper presents the electronics for our PEM camera prototype that enables us to achieve very high-count rates and perform comprehensive online processing. Results about acquisition in our detector for a typical clinical setup are studied using Monte Carlo simulation of hot lesion phantoms

Quality control for the mammography screening program in Serbia: Physical and technical aspects

International Nuclear Information System (INIS)

Ciraj-Bjelac, O.; Bozovic, P.; Lazarevic, D.; Arandjic, D.; Kosutic, D.

2012-01-01

Breast cancer is the major cause of mortality among female population in Serbia. It is presumed that the introduction of screening programme will reduce mortality and therefore, 47 new mammography units were installed for the purpose of population-based screening program in 2011. In parallel, Quality assurance and Quality control (QC) in mammography has received increasing attention as an essential element of the successful breast cancer campaign that is for the first time initialed in Serbia. The purpose of this study is to investigate the need for and the possible implementation of the comprehensive QC programme for the mammography screening in Serbia, with special focus on physical and technical aspect. In the first phase, a QC protocols containing list of parameters, methodology, frequency of tests and reference values for screen-film, computed radiography and full-filed digital mammography) units, were developed. The second phase is focused on the initial implementation of these protocols. The paper presents results of tests of the selected parameters in 35 mammography units, with special emphasis on patient dose and image quality descriptors. After initial implementation at the beginning of the population based breast cancer screening campaign, it is essential to establish system of regular and periodic QC equipment monitoring and to ensure high quality mammograms with minimal possible radiation dose to population included in the screening. (authors)

Energy Secretary Dedicates ESIF at NREL | News | NREL

Science.gov (United States)

3 » Energy Secretary Dedicates ESIF at NREL Energy Secretary Dedicates ESIF at NREL September 18 prey. Enlarge image Energy Secretary Ernest Moniz (center) joins NREL Director Dan Arvizu (left) and newest Energy Department supercomputer. The high performance computer inside NREL's new Energy Systems

Comparative evaluation of average glandular dose and image of digital mammography and film mammography in Minas Gerais, Brazil

International Nuclear Information System (INIS)

Nogueira, M.; Leyton, F.; Rodrigue, L. L.C.; Oliveira, M.A.; Joana, G.S.; Silva, S.D.

2015-01-01

Breast cancer is the most common cancer among women, and early detection is critical to its diagnosis and treatment. Mammography is the best method for breast-cancer screening and is capable of reducing mortality rates To date, the most effective method for early detection of breast cancer has been x-ray mammography for which the screen/film (SF) technique has been the gold standard. Digital mammography has been proposed as a substitute for film mammography given the benefits inherent to digital technology. The purpose of our study was to compare the technical performance of digital mammographic and screen-film mammography. A PMMA phantom with objects to simulate breast structures. For the screen/film (SF) technique the results showed that 54% mammography units did not achieve the minimum acceptable performance as far the image quality. Besides, 67% services showed inadequate performance in their processing systems, which had significant influence on the image quality. At the mean glandular dose only 44% of digital systems evaluated were compliant in all thicknesses of PMMA. The average glandular dose AGD was 90 % higher than in screen/film systems. (authors)

3.0 Tesla breast magnetic resonance imaging in patients with nipple discharge when mammography and ultrasound fail

Energy Technology Data Exchange (ETDEWEB)

Lubina, Nora; Schedelbeck, Ulla; Weng, Andreas Max; Hahn, Dietbert; Bley, Thorsten Alexander [University of Wuerzburg, Department of Diagnostic and Interventional Radiology, Wuerzburg (Germany); Roth, Anne [Centre of Radiology Wuerzburg, Wuerzburg (Germany); Geissinger, Eva [University of Wuerzburg, Institute of Pathology, Wuerzburg (Germany); Hoenig, Arnd [Catholic Clinical Centre Mainz, Department of Obstetrics and Gynecology, Mainz (Germany)

2015-05-01

To compare 3.0 Tesla breast magnetic resonance imaging (MRI) with galactography for detection of benign and malignant causes of nipple discharge in patients with negative mammography and ultrasound. We prospectively evaluated 56 breasts of 50 consecutive patients with nipple discharge who had inconspicuous mammography and ultrasound, using 3.0 Tesla breast MRI with a dedicated 16-channel breast coil, and then compared the results with galactography. Histopathological diagnoses and follow-ups were used as reference standard. Lesion size estimated on MRI was compared with the size at histopathology. Sensitivity and specificity of MRI vs. galactography for detecting pathologic findings were 95.7 % vs. 85.7 % and 69.7 % vs. 33.3 %, respectively. For the supposed concrete pathology based on MRI findings, the specificity was 67.6 % and the sensitivity 77.3 % (PPV 60.7 %, NPV 82.1 %). Eight malignant lesions were detected (14.8 %). The estimated size at breast MRI showed excellent correlation with the size at histopathology (Pearson's correlation coefficient 0.95, p < 0.0001). MRI of the breast at 3.0 Tesla is an accurate imaging test and can replace galactography in the workup of nipple discharge in patients with inconspicuous mammography and ultrasound. (orig.)

Image quality in mammography

International Nuclear Information System (INIS)

Haus, A.G.; Doi, K.; Metz, C.E.; Bernstein, J.

1976-01-01

In mammography, image quality is a function of the shape, size, and x-ray absorption properties of the anatomic part to be radiographed and of the lesion to be detected; it also depends on geometric unsharpness, and the resolution, characteristic curve and noise properties of the recording system. X-ray energy spectra, modulation transfer functions, Wiener spectra, characteristic and gradient curves, and radiographs of a breast phantom and of a resected breast specimen containing microcalcifications are used in a review of some current considerations of the factors, and the complex relationship among factors, that affect image quality in mammography. Image quality and patient radiation exposure in mammography are interrelated. An approach to the problem of evaluating the trade-off between diagnostic certainty and the cost or risk of performing a breast imaging procedure is discussed

Teaching syllabus for radiological aspects of breast cancer screening with digital mammography

International Nuclear Information System (INIS)

Van Ongeval, C.; Van Steen, A.; Bosmans, H.

2008-01-01

The purpose of this study is to discuss the content of our new accreditation programme for radiologists' reading digital mammograms in a screening setting and to report our first experience with the new course. The course consisted of a theoretical part, given by the medical physicist, and a practical part given by the radiologist. The practical session is closely linked with the theoretical part and a reading session. The material is fully digital and can be presented on different platforms. In practice, the need for parallel soft-copy reading sessions on high-end workstations limits the number of participants. A high level of interactivity was noted between teacher and participant, with a thorough discussion of different digital mammography systems during a single teaching course. The main challenge for the teacher turned out to be the collection of representative material and the continuous updating of the material: new systems, processing techniques and artefacts need to be included regularly. (authors)

Evidence on Synthesized Two-dimensional Mammography Versus Digital Mammography When Using Tomosynthesis (Three-dimensional Mammography) for Population Breast Cancer Screening.

Science.gov (United States)

Houssami, Nehmat

2017-09-28

One limitation of using digital breast tomosynthesis (3-dimensional [3D] mammography) technology with conventional (2-dimensional [2D]) mammography for breast cancer (BC) screening is the increased radiation dose from dual acquisitions. To resolve this problem, synthesized 2D (s2D) reconstruction images similar to 2D mammography were developed using tomosynthesis acquisitions. The present review summarizes the evidence for s2D versus digital mammography (2D) when using tomosynthesis (3D) for BC screening to address whether using s2D instead of 2D (alongside 3D) will yield similar detection measures. Comparative population screening studies have provided consistent evidence that cancer detection rates do not differ between integrated 2D/3D (range, 5.45-8.5/1000 screens) and s2D/3D (range, 5.03-8.8/1000 screens). Also, although the recall measures were relatively heterogeneous across included studies, little difference was found between the 2 modalities. The mean glandular dose for s2D/3D was 55% to 58% of that for 2D/3D. In the context of BC screening, s2D/3D involves substantially less radiation than 2D/3D and provides similar detection measures. Thus, consideration of transitioning to tomosynthesis screening should aim to use s2D/3D to minimize harm. Copyright © 2017 Elsevier Inc. All rights reserved.

Development of an excel spreadsheet formean glandular dose in mammography

International Nuclear Information System (INIS)

Nagoshi, Kazuyo; Fujisaki, Tatsuya

2008-01-01

The purpose of this study was to develop an Excel spreadsheet to calculate mean glandular dose (D g ) in mammography using clinical exposure data. D g can be calculated as the product of incident air kerma (K a ) and D gN (i.e., D g =K a x D gN ). According to the method of Klein et al (Phys Med Biol 1997; 42: 651-671), K a was measured at the entrance surface with an ionization dosimeter. Normalized glandular dose (D gN ) coefficients, taking into account breast glandularity, were computed using Boone's method (Med Phys 2002; 29: 869-875). D gN coefficients can be calculated for any arbitrary X-ray spectrum. These calculation procedures were input into a Microsoft Excel spreadsheet. The resulting Excel spreadsheet is easy to use and is always applicable in the field of mammography. The exposure conditions concerning D g in clinical practice were also investigated in 22 women. Four exposure conditions (target/filter combination and tube voltage) were automatically selected in this study. This investigation found that average D g for each exposure was 1.9 mGy. Because it is recommended that quality control of radiation dose management in mammography is done using an American College of Radiology (ACR) phantom, information about patient dose is not obtained in many facilities. The present Excel spreadsheet was accordingly considered useful for optimization of exposure conditions and explanation of mammography to patients. (author)

Dual-energy contrast-enhanced mammography.

Science.gov (United States)

Travieso Aja, M M; Rodríguez Rodríguez, M; Alayón Hernández, S; Vega Benítez, V; Luzardo, O P

2014-01-01

The degree of vascularization in breast lesions is related to their malignancy. For this reason, functional diagnostic imaging techniques have become important in recent years. Dual-energy contrast-enhanced mammography is a new, apparently promising technique in breast cancer that provides information about the degree of vascularization of the lesion in addition to the morphological information provided by conventional mammography. This article describes the state of the art for dual-energy contrast-enhanced mammography. Based on 15 months' clinical experience, we illustrate this review with clinical cases that allow us to discuss the advantages and limitations of this technique. Copyright © 2014 SERAM. Published by Elsevier Espana. All rights reserved.

Digital versus screen-film mammography: impact of mammographic density and hormone therapy on breast cancer detection.

Science.gov (United States)

Chiarelli, Anna M; Prummel, Maegan V; Muradali, Derek; Shumak, Rene S; Majpruz, Vicky; Brown, Patrick; Jiang, Hedy; Done, Susan J; Yaffe, Martin J

2015-11-01

Most studies that have examined the effects of mammographic density and hormone therapy use on breast cancer detection have included screen-film mammography. This study further examines this association in post-menopausal women screened by digital mammography. Approved by the University of Toronto Research Ethics Board, this study identified 688,418 women of age 50-74 years screened with digital or screen-film mammography from 2008 to 2009 within the Ontario Breast Screening Program. Of 2993 eligible women with invasive breast cancer, 2450 were contacted and 1421 participated (847 screen-film mammography, 574 digital direct radiography). Mammographic density was measured by study radiologists using the standard BI-RADS classification system and by a computer-assisted method. Information on hormone therapy use was collected by a telephone-administered questionnaire. Logistic regression and two-tailed tests for significance evaluated associations between factors and detection method by mammography type. Women with >75 % radiologist-measured mammographic density compared to those with diagnosed with an interval than screen-detected cancer, with the difference being greater for those screened with screen-film (OR = 6.40, 95 % CI 2.30-17.85) than digital mammography (OR = 2.41, 95 % CI 0.67-8.58) and aged 50-64 years screened with screen-film mammography (OR = 10.86, 95 % CI 2.96-39.57). Recent former hormone therapy users were also at an increased risk of having an interval cancer with the association being significant for women screened with digital mammography (OR = 2.08, 95 % CI 1.17-3.71). Breast screening using digital mammography lowers the risk of having an interval cancer for post-menopausal women aged 50-64 with greater mammographic density.

Quality control of mammography departments in Slovakia

International Nuclear Information System (INIS)

Horvathova, M.; Nikodemova, D.

2007-01-01

Complete test of publication follows. Considering the fact that mammary gland is the most sensitive organ to ionizing radiation, the Commission of the Ministry of Health of SR for QA in radiology organized a pilot two-run country wide audit conducted in 42 mammography departments that have met the beforehand criteria. During the audit the methods for establishing the individual parameters in technical and clinical part of quality assurance in mammography were elaborated and implemented. Technical and clinical parameters of the imaging process that mostly affect the quality of diagnostic information were followed up. These parameters included: the object thickness compensation, optical density deviation, evaluation of the film quality by means of special phantom, etc. Important measurement of ESDs at participating departments enabled to compare the radiation load of mammography patients in Slovakia with reference values in European guidelines. The uniform standard method for QA at mammography departments was elaborated and published as the regulation of the Ministry of Health for performance of preventive mammography examinations in SR. The presented results show the improved quality of mammography examinations due to regular check-ups of technical and clinical parameters and fulfilment of the required values in all parameters. The audit results are the basis for continuous quality assessment of mammography departments as a main prerequisite for conducting preventive examinations and for health insurance purposes.

Data on the cost-benefit analysis of mammography

International Nuclear Information System (INIS)

Zarand, P.; Pentek, Z.

1982-01-01

The radiation exposure and the cost per examination are compared in the case of three methods: non-screen film mammography, 10-dose mammography and xeromammography. 10-dose mammography results in the lowest radiation exposure whereas xeromammography has the lowest cost. (L.E.)

Advanced Breast Cancer as Indicator of Quality Mammography

International Nuclear Information System (INIS)

Gaona, Enrique

2003-01-01

Breast cancer is the most frequently diagnosed cancer and is the second leading cause of cancer death among women in the Mexican Republic. Mammography is the more important screening tool for detecting early breast cancer. Screening mammography involves taking x-rays from two views from each breast, typically from above (cranial-caudal view, CC) and from an oblique or angled view (mediolateral-oblique, MLO). The purpose of this study was to carry out an exploratory survey of the issue of patients with advanced breast cancer who have had a screening mammography. A general result of the survey is that 22.5% of all patients (102) with advanced breast cancer that participated in the study had previous screening mammography. But we should consider that 10% of breast cancers are not detected by mammography. Only 70% of the family doctors prescribed a diagnostic mammography when the first symptoms were diagnosed

Mammography Facilities

Data.gov (United States)

U.S. Department of Health & Human Services — The Mammography Facility Database is updated periodically based on information received from the four FDA-approved accreditation bodies: the American College of...

WE-FG-207A-01: Introduction to Dedicated Breast CT - Early Studies

International Nuclear Information System (INIS)

Vedantham, S.

2016-01-01

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

WE-FG-207A-01: Introduction to Dedicated Breast CT - Early Studies

Energy Technology Data Exchange (ETDEWEB)

Vedantham, S. [University of Massachusetts Medical School (United States)

2016-06-15

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

Investigation of actual conditions of mammography in Kagoshima prefecture

International Nuclear Information System (INIS)

Baba, Natsuki; Tanimoto, Eriko; Kobayashi, Yasuhiro; Kuma, Kouji

2009-01-01

We surveyed the actual conditions of mammography with regard to image quality and radiation dose at 44 facilities in Kagoshima prefecture in 1999. In April 2004, guidelines for mammography newly included the standard of digital mammography. From September to October 2005, the survey was conducted at 48 facilities, and the results of the survey were compared with that in 1999. We visited 44 of the 48 facilities, and visually evaluated the image quality of mammograms for RMI156 and clinical mammograms. In addition, we measured average mammary gland dose at each facility. The number of the mammography device that satisfied the specified guideline criterion was larger than that in 1999. Image quality for the RMI156 mammograms improved. However, the results of the present survey revealed several problems. First, the number of facilities that had quality control instruments for mammography are few. Second, radiological technologists, medical doctors, and nurses did not share knowledge or information regarding mammography. Finally, there were differences in devices and image quality for mammography among the facilities. We achieved an understanding of the actual conditions of mammography in Kagoshima prefecture by visiting many facilities, evaluating image quality, and communicating with many staff members. Our results may be useful for the development of mammography examinations. (author)

English Language Learners' Strategies for Reading Computer-Based Texts at Home and in School

Science.gov (United States)

Park, Ho-Ryong; Kim, Deoksoon

2016-01-01

This study investigated four elementary-level English language learners' (ELLs') use of strategies for reading computer-based texts at home and in school. The ELLs in this study were in the fourth and fifth grades in a public elementary school. We identify the ELLs' strategies for reading computer-based texts in home and school environments. We…

Development of a simple photon emission computed tomography dedicated to the small animal

International Nuclear Information System (INIS)

Bekaert, V.

2006-11-01

The development of in vivo small animal imaging becomes essential to study human pathologies. The ImaBio project of Institut Pluridisciplinaire Hubert Curien (IPHC) fits in the process of developing new instruments for biomedical applications with the development of a multimodality imaging platform dedicated to small animal imaging (AMISSA). This thesis presents the study, the design and the development of a Single Photon Emission Computed Tomography (SPECT) which will be integrated to the AMISSA platform. The result of these developments is the possibility to obtain the spatial distribution of an injected molecule into the animal. The SPECT technical solutions are based on the acquired knowledge of the institute allowing the conception of a device with cameras adapted to the gamma detection produced by the radiotracers used in single photon imaging. In order to cover the entire of the transverse field of view, four gamma cameras are arranged in a ring around the volume of interest. Each camera consists of 5 individual modules based on a YAP:Ce crystal array, a multi-anode photomultiplier and a dedicated multichannel electronic device. Finally, 20 detection modules were calibrated to give the same result for an identical energy deposit. The data are acquired then process to extract the positions and the energies deposited by gamma photons in the crystals. This last information is then gathered to build the projections. The 3D reconstructed image from the projections is carried out by the sequence of two algorithms, analytical and iterative OS-EM, both modified to take into account the singular geometry of our detection system. Finally, the obtained image is fused with the anatomical information given by the micro Computed Tomography system. (author)

Update on new technologies in digital mammography

Directory of Open Access Journals (Sweden)

Patterson SK

2014-08-01

Full Text Available Stephanie K Patterson, Marilyn A Roubidoux Division of Breast Imaging, Department of Radiology, University of Michigan Health System, Ann Arbor, MI, USA Abstract: Despite controversy regarding mammography's efficacy, it continues to be the most commonly used breast cancer-screening modality. With the development of digital mammography, some improved benefit has been shown in women with dense breast tissue. However, the density of breast tissue continues to limit the sensitivity of conventional mammography. We discuss the development of some derivative digital technologies, primarily digital breast tomosynthesis, and their strengths, weaknesses, and potential patient impact. Keywords: screening mammography, breast cancer, contrast media, digital breast tomosynthesis

Using computer-extracted image features for modeling of error-making patterns in detection of mammographic masses among radiology residents.

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Zhang, Jing; Lo, Joseph Y; Kuzmiak, Cherie M; Ghate, Sujata V; Yoon, Sora C; Mazurowski, Maciej A

2014-09-01

Mammography is the most widely accepted and utilized screening modality for early breast cancer detection. Providing high quality mammography education to radiology trainees is essential, since excellent interpretation skills are needed to ensure the highest benefit of screening mammography for patients. The authors have previously proposed a computer-aided education system based on trainee models. Those models relate human-assessed image characteristics to trainee error. In this study, the authors propose to build trainee models that utilize features automatically extracted from images using computer vision algorithms to predict likelihood of missing each mass by the trainee. This computer vision-based approach to trainee modeling will allow for automatically searching large databases of mammograms in order to identify challenging cases for each trainee. The authors' algorithm for predicting the likelihood of missing a mass consists of three steps. First, a mammogram is segmented into air, pectoral muscle, fatty tissue, dense tissue, and mass using automated segmentation algorithms. Second, 43 features are extracted using computer vision algorithms for each abnormality identified by experts. Third, error-making models (classifiers) are applied to predict the likelihood of trainees missing the abnormality based on the extracted features. The models are developed individually for each trainee using his/her previous reading data. The authors evaluated the predictive performance of the proposed algorithm using data from a reader study in which 10 subjects (7 residents and 3 novices) and 3 experts read 100 mammographic cases. Receiver operating characteristic (ROC) methodology was applied for the evaluation. The average area under the ROC curve (AUC) of the error-making models for the task of predicting which masses will be detected and which will be missed was 0.607 (95% CI,0.564-0.650). This value was statistically significantly different from 0.5 (perror

Colour application on mammography image segmentation

Science.gov (United States)

Embong, R.; Aziz, N. M. Nik Ab.; Karim, A. H. Abd; Ibrahim, M. R.

2017-09-01

The segmentation process is one of the most important steps in image processing and computer vision since it is vital in the initial stage of image analysis. Segmentation of medical images involves complex structures and it requires precise segmentation result which is necessary for clinical diagnosis such as the detection of tumour, oedema, and necrotic tissues. Since mammography images are grayscale, researchers are looking at the effect of colour in the segmentation process of medical images. Colour is known to play a significant role in the perception of object boundaries in non-medical colour images. Processing colour images require handling more data, hence providing a richer description of objects in the scene. Colour images contain ten percent (10%) additional edge information as compared to their grayscale counterparts. Nevertheless, edge detection in colour image is more challenging than grayscale image as colour space is considered as a vector space. In this study, we implemented red, green, yellow, and blue colour maps to grayscale mammography images with the purpose of testing the effect of colours on the segmentation of abnormality regions in the mammography images. We applied the segmentation process using the Fuzzy C-means algorithm and evaluated the percentage of average relative error of area for each colour type. The results showed that all segmentation with the colour map can be done successfully even for blurred and noisy images. Also the size of the area of the abnormality region is reduced when compare to the segmentation area without the colour map. The green colour map segmentation produced the smallest percentage of average relative error (10.009%) while yellow colour map segmentation gave the largest percentage of relative error (11.367%).

Experimental study of the X-ray spectra optimization for computed radiography mammography systems; Investigacao experimental da otimizacao do espectro de raios X em sistemas de mamografia computadorizada

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Tomal, Alessandra, E-mail: atomal@ifi.unicamp.br [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Instituto de Fisica Gleb Wataghin; Cunha, Diego M. [Universidade Federal de Uberlandia (UFU), Uberlandia, MG (Brazil). Instituto de Fisica; Nogueira, Maria S. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Gaspar, Fabio [Vigilancia Sanitaria, Campinas, SP (Brazil); Poletti, Martin E. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Departamento de Fisica

2013-12-15

Digital mammography is replacing screen-film mammography due to several advantages of digital receptors. The use of Computed Radiography (CR) mammography systems has been considered an alternative to achieve digital images with a low cost. Besides, the optimization of the X-ray spectrum, characterized by the anode/filter combination and tube potential, is an important step in order to improve the image quality with the lower dose to the breast. In this work, we investigated the optimal X-ray spectra using a figure of merit for two mammography equipment: Senographe DMR (General Electric Medical Systems) and Mammomat 3000 Nova (Siemens), both using an image plate Kodak EHR-M2 (Kodak DirectView). A PMMA phantom, simulating breast with thicknesses of 5 cm, was used. The anode/filter combinations evaluated were: Mo/Mo, Mo/Rh, Rh/Rh and Rh/Al for the Senographe system, and Mo/Mo, Mo/Rh, W/Rh for the Mammomat system, for all the intervals of tube potential range from 24 to 35 kVp. Results demonstrate that the higher values of FOM were achieved with the Rh/Rh at 29 kVp and Rh/Al at 26 kVp for the Senographe system, and for the W/Rh at 28 kVp in the Mammomat one. The reduction in the dose associated with the optimum spectra was 13 and 26% for the Senographe and Mammomat systems, respectively. Finally, our results suggest that anode/filter combinations of more energetic spectra than the standard Mo/Mo combination are recommended for thicker breast, in order to reduce the breast dose levels. (author)

Results of breast cancer screening with mammography carried out in Koriyama City over a three-year period (2001- 2003)

International Nuclear Information System (INIS)

Yoshida, Hatsuo; Iwanami, Hiroshi; Urazumi, Koujirou

2005-01-01

In 2001, biennial breast cancer screening with mammography was started in Koriyama City for women aged 40 years or over. The screening involved both physical examination, including inspection and palpation, and mammography performed separately. Women with abnormal findings on physical examination were recalled, while those without such findings underwent medio-lateral oblique projection mammography. There were a total of 15,246 responders during the three-year period 2001 -2003. The recall rate after physical examination was 3.1% and breast cancer was detected in 25 women (0.16%). For 13,310 women who underwent mammography, the recall rate was 3.9% and 25 breast cancers (0.18%) were detected. Combining these two subgroups, the overall recall rate was 6.5%, the cancer detection rate was 0.33%, the ratio of cancers detected among women who were asked to attend for a recall examination was 5.0%, and the ratio of cancers detected among women who underwent a recall examination was 5.6%. Early cancers detected at Stage 0 or 1 comprised 32 (64%), and lymph node metastasis was positive in 12 women (24%). Thus the results of our screening reached satisfactory levels in terms of the five items proposed by the Breast Imaging Reporting and Data System of the American Radiology Association. In order to further increase the quality of breast cancer screening, proper determination of categories at mammography reading and standardization of recall examination techniques, including histopathological study, are required. (author)

Image Quality and Patient Dose Optimisation in Mammography in Slovakia

International Nuclear Information System (INIS)

Horvathova, M.; Nikodemova, D.; Prikazska, M.

2003-01-01

Breast cancer represents also in Slovakia the greatest cancer risk for women, with great incidence and mortality. Conventional film-screen mammography is still the primary breast imaging modality with increasing number of mammography units and mammography examinations. From the radiation protection point of view achievement of good practice in mammography department by implementation of quality assurance play an important role for reduction of patients doses. Introduction of QA needs trained and experienced staff and requires close collaboration between radiologists, medical physicist and radiographers. At the beginning of nineties at the Institute of Preventive and Clinical Medicine we started with a survey of mean glandular doses at 15 existing mammography units in the country. On the basis of a questionnaire in the year 1991 were performed 10 488 mammography examinations, where due to out of date mammography units the mean glandular dose reached more as 3 mGy. In the following years the claim to the modern mammography units kept growing and in the year 1999 the total number of 63 mammography units were operating in Slovakia providing about 101 471 mammography examinations. According to the alarming increase of the number of mammography examinations it is absolutely necessary to work out criteria and principles for Quality Control at mammography workplaces in our country and make it obligatory for the staff of all mammography units. Summarising the CRP results it can be stated that they: 1) Initiated the suggestion of unified QA/QC criteria in mammography and the urgent need to implement them into the national program of radiology image quality improvement; 2) Remitted on unhomogenity not only in the equipment outfit but also in the procedure of evaluation of the measured parameters and imaging quality; 3) Revealed the shortcomings in the everyday practice of mammography units which can be removed only by comprehensive by training of personal in imaging radiology

Digital mammography: current state and future aspects

Energy Technology Data Exchange (ETDEWEB)

Fischer, U.; Baum, F. [Womens Health Care Center Goettingen, Diagnostisches Brustzentrum Goettingen, Goettingen (Germany); Hermann, K.P. [Georg-August-Universitaet Goettingen, Abteilung Diagnostische Radiologie, Goettingen (Germany)

2006-01-01

The introduction of digital technique in mammography has been the last step in completing the process of digitalization in diagnostic imaging. Meanwhile, some different digital techniques as well as a couple of different digital mammography systems were developed and have already been available for some years. In this review article, the relevant data of key studies are reported, the current status is defined, and perspectives of digital mammography are described. (orig.)

Mammography and breast sonography in transsexual women

International Nuclear Information System (INIS)

Weyers, S.; Villeirs, G.; Vanherreweghe, E.; Verstraelen, H.; Monstrey, S.; Van den Broecke, R.; Gerris, J.

2010-01-01

Data on the necessity of performing screening mammographies in transsexual women are lacking. The main objective of this study was to assess the possibility to perform mammography and breast sonography in transsexual women. Fifty Dutch-speaking transsexual women were interviewed about the following: attitude towards mammography and breast sonography, importance attributed to and satisfaction with breast appearance, opinion about the necessity of breast check-up, expectations regarding discomfort during the exams and knowledge about the breast surgery. A fasting blood sample, clinical breast exam, mammography and breast sonography were performed. At mammography the following parameters were noted: density, technical quality, location of the prostheses, presence of any abnormalities and painfulness. At sonography the following parameters were recorded: density, presence of cysts, visualisation of retro-areolar ducts or any abnormalities. Twenty-three percent of patients are not aware of the type of breast implants and 79% do not know their position to the pectoral muscles. Patient satisfaction with the appearance of their breasts was rather high (7.94 on a scale of 0-10). Mean expected and experienced pain from mammography was low (4.37 and 2.00 respectively). There was no statistically significant difference in expected pain between those who already had mammography and those who did not. There was a significant positive correlation between the expected and the experienced pain. Mammography and breast sonography were technically feasible and no gross anomalies were detected. Since both exams were judged as nearly painless, 98% of transsexual women intended to come back if they would be invited. Since breast cancer risk in transsexual women is largely unknown and breast exams are very well accepted, breast screening habits in this population should not differ from those of biological women.

Mammography and breast sonography in transsexual women

Energy Technology Data Exchange (ETDEWEB)

Weyers, S., E-mail: steven.weyers@ugent.b [Department of Gynecology, Ghent University Hospital, De Pintelaan 185, B-9000 Ghent (Belgium); Villeirs, G.; Vanherreweghe, E. [Department of Radiology, Ghent University Hospital, Ghent (Belgium); Verstraelen, H. [Department of Gynecology, Ghent University Hospital, De Pintelaan 185, B-9000 Ghent (Belgium); Monstrey, S. [Department of Plastic Surgery, Ghent University Hospital, Ghent (Belgium); Van den Broecke, R.; Gerris, J. [Department of Gynecology, Ghent University Hospital, De Pintelaan 185, B-9000 Ghent (Belgium)

2010-06-15

Data on the necessity of performing screening mammographies in transsexual women are lacking. The main objective of this study was to assess the possibility to perform mammography and breast sonography in transsexual women. Fifty Dutch-speaking transsexual women were interviewed about the following: attitude towards mammography and breast sonography, importance attributed to and satisfaction with breast appearance, opinion about the necessity of breast check-up, expectations regarding discomfort during the exams and knowledge about the breast surgery. A fasting blood sample, clinical breast exam, mammography and breast sonography were performed. At mammography the following parameters were noted: density, technical quality, location of the prostheses, presence of any abnormalities and painfulness. At sonography the following parameters were recorded: density, presence of cysts, visualisation of retro-areolar ducts or any abnormalities. Twenty-three percent of patients are not aware of the type of breast implants and 79% do not know their position to the pectoral muscles. Patient satisfaction with the appearance of their breasts was rather high (7.94 on a scale of 0-10). Mean expected and experienced pain from mammography was low (4.37 and 2.00 respectively). There was no statistically significant difference in expected pain between those who already had mammography and those who did not. There was a significant positive correlation between the expected and the experienced pain. Mammography and breast sonography were technically feasible and no gross anomalies were detected. Since both exams were judged as nearly painless, 98% of transsexual women intended to come back if they would be invited. Since breast cancer risk in transsexual women is largely unknown and breast exams are very well accepted, breast screening habits in this population should not differ from those of biological women.

Computer-aided detection of breast carcinoma in standard mammographic projections with digital mammography

Energy Technology Data Exchange (ETDEWEB)

Destounis, Stamatia [Elizabeth Wende Breast Care, LLC, Rochester, NY (United States); University of Rochester, School of Medicine and Dentistry, Rochester, NY (United States); Hanson, Sarah; Morgan, Renee; Murphy, Philip; Somerville, Patricia; Seifert, Posy; Andolina, Valerie; Arieno, Andrea; Skolny, Melissa; Logan-Young, Wende [Elizabeth Wende Breast Care, LLC, Rochester, NY (United States)

2009-06-15

A retrospective evaluation of the ability of computer-aided detection (CAD) ability to identify breast carcinoma in standard mammographic projections. Forty-five biopsy proven lesions in 44 patients imaged digitally with CAD applied at examination were reviewed. Forty-four screening BIRADS {sup registered} category 1 digital mammography examinations were randomly identified to serve as a comparative normal/control population. Data included patient age; BIRADS {sup registered} breast density; lesion type, size, and visibility; number, type, and location of CAD marks per image; CAD ability to mark lesions; needle core and surgical pathologic correlation. The CAD lesion/case sensitivity of 87% (n=39), image sensitivity of 69% (n=31) for mediolateral oblique view and 78% (n=35) for the craniocaudal view was found. The average false positive rate in 44 normal screening cases was 2.0 (range 1-8). The 2.0 figure is based on 88 reported false positive CAD marks in 44 normal screening exams: 98% (n=44) lesions proceeded to excision; initial pathology upgraded at surgical excision from in situ to invasive disease in 24% (n=9) lesions. CAD demonstrated potential to detect mammographically visible cancers in standard projections for all lesion types. (orig.)

Evaluation of breast symptoms with mammography and ultrasonography

Directory of Open Access Journals (Sweden)

Emine Devolli Disha

2011-12-01

Full Text Available Introduction: Aim of the study was to discern which are more frequent symptoms presented in malign and benign masses diagnosed by mammography and ultrasonography.Methods: Our study group consisted of 546 female patients, with breast symptoms such as palpable lumps (40.8%, pain in the breast (26%, localized lumpiness or nodularity (13.7%, nipple retraction (11.2%, nipplebloody discharge (5.1% and redness and swelling of the breast (3.1%. All 546 patients were examined by ultrasonography and mammography. Biopsy was performed according to the findings of mammography and ultrasonography.Results: In breast cancer detection ultrasonography showed an efficiency of 79.4% compared to 55.0% for mammography in detecting breast lump, in the case of nipple retraction mammography showed an efficiency of 89.1% compared to 80.4% for ultrasound, while the lowest efficiency for mammography was in the cases with localized lumpiness or nodularity 17.1% compared to 45.7% for ultrasound. In detecting fibrocystic changes where the most common symptoms was pain, ultrasonography showed an efficiency of 99.3 % compared to 84.2 % for mammography.Conclusions: Our study confirmed that breast lumps are detectable in the majority of patients with breast cancer. The most frequent symptoms in patient with benign lesions were pain or localized discomfort. The diagnostic accuracy for carcinomas of the breast and for benign lesions according to symptoms was higher for ultrasound than for mammography.

Computers and Reading: 1984-1989. Selections from "Micro Missive," the Newsletter of MicroSIG, The Special Interest Group for Microcomputers in Reading of the International Reading Association.

Science.gov (United States)

Balajthy, Ernest

This publication is a collection of eight articles and ten software reviews written by the author for "Micro Missive" since 1984. "Micro Missive" is a quarterly newsletter that has regularly informed International Reading Association members of new developments in computer-based instruction and reading/language arts through articles, software…

Computer Vision Syndrome for Non-Native Speaking Students: What Are the Problems with Online Reading?

Science.gov (United States)

Tseng, Min-chen

2014-01-01

This study investigated the online reading performances and the level of visual fatigue from the perspectives of non-native speaking students (NNSs). Reading on a computer screen is more visually more demanding than reading printed text. Online reading requires frequent saccadic eye movements and imposes continuous focusing and alignment demand.…

FROST: an ASIC for digital mammography with synchrotron radiation

International Nuclear Information System (INIS)

Bergamaschi, A.; Prest, M.; Vallazza, E.; Arfelli, F.; Dreossi, D.; Longo, R.; Olivo, A.; Pani, S.; Castelli, E.

2003-01-01

The FRONTier RADiography (FRONTRAD) collaboration is developing a digital system for mammography at the Elettra Synchrotron Light Source in Trieste. The system is based on a silicon microstrip detector array. The ASIC FROST (FRONTRAD Read Out sySTem) was developed as a collaboration between INFN Trieste and Aurelia Microelettronica and is designed to operate in single photon counting mode. FROST provides low-noise and high-gain performances and is able to work at incident photon rates higher than 100 kHz with almost 100% efficiency. The ASIC has been tested and the first images of mammographic test objects will be shown. The acquisition time per breast image should be of about 10 s

Perceived Convenience, Compatibility, and Media Richness Contribute Significantly toDedicated E-book Reader Acceptance. A Review of: Lai, J.-Y., & Chang, C.-Y. (2011. User attitudes toward dedicated e-book readers for reading: The effects of convenience, compatibility and media richness. Online Information Review, 35(4, 558-580.

Directory of Open Access Journals (Sweden)

Theresa S. Arndt

2012-06-01

Full Text Available Objective – Investigates the effects ofperceived convenience, compatibility andmedia richness on users’ attitudes towarddedicated e-book readers.Design – Convenience sample survey.Setting – Taiwanese university.Subjects – A total of 288 students at the seniorsecondary (5%, four-year university (78%,and graduate student (17% levels. Malefemaleparticipation was approximately equal.Methods – Students completed a 23-itemsurvey on dedicated e-book readers, withquestions on perceived usefulness, perceivedease of use, intention to use, convenience,compatibility, and media richness. Data wasanalyzed using the partial least squaresstatistical technique.Main Results – Users state an increasedintention to use dedicated e-book readers ifthey perceive the technology to be compatiblewith what they desire in a “book,” if the devicedelivers rich media content, and if the device isconvenient. Compatibility was found tosignificantly affect perceived ease of use, andwas found to be the strongest influence onintent to use a dedicated e-book reader.Compatibility, media richness andconvenience also increased the perceivedusefulness of dedicated e-book readers.Conclusion – Users will prefer dedicated e-book readers that are compatible with their preferences in a “book,” that deliver media-rich content, and that they find convenient. The study has implications for the design and development of e-book reading devices.

Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer

International Nuclear Information System (INIS)

Kitahama, Hiroyuki

1991-01-01

The aim of this study is to present efficacy of storage phosphor-based digital mammography (CR-mammography) in diagnosis of breast cancer. Ninety-seven cases with breast cancer including 44 cases less than 2 cm in macroscopic size (t1 cases) were evaluated using storage phosphor-based digital mammography (2000 x 2510 pixels by 10 bits). Abnormal findings on CR-mammography were detected in 86 cases (88.7%) of 97 women with breast cancer. Sensitivity of CR-mammography was 88.7%. It was superior to that of film-screen mammography. On t1 breast cancer cases, sensitivity on CR-mammography was 88.6%. False negative rate in t1 breast cancer cases was reduced by image processing using CR-mammography. To evaluate microcalcifications, CR-mammograms and film-screen mammograms were investigated in 22 cases of breast cancer proven pathologically the existence of microcalcifications and 11 paraffin tissue blocks of breast cancer. CR-mammography was superior to film-screen mammography in recognizing of microcalcifications. As regards the detectability for the number and the shape of microcalcifications, CR-mammography was equivalent to film-screen mammography. Receiver operating characteristic (ROC) analysis by eight observers was performed for CR-mammography and film-screen mammography with 54 breast cancer patients and 54 normal cases. The detectability of abnormal findings of breast cancer on CR-mammography (ROC area=0.91) was better than that on film-screen mammography (ROC area=0.88) (p<0.05). Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer was discussed and demonstrated in this study. (author)

Contrast-enhanced spectral mammography: comparison with conventional mammography and histopathology in 152 women.

Science.gov (United States)

Luczyńska, Elzbieta; Heinze-Paluchowska, Sylwia; Dyczek, Sonia; Blecharz, Pawel; Rys, Janusz; Reinfuss, Marian

2014-01-01

The goal of the study was to compare conventional mammography (MG) and contrast-enhanced spectral mammography (CESM) in preoperative women. The study was approved by the local Ethics Committee and all participants provided informed consent. The study included 152 consecutive patients with 173 breast lesions diagnosed on MG or CESM. All MG examinations and consults were conducted in one oncology centre. Non-ionic contrast agent, at a total dose of 1.5 mL/kg body weight, was injected intravenous. Subsequently, CESM exams were performed with a mammography device, allowing dual-energy acquisitions. The entire procedure was done within the oncology centre. Images from low and high energy exposures were processed together and the combination provided an "iodine" image which outlined contrast up-take in the breast. MG detected 157 lesions in 150 patients, including 92 infiltrating cancers, 12 non-infiltrating cancers, and 53 benign lesions. CESM detected 149 lesions in 128 patients, including 101 infiltrating cancers, 13 non-infiltrating cancers, and 35 benign lesions. CESM sensitivity was 100% (vs. 91% for MG), specificity was 41% (vs. 15% for MG), area under the receiver operating characteristic curve was 0.86 (vs. 0.67 for MG), and accuracy was 80% (vs. 65% for MG) for the diagnosis of breast cancer. Both MG and CESM overestimated lesion sizes compared to histopathology (p mammography.

Valuation of a CD-96 reader dedicated to quick read-out and archivisation of foil dosemeter absorbance; Ocena czytnika CD-96 przeznaczonego do szybkiego mierzenia absorbancji tasmowych dozymetrow foliowych i archiwizowania wynikow pomiaru

Energy Technology Data Exchange (ETDEWEB)

Malicki, W.; Bryl-Sandelewska, T.; Stuglik, Z.

1997-12-31

A check of the useful parameters of CD-96 reader is presented. The reader was constructed in the Department of Radioisotope Instruments and Methods of the INCT and dedicated to quick read-out of the foil dosemeter absorbances and for their archivisation. (author). 9 refs, 9 figs.

Teaching atlas of mammography

International Nuclear Information System (INIS)

Tabar, L.; Dean, P.B.

1985-01-01

The illustrated case reports in this teaching atlas cover practically the entire range of possible pathological changes and are based on in-patient case material and 80,000 screening documents. The two basic approaches, - detection and analysis of changes -, are taught comprehensively and in great detail. A systematic procedure for analysing the mammographies, in order to detect even the very least changes, and its practical application is explained using mammographies showing unclear findings at first sight. A system of coordinates is presented which allows precise localisation of the changes. Exercises for practising the technique of identifying the pathological changes round up the methodolical chapters. Additional imaging technical enhancements and detail enlargements are of great help in interpreting the findings. The specific approach adopted for this teaching atlas is a 'reverse procedure', which leaves the beaten track and starts with analysing the mammographies and evaluating the radiographic findings, in order to finally derive the diagnosis. (orig./CB) [de

Mammography in women under 35

International Nuclear Information System (INIS)

Panzarola, P.; Bellucci, M.C.

1991-01-01

The detection of breast cancer in women under 35 is quite an uncommon event, accounting only for 3.2-3.4% of all breast cancers. To determine the indications for mammography in women under 35, the authors correlated clinical, mammographic, and US findings with fine-needle aspiration/surgical biopsy and follow-up results in 1040 symptomatic women examined at the Center of Senology of the Istitute of Radiology - University of Perugia, Italy, from 1984 to June 1990. Of 1040 women, 482 (41.6%) had normal findings; benign disease was diagnosed in 558 (53.7%) cases, and malignant disease in 49 (4.7%). Mammography was very useful to diagnose malignancy in palpable breast lesions, as well as to suggest the need for biopsy, to detect metachronous cancer and to define lesion sizes. In inflammatory process - e.g., mastitis and abscesses - both mammography and US were capable as its remission after therapy. Galactography had a specific role in the evaluation of the mammary duct and demonstrated intraductal pathologic conditions. In the authors'experiences, mammography never showed occult breast cancers in women with no palpable breast lesions or hematic nipple discharge

FDA & digital mammography: why has FDA required full field digital mammography systems to be regulated as potentially dangerous devices for more than 10 years?

Science.gov (United States)

Nields, Morgan W

2010-05-01

Digital mammography is routinely used in the US to screen asymptomatic women for breast cancer and currently over 50% of US screening centers employ the technology. In spite of FDAs knowledge that digital mammography requires less radiation than film mammography and that its equivalence has been proven in a prospective randomized trial, the agency has failed to allow the technology market access via the 510(k) pre market clearance pathway. As a result of the restrictive Pre Market Approval process, only four suppliers have received FDA approval. The resulting lack of a competitive market has kept costs high, restricted technological innovation, and impeded product improvements as a result of PMA requirements. Meanwhile, at least twelve companies are on the market in the EU and the resulting competitive market has lowered costs and provided increased technological choice. A cultural change with new leadership occurred in the early 90's at FDA. The historical culture at the Center for Devices and Radiological Health of collaboration and education gave way to one characterized by a lack of reliance on outside scientific expertise, tolerance of decision making by unqualified reviewers, and an emphasis on enforcement and punishment. Digital mammography fell victim to this cultural change and as a result major innovations like breast CT and computer aided detection technologies are also withheld from the market. The medical device law, currently under review by the Institute of Medicine, should be amended by the Congress so that new technologies can be appropriately classified in accordance with the risk based assessment classification system detailed in Chapter V of the Federal Food, Drug, and Cosmetic Act. A panel of scientific experts chartered by the NIH or IOM should determine the classification appropriate for new technologies that have no historical regulatory framework. This would be binding on FDA. Unless the law is changed we will likely again experience

Contrast-Enhanced Spectral Mammography: Comparison with Conventional Mammography and Histopathology in 152 Women

OpenAIRE

Luczyńska, Elzbieta; Heinze-Paluchowska, Sylwia; Dyczek, Sonia; Blecharz, Pawel; Rys, Janusz; Reinfuss, Marian

2014-01-01

Objective The goal of the study was to compare conventional mammography (MG) and contrast-enhanced spectral mammography (CESM) in preoperative women. Materials and Methods The study was approved by the local Ethics Committee and all participants provided informed consent. The study included 152 consecutive patients with 173 breast lesions diagnosed on MG or CESM. All MG examinations and consults were conducted in one oncology centre. Non-ionic contrast agent, at a total dose of 1.5 mL/kg body...

Towards Effective Non-Invasive Brain-Computer Interfaces Dedicated to Gait Rehabilitation Systems

Directory of Open Access Journals (Sweden)

Thierry Castermans

2013-12-01

Full Text Available In the last few years, significant progress has been made in the field of walk rehabilitation. Motor cortex signals in bipedal monkeys have been interpreted to predict walk kinematics. Epidural electrical stimulation in rats and in one young paraplegic has been realized to partially restore motor control after spinal cord injury. However, these experimental trials are far from being applicable to all patients suffering from motor impairments. Therefore, it is thought that more simple rehabilitation systems are desirable in the meanwhile. The goal of this review is to describe and summarize the progress made in the development of non-invasive brain-computer interfaces dedicated to motor rehabilitation systems. In the first part, the main principles of human locomotion control are presented. The paper then focuses on the mechanisms of supra-spinal centers active during gait, including results from electroencephalography, functional brain imaging technologies [near-infrared spectroscopy (NIRS, functional magnetic resonance imaging (fMRI, positron-emission tomography (PET, single-photon emission-computed tomography (SPECT] and invasive studies. The first brain-computer interface (BCI applications to gait rehabilitation are then presented, with a discussion about the different strategies developed in the field. The challenges to raise for future systems are identified and discussed. Finally, we present some proposals to address these challenges, in order to contribute to the improvement of BCI for gait rehabilitation.

Power spectrum analysis of the x-ray scatter signal in mammography and breast tomosynthesis projections.

Science.gov (United States)

Sechopoulos, Ioannis; Bliznakova, Kristina; Fei, Baowei

2013-10-01

To analyze the frequency domain characteristics of the signal in mammography images and breast tomosynthesis projections with patient tissue texture due to detected scattered x-rays. Acquisitions of x-ray projection images of 19 different patient breasts were simulated using previously acquired volumetric patient images. Acquisition of these images was performed with a dedicated breast CT prototype system, and the images were classified into voxels representing skin, adipose, and glandular tissue with a previously validated automated algorithm. The classified three dimensional images then underwent simulated mechanical compression representing that which is performed during acquisition of mammography and breast tomosynthesis images. The acquisition of projection images of each patient breast was simulated using Monte Carlo methods with each simulation resulting in two images: one of the primary (non-scattered) signal and one of the scatter signal. To analyze the scatter signal for both mammography and breast tomosynthesis, two projections images of each patient breast were simulated, one with the x-ray source positioned at 0° (mammography and central tomosynthesis projection) and at 30° (wide tomosynthesis projection). The noise power spectra (NPS) for both the scatter signal alone and the total signal (primary + scatter) for all images were obtained and the combined results of all patients analyzed. The total NPS was fit to the expected power-law relationship NPS(f) = k/f β and the results were compared with those previously published on the power spectrum characteristics of mammographic texture. The scatter signal alone was analyzed qualitatively and a power-law fit was also performed. The mammography and tomosynthesis projections of three patient breasts were too small to analyze, so a total of 16 patient breasts were analyzed. The values of β for the total signal of the 0° projections agreed well with previously published results. As expected, the scatter

Digital mammography in breast cancer screening: Evaluation and innovation

NARCIS (Netherlands)

Bluekens, A.M.J.

2015-01-01

With all other imaging modalities in radiology being digitised and conventional mammography being ready to phase out the transition to digital mammography was inevitable. This thesis describes the performance of digital screening mammography and the consequences of implementation in a

CONTRAST ENHANCED SPECTRAL MAMMOGRAPHY (CESM (REVIEW

Directory of Open Access Journals (Sweden)

N. I. Rozhkova

2015-01-01

Full Text Available The problem of early diagnosis of a breast cancer is extremely actual. Growth of incidence at women from 19 to 39 years increased for 34% over the last 10 years. It defines need of acceleration of development and deployment of the latest technologies of identification of the earliest symptoms of diseases. The x-ray mammography is the conducting method among of all radiological methods of diagnostics. Nevertheless a number of restrictions of method reduces its efficiency. The technologies increasing informational content of x-ray mammography – the leading method of screening – due to use of artificial contrasting and advantages of digital technologies are constantly developed. In this review it is described works, in which the authors having clinical experience of application of CESM – contrastenhanced spectral mammography on representative group of women. Positive sides and restrictions of new technology in comparison with mammography, ultrasonography and MRT are shown in this article.

Heavy-ion mammography and breast cancer

International Nuclear Information System (INIS)

Fabrikant, J.I.; Tobias, C.A.; Capp, M.P.; Holley, W.R.; Woodruff, K.H.; Sickles, E.A.

1980-01-01

Heavy-ion radiography is a new diagnostic imaging technique developed in our laboratory that produces superior density resolution at low radiation doses. Heavy-ion mammography has now emerged as a low-dose, safe, reliable, noninvasive diagnostic radiological procedure that can quantitate and image very small differences in soft tissue densities in the breast tissues of patients with clinical breast disease. The improved density resolution of heavy-ion mammography over conventional X-ray mammography and breast xerography provides the potential of detecting small breast cancers of less than 1 cm diameter. The radiation dose to the breast from carbon-ion mammorgraphy is about 50 mrad or less, and can potentially be only a fraction of this level. The results of the present clinical trial in progress of heavy-ion mammography in 37 patients, thus far studied, are extremely encouraging, and warrant continued study for application to the early diagnosis of breast cancer in women

Computer-aided detection of breast carcinoma in standard mammographic projections with digital mammography

International Nuclear Information System (INIS)

Destounis, S.; Hanson, S.

2007-01-01

This study was conducted to retrospectively evaluate a computer-aided detection system's ability to detect breast carcinoma in multiple standard mammographic projections. Forty-five lesions in 44 patients imaged with digital mammography (Selenia registered , Hologic, Bedford, MA; Senographe registered , GE, Milwaukee, WI) and had computer-aided detection (CAD, Image-checker registered V 8.3.15, Hologic/R2, Santa Clara, CA) applied at the time of examination were identified for review; all were subsequently recommended to biopsy where cancer was revealed. These lesions were determined by the study Radiologist to be visible in both standard mammographic images (mediolateral oblique, MLO; craniocaudal, CC). For each patient, case data included patient age, tissue density, lesion type, BIRADS registered assessment, lesion size, lesion visibility-visible on MLO and/or CC view, ability of CAD to correctly mark the cancerous lesion, number of CAD marks per image, needle core biopsy results and surgical pathologic correlation. For this study cohort. CAD lesion/case sensitivity of 87% (n = 39) was found and image sensitivity was found to be 69% (n = 31) for MLO view and 78% (n = 35) for the CC view. For the study cohort, cases presented with a median of four marks per cases (range 0-13). Eighty-four percent (n = 38) of lesions proceeded to excision; initial needle biopsy pathology was upgraded at surgical excision from in situ disease to invasive for 24% (n = 9) lesions. CAD has demonstrated the potential to detect mammographically visible cancers in multiple standard mammographic projections in all categories of lesions in this study cohort. (orig.)

Image quality of digital mammography images produced using wet and dry laser imaging systems

International Nuclear Information System (INIS)

Al Khalifah, K.; Brindhaban, A.; AlArfaj, R.; Jassim, O.

2006-01-01

Introduction: A study was carried out to compare the quality of digital mammographic images printed or processed by a wet laser imaging system and a dedicated mammographic dry laser imaging system. Material and methods: Digital images of a tissue equivalent breast phantom were obtained using a GE Senographe 2000D digital mammography system and different target/filter combinations of the X-ray tube. These images were printed on films using the Fuji FL-IM D wet laser imaging system and the Kodak DryView 8600 dry laser imaging system. The quality of images was assessed in terms of detectability of microcalcifications and simulated tumour masses by five radiologists. In addition, the contrast index and speed index of the two systems were measured using the step wedge in the phantom. The unpaired, unequal variance t-test was used to test any statistically significant differences. Results: There were no significant (p < 0.05) differences between the images printed using the two systems in terms of microcalcification and tumour mass detectability. The wet system resulted in slightly higher contrast index while the dry system showed significantly higher speed index. Conclusion: Both wet and dry laser imaging systems can produce mammography images of good quality on which 0.2 mm microcalcifications and 2 mm tumour masses can be detected. Dry systems are preferable due to the absence of wet chemical processing and solid or liquid chemical waste. The wet laser imaging systems, however, still represent a useful alternative to dry laser imaging systems for mammography studies

Pain and discomfort during mammography

DEFF Research Database (Denmark)

Aro, A R; Absetz-Ylöstalo, P; Eerola, T

1996-01-01

was the most powerful factor explaining pain and discomfort among women with earlier mammography. However, it had no effect among women without earlier mammography, for whom screening-related nervousness and perceptions of staff were crucial. Suggested interventions include better information before screening......The aim of this prospective study was to investigate associations of mammography pain and discomfort with sociodemographics, personal history and psychological and situational factors. Subjects were women with a negative screening finding (n = 883) from a random sample of 50-year-old Finnish women...... attending their first breast cancer screening. Questionnaires were sent 1 month before the screening invitation and 2 months after screening. Sixty-one per cent reported painful and 59% uncomfortable mammograms (4% severely). Linear regression analyses showed that anticipation of pain and discomfort...

Mammography quality assurance in Morocco

International Nuclear Information System (INIS)

Zaoui, F.; Talsmat, K.; Lalaoui, K.

2001-01-01

The 'Centre National de l'Energie, des Sciences et des Techniques Nucleaires' (CNESTEN) realised, from February 1999 to March 2000, a quality control of 41 mammography facilities in Morocco. The protocol and standards adopted for achieving the control of elements constituting the mammography chain are those elaborated by GIM and Qualix association. Statistics and conformities results are presented. The program was performed in order to demonstrate to the practitioners in mammography field, the utility and necessity to have a national quality assurance policy. The main objective of CNESTEN is to be accredited by the Moroccan government as a reference laboratory in quality control and dose evaluation in medical imaging and radiotherapy. To achieve this goal the CNESTEN has set up Medical Physic Unit well trained and equipped with the necessary instruments. (author)

Breast cancer screening using tomosynthesis in combination with digital mammography.

Science.gov (United States)

Friedewald, Sarah M; Rafferty, Elizabeth A; Rose, Stephen L; Durand, Melissa A; Plecha, Donna M; Greenberg, Julianne S; Hayes, Mary K; Copit, Debra S; Carlson, Kara L; Cink, Thomas M; Barke, Lora D; Greer, Linda N; Miller, Dave P; Conant, Emily F

2014-06-25

Mammography plays a key role in early breast cancer detection. Single-institution studies have shown that adding tomosynthesis to mammography increases cancer detection and reduces false-positive results. To determine if mammography combined with tomosynthesis is associated with better performance of breast screening programs in the United States. Retrospective analysis of screening performance metrics from 13 academic and nonacademic breast centers using mixed models adjusting for site as a random effect. Period 1: digital mammography screening examinations 1 year before tomosynthesis implementation (start dates ranged from March 2010 to October 2011 through the date of tomosynthesis implementation); period 2: digital mammography plus tomosynthesis examinations from initiation of tomosynthesis screening (March 2011 to October 2012) through December 31, 2012. Recall rate for additional imaging, cancer detection rate, and positive predictive values for recall and for biopsy. A total of 454,850 examinations (n=281,187 digital mammography; n=173,663 digital mammography + tomosynthesis) were evaluated. With digital mammography, 29,726 patients were recalled and 5056 biopsies resulted in cancer diagnosis in 1207 patients (n=815 invasive; n=392 in situ). With digital mammography + tomosynthesis, 15,541 patients were recalled and 3285 biopsies resulted in cancer diagnosis in 950 patients (n=707 invasive; n=243 in situ). Model-adjusted rates per 1000 screens were as follows: for recall rate, 107 (95% CI, 89-124) with digital mammography vs 91 (95% CI, 73-108) with digital mammography + tomosynthesis; difference, -16 (95% CI, -18 to -14; P tomosynthesis; difference, 1.3 (95% CI, 0.4-2.1; P = .004); for cancer detection, 4.2 (95% CI, 3.8-4.7) with digital mammography vs 5.4 (95% CI, 4.9-6.0) with digital mammography + tomosynthesis; difference, 1.2 (95% CI, 0.8-1.6; P tomosynthesis; difference, 1.2 (95% CI, 0.8-1.6; P tomosynthesis was associated with an increase

Contrast-enhanced spectral mammography vs. mammography and MRI - clinical performance in a multi-reader evaluation.

Science.gov (United States)

Fallenberg, Eva M; Schmitzberger, Florian F; Amer, Heba; Ingold-Heppner, Barbara; Balleyguier, Corinne; Diekmann, Felix; Engelken, Florian; Mann, Ritse M; Renz, Diane M; Bick, Ulrich; Hamm, Bernd; Dromain, Clarisse

2017-07-01

To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) to digital mammography (MG) and magnetic resonance imaging (MRI) in a prospective two-centre, multi-reader study. One hundred seventy-eight women (mean age 53 years) with invasive breast cancer and/or DCIS were included after ethics board approval. MG, CESM and CESM + MG were evaluated by three blinded radiologists based on amended ACR BI-RADS criteria. MRI was assessed by another group of three readers. Receiver-operating characteristic (ROC) curves were compared. Size measurements for the 70 lesions detected by all readers in each modality were correlated with pathology. Reading results for 604 lesions were available (273 malignant, 4 high-risk, 327 benign). The area under the ROC curve was significantly larger for CESM alone (0.84) and CESM + MG (0.83) compared to MG (0.76) (largest advantage in dense breasts) while it was not significantly different from MRI (0.85). Pearson correlation coefficients for size comparison were 0.61 for MG, 0.69 for CESM, 0.70 for CESM + MG and 0.79 for MRI. This study showed that CESM, alone and in combination with MG, is as accurate as MRI but is superior to MG for lesion detection. Patients with dense breasts benefitted most from CESM with the smallest additional dose compared to MG. • CESM has comparable diagnostic performance (ROC-AUC) to MRI for breast cancer diagnostics. • CESM in combination with MG does not improve diagnostic performance. • CESM has lower sensitivity but higher specificity than MRI. • Sensitivity differences are more pronounced in dense and not significant in non-dense breasts. • CESM and MRI are significantly superior to MG, particularly in dense breasts.

Radiogenic breast cancer risk and mammography

International Nuclear Information System (INIS)

Jayaprakash, Shobha; Nair, C.P.R.; Rao, B.S.; Sawant, S.G.

2001-01-01

There is a general concern that the risks from mammography screening in inducting radiogenic breast cancer may outweigh the possible benefits to be derived from it. A review of epidemiological, case-control and cohort studies of radiogenic breast cancer, age-specific incidence and dose and dose-rate relationship reveals that such a fear is unfounded. The dose to the breast tissues in a quality assured mammography screening programme falls far below the levels that were observed to produce increased relative risk. The age-specific incidence rates also indicate that the need for mammography is for the women of age at which the relative risk is minimum

Computer assisted analysis of research-based teaching method in English newspaper reading teaching

Science.gov (United States)

Jie, Zheng

2017-06-01

In recent years, the teaching of English newspaper reading has been developing rapidly. However, the teaching effect of the existing course is not ideal. The paper tries to apply the research-based teaching model to English newspaper reading teaching, investigates the current situation in higher vocational colleges, and analyzes the problems. It designs a teaching model of English newspaper reading and carries out the empirical research conducted by computers. The results show that the teaching mode can use knowledge and ability to stimulate learners interest and comprehensively improve their ability to read newspapers.

Introduction of computed radiography in two mammography services: image quality and dose analysis

International Nuclear Information System (INIS)

Jakubiak, Rosangela R.; Gamba, Humberto R.; Ramos, Maria M.; Faversani, Gislene G.; Peixoto, Joao E.

2008-01-01

This study has evaluated the impact of the introduction of CR technology in the routine of two mammography services operating with Lorad Affinity X-ray units and CR Fuji Profect One system. Mean glandular dose was determined to set Automatic Exposure Control parameters according to optimal image quality. Reject analysis of patient images was made to establish the overall impact in routine work. As regards to dose evaluation, the results show that in 44% of mammography exams the MGD were above action levels. It is due to inadequate AEC adjustment and insufficient training of the staff in operating CR systems. In addition, common errors with screen/film systems like wrong breast positing and selection of exposure parameters, as well as X-ray unit failures like insufficient anti scatter grid movement still occurs. This is an indication that ongoing efforts should be concentrated in the constancy of AEC adjustment for CR image plates and staff training. Until now, brazilian health authorities did not implement any program to evaluate digital systems performance, but efforts are being done in order to provide guidelines to breast screening aiming the control of breast dose compatible with optimal image quality. (author)

Dose to population as a metric in the design of optimised exposure control in digital mammography

International Nuclear Information System (INIS)

Klausz, R.; Shramchenko, N.

2005-01-01

This paper describes a methods for automatic optimisation of parameter (AOP) in digital mammography systems. Using a model of the image chain, contrast to noise ratio (CNR) and average glandular dose (AGD) are computed for possible X-ray parameters and breast types. The optimisation process consists of the determination of the operating points providing the lowest possible AGD for each CNR level and breast type. The proposed metric for the dose used in the design of an AOP mode is the resulting dose to the population, computed by averaging the AGD values over the distribution of breast types in the population. This method has been applied to the automatic exposure control of new digital mammography equipment. Breast thickness and composition are estimated from a low dose pre-exposure and used to index tables containing sets of optimised operating points. The resulting average dose to the population ranges from a level comparable to state-of-the-art screen/film mammography to a reduction by a factor of two. Using this method, both CNR and dose are kept under control for all breast types, taking into consideration both individual and collective risk. (authors)

Computers and Instruction: Implications of the Rising Tide of Criticism for Reading Education.

Science.gov (United States)

Balajthy, Ernest

1988-01-01

Examines two major reasons that schools have adopted computers without careful prior examination and planning. Surveys a variety of criticisms targeted toward some aspects of computer-based instruction in reading in an effort to direct attention to the beneficial implications of computers in the classroom. (MS)

A study of some technical essentials of X-ray mammography

International Nuclear Information System (INIS)

Cao Houde; Jiang Qin

2000-01-01

Objective: To improve the quality of mammography and diagnostic accuracy by analyzing and studying some of the technical essentials of X-ray mammography. Methods: The mammography quality of 21 hospitals were investigated. The image quality of normal intensifying screen-film combination was tested and compared with computerized mammography. The filming positions and operating skills were studied. Results: The important mammography details that were displayed have low conformity with the diagnostic requirements, mainly due to non-conformity of these equipment to the requirements. The optimal pressure suitable for mammography of the Chinese women was around 12 kg. Conclusion: Necessary attention must be paid to the improvement of imaging features of these equipment. The improved operating skills will greatly raise the detecting percentage of pathological changes of breasts

Second-Grade Urban Learners: Preliminary Findings for a Computer-Assisted, Culturally Relevant, Repeated Reading Intervention

Science.gov (United States)

Bennett, Jessica G.; Gardner, Ralph, III; Cartledge, Gwendolyn; Ramnath, Rajiv; Council, Morris R., III

2017-01-01

This study investigated the effects of a multicomponent, supplemental intervention on the reading fluency of second-grade African-American urban students who showed reading and special education risk. The packaged intervention combined repeated readings and culturally relevant stories, delivered through a novel computer software program to enhance…

A Computational and Empirical Investigation of Graphemes in Reading

Science.gov (United States)

Perry, Conrad; Ziegler, Johannes C.; Zorzi, Marco

2013-01-01

It is often assumed that graphemes are a crucial level of orthographic representation above letters. Current connectionist models of reading, however, do not address how the mapping from letters to graphemes is learned. One major challenge for computational modeling is therefore developing a model that learns this mapping and can assign the…

Average glandular dose in routine mammography screening using a Sectra Microdose Mammography unit

International Nuclear Information System (INIS)

Hemdal, B.; Herrnsdorf, L.; Andersson, I.; Bengtsson, G.; Heddson, B.; Olsson, M.

2005-01-01

The Sectra MicroDose Mammography system is based on direct photon counting (with a solid-state detector), and a substantially lower dose to the breast than when using conventional system can be expected. In this work absorbed dose measurements have been performed for the first unit used in routine mammography screening (at the Hospitals of Helsingborg (Sweden)). Two European protocols on dosimetry in mammography have been followed. Measurement of half value layer (HVL) cannot be performed as prescribed, but this study has demonstrated than non-invasive measurements of HVL can be performed accurately with a sensitive and well collimated solid-state detector with simultaneous correction for the energy dependence. The average glandular dose for a 50 mm standard breast with 50% glandularity, simulated by 45 mm polymethylmethacrylate, was found to be 0.21 and 0.28 mGy in March and December 2004, respectively. These values are much lower than for any other mammography system on the market today. It has to be stressed that the measurement were made using the current clinical settings and that no systematic optimisation of the relationship between absorbed dose and diagnostic image quality has been performed within the present study. In order to further increase the accuracy of absorbed dose measurements for this unit, the existing dose protocols should be revised to account also for the tungsten/aluminium anode/filter combination, the multi-slit pre-collimator device and the occurrence of a dose profile in the scanning direction. (authors)

Contrast-Enhanced Spectral Mammography: Comparison with Conventional Mammography and Histopathology in 152 Women

Energy Technology Data Exchange (ETDEWEB)

Luczyńska, Elzbieta; Heinze-Paluchowska, Sylwia; Dyczek, Sonia [Department of Radiology, Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, Krakow 31-115 (Poland); Blecharz, Pawel [Department of Gynecologic Oncology, Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, Krakow 31-115 (Poland); Rys, Janusz [Department of Tumour Pathology, Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, Krakow 31-115 (Poland); Reinfuss, Marian [Department of Radiotherapy, Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, Krakow 31-115 (Poland)

2014-07-01

The goal of the study was to compare conventional mammography (MG) and contrast-enhanced spectral mammography (CESM) in preoperative women. The study was approved by the local Ethics Committee and all participants provided informed consent. The study included 152 consecutive patients with 173 breast lesions diagnosed on MG or CESM. All MG examinations and consults were conducted in one oncology centre. Non-ionic contrast agent, at a total dose of 1.5 mL/kg body weight, was injected intravenous. Subsequently, CESM exams were performed with a mammography device, allowing dual-energy acquisitions. The entire procedure was done within the oncology centre. Images from low and high energy exposures were processed together and the combination provided an 'iodine' image which outlined contrast up-take in the breast. MG detected 157 lesions in 150 patients, including 92 infiltrating cancers, 12 non-infiltrating cancers, and 53 benign lesions. CESM detected 149 lesions in 128 patients, including 101 infiltrating cancers, 13 non-infiltrating cancers, and 35 benign lesions. CESM sensitivity was 100% (vs. 91% for MG), specificity was 41% (vs. 15% for MG), area under the receiver operating characteristic curve was 0.86 (vs. 0.67 for MG), and accuracy was 80% (vs. 65% for MG) for the diagnosis of breast cancer. Both MG and CESM overestimated lesion sizes compared to histopathology (p < 0.001). CESM may provide higher sensitivity for breast cancer detection and greater diagnostic accuracy than conventional mammography.

Contrast-Enhanced Spectral Mammography: Comparison with Conventional Mammography and Histopathology in 152 Women

International Nuclear Information System (INIS)

Luczyńska, Elzbieta; Heinze-Paluchowska, Sylwia; Dyczek, Sonia; Blecharz, Pawel; Rys, Janusz; Reinfuss, Marian

2014-01-01

The goal of the study was to compare conventional mammography (MG) and contrast-enhanced spectral mammography (CESM) in preoperative women. The study was approved by the local Ethics Committee and all participants provided informed consent. The study included 152 consecutive patients with 173 breast lesions diagnosed on MG or CESM. All MG examinations and consults were conducted in one oncology centre. Non-ionic contrast agent, at a total dose of 1.5 mL/kg body weight, was injected intravenous. Subsequently, CESM exams were performed with a mammography device, allowing dual-energy acquisitions. The entire procedure was done within the oncology centre. Images from low and high energy exposures were processed together and the combination provided an 'iodine' image which outlined contrast up-take in the breast. MG detected 157 lesions in 150 patients, including 92 infiltrating cancers, 12 non-infiltrating cancers, and 53 benign lesions. CESM detected 149 lesions in 128 patients, including 101 infiltrating cancers, 13 non-infiltrating cancers, and 35 benign lesions. CESM sensitivity was 100% (vs. 91% for MG), specificity was 41% (vs. 15% for MG), area under the receiver operating characteristic curve was 0.86 (vs. 0.67 for MG), and accuracy was 80% (vs. 65% for MG) for the diagnosis of breast cancer. Both MG and CESM overestimated lesion sizes compared to histopathology (p < 0.001). CESM may provide higher sensitivity for breast cancer detection and greater diagnostic accuracy than conventional mammography

Academic consortium for the evaluation of computer-aided diagnosis (CADx) in mammography

Science.gov (United States)

Mun, Seong K.; Freedman, Matthew T.; Wu, Chris Y.; Lo, Shih-Chung B.; Floyd, Carey E., Jr.; Lo, Joseph Y.; Chan, Heang-Ping; Helvie, Mark A.; Petrick, Nicholas; Sahiner, Berkman; Wei, Datong; Chakraborty, Dev P.; Clarke, Laurence P.; Kallergi, Maria; Clark, Bob; Kim, Yongmin

1995-04-01

Computer aided diagnosis (CADx) is a promising technology for the detection of breast cancer in screening mammography. A number of different approaches have been developed for CADx research that have achieved significant levels of performance. Research teams now recognize the need for a careful and detailed evaluation study of approaches to accelerate the development of CADx, to make CADx more clinically relevant and to optimize the CADx algorithms based on unbiased evaluations. The results of such a comparative study may provide each of the participating teams with new insights into the optimization of their individual CADx algorithms. This consortium of experienced CADx researchers is working as a group to compare results of the algorithms and to optimize the performance of CADx algorithms by learning from each other. Each institution will be contributing an equal number of cases that will be collected under a standard protocol for case selection, truth determination, and data acquisition to establish a common and unbiased database for the evaluation study. An evaluation procedure for the comparison studies are being developed to analyze the results of individual algorithms for each of the test cases in the common database. Optimization of individual CADx algorithms can be made based on the comparison studies. The consortium effort is expected to accelerate the eventual clinical implementation of CADx algorithms at participating institutions.

Quality control in digital mammography: the noise components

Energy Technology Data Exchange (ETDEWEB)

Leyton, Fernando [Universidade de Tarapaca, Arica (Chile). Centro de Estudios en Ciencias Radiologicas; Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Nogueira, Maria do Socorro, E-mail: mnogue@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Duran, Maria Paz [Clinica Alemana, Santiago (Chile). Dept. de Radiologia; Dantas, Marcelino, E-mail: marcelino@inb.gov.b [Industrias Nucleares do Brasil (INB), Caldas, MG (Brazil). Unidade de Tratamento de Minerios; Ubeda, Carlos, E-mail: cubeda@uta.c [Universidade de Tarapaca, Arica (Chile). Fac. de Ciencias de la Salud

2011-07-01

To measure the linearity of the detector and determine the noise components (quantum, electronic and structural noise) that contributed to losing image quality and to determine the signal noise ratio (SNR) and contrast noise ratio (CNR). This paper describes the results of the implementation of a protocol for quality control in digital mammography performed in two direct digital mammography equipment (Hologic, Selenia) in Santiago of Chile. Shows the results of linearity and noise analysis of the images which establishes the main cause of noise in the image of the mammogram to ensure the quality and optimize procedures. The study evaluated two digital mammography's Selenia, Hologic (DR) from Santiago, Chile. We conducted the assessment of linearity of the detector, the signal noise ratio, contrast noise ratio and was determined the contribution of different noise components (quantum, electronics and structural noise). Used different thicknesses used in clinical practice according to the protocol for quality control in digital mammography of Spanish society of medical physics and NHSBSP Equipment Report 0604 Version 3. The Selenia mammography software was used for the analysis of images and Unfors Xi detector for measuring doses. The mammography detector has a linear performance, the CNR and SNR did not comply with the Protocol for the thicknesses of 60 and 70 mm. The main contribution of the noise corresponds to the quantum noise, therefore it is necessary to adjust and optimize the mammography system. (author)

Quality control in digital mammography: the noise components

International Nuclear Information System (INIS)

Leyton, Fernando; Nogueira, Maria do Socorro; Duran, Maria Paz; Dantas, Marcelino; Ubeda, Carlos

2011-01-01

To measure the linearity of the detector and determine the noise components (quantum, electronic and structural noise) that contributed to losing image quality and to determine the signal noise ratio (SNR) and contrast noise ratio (CNR). This paper describes the results of the implementation of a protocol for quality control in digital mammography performed in two direct digital mammography equipment (Hologic, Selenia) in Santiago of Chile. Shows the results of linearity and noise analysis of the images which establishes the main cause of noise in the image of the mammogram to ensure the quality and optimize procedures. The study evaluated two digital mammography's Selenia, Hologic (DR) from Santiago, Chile. We conducted the assessment of linearity of the detector, the signal noise ratio, contrast noise ratio and was determined the contribution of different noise components (quantum, electronics and structural noise). Used different thicknesses used in clinical practice according to the protocol for quality control in digital mammography of Spanish society of medical physics and NHSBSP Equipment Report 0604 Version 3. The Selenia mammography software was used for the analysis of images and Unfors Xi detector for measuring doses. The mammography detector has a linear performance, the CNR and SNR did not comply with the Protocol for the thicknesses of 60 and 70 mm. The main contribution of the noise corresponds to the quantum noise, therefore it is necessary to adjust and optimize the mammography system. (author)

Implementation of Quality Control Protocol in Mammography: A Serbian Experience

International Nuclear Information System (INIS)

Ciraj Bjelac, O.; Kosutic, D.; Arandjic, D.; Kovacevic, M.

2008-01-01

Mammography is method of choice for early detection of breast cancer. In Serbia, mammography is performed only clinically, although there is a long term plan to introduce mammography as screening method. Currently there are 60 mammography units in practice in Serbia, resulting with 70 000 mammographies annually. The purpose of this paper is preliminary evaluation of the mammography practice in Serbia, having in mind the annual number of examinations and fact that part of examination is performed on women without any clinical signs. For pilot implementation of Quality Control (QC) protocol in mammography, five hospitals with highest workload have been selected, representing the typical mammography practice in Serbia. Developed QC protocol, based on European guidelines for quality assurance in breast cancer screening and diagnosis, actual practice and resources, includes equipment testing and maintenance, staff training and QC management and allocation of responsibilities. Subsequently, it should be applied on the national scale. The survey demonstrated considerable variations in technical parameters that affect image quality and patients doses. Mean glandular doses ranged from 0.12 to 2.8 mGy, while reference optical density ranged from 1.2 to 2.8. Main problems were associated with film processing, viewing conditions and optical density control. The preliminary survey of mammography practice highlighted the need for optimization of radiation protection and training of operating staff, although the survey itself was very valuable learning process for all participants. Furthermore, systematic implementation of QC protocol should provide reliable performance of mammography units and maintain satisfactory image quality and keep patient doses as low as reasonably practical.(author)

Effects of a Computer-Assisted Concept Mapping Learning Strategy on EFL College Students' English Reading Comprehension

Science.gov (United States)

Liu, Pei-Lin; Chen, Chiu-Jung; Chang, Yu-Ju

2010-01-01

The purpose of this research was to investigate the effects of a computer-assisted concept mapping learning strategy on EFL college learners' English reading comprehension. The research questions were: (1) what was the influence of the computer-assisted concept mapping learning strategy on different learners' English reading comprehension? (2) did…

Descriptive study of the quality control in mammography

International Nuclear Information System (INIS)

Gaona, E.; Perdigon C, G.M.; Casian C, G.A.; Azorin N, J.; Diaz G, J.A.I.; Arreola, M.

2005-01-01

The goal of mammography is to provide contrast between a lesion that is possible residing within the breast and normal surrounding tissue. Quality control is essential for maintaining the contrast imaging performance of a mammography system and incorporate tests that are relevant in that they are predictive of future degradation of contrast imaging performance. These tests will also be done at frequency that is high enough to intercept most drifts in quality imaging or performance before they become diagnostically significant. The quality control study has as objective to describe the results of the assessment of quality imaging elements (film optical density, contrast (density difference), uniformity, resolution and noise) of 62 mammography departments without quality control program and comparison these results with a mammography reference department with a quality control program. When comparing the results they allow seeing the clinical utility of to have a quality control program to reduce the errors of mammography interpretation. (Author)

Assessment of the willingness of radiographers in mammography to accept new responsibilities in role extension: Part one - Quantitative analysis

Energy Technology Data Exchange (ETDEWEB)

Moran, S., E-mail: sheila.moran@uon.edu.au [BreastScreen New South Wales, Hunter New England Program (Australia); Warren-Forward, H. [Discipline of Medical Radiation Sciences, University of Newcastle, NSW (Australia)

2011-11-15

Purpose: The success of skill development amongst radiographers in the UK over the last 30 years has stimulated discussion about similar developments in Australia. The introduction of flexible roles and responsibilities may well improve the recruitment and retention issues facing radiographers in mammography by increasing the level of job satisfaction and professional confidence. The main purpose of this study was to investigate the attitudes of BreastScreen Australia radiographers toward mammography screen reading and to determine other areas of interest in role extension. Methods and materials: Questionnaires were sent to radiographers working within Australian BreastScreening programs. The emphasis for this study was on image interpretation, although different areas of role expansion were discussed. The radiographers were asked whether there were any barriers preventing them from becoming screen readers and the levels of supervision and training they thought appropriate for different tasks.They were asked to discuss possible benefits and disadvantages of additional responsibilities. The involvement of radiographers with routine screening was explored as well as the possibility of further training leading to more diversity in their careers. Results: The results highlight the interest that radiographers working in Australia have for role extension in mammography. The radiographers indicated they would feel reasonably confident to undertake image interpretation, but two areas gave them cause for concern - a lack of prior images, and the prospect of no radiologist reading with them. The majority (79%) of radiographers were prepared to undertake extra training and demonstrated that the importance of increased pay for these extra responsibilities (39%) lagged behind the importance of increased professional equity (47%) and increased enjoyment and interest in mammography (66%). The possibility of role expansion being a cause of division in the workforce (pressure to

Assessment of the willingness of radiographers in mammography to accept new responsibilities in role extension: Part one - Quantitative analysis

International Nuclear Information System (INIS)

Moran, S.; Warren-Forward, H.

2011-01-01

Purpose: The success of skill development amongst radiographers in the UK over the last 30 years has stimulated discussion about similar developments in Australia. The introduction of flexible roles and responsibilities may well improve the recruitment and retention issues facing radiographers in mammography by increasing the level of job satisfaction and professional confidence. The main purpose of this study was to investigate the attitudes of BreastScreen Australia radiographers toward mammography screen reading and to determine other areas of interest in role extension. Methods and materials: Questionnaires were sent to radiographers working within Australian BreastScreening programs. The emphasis for this study was on image interpretation, although different areas of role expansion were discussed. The radiographers were asked whether there were any barriers preventing them from becoming screen readers and the levels of supervision and training they thought appropriate for different tasks.They were asked to discuss possible benefits and disadvantages of additional responsibilities. The involvement of radiographers with routine screening was explored as well as the possibility of further training leading to more diversity in their careers. Results: The results highlight the interest that radiographers working in Australia have for role extension in mammography. The radiographers indicated they would feel reasonably confident to undertake image interpretation, but two areas gave them cause for concern - a lack of prior images, and the prospect of no radiologist reading with them. The majority (79%) of radiographers were prepared to undertake extra training and demonstrated that the importance of increased pay for these extra responsibilities (39%) lagged behind the importance of increased professional equity (47%) and increased enjoyment and interest in mammography (66%). The possibility of role expansion being a cause of division in the workforce (pressure to

Mammography calibration qualities establishment in a Mo-Mo clinical system

International Nuclear Information System (INIS)

Correa, E.L.; Santos, L.R. dos; Vivolo, V.; Potiens, M.P.A.

2015-01-01

In this study the mammography calibration qualities were established in a clinical mammography system. The objective is to provide the IPEN instruments calibration laboratory with both mammography calibration methods (using a clinical and an industrial system). The results showed a good behavior of mammography equipment, in terms of kVp, PPV and exposure time. The additional filtration of molybdenum is adequate, air-kerma rates were determined and spectra were obtained. (author)

Mammography calibration qualities establishment in a Mo-Mo clinical system

Energy Technology Data Exchange (ETDEWEB)

Correa, E.L.; Santos, L.R. dos; Vivolo, V.; Potiens, M.P.A., E-mail: educorrea1905@gmail.com [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

In this study the mammography calibration qualities were established in a clinical mammography system. The objective is to provide the IPEN instruments calibration laboratory with both mammography calibration methods (using a clinical and an industrial system). The results showed a good behavior of mammography equipment, in terms of kVp, PPV and exposure time. The additional filtration of molybdenum is adequate, air-kerma rates were determined and spectra were obtained. (author)

Mammography parameters: compression, dose, and discomfort

International Nuclear Information System (INIS)

Blanco, S.; Di Risio, C.; Andisco, D.; Rojas, R.R.; Rojas, R.M.

2017-01-01

Objective: To confirm the importance of compression in mammography and relate it to the discomfort expressed by the patients. Materials and methods: Two samples of 402 and 268 mammographies were obtained from two diagnostic centres that use the same mammographic equipment, but different compression techniques. The patient age range was from 21 to 50 years old. (authors) [es

Performance of clinical mammography: a nationwide study from Denmark

DEFF Research Database (Denmark)

Jensen, Allan; Vejborg, Ilse; Severinsen, Niels

2006-01-01

that clinical mammography worked best in patient populations of purely symptomatic women. Our data indicate that to increase the accuracy of clinical mammography at the community level, the presence of an experienced radiologist should be prioritized ahead of raising the clinic size.......Clinical mammography is the key tool for breast cancer diagnosis, but little is known about the impact of the organisational set-up on the performance. We evaluated whether organisational factors influence the performance of clinical mammography. Clinical mammography data from all clinics...... in Denmark in the year 2000 were collected and linked to cancer outcome. Use of the National Institute of Radiation Hygiene register for identification of radiology clinics ensured comprehensive nationwide registration. We used the final mammographic assessment at the end of the imaging work-up to determine...

An investigation of using the computer for reading and writing in the English classroom in secondary schools in the UK

Directory of Open Access Journals (Sweden)

Bin Zou

2006-10-01

Full Text Available This paper presents an investigation of using the computer in English teaching at the secondary school in the UK, particularly in respect of reading and writing skills. Many studies suggest that the computer brings significant possibilities for promoting the teaching of reading and writing in the English classroom. The computer can enhance the development of reading and writing. This study adopted interviews as research technique and some student teachers in a university and some English teachers in a secondary school in the UK involved this investigation. The findings of this study show that the computer can enhance students’ reading and writing. However, teachers have to learn how to control the process of teaching of reading and writing with the use of the computer.

Comparison of the Mammography, Contrast-Enhanced Spectral Mammography and Ultrasonography in a Group of 116 patients.

Science.gov (United States)

Luczyńska, Elzbieta; Heinze, Sylwia; Adamczyk, Agnieszka; Rys, Janusz; Mitus, Jerzy W; Hendrick, Edward

2016-08-01

Mammography (MG) is the gold-standard in breast cancer detection - the only method documented to reduce breast cancer mortality. Breast ultrasound (US) has been shown to increase sensitivity to breast cancers in screening women with dense breasts. Contrast-enhanced spectral mammography (CESM) is a novel technique intensively developed in the last few years. The goal of this study was to compare the sensitivity, specificity and accuracy of MG, US and CESM in detecting malignant breast lesions. The study included 116 patients. All patients were symptomatic and underwent MG, US and CESM. A radiologist with 20 years of experience in US and MG breast imaging and 1 year of experience in CESM reviewed images acquired in each of the three modalities separately, within an interval of 14-30 days. All identified lesions were confirmed at core biopsy. BI-RADS classifications on US, MG and CESM were compared to histopathology. MG, CESM and US were compared among 116 patients with 137 lesions encountered. Sensitivity of CESM was 100%, significantly higher than that of MG (90%, p<0.004) or US (92%, p<0.01). CESM accuracy was 78%, also higher than MG (69%, p<0.004) and US (70%, p=0.03). There was no statistically significant difference between AUCs for CESM and US (both 0.83). The AUCs of both US and CESM, however, were significantly larger than that of MG (p<0.0004 for each). CESM permitted better detection of malignant lesions than both MG and US, read individually. CESM found lesion enhancement in some benign lesions, as well, yielding a rate of false-positive diagnoses similar to that of MG and US. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Diagnostic accuracy of commercial system for computer-assisted detection (CADx) as an adjunct to interpretation of mammograms

International Nuclear Information System (INIS)

Menna, Sabatino; Di Virgilio, Maria Rosaria; Burke, Paolo; Frigerio, Alfonso; Boglione, Elisa; Ciccarelli, Grazia; Di Filippo, Sabato; Garretti, Licia

2005-01-01

Purpose. To evaluate the diagnostic accuracy of the commercial computer-aided detection CADx system for the reading of mammograms. Materials and methods. The study assessed the Second Look system developed and marketed by CADx Medical Systems, Montreal, Canada. The diagnostic sensitivity was evaluated by means of a retrospective study on 98 consecutive cancers detected at screening by double independent reading. The specificity and the positive predictive value (PPV) for cancer of the CADx system were prospectively evaluated on a second group of 560 consecutive mammograms of asymptomatic women not included in screening program. The radiologist who was present during the test assessed the abnormal mammographic findings by one or more of the following diagnostic procedures: physical examination, additional mammographic detail views with or without magnification,ultrasonography, ultrasound- or mammography guided fine needle aspiration cytology, and core-biopsy. The exams first underwent conventional reading and then a second reading carried out with the aid of the CADx system. Results.The overall diagnostic sensitivity of the CADx system on the 98 screening cancers was 81.6%; in particular it was 89.3% for calcifications, 83.9% for masses and only 37.5% for architectural distortion. The CADx markings for each mammography were 4.7 on average. Identification of invasive carcinoma was independent from tumour size. In the second group of 560 mammograms, the CADx system marked all cases identified as positive by conventional reading and confirmed by biopsy (7/7), but did not permit the detection of any additional cancer. The CADx markings per exam were 4.2 on average, the specificity was 13.7% and the PPV was 0.55% versus 13.7% recall rate of conventional reading. CADx reading led to a 1.96% (11/560) increase of the women necessitating further diagnostic investigation. Conclusions. The results of our study show that the diagnostic sensitivity of the CADx system is lower

Dedicated OO expertise applied to Run II software projects

International Nuclear Information System (INIS)

Amidei, D.

2000-01-01

The change in software language and methodology by CDF and D0 to object-oriented from procedural Fortran is significant. Both experiments requested dedicated expertise that could be applied to software design, coding, advice and review. The Fermilab Run II offline computing outside review panel agreed strongly with the request and recommended that the Fermilab Computing Division hire dedicated OO expertise for the CDF/D0/Computing Division joint project effort. This was done and the two experts have been an invaluable addition to the CDF and D0 upgrade software projects and to the Computing Division in general. These experts have encouraged common approaches and increased the overall quality of the upgrade software. Advice on OO techniques and specific advice on C++ coding has been used. Recently a set of software reviews has been accomplished. This has been a very successful instance of a targeted application of computing expertise, and constitutes a very interesting study of how to move toward modern computing methodologies in HEP

Mammography screening services: market segments and messages.

Science.gov (United States)

Scammon, D L; Smith, J A; Beard, T

1991-01-01

Mammography has become a vital tool for the early detection of breast cancer. Although many organizations and health care facilities are working to educate and motivate women to take advantage of the life saving opportunity that is offered through screening mammography, only twenty percent of women who should be screened actually have the procedure performed. In order to reach women who have not been screened, it is important to learn which factors most strongly motivate those women who do choose to have a mammogram. Depth interviews with 18 women attending a mobile mammography unit were conducted to explore the decision making process of women obtaining mammography screening services and to develop a profile of prevalent emotions, attitudes, and feelings associated with receiving breast cancer screening services. Analysis of the interview transcripts revealed several important themes to which health care professionals can direct marketing and health promotion strategies.

Quality control tests for conventional mammography

International Nuclear Information System (INIS)

Dawod, Alnazer Ahmed Ibrahim

2014-12-01

Mammography is this the test that allows the radiologist to look at images of the inside of the breasts. Mammograms help detect breast cancer early successful treatment of breast cancer depends on that early diagnosis. Breast cancer is a very common condition. About one in every nine women develops breast cancer by the age of eighty. In addition to the clinical examination and self-examination, mammography plays important role in the detection of breast cancer before they become clinically visible tumors. The mammography is the most common test for early detection of breast cancer. Quality control techniques that done ensured importance of this programme to produce images with good diagnostic values and help radiologist to diagnose breast discase easily and avoid exposing patient to radiation hazards.(Author)

Reproducibility of Mammography Units, Film Processing and Quality Imaging

International Nuclear Information System (INIS)

Gaona, Enrique

2003-01-01

The purpose of this study was to carry out an exploratory survey of the problems of quality control in mammography and processors units as a diagnosis of the current situation of mammography facilities. Measurements of reproducibility, optical density, optical difference and gamma index are included. Breast cancer is the most frequently diagnosed cancer and is the second leading cause of cancer death among women in the Mexican Republic. Mammography is a radiographic examination specially designed for detecting breast pathology. We found that the problems of reproducibility of AEC are smaller than the problems of processors units because almost all processors fall outside of the acceptable variation limits and they can affect the mammography quality image and the dose to breast. Only four mammography units agree with the minimum score established by ACR and FDA for the phantom image

Mammography: an update of the EUSOBI recommendations on information for women.

Science.gov (United States)

Sardanelli, Francesco; Fallenberg, Eva M; Clauser, Paola; Trimboli, Rubina M; Camps-Herrero, Julia; Helbich, Thomas H; Forrai, Gabor

2017-02-01

This article summarises the information to be offered to women about mammography. After a delineation of the aim of early diagnosis of breast cancer, the difference between screening mammography and diagnostic mammography is explained. The need to bring images and reports from the previous mammogram (and from other recent breast imaging examinations) is highlighted. Mammography technique and procedure are described with particular attention to discomfort and pain experienced by a small number of women who undergo the test. Information is given on the recall during a screening programme and on the request for further work-up after a diagnostic mammography. The logic of the mammography report and of classification systems such as R1-R5 and BI-RADS is illustrated, and brief but clear information is given about the diagnostic performance of the test, with particular reference to interval cancers, i.e., those cancers that are missed at screening mammography. Moreover, the breast cancer risk due to radiation exposure from mammography is compared to the reduction in mortality obtained with the test, and the concept of overdiagnosis is presented with a reliable estimation of its extent. Information about new mammographic technologies (tomosynthesis and contrast-enhanced spectral mammography) is also given. Finally, frequently asked questions are answered. • Direct digital mammography should be preferred to film-screen or phosphor plates. • Screening (in asymptomatic women) should be distinguished from diagnosis (in symptomatic women). • A breast symptom has to be considered even after a negative mammogram. • Digital breast tomosynthesis increases cancer detection and decreases the recall rate. • Contrast-enhanced spectral mammography can help in cancer detection and lesion characterisation.

Construction of a catalog of X-ray spectra for mammography simulations; Construção de um catálogo de espectros de raios X para simulações em mamografia

Energy Technology Data Exchange (ETDEWEB)

Santos, L.C.S.; Vieira, J.W., E-mail: larissa.css@outlook.com [Instituto Federal de Pernambuco (IFPE), Recife, PE (Brazil). Dept. Acadêmico de Ambiente, Saúde e Segurança; Lima, F.R.A., E-mail: falima@cnen.gov.br [Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife-PE (Brazil)

2017-07-01

Computational Exposure Models (MCEs) allow the simulation of the interaction of radiation with matter by means of Monte Carlo (MC) techniques. Generally, MCEs are composed of phantom, simulator algorithms of radioactive sources and an MC code to simulate the transport, interaction of the radiation with matter and to evaluate the energy deposited in regions of interest. To compose an MCE for simulations in mammography, the construction of a catalog of X-ray spectra was started, based on the catalog model constructed and using until then in MCEs by the Group of Research in Numerical Dosimetry and by the Group of Research in Computational Dosimetry & Embedded Systems (both referenced in this work as GDN). Potential of 25 kV and 35 kV and used target / filter were applied to the tube: Mo / Mo. The file containing the spectra was read correctly by EGSnrc.

Evaluation of glandular dose in conventional and digital mammography systems

International Nuclear Information System (INIS)

Coutinho, Celia Maria Campos

2009-01-01

A survey was conducted to estimate the average glandular dose (D g ) for patients undergoing mammography and to report the distribution of incident air kerma (K i ), patient age, compressed breast thickness and glandular tissue content. From 1183 cranio caudal mammograms clinical data were collected and doses were measured. The survey data included mammograms from six mammography equipment: two screen/film units (SFM), two computed radiography units (CR) and two full-field digital (DR). Mean value for patient age and compressed breast thickness were 57 +-12 y and 5.4 +-1.4 cm, respectively. To investigate the importance of technical characteristics of three different mammography systems and breast glandularity, K i and D g were measured for individual breast of 392 patients from the original sample with compressed breast thickness in the range of 5.5 cm to 6.5 cm using tissue-equivalent phantoms of different glandularities manufactured in this study to mimic both the attenuation and the density of breast tissues. Mean K i value was 10.0 +-3.6 mGy for SFM systems, 12.0 +-3.6 mGy for CR systems and 4.9 +-1.3 mGy for DR systems. Mean D g value was 1.4 +-0.5 mGy for S/F systems, 1.7 +-0.5 mGy for CR systems and 0.9 +-0.2 mGy for D R systems. Statistical analysis for differences in mean values of K i and D g between mammography systems showed significant effect of their technical characteristics (p i and D g , it was observed statistically significant differences between the group of patients with 0 to 50% glandularity and the group of patients with 50 to 100% glandularity. (author)

Mammography practices for radiation protection in Kenya

International Nuclear Information System (INIS)

Shadrack, Anthony K.

2008-01-01

All mammography units in the country, totaling fourteen in number at the time, were evaluated on the basis of performance and practice to come up with useful data for summing up the mammography practice in Kenya. The study was carried out by performing hands-on quality control tests on the units using internationally established protocols. Image quality and dose measurement data were generated in all the centers and clearly indicated that the practice of mammography, more so on optimization viewpoint is so much varied. A standard method was used to obtain these data by use of mammography accreditation phantom. Data from actual patients was also collected in three major centers in Nairobi. On the criteria used for evaluating phantom image quality, ten out of fourteen units did satisfy the set criterion. The average glandular dose was 2.79 mGy per cranio caudal (cc) view of the phantom and 3.27 mGy per cc view for the sampled patients. The internationally recommended dose level for such a view is 3.0 mGy. One worrying observation made was that most units failed on one of the easiest test of mammographic unit assembly. Of most concern was the lack of technique charts for the practice detailing the imaging parameters being employed for the procedure. Most centers do not take the servicing of equipment seriously and others merely ignore even the crucial issues of equipment performance like the automatic exposure control and viewing conditions of the reporting areas.The results of this study calls for the setting up of a programme of optimization of radiological protection in mammography using the experience of other countries that have put in place quality assurance programs, setting and adoption of Dose Reference Levels (DRLs) as part of Quality Assurance (QA). This practice needs an effective quality control program which should start with the selection of appropriate equipment for mammography and the use of qualified personnel including the radiologist, radiographer

An SVM Based Approach for the Analysis Of Mammography Images

Science.gov (United States)

Gan, X.; Kapsokalivas, L.; Skaliotis, A.; Steinhöfel, K.; Tangaro, S.

2007-09-01

Mammography is among the most popular imaging techniques used in the diagnosis of breast cancer. Nevertheless distinguishing between healthy and ill images is hard even for an experienced radiologist, because a single image usually includes several regions of interest (ROIs). The hardness of this classification problem along with the substantial amount of data, gathered from patients' medical history, motivates the use of a machine learning approach as part of a CAD (Computer Aided Detection) tool, aiming to assist radiologists in the characterization of mammography images. Specifically, our approach involves: i) the ROI extraction, ii) the Feature Vector extraction, iii) the Support Vector Machine (SVM) classification of ROIs and iv) the characterization of the whole image. We evaluate the performance of our approach in terms of the SVM's training and testing error and in terms of ROI specificity—sensitivity. The results show a relation between the number of features used and the SVM's performance.

An SVM Based Approach for the Analysis Of Mammography Images

International Nuclear Information System (INIS)

Gan, X.; Kapsokalivas, L.; Skaliotis, A.; Steinhoefel, K.; Tangaro, S.

2007-01-01

Mammography is among the most popular imaging techniques used in the diagnosis of breast cancer. Nevertheless distinguishing between healthy and ill images is hard even for an experienced radiologist, because a single image usually includes several regions of interest (ROIs). The hardness of this classification problem along with the substantial amount of data, gathered from patients' medical history, motivates the use of a machine learning approach as part of a CAD (Computer Aided Detection) tool, aiming to assist radiologists in the characterization of mammography images. Specifically, our approach involves: i) the ROI extraction, ii) the Feature Vector extraction, iii) the Support Vector Machine (SVM) classification of ROIs and iv) the characterization of the whole image. We evaluate the performance of our approach in terms of the SVM's training and testing error and in terms of ROI specificity - sensitivity. The results show a relation between the number of features used and the SVM's performance

Discovering mammography-based machine learning classifiers for breast cancer diagnosis.

Science.gov (United States)

Ramos-Pollán, Raúl; Guevara-López, Miguel Angel; Suárez-Ortega, Cesar; Díaz-Herrero, Guillermo; Franco-Valiente, Jose Miguel; Rubio-Del-Solar, Manuel; González-de-Posada, Naimy; Vaz, Mario Augusto Pires; Loureiro, Joana; Ramos, Isabel

2012-08-01

This work explores the design of mammography-based machine learning classifiers (MLC) and proposes a new method to build MLC for breast cancer diagnosis. We massively evaluated MLC configurations to classify features vectors extracted from segmented regions (pathological lesion or normal tissue) on craniocaudal (CC) and/or mediolateral oblique (MLO) mammography image views, providing BI-RADS diagnosis. Previously, appropriate combinations of image processing and normalization techniques were applied to reduce image artifacts and increase mammograms details. The method can be used under different data acquisition circumstances and exploits computer clusters to select well performing MLC configurations. We evaluated 286 cases extracted from the repository owned by HSJ-FMUP, where specialized radiologists segmented regions on CC and/or MLO images (biopsies provided the golden standard). Around 20,000 MLC configurations were evaluated, obtaining classifiers achieving an area under the ROC curve of 0.996 when combining features vectors extracted from CC and MLO views of the same case.

Effect of area x-ray beam equalization on image quality and dose in digital mammography

Energy Technology Data Exchange (ETDEWEB)

Wong, Jerry; Xu Tong; Husain, Adeel; Le, Huy; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, CA 92697 (United States)

2004-08-21

In mammography, thick or dense breast regions persistently suffer from reduced contrast-to-noise ratio (CNR) because of degraded contrast from large scatter intensities and relatively high noise. Area x-ray beam equalization can improve image quality by increasing the x-ray exposure to under-penetrated regions without increasing the exposure to other breast regions. Optimal equalization parameters with respect to image quality and patient dose were determined through computer simulations and validated with experimental observations on a step phantom and an anthropomorphic breast phantom. Three parameters important in equalization digital mammography were considered: attenuator material (Z = 13-92), beam energy (22-34 kVp) and equalization level. A Mo/Mo digital mammography system was used for image acquisition. A prototype 16 x 16 piston driven equalization system was used for preparing patient-specific equalization masks. Simulation studies showed that a molybdenum attenuator and an equalization level of 20 were optimal for improving contrast, CNR and figure of merit (FOM = CNR{sup 2}/dose). Experimental measurements using these parameters showed significant improvements in contrast, CNR and FOM. Moreover, equalized images of a breast phantom showed improved image quality. These results indicate that area beam equalization can improve image quality in digital mammography.

Risks, radiation dose and image quality of mammography

International Nuclear Information System (INIS)

Menges, V.

1979-01-01

For some time to come, early detection of breast cancer will remain the only way to improve the therapeutical success. Mammography is an absolutely indispensible way to take advantage of this opportunity. Today, mammography is undoubtedly the most reliable method of examination for an early detection of breast cancer. Only mammography can detect carcinomas smaller than the critical tumour size of 1cm. If carried out properly and with present dose levels, it involves hardly any radiation risk. (orig.) [de

Mammography

International Nuclear Information System (INIS)

1975-01-01

This patent reveals a method and instrument for the detection and registration of breast cancer with the aid of X-radiation, i.e. mammography. The breast is irradiated with soft X-rays whereby the radiation beam is scanned with a moving 'stripform' screen and whereby the picture from the 'stripform' screen is recorded by a television camera that moves simultaneously with the strip. The image is then projected on a monitor

Mammography discomfort: a holistic perspective derived from women's experiences

International Nuclear Information System (INIS)

Poulos, Ann; Llewellyn, Gwynnyth

2005-01-01

Purpose: Mammography discomfort has the potential to deter women from attending for regular breast screening. Previous studies have focussed on the pain/discomfort of the mammography procedure itself. The purpose of this study was to consider discomfort from a holistic perspective of the mammography experience derived from the women themselves. Methods: Qualitative research methods were employed. Using theoretical sampling, 12 women who had recently experienced mammography were interviewed. The interview questions aimed to explore the experience of women attending for a mammogram from arrival to departure and beyond in order to identify aspects which potentially increase discomfort. Data analysis involved coding and categorisation and identification of key concepts and their relationships. Results: A conceptual framework was developed that demonstrates the contributors to mammography discomfort and the relationships between these as identified by the women. Conclusions: The conceptual framework has important implications for clinical practice and future research

Interdisciplinary group of mammography (IGM). Quality assurance in mammography

International Nuclear Information System (INIS)

Anon.

1994-01-01

Assurance quality must be a preoccupation of each day in mammography. To be efficient and of low cost it must be discussed between radiologists and physicists; some countries like Federal Republic of Germany, Belgium, United Kingdom, Scandinavia and Netherlands engaged actions to make assurance quality a daily practice

Analysis of mammography on breast fibroadenoma

International Nuclear Information System (INIS)

Fu Xiaomin; Han Benyi; Zhao Yae

2009-01-01

Objective: To study the imaging characteristics of breast fibroadenoma on mammograms. Methods: Mammography of 70 patients with breast fibroadenoma confirmed by pathology were analyzed retrospectively. All patients took breast X-ray of mediolateral oblique projection and craniocaudal projection before operation. Results: In 70 cases with fibroadenoma, mammography revealed 74 foci (36 left breast, 38 right breast) of 62 cases, and failed to reveal lesions in 8 cases. The shape of the lesions was round or round-like lesion in 60(31%). The border was well-defined in 46 masses, partly well-outlined in 14 and ill-defined in 4. 'Membranoid sign' can be seen in 40 cases. Conclusion: Typical X-ray findings of breast fibroadenoma is very important, mammography is a good method of choice in diagnosis of fibroadenoma. (authors)

Contrast-enhanced spectral mammography: Does mammography provide additional clinical benefits or can some radiation exposure be avoided?

Science.gov (United States)

Fallenberg, Eva Maria; Dromain, Clarisse; Diekmann, Felix; Renz, Diane M; Amer, Heba; Ingold-Heppner, Barbara; Neumann, Avidan U; Winzer, Klaus J; Bick, Ulrich; Hamm, Bernd; Engelken, Florian

2014-07-01

The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) with mammography (MG) and combined CESM + MG in terms of detection and size estimation of histologically proven breast cancers in order to assess the potential to reduce radiation exposure. A total of 118 patients underwent MG and CESM and had final histological results. CESM was performed as a bilateral examination starting 2 min after injection of iodinated contrast medium. Three independent blinded radiologists read the CESM, MG, and CESM + MG images with an interval of at least 4 weeks to avoid case memorization. Sensitivity and size measurement correlation and differences were calculated, average glandular dose (AGD) levels were compared, and breast densities were reported. Fisher's exact and Wilcoxon tests were performed. A total of 107 imaging pairs were available for analysis. Densities were ACR1: 2, ACR2: 45, ACR3: 42, and ACR4: 18. Mean AGD was 1.89 mGy for CESM alone, 1.78 mGy for MG, and 3.67 mGy for the combination. In very dense breasts, AGD of CESM was significantly lower than MG. Sensitivity across readers was 77.9 % for MG alone, 94.7 % for CESM, and 95 % for CESM + MG. Average tumor size measurement error compared to postsurgical pathology was -0.6 mm for MG, +0.6 mm for CESM, and +4.5 mm for CESM + MG (p < 0.001 for CESM + MG vs. both modalities). CESM alone has the same sensitivity and better size assessment as CESM + MG and was significantly better than MG with only 6.2 % increase in AGD. The combination of CESM + MG led to systematic size overestimation. When a CESM examination is planned, additional MG can be avoided, with the possibility of saving up to 61 % of radiation dose, especially in patients with dense breasts.

Barriers to Mammography among Inadequately Screened Women

Science.gov (United States)

Stoll, Carolyn R. T.; Roberts, Summer; Cheng, Meng-Ru; Crayton, Eloise V.; Jackson, Sherrill; Politi, Mary C.

2015-01-01

Mammography use has increased over the past 20 years, yet more than 30% of women remain inadequately screened. Structural barriers can deter individuals from screening, however, cognitive, emotional, and communication barriers may also prevent mammography use. This study sought to identify the impact of number and type of barriers on mammography…

Image quality in conventional film screen system, digital phosphor storage plate mammography in magnification technique and digital mammography in CCD-technique

International Nuclear Information System (INIS)

Schulz-Wendtland, R.; Aichinger, U.; Boehner, C.; Dobritz, M.; Bautz, W.; Saebel, M.

2000-01-01

Purpose: Comparison of image quality between conventional film screen system, digital phosphor storage plate mammography in magnification technique and digital mammography in CCD-technique. Materials and Methods: Radiograms of a RMI-mammography phantom were acquired using a conventional film screen system, two digital storage plate systems and two digital systems in CCD-technique. Additionally, the radiograms of one digital phosphor storage plate system were post-processed emphasizing contrast and included in the comparison. Results: The detectability of details was the best with the digital mammography in CCD-technique in comparison with the conventional film screen technique resp. digital phosphor storage plate in magnification technique. Conclusions: Based on these results there is the possibility to replace the conventional film screen system by further studies - this has to be confirmed. (orig.) [de

Computer-based programs on acquisition of reading skills in schoolchildren (review of contemporary foreign investigations

Directory of Open Access Journals (Sweden)

Prikhoda N.A.

2015-03-01

Full Text Available The article presents a description of 17 computer-based programs, which were used over the last 5 years (2008—2013 in 15 studies of computer-assisted reading instruction and intervention of schoolchildren. The article includes a description of specificity of various terms used in the above-mentioned studies and the contents of training sessions. The article also carries out a brief analysis of main characteristics of computer-based techniques — language of instruction, age and basic characteristics of students, duration and frequency of training sessions, dependent variables of education. Special attention is paid to efficiency of acquisition of different reading skills through computer-based programs in comparison to traditional school instruction.

Traceability and quality control in mammography: measurements and models

International Nuclear Information System (INIS)

Peixoto, Jose Guilherme Pereira

2002-10-01

The success of a treatment or diagnosis using radiation, depends on the optimization of the dose determination to be administered for the patient and on the beam radiation quality. It is recognized by the international guidelines that it is necessary to improve calibration services for mammography beams in order to improve the quality of clinical diagnosis. Major efforts have been made by several laboratories in order to establish an appropriate and traceable calibration infrastructure and to provide the basis for a quality control program in mammography. The contribution of the radiation metrology network to the mammography services is reviewed in this work. Steps required for the implementation of a mammography calibration system using a constant potential x-ray and a clinical mammography x-ray machine are presented. The various qualities of mammography radiation discussed in this work are in accordance with the IEC 61674 and the AAPM recommendations. This work also presents the methodology and the procedures to maintain and to disseminate the traceability at the x-ray mammography range, describing the interlaboratory comparison performed at LNMRI/IRD/CNEN and at the IPEN/CNEN using the secondary standard ionization chambers traceable with the international standard. It assesses the inter-laboratory comparison consistency and decides whether a questionable value should or not be accepted, using the residual method. This thesis discusses the uncertainties involved in all steps of the calibration chain in accord once with the ISO recommendations. (author)

Monte Carlo derivation of filtered tungsten anode X-ray spectra for dose computation in digital mammography*

Science.gov (United States)

Paixão, Lucas; Oliveira, Bruno Beraldo; Viloria, Carolina; de Oliveira, Marcio Alves; Teixeira, Maria Helena Araújo; Nogueira, Maria do Socorro

2015-01-01

Objective Derive filtered tungsten X-ray spectra used in digital mammography systems by means of Monte Carlo simulations. Materials and Methods Filtered spectra for rhodium filter were obtained for tube potentials between 26 and 32 kV. The half-value layer (HVL) of simulated filtered spectra were compared with those obtained experimentally with a solid state detector Unfors model 8202031-H Xi R/F & MAM Detector Platinum and 8201023-C Xi Base unit Platinum Plus w mAs in a Hologic Selenia Dimensions system using a direct radiography mode. Results Calculated HVL values showed good agreement as compared with those obtained experimentally. The greatest relative difference between the Monte Carlo calculated HVL values and experimental HVL values was 4%. Conclusion The results show that the filtered tungsten anode X-ray spectra and the EGSnrc Monte Carlo code can be used for mean glandular dose determination in mammography. PMID:26811553

Monte Carlo derivation of filtered tungsten anode X-ray spectra for dose computation in digital mammography

Directory of Open Access Journals (Sweden)

Lucas Paixão

2015-12-01

Full Text Available Abstract Objective: Derive filtered tungsten X-ray spectra used in digital mammography systems by means of Monte Carlo simulations. Materials and Methods: Filtered spectra for rhodium filter were obtained for tube potentials between 26 and 32 kV. The half-value layer (HVL of simulated filtered spectra were compared with those obtained experimentally with a solid state detector Unfors model 8202031-H Xi R/F & MAM Detector Platinum and 8201023-C Xi Base unit Platinum Plus w mAs in a Hologic Selenia Dimensions system using a direct radiography mode. Results: Calculated HVL values showed good agreement as compared with those obtained experimentally. The greatest relative difference between the Monte Carlo calculated HVL values and experimental HVL values was 4%. Conclusion: The results show that the filtered tungsten anode X-ray spectra and the EGSnrc Monte Carlo code can be used for mean glandular dose determination in mammography.

Mammography screening among Arab American women in metropolitan Detroit.

Science.gov (United States)

Schwartz, Kendra; Fakhouri, Monty; Bartoces, Monina; Monsur, Joseph; Younis, Amani

2008-12-01

Mammography screening behavior has not been well studied among Middle Eastern immigrant women. We conducted a telephone survey of 365 Arab American women residing in metropolitan Detroit, home to one of the largest populations of Middle Eastern immigrants in the US, to determine prevalence of factors associated with mammography, and attitudes and beliefs regarding mammography screening. Of 365 participants, only five were born in the US. Mean age was 53.2 years (SD 10.8). Two hundred twelve (58.1%) reported having mammogram every 1-2 years; 70% ever had mammogram. Age 50-64 years, having health insurance, married status, being in the US over 10 years, and being Lebanese were associated with mammography every 1-2 years. After adjusting for demographic factors, perceived seriousness of disease, general health motivation, and having fewer barriers were associated with more frequent screening. Appropriate mammography screening is decreased in this group. Targeted outreach regarding screening is appropriate for this population; however, lack of insurance may prevent adequate follow-up.

Are phantoms useful for predicting the potential of dose reduction in full-field digital mammography?

International Nuclear Information System (INIS)

Gennaro, Gisella; Katz, Luc; Souchay, Henri; Alberelli, Claudio; Maggio, Cosimo di

2005-01-01

A phantom study was performed in full-field digital mammography to investigate the opportunity and the magnitude of a possible dose reduction that would leave the image quality above the accepted thresholds associated with some classical phantoms. This preliminary work is intended to lay the groundwork for a future clinical study on the impact of dose reduction on clinical results. Three different mammography phantoms (ACR RMI 156, CIRS 11A and CDMAM 3.4) were imaged by a full-field digital mammography unit (GE Senographe 2000D) at different dose levels. Images were rated by three observers with softcopy reading and scoring methods specific to each phantom. Different types of data analysis were applied to the ACR (American College of Radiology) and the other two phantoms, respectively. With reference to the minimum acceptance score in screen/film accreditation programmes, the ACR phantom showed that about 45% dose reduction could be applied, while keeping the phantom scores above that threshold. A relative comparison was done for CIRS and CDMAM, for which no threshold is defined. CIRS scoring remained close to the reference level down to 40% dose reduction, the inter- and intra-observer variability being the main source of uncertainty. Contrast-detail curves provided by CDMAM overlapped down to 50% dose reduction, at least for object contrast values ranging between 30% and 3%. This multi-phantom study shows the potential of further reducing the dose in full-field digital mammography beyond the current values. A common dose reduction factor around 50% seems acceptable for all phantoms. However, caution is required before extrapolating the results for clinical use, given the limitations of these widely used phantoms, mainly related to their limited dynamic range and uniform background

Mammography and ultrasound in the evaluation of male breast disease

Energy Technology Data Exchange (ETDEWEB)

Munoz Carrasco, Rafaela; Alvarez Benito, Marina; Raya Povedano, Jose Luis [Hospital Universitario ' Reina Sofia' , Radiology Department, Cordoba (Spain); Munoz Gomariz, Elisa [Hospital Universitario ' Reina Sofia' , Support Unit for Research, Cordoba (Spain); Martinez Paredes, Maria [University of Cordoba, Radiology and Physical Medicine Area, Cordoba (Spain)

2010-12-15

To assess clinical variables that may be useful in differentiating gynaecomastia from carcinoma and to analyse the contribution of mammography and ultrasound to the evaluation of male breast disease. All men who underwent mammography and/or ultrasound between 1993 and 2006 in our hospital were retrospectively evaluated. Clinical characteristics in patients with gynaecomastia and those with carcinoma were compared. Radiological findings were classified according to the BI-RADS (Breast Imaging Reporting and Data System) criteria. The diagnostic performance of physical examination, mammography and ultrasound was determined and compared. A total of 628 patients with 518 mammograms and 423 ultrasounds were reviewed. The final diagnoses were: 19 carcinomas, 526 gynaecomastias, 84 other benign conditions and 25 normal. There were statistically significant differences in age, bilateral involvement, clinical presentation and physical examination between patients with carcinoma and those with gynaecomastia. The diagnostic performance of physical examination was lower than that of mammography and ultrasound (p < 0.05 for specificity). Mammography was the most sensitive (94.7%) and ultrasound the most specific (95.3%) for detection of malignancy (p > 0.05). We propose an algorithm for the use of mammography and ultrasound in men. Mammography and ultrasound, with a negative predictive value close to 100%, make it possible to avoid very many unnecessary surgical procedures in men. (orig.)

Organization and standards of screening and diagnostic mammography

International Nuclear Information System (INIS)

Linderbraten, L.D.; Chikirdin, Eh.G.; Rozhkova, N.I.

1999-01-01

Problem of organizing and standards of the reference and diagnostic mammography in our country is discussed. Attention is paid to the terminology, accreditation of mammographic establishments and specialists, specifications of equipment, image quality, mammography results processing, radiation doses [ru

Performance of computer-aided detection applied to full-field digital mammography in detection of breast cancers

International Nuclear Information System (INIS)

Sadaf, Arifa; Crystal, Pavel; Scaranelo, Anabel; Helbich, Thomas

2011-01-01

Objective: The aim of this retrospective study was to evaluate performance of computer-aided detection (CAD) with full-field digital mammography (FFDM) in detection of breast cancers. Materials and Methods: CAD was retrospectively applied to standard mammographic views of 127 cases with biopsy proven breast cancers detected with FFDM (Senographe 2000, GE Medical Systems). CAD sensitivity was assessed in total group of 127 cases and for subgroups based on breast density, mammographic lesion type, mammographic lesion size, histopathology and mode of presentation. Results: Overall CAD sensitivity was 91% (115 of 127 cases). There were no statistical differences (p > 0.1) in CAD detection of cancers in dense breasts 90% (53/59) versus non-dense breasts 91% (62/68). There was statistical difference (p 20 mm 97% (22/23). Conclusion: CAD applied to FFDM showed 100% sensitivity in identifying cancers manifesting as microcalcifications only and high sensitivity 86% (71/83) for other mammographic appearances of cancer. Sensitivity is influenced by lesion size. CAD in FFDM is an adjunct helping radiologist in early detection of breast cancers.

Decision optimization of case-based computer-aided decision systems using genetic algorithms with application to mammography

International Nuclear Information System (INIS)

Mazurowski, Maciej A; Habas, Piotr A; Zurada, Jacek M; Tourassi, Georgia D

2008-01-01

This paper presents an optimization framework for improving case-based computer-aided decision (CB-CAD) systems. The underlying hypothesis of the study is that each example in the knowledge database of a medical decision support system has different importance in the decision making process. A new decision algorithm incorporating an importance weight for each example is proposed to account for these differences. The search for the best set of importance weights is defined as an optimization problem and a genetic algorithm is employed to solve it. The optimization process is tailored to maximize the system's performance according to clinically relevant evaluation criteria. The study was performed using a CAD system developed for the classification of regions of interests (ROIs) in mammograms as depicting masses or normal tissue. The system was constructed and evaluated using a dataset of ROIs extracted from the Digital Database for Screening Mammography (DDSM). Experimental results show that, according to receiver operator characteristic (ROC) analysis, the proposed method significantly improves the overall performance of the CAD system as well as its average specificity for high breast mass detection rates

Breast cancer imaging: Mammography among women of up to 45 years

International Nuclear Information System (INIS)

Schnejder-Wilk, A.

2010-01-01

Background: Among women under the age of 40, screening mammography examinations are not performed routinely. An ultrasonography scan is considered to be a basic breast imaging examination among younger women. The purpose of this study was to analyze mammography images, as well as to evaluate the usefulness and role of mammography in breast cancer diagnostic processes in women of up to 45 years, based on own experience. Material/Methods: A retrospective analysis of mammography images, including 144 cases of breast cancer diagnosed in the group of 140 women of 45 years of age. All the patients underwent pre-treatment mammography and surgery procedure. The images were evaluated in accordance to BIRADS criteria. Lesions detectable in mammography were grouped as follows: spiculated mass; nonmicrocalcified oval/round mass; microcalcified mass (regardless of shape); microcalcifications; architectural distortion; breast tissue asymmetry. Results: The most common mammographic symptom was solid tumor (41%), followed by microcalcified tumors (20.8%). Clusters of microcalcifications constituted 17.4% of mammography findings. In 4.9% of mammography scans, examination did not reveal any pathological lesions. Conclusions: Breast cancer mammograms of women aged up to 45 years do not differ from diagnostic pictures of breast cancer in older women. The diagnostic appearance of breast cancer in 1/3 of the patients involved microcalcifications detectable only on mammograms. All the women with suspicion of breast cancer should have their mammography examinations performed, irrespective of ultrasonography scans. (author)

Development and Use of an EFL Reading Practice Application for an Android Tablet Computer

Science.gov (United States)

Ishikawa, Yasushige; Smith, Craig; Kondo, Mutsumi; Akano, Ichiro; Maher, Kate; Wada, Norihisa

2014-01-01

This paper reports on the use of an English-language reading practice application for an Android tablet computer with students who are not native speakers of English. The application materials for vocabulary learning in reading-passage contexts were created to include words from a database of low-frequency and technical noun-verb collocations…

Mammography: an update of the EUSOBI recommendations on information for women

OpenAIRE

Sardanelli, Francesco; Fallenberg, Eva M.; Clauser, Paola; Trimboli, Rubina M.; Camps-Herrero, Julia; Helbich, Thomas H.; Forrai, Gabor

2016-01-01

Abstract This article summarises the information to be offered to women about mammography. After a delineation of the aim of early diagnosis of breast cancer, the difference between screening mammography and diagnostic mammography is explained. The need to bring images and reports from the previous mammogram (and from other recent breast imaging examinations) is highlighted. Mammography technique and procedure are described with particular attention to discomfort and pain experienced by a sma...

Reading screening mammograms - Attitudes among radiologists and radiographers about skill mix

DEFF Research Database (Denmark)

Johansen, Lena Westphal; Brodersen, John

2011-01-01

INTRODUCTION: Because of shortage of personnel for the Danish mammography screening programme, the aim of this study was to investigate the attitudes of radiologists and radiographers towards a future implementation of radiographers reading screening mammograms. MATERIALS AND METHODS: Seven...... of managers, and improved working relations. Organization related obstacles: shortage of radiographers and negative attitudes of managers. Professional related possibilities: positive experience with skill mix. Professional related obstacles: worries about negative consequences for the training...... and financial consequences of skill mix. Despite of this all radiologists and radiographers experienced with skill mix were strong advocates for reading radiographers....

Diagnostic accuracy and recall rates for digital mammography and digital mammography combined with one-view and two-view tomosynthesis: results of an enriched reader study.

Science.gov (United States)

Rafferty, Elizabeth A; Park, Jeong Mi; Philpotts, Liane E; Poplack, Steven P; Sumkin, Jules H; Halpern, Elkan F; Niklason, Loren T

2014-02-01

The purpose of this study was to compare two methods of combining tomosynthesis with digital mammography by assessing diagnostic accuracy and recall rates for digital mammography alone and digital mammography combined with one-view tomosynthesis and two-view tomosynthesis. Three hundred ten cases including biopsy-proven malignancies (51), biopsy-proven benign findings (47), recalled screening cases (138), and negative screening cases (74) were reviewed by 15 radiologists sequentially using digital mammography, adding one-view tomosynthesis, and then two-view tomosynthesis. Cases were assessed for recall and assigned a BI-RADS score and probability of malignancy for each imaging method. Diagnostic accuracy was assessed using receiver operating characteristic (ROC) analysis. Screening recall rates were compared using pooled logistical regression analysis. A p value of tomosynthesis, and DM plus two-view tomosynthesis was 0.828, 0.864, and 0.895, respectively. Both one-view and two-view tomosynthesis plus DM were significantly better than DM alone (Δ AUCs 0.036 [p = 0.009] and 0.068 [p tomosynthesis, and DM plus two-view tomosynthesis were 44.2%, 27.2%, and 24.0%, respectively. Combined with DM, one-view and two-view tomosynthesis both showed significantly lower noncancer recall rates than digital mammography alone (p tomosynthesis showed a significantly lower recall rate than digital mammography with one-view tomosynthesis (p tomosynthesis compared with digital mammography alone. Compared with digital mammography, diagnostic sensitivity for invasive cancers increased with the addition of both one-view (Δ12.0%, p tomosynthesis. The addition of one-view tomosynthesis to conventional digital mammography improved diagnostic accuracy and reduced the recall rate; however, the addition of two-view tomosynthesis provided twice the performance gain in diagnostic accuracy while further reducing the recall rate.

Control of quality in mammography

International Nuclear Information System (INIS)

2006-10-01

The present protocol of quality control/quality assurance in mammography is the result of the work of two regional projects realised in Latin America within the frame of ARCAL with the support of the IAEA. The first is ARCAL LV (RLA/6/043) project on quality assurance/quality control in mammography studies which analysed the present situation of the mammography in the member countries of the project which include: Bolivia, Colombia, Costa Rica, Cuba, El Salvador, Guatemala, Nicaragua, Panama, Paraguay, Peru, Dominican Republic and Republic of Venezuela and the second is ARCAL XLIX (RLA/9/035) project, whose members were Brazil, Colombia, Cuba, Chile, Mexico, and Peru, worked the application of Basic Safety Standards for the protection against ionising radiation with the aim to improve radiation protection in X-ray diagnosis medical practices through the implementation of the Basic Safety Standards (BSS) related to x-ray diagnosis in selected hospitals located in each country involved in the project. The work of both projects had been consolidated and harmonized in the present publication

Understanding women's mammography intentions: a theory-based investigation.

Science.gov (United States)

Naito, Mikako; O'Callaghan, Frances V; Morrissey, Shirley

2009-01-01

The present study compared the utility of two models (the Theory of Planned Behavior and Protection Motivation Theory) in identifying factors associated with intentions to undertake screening mammography, before and after an intervention. The comparison was made between the unique components of the two models. The effect of including implementation intentions was also investigated. Two hundred and fifty-one women aged 37 to 69 years completed questionnaires at baseline and following the delivery of a standard (control) or a protection motivation theory-based informational intervention. Hierarchical multiple regressions indicated that theory of planned behavior variables were associated with mammography intentions. Results also showed that inclusion of implementation intention in the model significantly increased the association with mammography intentions. The findings suggest that future interventions aiming to increase screening mammography participation should focus on the theory of planned behavior variables and that implementation intention should also be targeted.

Cancer of the breast: induction by radiation and role of mammography

Energy Technology Data Exchange (ETDEWEB)

Simon, N

1977-10-01

Conflict in the management of cancer of the breast exists. Diagnosis by x-ray mammography provides early effective treatment, but x-ray exposure to the breast is cancerogenic. Prudence requires the use of low dose x-rays in mammography, and limits the use of x-ray mammography in the young. Guide lines for the indications for mammography are changing, and large scale population exposure to radiation should await results of demonstration projects in the United States.

Effectiveness of a Mobile Mammography Program.

Science.gov (United States)

Stanley, Elizabeth; Lewis, Madelene C; Irshad, Abid; Ackerman, Susan; Collins, Heather; Pavic, Dag; Leddy, Rebecca J

2017-12-01

Mobile mammography units have increasingly been used to address patient health care disparities; however, there are limited data comparing mobile units to stationary sites. This study aims to evaluate the characteristics of women who underwent mammography screening in a mobile unit versus those who underwent mammography screening at a cancer center. In this retrospective study, we analyzed all screening mammography examinations performed in a mobile unit in 2014 (n = 1433 examinations). For comparison, we randomized and reviewed an equivalent number of screening mammography examinations performed at our cancer center in 2014 (n = 1434 examinations). BI-RADS assessment, adherence to follow-up, biopsies performed, cancer detection rate, and sociodemographic variables were recorded. An independent-samples t test was conducted to identify potential differences in age between cancer center patients and mobile unit patients. Chi-square analyses were used to test for associations between location and factors such as health insurance, race, marital status, geographic area, adherence to screening guidelines, recall rate, adherence to follow-up, and cancer detection rates. Patients visiting our cancer center (mean = 57.74 years; SD = 10.55) were significantly older than those visiting the mobile unit (mean = 52.58 years; SD = 8.19; p mobile van (cancer center = 3.70%, mobile unit = 38.73%). There was a significant association between screening location and patient race (χ 2 = 118.75, p mobile unit = 33.30%), more black patients being screened in the mobile van (cancer center = 49.30%, mobile unit = 54.15%), and more Hispanic patients being screened in the mobile van (cancer center = 1.05%, mobile unit = 6.77%). There was a significant association between location and patient marital status (χ 2 = 135.61, p mobile unit = 38.31%), more single patients screened in the mobile van (cancer center = 25.17%, mobile unit = 34.47%), and more widowed patients being screened at the

Exposure and roentgen-area-product in xeromammography and conventional mammography

Energy Technology Data Exchange (ETDEWEB)

Baxt, J H; Bushong, S C; Glaze, S; Kothari, S [Baylor Univ., Houston, Tex. (USA). Coll. of Medicine

1976-01-01

X-ray mammography is assuming increasing importance in the early detection of breast cancer. The principal disadvantage to conventional mammography is high patient dose. Xeromammography offers three advantages over conventional mammography: (a) lower patient dose, (b) better image quality and (c) no special mammography tube required. A transmission ionization chamber and thermoluminescent dosimeters were used to measure the roentgen-area-product and the exposure for three view examination. Average roentgen-area-product values of 6500 and 4200 R-cm/sup 2/ were observed for conventional mammography and xeromammography respectively. The medial surface of the breast received the highest radiation exposure for both types of examinations and this was shown to be 11.5 and 5.1 R respectively. Omission of the axillary view from the examination reduces the patient dose in both types by approximately 60 %.

Quality assurance programme at Slovak mammography departments

International Nuclear Information System (INIS)

Horvathova, M.; Nikodemova, D.

2004-01-01

A co-ordinated research program (CRP) for optimisation of image quality in mammography in some Eastern European countries has been initiated by IAEA between 1999 and 2001 and the Slovak Republic took part in this program. The aim of this program was to implement the European QA/QC protocol in a sample of mammography departments and to achieve improvement of the image quality and patient dose reduction. On the national level 28 mammography units were chosen in accordance with equipment performance for quality control programme at this departments, for the first part of the mammography audit in the years 2002-2004. Realisation of CRP project contains: 1) Collection and evaluation of clinical images in agreement with EC criteria; 2) Evaluation of the image quality using mammography test phantom; 3) Measurements of the ESD at patients using TLD; 4) Intercomparison of TLD system calibration with IAEA laboratory; 5) Film reject analysis; 6) Implementation of QC program to the mammography units. The measurements of ESD on patients were performed with TLD (LiF 700 Harshaw). In the 6 month period were collected the results of measurements of: 1) object thickness compensation (measured weekly); 2) long time reproducibility (measured daily); 3) phantom image quality on the standard RMI 156 phantom (measured weekly); 4) ESD on phantom with TLD (once during the audit). Automatic Exposure Control compensation for the object thickness variation was measured by exposing different PMMA plates of thickness ranging from 20 to 60 mm, using the clinical settings. The long term reproducibility has been assessed from the measurements of the optical density and mAs product resulted from the exposure on the PMMA plates. In order to estimate the quality of the images the RMI 156 mammography accreditation phantom was chosen. The accreditation phantom contains test objects which simulate small structures seen in the breast (microcalcifications, fibrils, and tumor like masses). Results of

Does health status influence intention regarding screening mammography?

International Nuclear Information System (INIS)

Park, Keeho; Park, Jong-Hyock; Park, Jae-Hyun; Kim, Hui-Jeong; Park, Bo-Yoon

2010-01-01

We analyzed information surveyed from a community-based sample of Korean women older than 40 years of age to understand the relationships between health status and screening behavior. In a cross-sectional population-based study, a two-stage, geographically stratified household-based sampling design was used for assembly of a probability sample of women aged 40-69 years living in Gunpo in Korea, resulting in a total sample size of 503 women. The primary outcome variable for this analysis was the respondent's intention to obtain a mammogram. Predictor variables included health status and other factors known to influence the use of cancer screening, such as age, education, income, marital status and the presence of co-morbid illnesses. Health status was assessed by using the EuroQol (EQ-5D). The median EQ visual analogue scale score was 75.0, ranging from 20 to 100. In bivariate analyses, the percentage of women reporting to have intention toward mammography use decreased with worsening health status. Women who had problems with mobility or anxiety/depression showed lower intention to undergo future screening mammography. Multivariate logistic regression confirmed that health status was significantly associated with intention toward mammography use. Anxiety or depression was an independent predictor of future screening mammography use. Health status is significantly associated with intention regarding screening mammography use. Physicians or other health professionals should be aware that health status is an important component for health promotion, and should pay more attention to clients' possible vulnerability in screening mammography use due to their poor health status. (author)

Dual-energy mammography: simulation studies

International Nuclear Information System (INIS)

Bliznakova, K; Kolitsi, Z; Pallikarakis, N

2006-01-01

This paper presents a mammography simulator and demonstrates its applicability in feasibility studies in dual-energy (DE) subtraction mammography. This mammography simulator is an evolution of a previously presented x-ray imaging simulation system, which has been extended with new functionalities that are specific for DE simulations. The new features include incident exposure and dose calculations, the implementation of a DE subtraction algorithm as well as amendments to the detector and source modelling. The system was then verified by simulating experiments and comparing their results against published data. The simulator was used to carry out a feasibility study of the applicability of DE techniques in mammography, and more precisely to examine whether this modality could result in better visualization and detection of microcalcifications. Investigations were carried out using a 3D breast software phantom of average thickness, monoenergetic and polyenergetic beam spectra and various detector configurations. Dual-shot techniques were simulated. Results showed the advantage of using monoenergetic in comparison with polyenergetic beams. Optimization studies with monochromatic sources were carried out to obtain the optimal low and high incident energies, based on the assessment of the figure of merit of the simulated microcalcifications in the subtracted images. The results of the simulation study with the optimal energies demonstrated that the use of the DE technique can improve visualization and increase detectability, allowing identification of microcalcifications of sizes as small as 200 μm. The quantitative results are also verified by means of a visual inspection of the synthetic images

Does the accuracy of single reading with CAD (computer-aided detection) compare with that of double reading?: A review of the literature

International Nuclear Information System (INIS)

Bennett, R.L.; Blanks, R.G.; Moss, S.M.

2006-01-01

Aim: To examine current evidence to determine whether the accuracy of single reading with computed-aided detection (CAD) compares with that of double reading. Methods: We performed a literature review to identify studies where both protocols had been investigated and compared. We identified eight studies that compared single reading with CAD against double reading, of which six reported on comparisons of both sensitivity and specificity. Results: Of the six studies identified, three showed no differences in either sensitivity or specificity. One showed single reading with CAD had a higher sensitivity at the same specificity, another that single reading with CAD had a higher specificity at the same sensitivity. However, one study, in a real-life setting, showed that single reading with CAD had a higher sensitivity but a lower specificity. Conclusion: As the majority of the studies were not in a real-life setting, used test sets, lacked sufficient training in the use of CAD and simulated double reading (using a protocol of recall if one suggests), current evidence is therefore limited as to the accuracy, in terms of sensitivity and specificity, of single reading with CAD in comparison with the most common practice in the UK of double reading using a protocol of consensus or arbitration

Quality assurance in mammography

International Nuclear Information System (INIS)

Fosmark, H.; Olerud, H.M.

1992-01-01

Guidelines in mammography are given, including competence of staff, performance of equipment and quality control procedures. The purpose of the guidelines is to ensure optimum diagnostic quality. 5 refs

The Future of Contrast-Enhanced Mammography.

Science.gov (United States)

Covington, Matthew F; Pizzitola, Victor J; Lorans, Roxanne; Pockaj, Barbara A; Northfelt, Donald W; Appleton, Catherine M; Patel, Bhavika K

2018-02-01

The purpose of this article is to discuss facilitators of and barriers to future implementation of contrast-enhanced mammography (CEM) in the United States. CEM provides low-energy 2D mammographic images analogous to digital mammography and contrast-enhanced recombined images that allow assessment of neovascularity similar to that offered by MRI. The utilization of CEM in the United States is currently low but could increase rapidly given the many potential indications for its clinical use.

Dual-energy contrast-enhanced digital mammography: initial clinical results

International Nuclear Information System (INIS)

Dromain, Clarisse; Thibault, Fabienne; Tardivon, Anne; Muller, Serge; Rimareix, Francoise; Delaloge, Suzette; Balleyguier, Corinne

2011-01-01

To assess the diagnostic accuracy of Dual-Energy Contrast-Enhanced Digital Mammography (CEDM) as an adjunct to mammography (MX) versus MX alone and versus mammography plus ultrasound (US). 120 women with 142 suspect findings on MX and/or US underwent CEDM. A pair of low- and high-energy images was acquired using a modified full-field digital mammography system. Exposures were taken in MLO at 2 min and in CC at 4 min after the injection of 1.5 ml/kg of an iodinated contrast agent. One reader evaluated MX, US and CEDM images during 2 sessions 1 month apart. Sensitivity, specificity, and area under the ROC curve were estimated. The results from pathology and follow-up identified 62 benign and 80 malignant lesions. Areas under the ROC curves were significantly superior for MX+CEDM than it was for MX alone and for MX+US using BI-RADS. Sensitivity was higher for MX+CEDM than it was for MX (93% vs. 78%; p < 0.001) with no loss in specificity. The lesion size was closer to the histological size for CEDM. All 23 multifocal lesions were correctly detected by MX+CEDM vs. 16 and 15 lesions by MX and US respectively. Initial clinical results show that CEDM has better diagnostic accuracy than mammography alone and mammography+ultrasound. (orig.)

Mammography-oncogenecity at low doses

International Nuclear Information System (INIS)

Heyes, G J; Mill, A J; Charles, M W

2009-01-01

Controversy exists regarding the biological effectiveness of low energy x-rays used for mammography breast screening. Recent radiobiology studies have provided compelling evidence that these low energy x-rays may be 4.42 ± 2.02 times more effective in causing mutational damage than higher energy x-rays. These data include a study involving in vitro irradiation of a human cell line using a mammography x-ray source and a high energy source which matches the spectrum of radiation observed in survivors from the Hiroshima atomic bomb. Current radiation risk estimates rely heavily on data from the atomic bomb survivors, and a direct comparison between the diagnostic energies used in the UK breast screening programme and those used for risk estimates can now be made. Evidence highlighting the increase in relative biological effectiveness (RBE) of mammography x-rays to a range of x-ray energies implies that the risks of radiation-induced breast cancers for mammography x-rays are potentially underestimated by a factor of four. A pooled analysis of three measurements gives a maximal RBE (for malignant transformation of human cells in vitro) of 4.02 ± 0.72 for 29 kVp (peak accelerating voltage) x-rays compared to high energy electrons and higher energy x-rays. For the majority of women in the UK NHS breast screening programme, it is shown that the benefit safely exceeds the risk of possible cancer induction even when this higher biological effectiveness factor is applied. The risk/benefit analysis, however, implies the need for caution for women screened under the age of 50, and particularly for those with a family history (and therefore a likely genetic susceptibility) of breast cancer. In vitro radiobiological data are generally acquired at high doses, and there are different extrapolation mechanisms to the low doses seen clinically. Recent low dose in vitro data have indicated a potential suppressive effect at very low dose rates and doses. Whilst mammography is a low

Drywall plates evaluation as protection barriers in dental X-rays and mammography facilities

International Nuclear Information System (INIS)

Guevara R, V. Y.; Romero C, N.; Berrocal T, M.

2014-08-01

In the dental X-rays and mammography facilities, usually lead shielded walls as protective barriers are used. Lead is a good attenuator for X-rays, but has toxic properties and its cost is high. Mammography equipment s emit low-energy photons in the range of 25 keV to 35 keV, on current computers; the primary radiation beam is intercepted by the image receptor. Peri apical dental equipment s emit photons in the range of 50 to 90 keV, their filtration is fixed. These devices emit a collimated beam whose diameter is slightly larger than the diagonal dimension of a standard film of dental X-rays. When a dental x-ray is performed, the radiation beam is partially attenuated by the patient. Drywall is a material consisting of plasterboard between two cardboard layers, being its components gypsum and cellulose generally. It is used in construction for execution of interior walls, ceilings and wall coverings, could also serve as a replacement for lead as well as other materials. In this paper three drywall prototypes (Giplac), formed with 02, 04 and 06 drywall layers (13, 16 and 20 cm of thickness respectively) were tested as barriers against primary and secondary X-ray radiation that come from dental and mammography equipment s. The results show that the drywall prototype, 02 layers, efficiently attenuates the secondary radiation beam produced by conventional mammography equipment. And the prototype 04 and 06 layers, efficiently attenuates the primary radiation beam produced by peri apical dental equipment. (author)

Combination of one-view digital breast tomosynthesis with one-view digital mammography versus standard two-view digital mammography: per lesion analysis

Energy Technology Data Exchange (ETDEWEB)

Gennaro, Gisella; Bezzon, Elisabetta; Pescarini, Luigi; Polico, Ilaria; Proietti, Alessandro; Baldan, Enrica; Pomerri, Fabio; Muzzio, Pier Carlo [Veneto Institute of Oncology (IRCCS), Padua (Italy); Hendrick, R.E. [University of Colorado-Denver, Department of Radiology, School of Medicine, Aurora, CO (United States); Toledano, Alicia [Biostatistics Consulting, LLC, Kensington, MD (United States); Paquelet, Jean R. [Advanced Medical Imaging Consultants, Fort Collins, CO (United States); Breast Imaging, McKee Medical Center, Loveland, CO (United States); Chersevani, Roberta [Private Medical Practice, Gorizia (Italy); Di Maggio, Cosimo [Private Medical Practice, Padua (Italy); La Grassa, Manuela [Department of Radiology, Oncological Reference Center (IRCCS), Aviano (Italy)

2013-08-15

To evaluate the clinical value of combining one-view mammography (cranio-caudal, CC) with the complementary view tomosynthesis (mediolateral-oblique, MLO) in comparison to standard two-view mammography (MX) in terms of both lesion detection and characterization. A free-response receiver operating characteristic (FROC) experiment was conducted independently by six breast radiologists, obtaining data from 463 breasts of 250 patients. Differences in mean lesion detection fraction (LDF) and mean lesion characterization fraction (LCF) were analysed by analysis of variance (ANOVA) to compare clinical performance of the combination of techniques to standard two-view digital mammography. The 463 cases (breasts) reviewed included 258 with one to three lesions each, and 205 with no lesions. The 258 cases with lesions included 77 cancers in 68 breasts and 271 benign lesions to give a total of 348 proven lesions. The combination, DBT{sub (MLO)}+MX{sub (CC)}, was superior to MX (CC+MLO) in both lesion detection (LDF) and lesion characterization (LCF) overall and for benign lesions. DBT{sub (MLO)}+MX{sub (CC)} was non-inferior to two-view MX for malignant lesions. This study shows that readers' capabilities in detecting and characterizing breast lesions are improved by combining single-view digital breast tomosynthesis and single-view mammography compared to two-view digital mammography. (orig.)

Current perspectives on indications and limitations of mammography

International Nuclear Information System (INIS)

Pope, T.L. Jr.

1983-01-01

Women have a 7 percent natural lifetime risk of developing breast cancer, which is the leading cause of death in women aged 40 to 50 years. Most data suggest that the earlier the disease is diagnosed, the better the chance for cure. Women with ''minimal breast cancer'' have an actuarial 20-year survival rate of 93.2 percent. The majority of these breast cancers are diagnosed by mammography. The radiation doses from this technique have been dramatically decreased over the last ten years to about 0.1 to 0.6 rads per study. The two largest breast cancer screening studies, the Health Insurance Plan of Greater New York and the Breast Cancer Detection Demonstration Project, have shown conclusively that women over 50 years old can benefit from annual mammography and that certain groups can benefit from mammography at close intervals before the age of 50 years. This article describes the development of mammography and outlines current perspectives on its indications and limitations

Influence of the radiographer on the pain felt during mammography

International Nuclear Information System (INIS)

Goethem, M. van; Verslegers, I.; Biltjes, I.; De Schepper, A.; Mortelmans, D.; Bruyninckx, E.; Hove, E. Van

2003-01-01

Mammography is the only useful examination in screening for breast cancer. Mortality from breast cancer can be reduced if women go regularly for a screening mammography. Moreover, it is still the key examination in diagnosis of breast diseases and in the follow-up of patients treated for breast cancer. Pain with mammography can deter women from going for regular screening or follow-up; therefore, it is important to reduce pain experience or discomfort from mammography. In this study we evaluate the impact of the ''radiographer'' on the pain risk during mammography by analysing questionnaires filled in by women and radiographers. Study results reveal that the opinion of the radiographer, the information and communication during the examination and the number of years of experience are important factors in pain and discomfort experience. The attitude of the radiographer plays an important role in the pain experience. (orig.)

Current status of mammography

International Nuclear Information System (INIS)

Crymes, J.E.

1979-01-01

Great progress has been made in recent years in the diagnosis and treatment of breast cancer; however, breast cancer continues to be the most common and lethal cancer in women today. Early diagnosis is essential in order for treatmet to be given before the tumor spreads beyond the breast. The radiation risks of mammography have been greatly reduced with the use of newer low-dose techniques, and the benefits of mammography have increased because of a better understanding of the natural history of breast cancer, as well as improved methods of treatment. Radiologists must continue to take an active role in the early diagnosis of breast cancer. Continued research is needed in order to improve screening methods and to develop newer, noninvasive techniques

A conversion method of air kerma from the primary, scatter, and leakage radiations to effective dose for calculating x-ray shielding barriers in mammography

International Nuclear Information System (INIS)

Kharrati, Hedi

2005-01-01

In this study, a new approach has been introduced for derivation of the effective dose from air kerma to calculate shielding requirements in mammography facilities. This new approach has been used to compute the conversion coefficients relating air kerma to the effective dose for the mammography reference beam series of the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency laboratories. The results show that, in all cases, the effective dose in mammography energy range is less than 25% of the incident air kerma for the primary and the scatter radiations and does not exceed 75% for the leakage radiation

Evaluation of the performance characteristic for mammography by using edge device

Energy Technology Data Exchange (ETDEWEB)

Kim, Ki Won [Dept. of Radiology, Kyung Hee University Hospital at Gang-dong, Seoul (Korea, Republic of); Choi, Jwan Woo [Dept. of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Jeong, Hoi Woun [Dept. of Radiological Technology, The Baekseok Culture University, Cheonan (Korea, Republic of); Jang, Seo Goo [Dept. of Medical Science, The Soonchunhyang University, Asan (Korea, Republic of); Lee, Eul Kyu [Dept. of Radiology, Inje Paik University Hospital Jeo-dong, Seoul (Korea, Republic of); Son, Soon Yong [Dept. of Radiological Technology, The Wonkwang Health Science University, Iksan (Korea, Republic of); Son, Jin Hyun; Min, Jung Whan [Dept. of Radiological Technology, The Shingu University, Sungnam (Korea, Republic of)

2016-09-15

The purpose of this study was to evaluation of the performance characteristic for mammography by using edge device that mammography equipment improves essential in the correct diagnosis for the maintenance. We measured the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) using the 61267 RQA-M2 based on commission standard international electro-technical commission (IEC). As a results, spatial resolution of dimensions tomo and lorad selenia mammography were maintained at 10 mm-1 and NPS and DQE including the low nyquist frequency indicated to 6.0 mm-1. Therefore, regularly QA of mammography system should be necessary. This study can be contribute to evaluate QA for performance characteristic of mammography of DDR system.

The effects of induced oblique astigmatism on symptoms and reading performance while viewing a computer screen.

Science.gov (United States)

Rosenfield, Mark; Hue, Jennifer E; Huang, Rae R; Bababekova, Yuliya

2012-03-01

Computer vision syndrome (CVS) is a complex of eye and vision problems related to computer use which has been reported in up to 90% of computer users. Ocular symptoms may include asthenopia, accommodative and vergence difficulties and dry eye. Previous studies have reported that uncorrected astigmatism may have a significant impact on symptoms of CVS. However, its effect on task performance is unclear. This study recorded symptoms after a 10 min period of reading from a computer monitor either through the habitual distance refractive correction or with a supplementary -1.00 or -2.00D oblique cylinder added over these lenses in 12 young, visually-normal subjects. Additionally, the distance correction condition was repeated to assess the repeatability of the symptom questionnaire. Subjects' reading speed and accuracy were monitored during the course of the 10 min trial. There was no significant difference in reading rate or the number of errors between the three astigmatic conditions. However, a significant change in symptoms was reported with the median total symptom scores for the 0, 1 and 2D astigmatic conditions being 2.0, 6.5 and 40.0, respectively (p computer operation. Ophthalmic & Physiological Optics © 2011 The College of Optometrists.

Calibration procedures for mammography dosemeters in Poland

International Nuclear Information System (INIS)

Gwiazdowska, B.; Ulkowski, P.; Tolwinski, J.; Bulski, W.

2002-01-01

Breast cancer is the most frequent tumour in women and the effectiveness of the treatment depends dramatically on the early detection of the disease. That is the reason why in Poland the mammography control examinations are strongly supported by the Centre of Oncology. In Poland there are over 400 mammography units which account for about 300,000 examinations per year. An investigation performed by the Medical Physics Department of the Centre of Oncology in Warsaw at about 100 mammography facilities proved that in most cases the doses absorbed by the patients could be reduced without decrease of image quality. This is one of the reasons why the Polish Secondary Standard Dosimetry Laboratory (SSDL) dealing mainly with calibration of radiotherapy dosemeters is extending its activities and therefore new facilities and equipment adapted for calibration of mammographic dosemeters have been installed. The mammography dosimetry calibration equipment is permanently installed in the same laboratory room where the radiotherapy dosemeters are calibrated. A base of a mammography unit no longer in clinical use, together with its movable system has been adapted to handle ionization chamber holders. An X-ray tube with a 50 kV high frequency generator was also installed. The tube, a Varian type OEG-50-2, (designed for laboratory applications) with molybdenum anode of an anode angle 23,7 deg. and with a large focus, effective size approximately 5 mm 2 , has an inherent filtration of 0,25 mm beryllium. It is installed in a housing with 2mm lead shielding; a cone shaped beam is formed by a system of three collimators

Tests with films and film-screens using grid-mammography

International Nuclear Information System (INIS)

Wolf, G.; Kallinger, G.

1982-01-01

A comparison was made between mammography using grid-technique with a film-screen-system and mammography without grid, and with film-screens and also using industrial films. The image-quality of grid mammography looks like the same than using conventional techniques and industrial films. The problem of soft tissue grid techniques lies in the dose requirements, which was more than using film-screen-techniques without grid. New and improved recording systems, which reduce radiation dose when using the grid technique were analyzed. (orig.) [de

Benefits of the quality assured double and arbitration reading of mammograms in the early diagnosis of breast cancer in symptomatic women

International Nuclear Information System (INIS)

Waldmann, Annika; Katalinic, Alexander; Kapsimalakou, Smaragda; Grande-Nagel, Isabell; Barkhausen, Joerg; Vogt, Florian M.; Stoeckelhuber, Beate M.; Fischer, Dorothea

2012-01-01

To address the benefits of double and arbitration reading regarding tumour detection rates, percentage of in situ tumours, and number (of patients) needed to send for expert reading (number needed to treat; NNT) for one additional tumour finding. QuaMaDi is a quality assured breast cancer diagnosis programme; with two-view mammography (craniocaudal, mediolateral oblique) and, in case of breast density ACR 3 or 4, routine ultrasound imaging; and with independent double reading of all images. A consecutive sample of symptomatic women, i.e. women at risk for breast cancer, women aged 70 and above, and/or women with preceding BI-RADS III findings, was analysed. 28,558 mammograms were performed (mean age of women: 57.3 [standard deviation: 12.3] years). Discordant findings were present in 3,837 double readings and were sent for arbitration reading. After histopathological assessment, 52 carcinomas were found (thereof 32% in situ). These carcinomas accounted for 1.8 tumours per 1,000 examinations in the total cohort and increased the tumour detection rate up to 16.4/1,000. The NNT in discordant cases was 74. Double and arbitration reading appears to be a useful tool to ensure the quality of early detection of breast lesions in symptomatic women during indication-based, standardised mammography. circle Quality assured breast cancer diagnosis is feasible outside organised screening structures. (orig.)

Computer-aided diagnosis of contrast-enhanced spectral mammography: A feasibility study.

Science.gov (United States)

Patel, Bhavika K; Ranjbar, Sara; Wu, Teresa; Pockaj, Barbara A; Li, Jing; Zhang, Nan; Lobbes, Mark; Zhang, Bin; Mitchell, J Ross

2018-01-01

To evaluate whether the use of a computer-aided diagnosis-contrast-enhanced spectral mammography (CAD-CESM) tool can further increase the diagnostic performance of CESM compared with that of experienced radiologists. This IRB-approved retrospective study analyzed 50 lesions described on CESM from August 2014 to December 2015. Histopathologic analyses, used as the criterion standard, revealed 24 benign and 26 malignant lesions. An expert breast radiologist manually outlined lesion boundaries on the different views. A set of morphologic and textural features were then extracted from the low-energy and recombined images. Machine-learning algorithms with feature selection were used along with statistical analysis to reduce, select, and combine features. Selected features were then used to construct a predictive model using a support vector machine (SVM) classification method in a leave-one-out-cross-validation approach. The classification performance was compared against the diagnostic predictions of 2 breast radiologists with access to the same CESM cases. Based on the SVM classification, CAD-CESM correctly identified 45 of 50 lesions in the cohort, resulting in an overall accuracy of 90%. The detection rate for the malignant group was 88% (3 false-negative cases) and 92% for the benign group (2 false-positive cases). Compared with the model, radiologist 1 had an overall accuracy of 78% and a detection rate of 92% (2 false-negative cases) for the malignant group and 62% (10 false-positive cases) for the benign group. Radiologist 2 had an overall accuracy of 86% and a detection rate of 100% for the malignant group and 71% (8 false-positive cases) for the benign group. The results of our feasibility study suggest that a CAD-CESM tool can provide complementary information to radiologists, mainly by reducing the number of false-positive findings. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical utility of scintimammography: From the Anger-camera to new dedicated devices

Energy Technology Data Exchange (ETDEWEB)

Schillaci, Orazio [Department of Biopathology and Diagnostic Imaging, University ' Tor Vergata' , Viale G. Mazzini 121, 00195 Rome (Italy)]. E-mail: oschil@tiscali.it; Danieli, Roberta [Department of Biopathology and Diagnostic Imaging, University ' Tor Vergata' , Viale G. Mazzini 121, 00195 Rome (Italy); Romano, Pasquale [Department of Biopathology and Diagnostic Imaging, University ' Tor Vergata' , Viale G. Mazzini 121, 00195 Rome (Italy); Cossu, Elsa [Department of Biopathology and Diagnostic Imaging, University ' Tor Vergata' , Viale G. Mazzini 121, 00195 Rome (Italy); Simonetti, Giovanni [Department of Biopathology and Diagnostic Imaging, University ' Tor Vergata' , Viale G. Mazzini 121, 00195 Rome (Italy)

2006-12-20

Scintimammography is a functional imaging technique which uses a radiation detection camera to detect radionuclide tracers in the patient's breasts. Tracers are designed to accumulate in tumours more than in healthy tissue: the most used are Tc-99 m sestamibi and Tc-99 m tetrofosmin. Scintimammography is useful in some clinical indications as an adjunct to mammography: it is recommended for those lesions where additional information is required to reach a definitive diagnosis. Patients with dubious mammograms may benefit from this test, as well as women with dense breasts or with implants. Scintimammography is a valuable diagnostic tool also in patients with locally advanced breast cancer for monitoring and predicting response to neoadjuvant chemotherapy. Nevertheless, using an Anger-camera this technique shows a high sensitivity only for cancers >1 cm. Since other modalities are increasingly employed for the early identification of small abnormalities, the issue of detecting small cancers is critical for the future development and clinical utility of breast imaging with radiopharmaceuticals. The use of high-resolution cameras dedicated for breast imaging is the best option to improve the detection of small cancers: they allow higher flexibility in patient positioning, and the availability of mammography-like projections. Moreover, the detector can be placed directly in contact with the breast allowing a mild compression with reduction of the breast's thickness, thus increasing the target-to-background ratio and the sensitivity. These new devices have the potential of increasing the total number of breast scintigraphies performed thereby enhancing the role of nuclear medicine in breast cancer imaging.

Pain during mammography: Implications for breast screening programmes

International Nuclear Information System (INIS)

Andrews, F.J.

2001-01-01

Pain experienced during mammography can deter women from attending for breast cancer screening. Review of the current literature on pain experienced during mammography reveals three main areas of interest: reports of the frequency of pain, identification of predictors of pain and strategies for responding to pain. Implications of this literature for breast screening programmes include the need for appropriate measurements of pain during mammography that are valid for screening populations, a further understanding of organizational factors involved in screening programmes that may be predictors of pain and for the development of valid strategies for responding to pain within breast screening programmes. Copyright (2001) Blackwell Science Pty Ltd

What Does Research on Computer-Based Instruction Have to Say to the Reading Teacher?

Science.gov (United States)

Balajthy, Ernest

1987-01-01

Examines questions typically asked about the effectiveness of computer-based reading instruction, suggesting that these questions must be refined to provide meaningful insight into the issues involved. Describes several critical problems with existing research and presents overviews of research on the effects of computer-based instruction on…

Hardware for mammography

International Nuclear Information System (INIS)

Rozhkova, N.I.; Chikirdin, Eh.G.; Ryudiger, Yu.G.; Kochetova, G.P.; Lisachenko, I.V.; Yakobs, O.Eh.

2000-01-01

The comparative studies on various visualization means, in particular, the intensifying screens and films with application of quantitative methods for determining small details on photographs, including measurements of corresponding exposures, absorbed doses and verification of conclusions through the analysis of clinical observations are carried out. It is shown, that technical equipment of the modern mammography room should include the X-ray mammographic apparatus, providing for the image high-quality by low dose loads with special film holders, meeting the mammography requirements, the corresponding X-ray film and the automatic photolaboratory process, provided by one and the same company. The quality of photographs under such conditions is guarantied, the defects and errors by the image interpretation are excluded. The modern computerized information technologies for work with medical images on the basic of creating new generations of diagnostic instrumentation with digital video channels and computerized working places dispose of many medical, technological, organizational and financial problems [ru

Micro calcification evaluation using CR plates in computerized mammography

International Nuclear Information System (INIS)

Bustos F, M.; Prata M, A.

2017-10-01

Cancer is one of the leading causes of mortality in the world. In 2012, about 14 million new cases were registered, of which 1.6 million are breast cancer, according to the World Health Organization. The National Cancer Institute of Brazil estimated 57 thousand new cases of breast cancer by 2016. Mammography is the imaging technique most used worldwide for the early diagnosis of breast cancer. Computed radiography (CR) plates are used for digital radiography, and are widely used to obtain digital mammograms. This work aims to evaluate te response of CR plates to the variation of exposure in mammography equipment. Three CR plates for mammography of different models were used for the study. X-ray beams were selected to perform successive exposures of CR plates by varying the exposure time. These exposures were performed to obtain raw images that were subsequently analyzed using ImageJ software, from which the value of intensity recorded in the central region of each image was obtained, correlating it with the exposure time. From these data the necessary correlations were made to determine the exposure time for which the CR plate begins to saturate, observing that the saturation occurs first for the highest value of the applied voltage. Finally, successive exposures of the CR plate were made using the compressed breast simulator made of acrylic plates and containing microcalcifications of different sizes to determine the qualitative resolution of CR plates, observing that only microcalcifications above 177 μm are visible in the image. The knowledge of saturation characteristics and resolution of the CR plate allows the selection of more adequate parameters to work without approaching the saturation region. (Author)

Micro calcification evaluation using CR plates in computerized mammography

Energy Technology Data Exchange (ETDEWEB)

Bustos F, M.; Prata M, A., E-mail: mabelita.bfm@gmail.com [Federal University of Minas Gerais, School of Engineering, Department of Nuclear Engineering, Av. Antonio Carlos CEP 131270-901 Belo Horizonte, Minas Gerais (Brazil)

2017-10-15

Cancer is one of the leading causes of mortality in the world. In 2012, about 14 million new cases were registered, of which 1.6 million are breast cancer, according to the World Health Organization. The National Cancer Institute of Brazil estimated 57 thousand new cases of breast cancer by 2016. Mammography is the imaging technique most used worldwide for the early diagnosis of breast cancer. Computed radiography (CR) plates are used for digital radiography, and are widely used to obtain digital mammograms. This work aims to evaluate te response of CR plates to the variation of exposure in mammography equipment. Three CR plates for mammography of different models were used for the study. X-ray beams were selected to perform successive exposures of CR plates by varying the exposure time. These exposures were performed to obtain raw images that were subsequently analyzed using ImageJ software, from which the value of intensity recorded in the central region of each image was obtained, correlating it with the exposure time. From these data the necessary correlations were made to determine the exposure time for which the CR plate begins to saturate, observing that the saturation occurs first for the highest value of the applied voltage. Finally, successive exposures of the CR plate were made using the compressed breast simulator made of acrylic plates and containing microcalcifications of different sizes to determine the qualitative resolution of CR plates, observing that only microcalcifications above 177 μm are visible in the image. The knowledge of saturation characteristics and resolution of the CR plate allows the selection of more adequate parameters to work without approaching the saturation region. (Author)

The clinical use of mammography in the male; Klinische Relevanz der Mammographie beim Mann

Energy Technology Data Exchange (ETDEWEB)

Merkle, E [Ulm Univ. (Germany). Abt. Radiologie; Mueller, M [Ulm Univ. (Germany). Abt. Radiologie; Vogel, J [Ulm Univ. (Germany). Abt. Radiologie; Klatt, S [Ulm Univ. (Germany). Abt. Innere Medizin I; Goerich, J [Ulm Univ. (Germany). Abt. Radiologie; Berger, H G [Ulm Univ. (Germany). Allgemeinchirurgische Abt.; Brambs, H J [Ulm Univ. (Germany). Abt. Radiologie

1996-01-01

During a period of four years 104 mammograms were performed in 89 men. Mastectomies were carried out on 23 men (group 1). 66 patients (group 2) were followed up clinically and in 15 patients serial mammograms were obtained. In group 1 there were 5 patients with bilateral gynaecomastia, 9 with unilateral gynaecomastia and two with pseudogynaecomastia and there were 7 patients with malignancies. In group 2 there were 46 patients with bilateral gynaecomastia and 10 patients with unilateral gynaecomastia. Pseudogynaecomastia was found in 25 patients. There were 7 malignancies, of which 5 had been suspected clinically and one had been diagnosed as gynaecomastia by mammography. Two carcinomas in situ were missed clinically and also by mammography. When malignancy is not suspected on clinical grounds the first examination should be sonography. Where, however, malignancy is suspected, and for follow-up, mammography retains its primary position. (orig./MG) [Deutsch] In einem 4-Jahres-Zeitraum wurden bei 89 Maennern insgesamt 104 Mammogramme angefertigt. 23 Maenner (=Gruppe 1) wurden mastektomiert. 66 Patienten (=Gruppe 2) wurden klinisch und zum Teil mammographisch kontrolliert. Alle Mammogramme wurden in Unkenntnis des klinischen Befundes retrospektiv ausgewertet und, wenn moeglich, dem histologischen Ergebnis gegenuebergestellt. In der Gruppe 1 fand sich eine beidseitige Gynaekomastie in 5/23 Faellen, eine einseitige Form in 9/23 Faellen, eine Pseudogynaekomastie in 2/23 Faellen und ein Malignom in 7/23 Faellen. In Gruppe 2 ergab sich eine beidseitige Gynaekomastie in 46/81 Faellen gegenueber einer einseitigen Form in 10/81 Faellen. Eine Pseudogynaekomastie fand sich in 25/81 Faellen. Von 7 Malignomen waren 5 klinisch suspekt, wobei eines mammographisch als Gynaekomastie imponierte. Zwei In-situ-Karzinome waren sowohl mammographisch als auch klinisch okkult. Klinisch nicht malignomsuspekte Befunde sollten primaer der Mammasonographie zugefuehrt werden. Bei

Breast Cancer Detection: Mammography and other methods in breast imaging, second edition

International Nuclear Information System (INIS)

Bassett, L.W.; Gold, R.H.

1987-01-01

The text addresses mammography and the advantages and limitations of other breast imaging methods presently available. The establishment of X-ray mammography as the safest and most accurate noninvasive method of early, nonpalpable breast cancer detection is addressed in the first section of the book. The second section emphasizes the signs of early cancer, the complete mammographic examination, and the team approach to diagnosis. The advantages and limitations of film-screen mammography, zero mammography, breast ultrasound, thermography, light scanning, magnetic resonance imaging, and ductography are highlighted as alternate methods of detection. The benefits of mammography, and its unmatched value in screeening for breast cancer, are presented in the final section

Radiation dose with digital breast tomosynthesis compared to digital mammography: per-view analysis.

Science.gov (United States)

Gennaro, Gisella; Bernardi, D; Houssami, N

2018-02-01

To compare radiation dose delivered by digital mammography (FFDM) and breast tomosynthesis (DBT) for a single view. 4,780 FFDM and 4,798 DBT images from 1,208 women enrolled in a screening trial were used to ground dose comparison. Raw images were processed by an automatic software to determine volumetric breast density (VBD) and were used together with exposure data to compute the mean glandular dose (MGD) according to Dance's model. DBT and FFDM were compared in terms of operation of the automatic exposure control (AEC) and MGD level. Statistically significant differences were found between FFDM and DBT MGDs for all views (CC: MGD FFDM =1.366 mGy, MGD DBT =1.858 mGy; ptomosynthesis compared to FFDM. Given the emerging role of DBT, its use in conjunction with synthetic 2D images should not be deterred by concerns regarding radiation burden, and should draw on evidence of potential clinical benefit. • Most studies compared tomosynthesis in combination with mammography vs. mammography alone. • There is some concern about the dose increase with tomosynthesis. • Clinical data show a small increase in radiation dose with tomosynthesis. • Synthetic 2D images from tomosynthesis at zero dose reduce potential harm. • The small dose increase should not be a barrier to use of tomosynthesis.

Response costs of mammography adherence: Iranian women's perceptions.

Science.gov (United States)

Khodayarian, Mahsa; Mazloomi-Mahmoodabad, Seyed Saied; Lamyian, Minoor; Morowatisharifabad, Mohammad Ali; Tavangar, Hossein

2016-01-01

Mammography as the most common secondary prevention method has known to be helpful in detecting breast cancer at the early stages. Low level of participation among women toward mammography uptake due to cultural beliefs is a great concern. This study aimed at exploring the perceptions of women about response costs of mammography adherence (MA) in Yazd, Iran. A qualitative study using semi-structured interviews was performed. Fourteen women,one oncology nurse, and a breast cancer survivor were purposefully interviewed. Interviews were transcribed verbatim and analyzed by directed content analysis method based on protection motivation theory (PMT). One main theme was emerged from the analysis namely called "response costs".Two main categories were also emerged from the data; (1) psychological barriers with six subcategories including "embarrassment," "worry about being diagnosed with cancer," "preoccupation with underlying disease," "misconception about mammography," "need for an accompanying person," and "internalizing the experiences of the others," and (2) maladaptive coping modes which encompassed three subcategories: "religious faith," "fatalism," and"avoidance and denial." Useful information was provided about the response costs of mammography utilization based on the perceptions of women. Cognitive barriers may be decreased by conducting modifications in women's awareness and attitude toward MA as well as changing the national health system infrastructures. Incorporating religious and cultural belief systems into MA educational programs through motivational messages is recommended.

Study of mammography in mass screening for breast cancer

International Nuclear Information System (INIS)

Kitada, Masahiro; Sakai, Hiroko; Kubo, Yoshihiko; Samejima, Natsuki; Kurowarabi, Kunio; Iwabuchi, Shuji.

1995-01-01

In order to examine the rate of correct diagnosis by mammography at initial mass screening for breast cancer, we carried out a retrospective study of mammography findings in 267 cases of breast cancer detected at Asahikawa Cancer Screening Center. The screening was performed by physical examination, and in cases where disease was suspected, mammography, ultrasonography, and needle biopsy were done. Mammographically, 172 cases (64.4%) were cancer-positive, 58 cases (21.7%) were suspicious for cancer, and 37 cases (13.9%) were cancer-negative. Patients below 50 years of age and those with tumors of small diameter (<20 mm) showed a significantly lower rate of cancer positivity than patients aged 50 years or more and those with tumors 20 mm or more in diameter. Mammographic abnormalities were not specific, since these changes were also found in normal subjects and patients with benign diseases. Therefore, we concluded that mammography without physical examination at initial mass screening has a high risk of missing breast cancer. Mass screening for breast cancer should be performed by physical examination involving inspection and palpation at the first instance. If any suspicious findings are obtained, mammography, ultrasonography, and needle biopsy should be done. (author)

Differential Effects of Social Networks on Mammography Use by Poverty Status.

Science.gov (United States)

Yeo, Younsook

2016-01-01

This study examines whether social networks have differential effects on mammography use depending on poverty status. Data were analyzed on US women (40+), employing logistic regression and simple slope analyses for a post hoc probing of moderating effects. Among women not in poverty, living with a spouse/partner and attending church, regardless of frequency, were positively associated with mammography use; family size was negatively associated. Among women living in poverty, mammography showed a positive association only with weekly church attendance. Mammography was negatively associated with health-related social interactions occurring through the Internet. Post hoc probing showed significant moderating effects of poverty on the relationship between online health-related interactions and mammography use. To make the Internet a meaningful health empowerment tool for women in poverty, future research should identify how health-related interactions that occur online affect women in poverty's psychological and behavioral reactions that will contribute to our understanding of why they are discouraged from having mammograms. The mechanisms behind the differential effects of church attendance and poverty status on mammography also need further clarification.

Phosphor plate mammography: contrast studies and clinical experience

International Nuclear Information System (INIS)

Chang, C.H.J.; Martin, N.L.; Templeton, A.W.; Cook, L.T.; Harrison, L.A.; McFadden, M.A.; Dwyer, S.J. III; Spicer, J.; Crystal, J.M.

1992-01-01

Mammography and accurate microcalcification detection require very good spatial resolution. We have compared the diagnostic capabilities of reduced-exposure, third-generation, 5 cycles/mm computed radiography (CR) phosphor plates with conventional screen-film in 67 patients. No difference in diagnostic accuracy was detected. The digital characteristics of storage phosphor plates erabled us to study the relationship between contrast and spatial resolution. We developed a computer program to identify a single 100 μm pixel in a digital image and assign various gray levels to that pixel. Using this model, we determined that, for our 5 cycles/mm CR system, the imaged contrast of a 100 μm object was 62% of the original contrast. Current 5 cycles/mm phosphor plate systems cannot adequately detect microcalcifications that approximate 100 μm or smaller unless a magnification technique is used. (orig.)

WE-FG-207A-05: Dedicated Breast CT as a Diagnostic Imaging Tool: Physics and Clinical Feasibility

International Nuclear Information System (INIS)

Karellas, A.

2016-01-01

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

WE-FG-207A-05: Dedicated Breast CT as a Diagnostic Imaging Tool: Physics and Clinical Feasibility

Energy Technology Data Exchange (ETDEWEB)

Karellas, A. [University of Massachusetts Medical School (United States)

2016-06-15

Mammography-based screening has been a valuable imaging tool for the early detection of non-palpable lesions and has contributed to significant reduction in breast cancer associated mortality. However, the breast imaging community recognizes that mammography is not ideal, and in particular is inferior for women with dense breasts. Also, the 2-D projection of a 3-D organ results in tissue superposition contributing to false-positives. The sensitivity of mammography is breast-density dependent. Its sensitivity, especially in dense breasts, is low due to overlapping tissue and the fact that normal breast tissue, benign lesions and breast cancers all have similar “densities”, making lesion detection more difficult. We ideally need 3-D imaging for imaging the 3-D breast. MRI is 3-D, whole breast ultrasound is 3-D, digital breast tomosynthesis is called 3-D but is really “pseudo 3-D” due to poor resolution along the depth-direction. Also, and importantly, we need to be able to administer intravenous contrast agents for optimal imaging, similar to other organ systems in the body. Dedicated breast CT allows for 3-D imaging of the uncompressed breast. In current designs, the patient is positioned prone on the table and the breast is pendant through an aperture and the scan takes approximately 10 seconds [O’Connell et al., AJR 195: 496–509, 2010]. Almost on the heels of the invention of CT itself, work began on the development of dedicated breast CT. These early breast CT systems were used in clinical trials and the results from comparative performance evaluation of breast CT and mammography for 1625 subjects were reported in 1980 [Chang et al., Cancer 46: 939–46, 1980]. However, the technological limitations at that time stymied clinical translation for decades. Subsequent to the landmark article in 2001 [Boone et al., Radiology 221: 657–67, 2001] that demonstrated the potential feasibility in terms of radiation dose, multiple research groups are actively

At what age should screening mammography be recommended for Asian women?

International Nuclear Information System (INIS)

Tsuchida, Junko; Nagahashi, Masayuki; Rashid, Omar M; Takabe, Kazuaki; Wakai, Toshifumi

2015-01-01

Although regular screening mammography has been suggested to be associated with improvements in the relative survival of breast cancer in recent years, the appropriate age to start screening mammography remains controversial. In November 2009, the United States Preventive Service Task Force published updated guidelines for breast cancer, which no longer support routine screening mammography for women aged 40–49 years, but instead, defer the choice of screening in that age group to the patient and physician. The age to begin screening differs between guidelines, including those from the Task Force, the American Cancer Society and the World Health Organization. It remains unclear how this discrepancy impacts patient survival, especially among certain subpopulations. Although the biological characteristics of breast cancer and peak age of incidence differ among different ethnic populations, there have been few reports that evaluate the starting age for screening mammography based on ethnicity. Here, we discuss the benefits and harm of screening mammography in the fifth decade, and re-evaluate the starting age for screening mammography taking ethnicity into account, focusing on the Asian population. Breast cancer incidence peaked in the fifth decade in Asian women, which has been thought to be due to a combination of biological and environmental factors. Previous reports suggest that Asian women in their 40s may receive more benefit and less harm from screening mammography than the age-matched non-Asian US population. Therefore, starting screening mammography at age 40 may be beneficial for women of Asian ethnicity in well-resourced countries, such as Japanese women who reside in Japan

Cone-Beam CT Angiography for Determination of Tumor-Feeding Vessels During Chemoembolization of Liver Tumors: Comparison of Conventional and Dedicated-Software Analysis.

Science.gov (United States)

Ronot, Maxime; Abdel-Rehim, Mohamed; Hakimé, Antoine; Kuoch, Viseth; Roux, Marion; Chiaradia, Mélanie; Vilgrain, Valérie; de Baere, Thierry; Deschamps, Frédéric

2016-01-01

To compare the ability of dedicated software and conventional cone-beam computed tomography (CT) analysis to identify tumor-feeding vessels in hypervascular liver tumors treated with chemoembolization. Between January 2012 and January 2013, 45 patients (32 men, mean age of 61 y; range, 27-85 y) were enrolled, and 66 tumors were treated (mean, 32 mm ± 18; range, 10-81 mm) with conventional chemoembolization with arterial cone-beam CT. Data were independently analyzed by six interventional radiologists with standard postprocessing software, a computer-aided analysis with FlightPlan for liver (FPFL; ie, "raw FPFL"), and a review of this computer-aided FPFL analysis ("reviewed FPFL"). Analyses were compared with a reference reading established by two study supervisors in consensus who had access to all imaging data. Sensitivities, positive predictive values (PPVs), and false-positive (FP) ratios were compared by McNemar, χ(2), and Fisher exact tests. Analysis durations were compared by Mann-Whitney test, and interreader agreement was assessed. Reference reading identified 179 feeder vessels. The sensitivity of raw FPFL was significantly higher than those of reviewed FPFL and conventional analyses (90.9% vs 83.2% and 82.1%; P software enabled a fast, accurate, and sensitive detection of tumor feeder vessels. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

The Locus of Serial Processing in Reading Aloud: Orthography-to-Phonology Computation or Speech Planning?

Science.gov (United States)

Mousikou, Petroula; Rastle, Kathleen; Besner, Derek; Coltheart, Max

2015-01-01

Dual-route theories of reading posit that a sublexical reading mechanism that operates serially and from left to right is involved in the orthography-to-phonology computation. These theories attribute the masked onset priming effect (MOPE) and the phonological Stroop effect (PSE) to the serial left-to-right operation of this mechanism. However,…

Development of a methodology for automated assessment of the quality of digitized images in mammography

International Nuclear Information System (INIS)

Santana, Priscila do Carmo

2010-01-01

The process of evaluating the quality of radiographic images in general, and mammography in particular, can be much more accurate, practical and fast with the help of computer analysis tools. The purpose of this study is to develop a computational methodology to automate the process of assessing the quality of mammography images through techniques of digital imaging processing (PDI), using an existing image processing environment (ImageJ). With the application of PDI techniques was possible to extract geometric and radiometric characteristics of the images evaluated. The evaluated parameters include spatial resolution, high-contrast detail, low contrast threshold, linear detail of low contrast, tumor masses, contrast ratio and background optical density. The results obtained by this method were compared with the results presented in the visual evaluations performed by the Health Surveillance of Minas Gerais. Through this comparison was possible to demonstrate that the automated methodology is presented as a promising alternative for the reduction or elimination of existing subjectivity in the visual assessment methodology currently in use. (author)

Variations in screening outcome among pairs of screening radiologists at non-blinded double reading of screening mammograms: a population-based study

NARCIS (Netherlands)

Klompenhouwer, E. G.; Duijm, L. E. M.; Voogd, A. C.; den Heeten, G. J.; Nederend, J.; Jansen, F. H.; Broeders, M. J. M.

2014-01-01

Substantial inter-observer variability in screening mammography interpretation has been reported at single reading. However, screening results of pairs of screening radiologists have not yet been published. We determined variations in screening performances among pairs of screening radiologists at

X-ray imaging using amorphous selenium: a photoinduced discharge readout method for digital mammography.

Science.gov (United States)

Rowlands, J A; Hunter, D M; Araj, N

1991-01-01

A new digital image readout method for electrostatic charge images on photoconductive plates is described. The method can be used to read out images on selenium plates similar to those used in xeromammography. The readout method, called the air-gap photoinduced discharge method (PID), discharges the latent image pixel by pixel and measures the charge. The PID readout method, like electrometer methods, is linear. However, the PID method permits much better resolution than scanning electrometers while maintaining quantum limited performance at high radiation exposure levels. Thus the air-gap PID method appears to be uniquely superior for high-resolution digital imaging tasks such as mammography.

Glandular dose and image quality control in mammography facilities with computerized radiography systems

International Nuclear Information System (INIS)

Dantas, Marcelino Vicente de Almeida

2010-01-01

Breast cancer is the most common cancer among women, and early detection is critical to its diagnosis and treatment. To date, the most effective method for early detection of breast cancer has been x-ray mammography for which the screen/film (SF) technique has been the gold standard. However, even though SF combinations have been improved and optimized over the years for breast imaging, there are some critical limitations, including a narrow exposure range, image artifacts, film processing problems, and inflexibility in image processing and film management. In recent years, digital mammography has been introduced in cancer screening programmes with the screen/film techniques gradually being phased out. Computed radiography (CR), also commonly known as photostimulable phosphor (PSP) imaging or storage phosphor, employs reusable imaging plates and associated hardware and software to acquire and to display digital projection radiographs. In this work, a protocol model was tested for performing image quality control and average glandular dose (AGD) evaluation in 19 institutions with computed radiography systems for mammography. The protocol was validated through tests at the Laboratorio de Radioprotecao Aplicada a Mamografia (LARAM) from the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN). The image quality visual evaluation of CDMAM phantom showed that 53% of the facilities were able to produce images of excellent quality. Furthermore, the automated evaluation of image quality, using the analyze software cdcom.exe, showed that 57% of the images were considered to be of good quality. The detector linearity test showed that the CR response is very linear, where 95% of facilities evaluated were considered to be compliant. For the image noise was found that only 20% of facilities are in agreement with the parameters established for this test. The average glandular doses, which patients may be getting to perform an examination, were below the action levels

Decision making and counseling around mammography screening for women aged 80 or older.

Science.gov (United States)

Schonberg, Mara A; Ramanan, Radhika A; McCarthy, Ellen P; Marcantonio, Edward R

2006-09-01

Despite uncertain benefit, many women over age 80 (oldest-old) receive screening mammography. To explore decision-making and physician counseling of oldest-old women around mammography screening. Qualitative research using in-depth semi-structured interviews. Twenty-three women aged 80 or older who received care at a large academic primary care practice (13 had undergone mammography screening in the past 2 years) and 16 physicians at the same center. We asked patients and physicians to describe factors influencing mammography screening decisions of oldest-old women. We asked physicians to describe their counseling about screening to the oldest-old. Patients and/or physicians identified the importance of physician influence, patient preferences, system factors, and social influences on screening decisions. Although physicians felt that patient's health affected screening decisions, few patients felt that health mattered. Three types of elderly patients were identified: (1) women enthusiastic about screening mammography; (2) women opposed to screening mammography; and (3) women without a preference who followed their physician's recommendation. However, physician counseling about mammography screening to elderly women varies; some individualize discussions; others encourage screening; few discourage screening. Physicians report that discussions about stopping screening can be uncomfortable and time consuming. Physicians suggest that more data could facilitate these discussions. Some oldest-old women have strong opinions about screening mammography while others are influenced by physicians. Discussions about stopping screening are challenging for physicians. More data about the benefits and risks of mammography screening for women aged 80 or older could inform patients and improve provider counseling to lead to more rational use of mammography.

Does Performance in Digital Reading Relate to Computer Game Playing? A Study of Factor Structure and Gender Patterns in 15-Year-Olds' Reading Literacy Performance

Science.gov (United States)

Rasmusson, Maria; Åberg-Bengtsson, Lisbeth

2015-01-01

Data from a Swedish PISA-sample were used (1) to identify a digital reading factor, (2) to investigate gender differences in this factor (if found), and (3) to explore how computer game playing might relate to digital reading performance and gender. The analyses were conducted with structural equation modeling techniques. In addition to an overall…

Can positron emission mammography help to identify clinically significant breast cancer in women with suspicious calcifications on mammography?

Energy Technology Data Exchange (ETDEWEB)

Bitencourt, Almir G.V.; Lima, Eduardo N.P.; Macedo, Bruna R.C.; Conrado, Jorge L.F.A.; Marques, Elvira F.; Chojniak, Rubens [A C Camargo Cancer Center-Department of Imaging, Sao Paulo, SP (Brazil)

2017-05-15

To evaluate the diagnostic accuracy of positron emission mammography (PEM) for identifying malignant lesions in patients with suspicious microcalcifications detected on mammography. A prospective, single-centre study that evaluated 40 patients with suspicious calcifications at mammography and indication for percutaneous or surgical biopsy, with mean age of 56.4 years (range: 28-81 years). Patients who agreed to participate in the study underwent PEM with 18F-fluorodeoxyglucose before the final histological evaluation. PEM findings were compared with mammography and histological findings. Most calcifications (n = 34; 85.0 %) were classified as BIRADS 4. On histology, there were 25 (62.5 %) benign and 15 (37.5 %) malignant lesions, including 11 (27.5 %) ductal carcinoma in situ (DCIS) and 4 (10 %) invasive carcinomas. On subjective analysis, PEM was positive in 15 cases (37.5 %) and most of these cases (n = 14; 93.3 %) were confirmed as malignant on histology. There was one false-positive result, which corresponded to a fibroadenoma, and one false negative, which corresponded to an intermediate-grade DCIS. PEM had a sensitivity of 93.3 %, specificity of 96.0 % and accuracy of 95 %. PEM was able to identify all invasive carcinomas and high-grade DCIS (nuclear grade 3) in the presented sample, suggesting that this method may be useful for further evaluation of patients with suspected microcalcifications. (orig.)

THE VALUE OF ULTRASOUND MAMMOGRAPHY IN PALPABLE BREAST MASSES

NARCIS (Netherlands)

VANOORD, JC; VANDERVLIET, AM; THYN, CJP; MAK, B; HOOGEBOOM, GJ

Between January 1987 and May 1988 a prospective study was carried out on 232 women with a palpable breast mass. They underwent physical examination, x-ray mammography and ultrasound mammography. The results of each study were interpreted independently by separate observers, and consensus was

At what age should screening mammography be recommended for Asian women?

Science.gov (United States)

Tsuchida, Junko; Nagahashi, Masayuki; Rashid, Omar M; Takabe, Kazuaki; Wakai, Toshifumi

2015-07-01

Although regular screening mammography has been suggested to be associated with improvements in the relative survival of breast cancer in recent years, the appropriate age to start screening mammography remains controversial. In November 2009, the United States Preventive Service Task Force published updated guidelines for breast cancer, which no longer support routine screening mammography for women aged 40-49 years, but instead, defer the choice of screening in that age group to the patient and physician. The age to begin screening differs between guidelines, including those from the Task Force, the American Cancer Society and the World Health Organization. It remains unclear how this discrepancy impacts patient survival, especially among certain subpopulations. Although the biological characteristics of breast cancer and peak age of incidence differ among different ethnic populations, there have been few reports that evaluate the starting age for screening mammography based on ethnicity. Here, we discuss the benefits and harm of screening mammography in the fifth decade, and re-evaluate the starting age for screening mammography taking ethnicity into account, focusing on the Asian population. Breast cancer incidence peaked in the fifth decade in Asian women, which has been thought to be due to a combination of biological and environmental factors. Previous reports suggest that Asian women in their 40s may receive more benefit and less harm from screening mammography than the age-matched non-Asian US population. Therefore, starting screening mammography at age 40 may be beneficial for women of Asian ethnicity in well-resourced countries, such as Japanese women who reside in Japan. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Time for a re-evaluation of mammography in the young? Results of an audit of mammography in women younger than 40 in a resource restricted environment.

Science.gov (United States)

Taylor, Liezel; Basro, Sarinah; Apffelstaedt, Justus P; Baatjes, Karin

2011-08-01

Mammography in younger women is considered to be of limited value. In a resource restricted environment without access to magnetic resonance imaging (MRI) and with a high incidence of breast cancer in the young, mammography remains an important diagnostic tool. Recent technical advances and better regulation of mammography make a reassessment of its value in these conditions necessary. Data of all the mammograms performed at a tertiary hospital and private breast clinic between January 2003 and July 2009 in women less than 40 years of age were collected. Indications were the presence of a mass, follow-up after primary cancer therapy, and screening for patients perceived at high risk due to a family history or the presence of atypical hyperplasia. Data acquired were as follows: Demographics, prior breast surgery, indication for mammography, outcome of mammography, diagnostic procedures, and their results. Of 2,167 mammograms, 393 were performed for a palpable mass, diagnostic mammography. In these, the overall cancer detection rate was 40%. If the mammography was reported as breast imaging reporting and data system (BIRADS(®)) 5 versus BIRADS(®) 3 and 4 versus BIRADS(®) 1 and 2, a final diagnosis of malignancy was established in 96, 48, and 5%, respectively. Of 367 mammograms done for the follow-up after primary treatment of breast cancer, seven cancers were diagnosed for a detection rate of 1.9%. Of 1,312 mammograms performed for screening, the recall rate was 4%; the biopsy rate 2%, and the cancer diagnosis rate 3/1,000 examinations. In contrast to past series, this series has shown that recent advances in mammography have made it a useful tool in the management of breast problems in young women, notably in a resource-restricted environment. Women for screening should be selected carefully.

Situational quality evaluation of mammography services at state of Minas Gerais, Brazil

International Nuclear Information System (INIS)

Joana, Georgia S.; Oliveira, Mauricio de; Andrade, Mauricio C. de; Cesar, Adriana C.Z.; Peixoto, Joao E.

2011-01-01

Breast cancer is the leading cause of cancer deaths in women. Currently, the most effective method for early detection of this cancer is the mammography, and to achieve the standard definition and contrast, the whole system of imaging must operate under optimal conditions. This paper presents the results of the assessment of mammography centers in the state of Minas Gerais, which was held with the aim of supporting the actions of the State Program of Quality Control in Mammography. These results indicated that less than half of mammography achieved the minimum standard of image quality, endorsing the need of a monitoring more efficient and effective, which led to the establishment, in Minas Gerais, of the monthly monitoring of image quality in mammography. (author)

Computer-Based Reading and Spelling Practice for Children with Learning Disabilities.

Science.gov (United States)

van Daal, Victor H. P.; van der Leij, Aryan

1992-01-01

This study with 28 Netherlands children (mean age 9 years, 7 months) with written language disorders found that copying words from the computer screen resulted in significantly fewer spelling errors on the posttest than writing words from memory and that both these forms of practice led to fewer spelling errors than only reading the words.…

Factors influencing elderly women's mammography screening decisions: implications for counseling.

Science.gov (United States)

Schonberg, Mara A; McCarthy, Ellen P; York, Meghan; Davis, Roger B; Marcantonio, Edward R

2007-11-16

Although guidelines recommend that clinicians consider life expectancy before screening older women for breast cancer, many older women with limited life expectancies are screened. We aimed to identify factors important to mammography screening decisions among women aged 80 and older compared to women aged 65-79. Telephone surveys of 107 women aged 80+ and 93 women aged 65-79 randomly selected from one academic primary care practice who were able to communicate in English (60% response rate). The survey addressed the following factors in regards to older women's mammography screening decisions: perceived importance of a history of breast disease, family history of breast cancer, doctor's recommendations, habit, reassurance, previous experience, mailed reminder cards, family/friend's recommendations or experience with breast cancer, age, health, and media. The survey also assessed older women's preferred role in decision making around mammography screening. Of the 200 women, 65.5% were non-Hispanic white and 82.8% were in good to excellent health. Most (81.3%) had undergone mammography in the past 2 years. Regardless of age, older women ranked doctor's recommendations as the most important factor influencing their decision to get screened. Habit and reassurance were the next two highly ranked factors influencing older women to get screened. Among women who did not get screened, women aged 80 and older ranked age and doctor's counseling as the most influential factors and women aged 65-79 ranked a previous negative experience with mammography as the most important factor. There were no significant differences in preferred role in decision-making around mammography screening by age, however, most women in both age groups preferred to make the final decision on their own (46.6% of women aged 80+ and 50.5% of women aged 65-79). While a doctor's recommendation is the most important factor influencing elderly women's mammography screening decisions, habit and reassurance

Patterns and determinants of mammography screening in Lebanese women

Directory of Open Access Journals (Sweden)

Nadia Elias

2017-03-01

Providing mammography free-of-charge may alleviate some obstacles among women with socio-economic disadvantage. Stressing that good results one year do not make the cancer less likely or repeating the test less important, as well as improving the comfort of mammography testing could ensure test repeating.

The relationship of social support concept and repeat mammography among Iranian women.

Science.gov (United States)

Farhadifar, Fariba; Taymoori, Parvaneh; Bahrami, Mitra; Zarea, Shamsy

2015-10-24

Breast cancer ranks as the first most common cancer among the Iranian women. The regular repeat of mammography with 1-2 year intervals leads to the increased efficiency of early detection of breast cancer. The present study examined the predictors of repeat mammography. It was hypothesized that higher social support is connected with mammography repeat. A cross-sectional study was carried out among 400 women 50 years and older in Sanandaj, Iran. Data was collected by the questionnaire including information on socio demographical variables and measuring social support level. Data was analyzed by SPSS16 software. Multiple logistic regression was used to determine the predictive power of demographic variables and dimensions of social support for repeat mammography. Women aged 50-55 years had three times odds of repeat mammography compared to women aged 56-60 years) OR, 3.02). Married women had greater odds of repeat mammography compared to single women (P women with higher social support was 0.93 times greater than the women with lower social support (OR, 0.93; 95 % CI, 0.91-0.95; P women are less likely repeat mammography than other Asian women. Identifying the associations between perceived social support and repeat mammography may offer detailed information to allow for future study and guide the development of interventions not only for Iranian women but also for similar cultural that received pay too little attention to date in the breast cancer literature.

Rayleigh imaging in spectral mammography

Science.gov (United States)

Berggren, Karl; Danielsson, Mats; Fredenberg, Erik

2016-03-01

Spectral imaging is the acquisition of multiple images of an object at different energy spectra. In mammography, dual-energy imaging (spectral imaging with two energy levels) has been investigated for several applications, in particular material decomposition, which allows for quantitative analysis of breast composition and quantitative contrast-enhanced imaging. Material decomposition with dual-energy imaging is based on the assumption that there are two dominant photon interaction effects that determine linear attenuation: the photoelectric effect and Compton scattering. This assumption limits the number of basis materials, i.e. the number of materials that are possible to differentiate between, to two. However, Rayleigh scattering may account for more than 10% of the linear attenuation in the mammography energy range. In this work, we show that a modified version of a scanning multi-slit spectral photon-counting mammography system is able to acquire three images at different spectra and can be used for triple-energy imaging. We further show that triple-energy imaging in combination with the efficient scatter rejection of the system enables measurement of Rayleigh scattering, which adds an additional energy dependency to the linear attenuation and enables material decomposition with three basis materials. Three available basis materials have the potential to improve virtually all applications of spectral imaging.

Potential Cost Savings of Contrast-Enhanced Digital Mammography.

Science.gov (United States)

Patel, Bhavika K; Gray, Richard J; Pockaj, Barbara A

2017-06-01

The purpose of this article is to discuss whether the sensitivity and specificity of contrast-enhanced digital mammography (CEDM) render it a viable diagnostic alternative to breast MRI. That CEDM couples low-energy images (comparable to the diagnostic quality of standard mammography) and subtracted contrast-enhanced mammograms make it a cost-effective modality and a realistic substitute for the more costly breast MRI.

Mammography in Norway: Image quality and total performance

International Nuclear Information System (INIS)

Olsen, J.B.; Skretting, A.; Widmark, A.

1997-04-01

This report describes a method for assessing the total performance in mammography based on Receiver Operating Characteristic (ROC) analysis. In the time period from December 1993 to March 1994 the method was applied to assess the total performance of all the 45 Norwegian mammography laboratories operative at that time. Image quality characteristics in each laboratory was established by use of well-known phantoms

Object characterization simulator for estimating compressed breast during mammography

International Nuclear Information System (INIS)

Pinheiro, Luciana de J.S.; Rio, Margarita Chevalier del

2011-01-01

The measurement of the thickness of a compressed breast during the mammography test is necessary in order to calculate the glandular dose in mammography procedures, in an analysis of risk/benefit, given that the target organ in these procedures is highly sensitive to ionising radiation. However, mammography is a test of utmost importance in diagnosis. In theory, it may be possible to calculate the thickness of the compressed breast through the measurements of the focus object distance by using projections of radio opaque objects fixed to the compression tray. The facilities of the Laboratory of Applied Radioprotection to Mammography - LARAM were used for this study, as well as breast simulators with well defined thickness, in the assembly of the techniques for the measurement of the thickness of the compressed breast. The results showed that it is possible to determine this thickness through calculations and simulators through this method which is susceptible to be adequate to the dosimetry. (author)

Estimation of patient dose in mammography screening examinations

International Nuclear Information System (INIS)

Suzuki, S.; Fujii, S.; Orito, T.; Asada, Y.; Koga, S.; Horita, K.; Kido, C.

1996-01-01

Mammography is one of the most effective examinations for detecting breast carcinoma. Although the dose is usually much higher than that in other types of X-ray examination, that is accepted by the patient because for fears of suffering cancer. Benefit of relatively high doses derived from mammographic examinations is considered to well exceed the risk of cancer induction by radiation exposure. The purpose of this study is to investigate patient dose of mammography in Japan by questionnaire sent to 531 institutions selected from whole Japan and direct measurements carried out in 28 hospitals in Aichi Prefecture. The user's guide in mammography published by NCRP and Quality Assurance Program of American College of Radiology were used to assess the exposure and image quality of mammogram. (author)

Contrast-enhanced spectral mammography in patients referred from the breast cancer screening programme.

Science.gov (United States)

Lobbes, Marc B I; Lalji, Ulrich; Houwers, Janneke; Nijssen, Estelle C; Nelemans, Patty J; van Roozendaal, Lori; Smidt, Marjolein L; Heuts, Esther; Wildberger, Joachim E

2014-07-01

Feasibility studies have shown that contrast-enhanced spectral mammography (CESM) increases diagnostic accuracy of mammography. We studied diagnostic accuracy of CESM in patients referred from the breast cancer screening programme, who have a lower disease prevalence than previously published papers on CESM. During 6 months, all women referred to our hospital were eligible for CESM. Two radiologists blinded to the final diagnosis provided BI-RADS classifications for conventional mammography and CESM. Statistical significance of differences between mammography and CESM was calculated using McNemar's test. Receiver operating characteristic (ROC) curves were constructed for both imaging modalities. Of the 116 eligible women, 113 underwent CESM. CESM increased sensitivity to 100.0% (+3.1%), specificity to 87.7% (+45.7%), PPV to 76.2% (+36.5%) and NPV to 100.0% (+2.9%) as compared to mammography. Differences between conventional mammography and CESM were statistically significant (p mammography, AUC was 0.779. With CESM, AUC increased to 0.976 (p mammography, even in lower prevalence patient populations such as referrals from breast cancer screening. • CESM is feasible in the workflow of referrals from routine breast screening. • CESM is superior to mammography, even in low disease prevalence populations. • CESM has an extremely high negative predictive value for breast cancer. • CESM is comparable to MRI in assessment of breast cancer extent. • CESM is comparable to histopathology in assessment of breast cancer extent.

Bi-directional x-ray phase-contrast mammography.

Directory of Open Access Journals (Sweden)

Kai Scherer

Full Text Available Phase-contrast x-ray imaging is a promising improvement of conventional absorption-based mammography for early tumor detection. This potential has been demonstrated recently, utilizing structured gratings to obtain differential phase and dark-field scattering images. However, the inherently anisotropic imaging sensitivity of the proposed mono-directional approach yields only insufficient diagnostic information, and has low diagnostic sensitivity to highly oriented structures. To overcome these limitations, we present a two-directional x-ray phase-contrast mammography approach and demonstrate its advantages by applying it to a freshly dissected, cancerous mastectomy breast specimen. We illustrate that the two-directional scanning procedure overcomes the insufficient diagnostic value of a single scan, and reliably detects tumor structures, independently from their orientation within the breast. Our results indicate the indispensable diagnostic necessity and benefit of a multi-directional approach for x-ray phase-contrast mammography.

Contrast-enhanced spectral mammography in patients referred from the breast cancer screening programme

Energy Technology Data Exchange (ETDEWEB)

Lobbes, Marc B.I.; Wildberger, Joachim E. [Maastricht University Medical Center, Department of Radiology, Maastricht (Netherlands); GROW School for Oncology and Developmental Biology, Maastricht (Netherlands); Lalji, Ulrich; Houwers, Janneke; Nijssen, Estelle C. [Maastricht University Medical Center, Department of Radiology, Maastricht (Netherlands); Nelemans, Patty J. [Maastricht University, Department of Epidemiology, Maastricht (Netherlands); Roozendaal, Lori van; Heuts, Esther [Maastricht University Medical Center, Department of Surgical Oncology, Maastricht (Netherlands); Smidt, Marjolein L. [Maastricht University Medical Center, Department of Surgical Oncology, Maastricht (Netherlands); GROW School for Oncology and Developmental Biology, Maastricht (Netherlands)

2014-07-15

Feasibility studies have shown that contrast-enhanced spectral mammography (CESM) increases diagnostic accuracy of mammography. We studied diagnostic accuracy of CESM in patients referred from the breast cancer screening programme, who have a lower disease prevalence than previously published papers on CESM. During 6 months, all women referred to our hospital were eligible for CESM. Two radiologists blinded to the final diagnosis provided BI-RADS classifications for conventional mammography and CESM. Statistical significance of differences between mammography and CESM was calculated using McNemar's test. Receiver operating characteristic (ROC) curves were constructed for both imaging modalities. Of the 116 eligible women, 113 underwent CESM. CESM increased sensitivity to 100.0 % (+3.1 %), specificity to 87.7 % (+45.7 %), PPV to 76.2 % (+36.5 %) and NPV to 100.0 % (+2.9 %) as compared to mammography. Differences between conventional mammography and CESM were statistically significant (p < 0.0001). A similar trend was observed in the ROC curve. For conventional mammography, AUC was 0.779. With CESM, AUC increased to 0.976 (p < 0.0001). In addition, good agreement between tumour diameters measured using CESM, breast MRI and histopathology was observed. CESM increases diagnostic performance of conventional mammography, even in lower prevalence patient populations such as referrals from breast cancer screening. (orig.)

Compliance with European Guidelines for Diagnostic Mammography in a Decentralized Health-Care Setting

International Nuclear Information System (INIS)

Jensen, A.; Mikkelsen, G.J.; Vestergaard, M.; Lynge, E.; Vejborg, I.

2005-01-01

Purpose: To evaluate the compliance of Danish mammography clinics with requirements concerning organization, activity volume, and assessment procedures from two European guidelines for quality assurance in diagnostic mammography (EUSOMA and EUREF). Material and Methods: We used individual records on all diagnostic mammographies performed in Denmark in 2000, and questionnaires given to Danish mammography clinics in 2000, 2002, and 2004. Results: The study showed a marked centralization of the diagnostic activity from 2000 to 2004 to a smaller number of public breast assessment centers with full multidisciplinary breast assessment. However, a relatively large number of these centers did not comply with the activity volume requirement of 2000 mammograms per clinic per year. The number of private diagnostic mammography clinics performing basic diagnostic mammography has remained fairly stable in the period 2000 to 2004. Compared with public breast assessment centers, the private diagnostic mammography clinics had a lower compliance with activity volume requirements. Conclusion: A marked proportion of Danish public breast assessment centers operate with less than optimal activity volume, suggesting that further centralization would be appropriate. The situation in private diagnostic mammography clinics may cause concern, as our study showed that the majority of these clinics did not meet the activity volume requirements

Contrast-enhanced spectral mammography in patients referred from the breast cancer screening programme

International Nuclear Information System (INIS)

Lobbes, Marc B.I.; Wildberger, Joachim E.; Lalji, Ulrich; Houwers, Janneke; Nijssen, Estelle C.; Nelemans, Patty J.; Roozendaal, Lori van; Heuts, Esther; Smidt, Marjolein L.

2014-01-01

Feasibility studies have shown that contrast-enhanced spectral mammography (CESM) increases diagnostic accuracy of mammography. We studied diagnostic accuracy of CESM in patients referred from the breast cancer screening programme, who have a lower disease prevalence than previously published papers on CESM. During 6 months, all women referred to our hospital were eligible for CESM. Two radiologists blinded to the final diagnosis provided BI-RADS classifications for conventional mammography and CESM. Statistical significance of differences between mammography and CESM was calculated using McNemar's test. Receiver operating characteristic (ROC) curves were constructed for both imaging modalities. Of the 116 eligible women, 113 underwent CESM. CESM increased sensitivity to 100.0 % (+3.1 %), specificity to 87.7 % (+45.7 %), PPV to 76.2 % (+36.5 %) and NPV to 100.0 % (+2.9 %) as compared to mammography. Differences between conventional mammography and CESM were statistically significant (p < 0.0001). A similar trend was observed in the ROC curve. For conventional mammography, AUC was 0.779. With CESM, AUC increased to 0.976 (p < 0.0001). In addition, good agreement between tumour diameters measured using CESM, breast MRI and histopathology was observed. CESM increases diagnostic performance of conventional mammography, even in lower prevalence patient populations such as referrals from breast cancer screening. (orig.)

Analysis of medical exposures in digital mammography

International Nuclear Information System (INIS)

Oliveira, Sergio R.; Mantuano, Natalia O.; Albrecht, Afonso S.

2014-01-01

Currently, the use of digital mammography in the early diagnosis of breast cancer is increasingly common due to the production of high definition image that allows to detect subtle changes in breast images profiles. However it is necessary to be an improvement of the technique used since some devices offer minimization parameters of entrance dose to the skin. Thus, this study seeks to examine how the qualification of technical professionals in radiology interferes with the use of the techniques applied in mammography. For this, survey was carried out in a hospital in the city of Rio de Janeiro, which evaluated the scans of 1190 patients undergoing routine mammography (It is considered routinely the 4 basic exhibitions: with 2 flow skull and 2 medium oblique side, excluding repeats and supplements) in 2013. The medical exposures analyzed obtained from a single full digital equipment, model Senographe DS were compared with three different procedures performed by professionals in mammography techniques. The images were classified according to exposure techniques available in the equipment: Standard (STD), contrast (CNT) and dose (dose), and to be selected as breast density of the patient. Comparing the variation of the radiographic technique in relation to the professional who made the exhibition, what is observed is that the professional B presented the best conduct in relation to radiological protection, because she considered breast density in the choice of technical equipment parameter. The professional A, which is newly formed, and C, which has more service time, almost did not perform variations in the pattern of exposure, even for different breast densities. Thus, we can conclude that there is a need to update the professionals so that the tools available of dose limitation and mamas variability to digital mammography are efficiently employed in the service routine and thus meet the requirements of current legislation

Patterns and determinants of mammography screening in Lebanese women.

Science.gov (United States)

Elias, Nadia; Bou-Orm, Ibrahim R; Adib, Salim M

2017-03-01

The associations of ever using and/or repeating a mammography test with psychosocial and socio-demographic factors were surveyed in 2014 among Lebanese women ≥ 40. A sample of 2400 women was selected across Lebanon. Variables with significant bivariate associations with various types of behaviors were entered in multivariate analysis. Of the total, 105 women (4·4%) had never heard of mammography as a tool for early breast cancer detection. Among the remaining 2295, 45% had ever used it, of whom 10% had obtained it for the first time within the 12 months preceding the survey. Repeaters were 67% of 926 women who had the time opportunity to do so (median lifetime frequency: 2). Older age, higher socio-economic status (SES) and living within the Greater Beirut (GB) area were significantly associated with ever-use. Within GB, psychosocial factors such as perceived susceptibility and benefits were most strongly associated with ever-use. Outside GB, socio-economic advantage seemed to mostly affect ever-use. Only 4% reported opposition from husbands to their mammography, and husband's support was significant for adherence to mammography guidelines mostly outside GB. Higher education emerged also as a significant socio-demographic determinant for ever-repeating in all regions. Perceived comfort of the previous test strongly affected the likelihood of repeating it. Providing mammography free-of-charge may alleviate some obstacles among women with socio-economic disadvantage. Stressing that good results one year do not make the cancer less likely or repeating the test less important, as well as improving the comfort of mammography testing could ensure test repeating.

The interplay of attention economics and computer-aided detection marks in screening mammography

Science.gov (United States)

Schwartz, Tayler M.; Sridharan, Radhika; Wei, Wei; Lukyanchenko, Olga; Geiser, William; Whitman, Gary J.; Haygood, Tamara Miner

2016-03-01

Introduction: According to attention economists, overabundant information leads to decreased attention for individual pieces of information. Computer-aided detection (CAD) alerts radiologists to findings potentially associated with breast cancer but is notorious for creating an abundance of false-positive marks. We suspected that increased CAD marks do not lengthen mammogram interpretation time, as radiologists will selectively disregard these marks when present in larger numbers. We explore the relevance of attention economics in mammography by examining how the number of CAD marks affects interpretation time. Methods: We performed a retrospective review of bilateral digital screening mammograms obtained between January 1, 2011 and February 28, 2014, using only weekend interpretations to decrease distractions and the likelihood of trainee participation. We stratified data according to reader and used ANOVA to assess the relationship between number of CAD marks and interpretation time. Results: Ten radiologists, with median experience after residency of 12.5 years (range 6 to 24,) interpreted 1849 mammograms. When accounting for number of images, Breast Imaging Reporting and Data System category, and breast density, increasing numbers of CAD marks was correlated with longer interpretation time only for the three radiologists with the fewest years of experience (median 7 years.) Conclusion: For the 7 most experienced readers, increasing CAD marks did not lengthen interpretation time. We surmise that as CAD marks increase, the attention given to individual marks decreases. Experienced radiologists may rapidly dismiss larger numbers of CAD marks as false-positive, having learned that devoting extra attention to such marks does not improve clinical detection.

Patients Mammographic Dose Survey in a Sample of Slovak Mammography Departments

International Nuclear Information System (INIS)

Nikodemova, D.; Horvathova, M.; Gbelcova, L.

2008-01-01

Breast cancer is the most frequent cancer and the most frequent cause of cancer induced deaths in Europe. Demographic trends indicate a continuing increase in this substantial public health problem. Systematic early detection, effective diagnostic pathways and high quality services have the ability for lowering the breast cancer mortality rates and for reducing the burden of this disease in the population The widespread use of mammography for early breast cancer detection is highly accepted all over the world. For achievement of a successful national mammography programme in Slovakia, a national QA/QC mammography system was introduced. Coming from alarming values of increase of malignant neoplasm of breast in Slovakia a national mammography audit has been initiated, performed in three runs and working in three phases: assessment of existing status of practice and equipment performance, as well as education and training of radiologists and radiographers of 42 mammography departments; implementation of technical quality programme and patient dose evaluation; clinical image evaluation. Preventive mammography in spite of being a reasonable examination, which represents health benefit for patient, exceed also the health risk. In 1991-1996 mammographic examination created 1.3% from all medical radiodiagnostic expositions made in Slovakia. In 2005 there were realized 241 208 mammographic examinations, 140 798 of them were noticed like preventive examinations. In 2006 the number of all mammographic examinations in Slovakia increased to 271 755 and of them 156 199 were preventive mammographic examinations. In our presentation we tried to establish the average absorbed glandular doses of patients undergoing mammography examinations in 10 selected departments and to compare the obtained results with European diagnostic reference values. The obtained values were used for the proposal of a new national diagnostic reference value for mammography examinations

Digital mammography screening: average glandular dose and first performance parameters

International Nuclear Information System (INIS)

Weigel, S.; Girnus, R.; Czwoydzinski, J.; Heindel, W.; Decker, T.; Spital, S.

2007-01-01

Purpose: The Radiation Protection Commission demanded structured implementation of digital mammography screening in Germany. The main requirements were the installation of digital reference centers and separate evaluation of the fully digitized screening units. Digital mammography screening must meet the quality standards of the European guidelines and must be compared to analog screening results. We analyzed early surrogate indicators of effective screening and dosage levels for the first German digital screening unit in a routine setting after the first half of the initial screening round. Materials and Methods: We used three digital mammography screening units (one full-field digital scanner [DR] and two computed radiography systems [CR]). Each system has been proven to fulfill the requirements of the National and European guidelines. The radiation exposure levels, the medical workflow and the histological results were documented in a central electronic screening record. Results: In the first year 11,413 women were screened (participation rate 57.5 %). The parenchymal dosages for the three mammographic X-ray systems, averaged for the different breast sizes, were 0.7 (DR), 1.3 (CR), 1.5 (CR) mGy. 7 % of the screened women needed to undergo further examinations. The total number of screen-detected cancers was 129 (detection rate 1.1 %). 21 % of the carcinomas were classified as ductal carcinomas in situ, 40 % of the invasive carcinomas had a histological size ≤ 10 mm and 61 % < 15 mm. The frequency distribution of pT-categories of screen-detected cancer was as follows: pTis 20.9 %, pT1 61.2 %, pT2 14.7 %, pT3 2.3 %, pT4 0.8 %. 73 % of the invasive carcinomas were node-negative. (orig.)

Comparison of TLD air kerma measurements in mammography

International Nuclear Information System (INIS)

Pernicka, F.

2002-01-01

The mammography examination is usually targeted at asymptomatic women so the narrow balance between benefit and undesirable effects is important. During the past few decades there have been significant advances in the equipment used for mammography. Even when the latest equipment and imaging systems are used, there is considerable variation from centre-to-centre in the choice of imaging parameters and techniques. There may be quite large differences in image quality and breast dose among the centres. A Co-ordinated Research Programme on 'Image quality and patient dose optimization in mammography in Eastern European Countries' was conducted by the IAEA, aiming at defining a methodology for the implementation of a quality assurance (QA) programme in mammography and at exercising the assessment of image quality and patient doses in a sample of hospitals in East European countries. Selected mammography clinics from Czech Republic, Hungary, Poland, Romania and Slovakia participate in the project. The teams consisted of experienced clinicians and physicists. They were supported by a group of experts (clinicians and medical physicists) from France, Italy and Spain. As an outcome of the project, improvements in these indicators (image quality and patient dose) after the implementation of the QA programme are expected. A comparison of dosimetry systems has been organized to assure that dosimetry measurements done in the frame of the project are comparable and traceable to the international measurement system. All five East European countries plus Spain took part in the exercise. The thermoluminescent (TL) method was selected for the comparison

[Commentary on the planned restructuring of mammography screening in Austria].

Science.gov (United States)

Vutuc, Christian; Haidinger, Gerald

2011-08-01

With regards to the planned reorganisation of screening mammography in Austria - from an opportunistic to an organised system - the problems related with such a change are depicted from an epidemiological point of view. We were able to demonstrate earlier that opportunistic screening mammography matches the results of controlled screening mammography in Finland and Sweden. Switching to a controlled system in Austria would - besides the need for a change in legislation - lead to enormous expenditures in terms of resources needed and moreover, it could be not evaluated for years.

Anxiety in mammography: mammographers' and clients' perspectives

International Nuclear Information System (INIS)

Galletta, S.; Joel, N.; Maguire, R.; Weaver, K.; Poulos, A.

2003-01-01

The aim of this study was to identify causes of anxiety experienced by mammographers and clients during mammography and strategies to decrease the anxiety generated by the mammographic procedure. Two questionnaires were distributed: one to mammographers in public and private centres within NSW, the other to women (clients) who have experienced mammography. Mammographers' and clients' rankings of causes of clients' anxiety demonstrated many similarities indicating the mammographers' acknowledgement of factors contributing to client anxiety. Thematic analysis provided important qualitative data concerning anxiety experienced by both mammographers and clients and the influence of mammographer and client behaviour on that anxiety. The results of this study have provided important new knowledge for mammographic practice and mammography education. By understanding the causes of anxiety experienced by clients, mammographers can provide an informed, empathetic approach to the mammographic process. By acknowledging factors which increase their own anxiety mammographers can reduce the impact of this on themselves and on their clients. Copyright (2003) Australian Institute of Radiography

Breast cancer screening: the underuse of mammography

International Nuclear Information System (INIS)

Fox, S.; Baum, J.K.; Klos, D.S.; Tsou, C.V.

1985-01-01

The early detection of breast cancer is promoted by the American Cancer Society (ACS) and the American College of Radiology (ACR) by encouraging the regular use of three types of screening: breast self-examination (BSE), the clinical breast examination, and mammography. In August 1983, the ACS publicized seven recommendations pertaining to screening, including a revised statement about the routine use of mammography for women between the ages of 40 and 49 years. In response to the ACS statement, the present study assessed compliance with the updated recommendations for all three types of screening. The results show reasonable rates of compliance for the BSE (53%-69%) and clinical examination (70%-78%). In contrast, only 19% of the women between the ages of 35 and 49 and 25% of the women older than 50 reported complying with the recommendation to undergo one baseline screening mammogram. Some implications for health education by physicians and the professional education of physicians in the use of mammography are discussed

Virtual Machine Scheduling in Dedicated Computing Clusters

CERN Document Server

Boettger, Stefan; Zicari, V Roberto

2014-01-08

Time-critical applications process a continuous stream of input data and have to meet specific timing constraints. A common approach to ensure that such an application satisfies its constraints is over-provisioning: The application is deployed in a dedicated cluster environment with enough processing power to achieve the target performance for every specified data input rate. This approach comes with a drawback: At times of decreased data input rates, the cluster resources are not fully utilized. A typical use case is the HLT-Chain application that processes physics data at runtime of the ALICE experiment at CERN. From a perspective of cost and efficiency it is desirable to exploit temporarily unused cluster resources. Existing approaches aim for that goal by running additional applications. These approaches, however, a) lack in flexibility to dynamically grant the time-critical application the resources it needs, b) are insufficient for isolating the time-critical application from harmful side-effects i...

Local recurrences after conservative surgery and irradiation for breast cancer: Diagnosis with mammography and ultrasound. Mammographie und Sonographie in der Rezidivdiagnostik nach brusterhaltender Therapie des Mammakarzinoms

Energy Technology Data Exchange (ETDEWEB)

Buchberger, W; Hamberger, L; Schoen, G [Innsbruck Univ. (Austria). Universitaetsklinik fuer Radiodiagnostik; Steixner, G; Fritsch, E [Innsbruck Univ. (Austria). Universitaetsklinik fuer Strahlentherapie

1991-06-01

89 patients, who underwent conservative surgery for breast cancer were followed up with mammography and real-time sonography. 78 patients underwent postoperative irradiation. Depending on the time interval between irradiation and examination various alterations in mammographic and sonographic patterns were evident. Of 14 biospy-confirmed local recurrences, 11 were diagnosed by mammography and 12 by sonography. Combined use of mammography and sonography should therefore lead to better results in the diagnosis of local recurrences and to a reduction of unnecessary biopsies. (orig./GDG).

Computer-aided diagnosis for screening of breast cancer on mammograms. Current status and future potential

International Nuclear Information System (INIS)

Doi, Kunio

2007-01-01

Described are the history, current status and future potential of computer-aided diagnosis (CAD) with particular emphasis on screening mammography for breast cancer. The systematic basic and clinical studies on CAD started around 20 years before and the significance of CAD has been well recognized to be evident because of human errors occurring in the visual check by doctors of so numerous screening images. Improvement of diagnostic accuracy by CAD has been demonstrated by statistical analysis of ROC (receiver operating characteristic) curves. In mammography, reviewed is detection of the early stage breast cancer like microcalcifications by computer alone, by CAD plus one or more doctors' reading, and by practical clinical CAD diagnosis. For differential diagnosis for malignancy, microcalcifications and masses are given their characteristic image properties and the results are that the Az-value (area under ROC curve) is higher in CAD than in doctor's (0.80 vs 0.61) in the former and, doctor's (0.93) is improved by CAD to 0.96 in the latter masses. In this diagnosis, similar images in the digital database are useful and the database can learn by repeated input of individual data by neural network. Detection of the lesion and especially, its differential diagnosis will be more important in parallel to database development and CAD will be also useful for doctor' carrier as an educational mean. (R.T.)

Design and Construction of Computer-Assisted Instructional Material: A Handbook for Reading/Language Arts Teachers.

Science.gov (United States)

Balajthy, Ernest

Intended for reading and language arts teachers at all educational levels, this guide presents information to be used by teachers in constructing their own computer assisted educational software using the BASIC programming language and Apple computers. Part 1 provides an overview of the components of traditional tutorial and drill-and-practice…

Image quality and radiation exposure in digital storage plate mammography with magnification technique

International Nuclear Information System (INIS)

Fiedler, E.; Aichinger, U.; Boehner, C.; Schulz-Wendtland, R.; Bautz, W.; Saebel, M.

1999-01-01

Purpose: Comparison of image quality between digital phosphor storage plate mammography in magnification technique and a conventional film screen system regarding the special aspect of radiation exposure. Materials and Methods: Radiograms of a RMI-mammography phantom were acquired using a conventional film screen system and two digital storage plate systems. Additionally, the radiograms of one digital system were postprocessed emphasizing contrast and included in the comparison. Results: The detectability of details in storage plate mammographies with magnification technique is almost equal to that of film screen mammographies. Thereby, lower radiation exposures were necessary using the digital systems. Conclusions: Based on these results, storage plate mammography in magnification technique is used in clinical routine at our institution. The correct parameters in image postprocessing are of elementary importance for detail detectability. Future studies must show, whether the lower radiation exposure in digital radiograms of the breast, revealing much higher background noise, will allow the same detail detectability as film screen mammographies. (orig.) [de

Ultrasound as an Adjunct to Mammography for Breast Cancer Screening: A Health Technology Assessment

Science.gov (United States)

Nikitovic-Jokic, Milica; Tu, Hong Anh; Palimaka, Stefan; Higgins, Caroline; Holubowich, Corinne

2016-01-01

Background Screening with mammography can detect breast cancer early, before clinical symptoms appear. Some cancers, however, are not captured with mammography screening alone. Ultrasound has been suggested as a safe adjunct screening tool that can detect breast cancers missed on mammography. We investigated the benefits, harms, cost-effectiveness, and cost burden of ultrasound as an adjunct to mammography compared with mammography alone for screening women at average risk and at high risk for breast cancer. Methods We searched Ovid MEDLINE, Ovid Embase, EBM Reviews, and the NHS Economic Evaluation Database, from January 1998 to June 2015, for evidence of effectiveness, harms, diagnostic accuracy, and cost-effectiveness. Only studies evaluating the use of ultrasound as an adjunct to mammography in the specified populations were included. We also conducted a cost analysis to estimate the costs in Ontario over the next 5 years to fund ultrasound as an adjunct to mammography in breast cancer screening for high-risk women who are contraindicated for MRI, the current standard of care to supplement mammography. Results No studies in average-risk women met the inclusion criteria of the clinical review. We included 5 prospective, paired cohort studies in high-risk women, 4 of which were relevant to the Ontario context. Adjunct ultrasound identified between 2.3 and 5.9 additional breast cancers per 1,000 screens. The average pooled sensitivity of mammography and ultrasound was 53%, a statistically significant increase relative to mammography alone (absolute increase 13%; P screening alone. The GRADE for this body of evidence was low. Additional annual costs of using breast ultrasound as an adjunct to mammography for high-risk women in Ontario contraindicated for MRI would range from $15,500 to $30,250 in the next 5 years. Conclusions We found no evidence that evaluated the comparative effectiveness or diagnostic accuracy of screening breast ultrasound as an adjunct to

[Mammography screening of breast cancer in Tunisia. Results of first experience].

Science.gov (United States)

Kribi, Lilia; Sellami, Dorra; el Amri, Aïda; Mnif, Nejla; Ellouze, Thouraya; Chebbi, Ali; Ben Romdhane, Khaled; Hamza, Radhi

2003-01-01

This article reports the results of a mammography screening program of breast cancer, realized in the department of Radiology, Charles Nicolle hospital. A free screening mammography with two incidences was offered to women aged from 40 to 70 years old. 2200 mammographies were realized from May 1995 till July 1997. Women having a positive test benefited of a diagnostic explorations in the same unity. The positive test rate was 24%. Predictive positive value was 31%. This program allowed to detect 10 subclinical cancers, corresponding to a rate of detection of 4.5 cancers for 1000 women. This program is a first experience which demonstrated the feasibility of the mammography screening to wide scale and allowed the medical and paramedical team to acquire an experience.

Benefits, risks, and costs of mammography

International Nuclear Information System (INIS)

Richter, B.; Rausch, L.

1977-01-01

The risk seems to be acceptable if the age-dependency of the frequency of breast cancer is disregarded, i.e. if calculation is done with average values, as is being done frequently (15, 25, 32, 48). This procedure however veils the real circumstances in the examination of young women thus also veiling a risk which could otherwise be made precise and avoidable. The risk of radiation-induced cancerogenesis in the female breast was verified by similar statements made by several empiric investigations on man. The course of the dose-effect-relation in the region of few rad is still unexplained however, although the results do not contradict to the assumption of a linear dose-effect-relation. Thus it seems not advisable to ignore the induction of carcinomas by x-radiation for the sphere of mammography with the doses usually applied today. A reduction of radiation exposition by dose-saving measures to one tenth of the present value (or less) however would make the risk highly unimportant. Advantage/risk/cost-analyses should encourage the responsible persons to make reasonable proposals for the application of methods, in this case mammography. The discouraging of patients whom mammography is indicated for would be a side-effect which is not desired. Just as wrong would be the stimulation of an unjustified feeling of being sure and the demand for costly medical measures by uncritical reports of success. The indication of the considerably high costs of mammography should, together with the advantage expected, be a quantitative criterion for the optimal distribution of limited means the necessity of which cannot be denied. (orig.) [de

Factors influencing elderly women's mammography screening decisions: implications for counseling

Directory of Open Access Journals (Sweden)

Davis Roger B

2007-11-01

Full Text Available Abstract Background Although guidelines recommend that clinicians consider life expectancy before screening older women for breast cancer, many older women with limited life expectancies are screened. We aimed to identify factors important to mammography screening decisions among women aged 80 and older compared to women aged 65–79. Methods Telephone surveys of 107 women aged 80+ and 93 women aged 65–79 randomly selected from one academic primary care practice who were able to communicate in English (60% response rate. The survey addressed the following factors in regards to older women's mammography screening decisions: perceived importance of a history of breast disease, family history of breast cancer, doctor's recommendations, habit, reassurance, previous experience, mailed reminder cards, family/friend's recommendations or experience with breast cancer, age, health, and media. The survey also assessed older women's preferred role in decision making around mammography screening. Results Of the 200 women, 65.5% were non-Hispanic white and 82.8% were in good to excellent health. Most (81.3% had undergone mammography in the past 2 years. Regardless of age, older women ranked doctor's recommendations as the most important factor influencing their decision to get screened. Habit and reassurance were the next two highly ranked factors influencing older women to get screened. Among women who did not get screened, women aged 80 and older ranked age and doctor's counseling as the most influential factors and women aged 65–79 ranked a previous negative experience with mammography as the most important factor. There were no significant differences in preferred role in decision-making around mammography screening by age, however, most women in both age groups preferred to make the final decision on their own (46.6% of women aged 80+ and 50.5% of women aged 65–79. Conclusion While a doctor's recommendation is the most important factor influencing

MammoGrid: a mammography database

CERN Multimedia

2002-01-01

What would be the advantages if physicians around the world could gain access to a unique mammography database? The answer may come from MammoGrid, a three-year project under the Fifth Framework Programme of the EC. Led by CERN, MammoGrid involves the UK (the Universities of Oxford, Cambridge and the West of England, Bristol, plus the company Mirada Solutions of Oxford), and Italy (the Universities of Pisa and Sassari and the Hospitals in Udine and Torino). The aim of the project is, in light of emerging GRID technology, to develop a Europe-wide database of mammograms. The database will be used to investigate a set of important healthcare applications as well as the potential of the GRID to enable healthcare professionals throughout the EU to work together effectively. The contributions of the partners include building the GRID-database infrastructure, developing image processing and Computer Aided Detection techniques, and making the clinical evaluation. The first project meeting took place at CERN in Sept...

Quality Control in Mammography: Image Quality and Patient Doses

International Nuclear Information System (INIS)

Ciraj Bjelac, O.; Arandjic, D.; Boris Loncar, B.; Kosutic, D.

2008-01-01

Mammography is method of choice for early detection of breast cancer. The purpose of this paper is preliminary evaluation the mammography practice in Serbia, in terms of both quality control indicators, i.e. image quality and patient doses. The survey demonstrated considerable variations in technical parameters that affect image quality and patients doses. Mean glandular doses ranged from 0.12 to 2.8 mGy, while reference optical density ranged from 1.2 to 2.8. Correlation between image contrast and mean glandular doses was demonstrated. Systematic implementation of quality control protocol should provide satisfactory performance of mammography units and maintain satisfactory image quality and keep patient doses as low as reasonably practicable. (author)

CMOS cassette for digital upgrade of film-based mammography systems

Science.gov (United States)

Baysal, Mehmet A.; Toker, Emre

2006-03-01

While full-field digital mammography (FFDM) technology is gaining clinical acceptance, the overwhelming majority (96%) of the installed base of mammography systems are conventional film-screen (FSM) systems. A high performance, and economical digital cassette based product to conveniently upgrade FSM systems to FFDM would accelerate the adoption of FFDM, and make the clinical and technical advantages of FFDM available to a larger population of women. The planned FFDM cassette is based on our commercial Digital Radiography (DR) cassette for 10 cm x 10 cm field-of-view spot imaging and specimen radiography, utilizing a 150 micron columnar CsI(Tl) scintillator and 48 micron active-pixel CMOS sensor modules. Unlike a Computer Radiography (CR) cassette, which requires an external digitizer, our DR cassette transfers acquired images to a display workstation within approximately 5 seconds of exposure, greatly enhancing patient flow. We will present the physical performance of our prototype system against other FFDM systems in clinical use today, using established objective criteria such as the Modulation Transfer Function (MTF), Detective Quantum Efficiency (DQE), and subjective criteria, such as a contrast-detail (CD-MAM) observer performance study. Driven by the strong demand from the computer industry, CMOS technology is one of the lowest cost, and the most readily accessible technologies available for FFDM today. Recent popular use of CMOS imagers in high-end consumer cameras have also resulted in significant advances in the imaging performance of CMOS sensors against rivaling CCD sensors. This study promises to take advantage of these unique features to develop the first CMOS based FFDM upgrade cassette.

Preparing women for breast screening mammography: A feasibility study to determine the potential value of an on-line social network and information hub

International Nuclear Information System (INIS)

Robinson, L.; Griffiths, M.; Wray, J.; Ure, C.; Shires, G.; Stein-Hodgins, J.R.; Hill, C.; Hilton, B.

2015-01-01

This feasibility study explored the attitudes of women towards social media for support about breast screening mammography. It sought their ideas about what a dedicated breast screening hub or Digital Support Network (DSN) might comprise; how they would network with other women on the DSN; what format information might take; and whether a health professional should be available on the DSN. Data comprised 94 survey questionnaires and two focus groups; one comprised women in the breast screening population age group, the other was a younger group. A socio-ecological framework was used to identify key influencers and potential barriers for the implementation of a mammography DSN. The study identified issues related to three intersecting concepts which influenced women's behaviour: on-line conversations about health in general; on-line conversations about breast screening mammography and the culture of privacy which makes conversing about intimate health (either face to face or on-line) difficult. Also, the transient nature of the mammography episode (three yearly), could mean an on-line breast screening digital network is challenging to sustain. super-users’ may be needed to continue on-line conversations. The health professional was also seen as essential for moderating potential misinformation shared by women although the participants were also insistent that ‘truth’ be shared. - Highlights: • Ensure factual information is provided that is in textual format with images and video. • Provide option to network in private. • Develop health practitioners who can provide a balanced perspective in facilitating the sharing of true experiences. • Work with employers to implement organisational changes. • Target certain groups in more direct ways (i.e. those with lower self-efficacy in terms of on-line skills).

Beyond the mammography debate: a moderate perspective.

Science.gov (United States)

Kaniklidis, C

2015-06-01

After some decades of contention, one can almost despair and conclude that (paraphrasing) "the mammography debate you will have with you always." Against that sentiment, in this review I argue, after reflecting on some of the major themes of this long-standing debate, that we must begin to move beyond the narrow borders of claim and counterclaim to seek consensus on what the balance of methodologically sound and critically appraised evidence demonstrates, and also to find overlooked underlying convergences; after acknowledging the reality of some residual and non-trivial harms from mammography, to promote effective strategies for harm mitigation; and to encourage deployment of new screening modalities that will render many of the issues and concerns in the debate obsolete. To these ends, I provide a sketch of what this looking forward and beyond the current debate might look like, leveraging advantages from abbreviated breast magnetic resonance imaging technologies (such as the ultrafast and twist protocols) and from digital breast tomosynthesis-also known as three-dimensional mammography. I also locate the debate within the broader context of mammography in the real world as it plays out not for the disputants, but for the stakeholders themselves: the screening-eligible patients and the physicians in the front lines who are charged with enabling both the acts of screening and the facts of screening at their maximally objective and patient-accessible levels to facilitate informed decisions.

Dose measurements in mammography

International Nuclear Information System (INIS)

Kainberger, F.; Kallinger, W.

1977-01-01

Dose measurements at the mamma during mammography were carried out in the form of direct measurement with thermoluminescent dosimetry. Measurement was done for the in- and outcoming doses at the mamma, the dose exposure of the sternal region and the scattered rays above the symphysis, the latter as parameter for the genetic radiation exposure. As expected, the dose of the smooth radiation used for mammography showed a strong decrease at the outcome point in comparison with the income point. Surprisingly high was the scattered radiation in the sternal region. A corresponding protection by lead plates could be taken into consideration. Extremely low is the scattered radiation above the symphysis. Even measurements with the very sensitive calcium fluoride dosimeters did not reveal any practically important dose in the symphysis region. Most measurement values remained below the determinable dose of 0.3mR. Some maximal values varied in the range of 3-1 mR. (orig.) [de

Digital mammography and their developments; Digitale Mammografie und ihre Weiterentwicklung

Energy Technology Data Exchange (ETDEWEB)

Wienbeck, Susanne [Universitaetsmedizin Goettingen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Fischer, Uwe [Diagnostisches Brustzentrum Goettingen (Germany)

2015-09-15

At the present time digital mammography is a satisfactory breast diagnostic imaging in clinical as well as screening mammography in defined age groups. Nevertheless it shows beside the application of ionizing radiation in women with dense breasts limitations in the detection of non calcification breast cancers. Tomosynthesis, digital contrast-enhanced mammography and breast-CT with or without contrast media lead to better results. Especially the application of contrast media for the visualisation of the tumor angiogenesis is invariably superior to all other non-contrast imaging modalities. However, the excellent results of breast MRI will be probably accessible with none of the new procedures.

Comparison of 5-megapixel cathode ray tube monitors and 5-megapixel liquid crystal monitors for soft-copy reading in full-field digital mammography

International Nuclear Information System (INIS)

Schueller, Gerd; Schueller-Weidekamm, Claudia; Pinker, Katja; Memarsadeghi, Mazda; Weber, Michael; Helbich, Thomas H.

2010-01-01

Purpose: To retrospectively compare the image quality, lesion detection, and the diagnostic efficacy of 5-megapixel (MP) cathode ray tube monitors (CRTs) and 5-MP liquid crystal display monitors (LCDs) for soft-copy reading in full-field digital mammography (FFDM). Materials and methods: Informed consent was waived by the Institutional Review Board for the data analysis. A total of 220 cases were compared with two 5-MP (2048 x 2560 pixels) CRTs and two 5-MP (2048 x 2560 pixels) LCDs. Nine aspects of image quality (brightness, contrast, sharpness, noise, skin, fat, retromamillary space, glandular tissue, and detection of calcifications) were evaluated. In addition, the detection of breast lesions (mass, calcifications) and diagnostic efficacy, based on the BI-RADS classification, were correlated with histologic results (n = 70) and follow-up (n = 150). Results: Each aspect of the image quality was rated significantly better for 5-MP LCDs (p < 0.05) compared to the 5-MP CRTs. With 5-MP CRTs, 31 masses and 119 calcifications were detected, compared to 30 and 121 with 5-MP LCDs. The differences in diagnostic efficacy between 5-MP CRTs and 5-MP LCDs were not significant (p = 0.157) although 5-MP CRTs yielded two false-negative results. Both lesions were rated BI-RADS 3 with 5-MP CRTs. Both were invasive carcinomas at histology. The sensitivity, specificity, positive and negative predictive values, and accuracy were 0.966, 0.975, 0.933, 0.988, and 0.973 for 5-MP CRTs, compared to 1.0, 0.963, 0.903, 1.0, 0.973 for 5-MP LCDs. Conclusion: The image quality of 5-MP LCDs is significantly better than that of 5-MP CRTs for soft-copy reading in FFDM, based on histologic and follow-up correlation. However, lesion detection and diagnostic efficacy are comparable to 5-MP CRTs. The interpretation of the false-negative results suggests that the characterization of breast lesions with FFDM is not defined solely by the monitors, but is strongly influenced by the radiologist.

Digital breast tomosynthesis versus digital mammography: a clinical performance study

International Nuclear Information System (INIS)

Gennaro, Gisella; Baldan, Enrica; Bezzon, Elisabetta; Polico, Ilaria; Proietti, Alessandro; Toffoli, Aida; Toledano, Alicia; Di Maggio, Cosimo; La Grassa, Manuela; Pescarini, Luigi; Muzzio, Pier Carlo

2010-01-01

To compare the clinical performance of digital breast tomosynthesis (DBT) with that of full-field digital mammography (FFDM) in a diagnostic population. The study enrolled 200 consenting women who had at least one breast lesion discovered by mammography and/or ultrasound classified as doubtful or suspicious or probably malignant. They underwent tomosynthesis in one view [mediolateral oblique (MLO)] of both breasts at a dose comparable to that of standard screen-film mammography in two views [craniocaudal (CC) and MLO]. Images were rated by six breast radiologists using the BIRADS score. Ratings were compared with the truth established according to the standard of care and a multiple-reader multiple-case (MRMC) receiver-operating characteristic (ROC) analysis was performed. Clinical performance of DBT compared with that of FFDM was evaluated in terms of the difference between areas under ROC curves (AUCs) for BIRADS scores. Overall clinical performance with DBT and FFDM for malignant versus all other cases was not significantly different (AUCs 0.851 vs 0.836, p = 0.645). The lower limit of the 95% CI or the difference between DBT and FFDM AUCs was -4.9%. Clinical performance of tomosynthesis in one view at the same total dose as standard screen-film mammography is not inferior to digital mammography in two views. (orig.)

Mammography in breast screening and in the evaluation and management of breast cancer

International Nuclear Information System (INIS)

Onyesoh, C.N.

2006-01-01

This paper aims to discuss the importance of breast screening most especially amongst women above the age of 40 years.the limitation of the screening procedure is due to lack of special machines and power awareness campaigns. the application of Mammography and ultrasound in the examination of the breast and other breast imaging techniques will be considered in this paper. The paper will look at the indications for mammography, indications for breast ultrasound, signs of breast carcinoma on mammography, breast enlargement and also the need for breast ultrasound in cases of discrete Mammography

Mammography screening: A major issue in medicine.

Science.gov (United States)

Autier, Philippe; Boniol, Mathieu

2018-02-01

Breast cancer mortality is declining in most high-income countries. The role of mammography screening in these declines is much debated. Screening impacts cancer mortality through decreasing the incidence of number of advanced cancers with poor prognosis, while therapies and patient management impact cancer mortality through decreasing the fatality of cancers. The effectiveness of cancer screening is the ability of a screening method to curb the incidence of advanced cancers in populations. Methods for evaluating cancer screening effectiveness are based on the monitoring of age-adjusted incidence rates of advanced cancers that should decrease after the introduction of screening. Likewise, cancer-specific mortality rates should decline more rapidly in areas with screening than in areas without or with lower levels of screening but where patient management is similar. These two criteria have provided evidence that screening for colorectal and cervical cancer contributes to decreasing the mortality associated with these two cancers. In contrast, screening for neuroblastoma in children was discontinued in the early 2000s because these two criteria were not met. In addition, overdiagnosis - i.e. the detection of non-progressing occult neuroblastoma that would not have been life-threatening during the subject's lifetime - is a major undesirable consequence of screening. Accumulating epidemiological data show that in populations where mammography screening has been widespread for a long time, there has been no or only a modest decline in the incidence of advanced cancers, including that of de novo metastatic (stage IV) cancers at diagnosis. Moreover, breast cancer mortality reductions are similar in areas with early introduction and high penetration of screening and in areas with late introduction and low penetration of screening. Overdiagnosis is commonplace, representing 20% or more of all breast cancers among women invited to screening and 30-50% of screen

Eighteen cases of small breast cancer: a comparative study of mammography, CT scan and pathology

International Nuclear Information System (INIS)

Wu Yaopan; Lin Haogao; Cai Peiqiang; Ouyang Yi; Zhang Weizhang; Lu Bingui

2003-01-01

Objective: To improve the early diagnosis of breast cancer through a study of the mammography and CT findings of small breast cancer. Methods: The mammography and CT findings of 18 cases of small breast cancer (φ≤2.0 cm in diameter) were studied and compared with pathological results. Results: The diagnostic accuracy of CT and mammography was 83% and 61%, respectively. There was a statistical difference between both modalities (P<0.05), CT scan was superior to mammography. However, there was no difference between them when assessing the lesion arising in F-type breast. In detecting breast fine cluster of calcification, the sensitivity of mammography was better than CT scan. Conclusion: The patient suspected of small breast cancer should take mammography as the first evaluation. CT scan is reserved for the further investigation. The mammography combined with CT scan can improve the early diagnostic rate of breast cancer

Demonstration of the importance of a dedicated neutron beam monitoring system for BNCT facility

International Nuclear Information System (INIS)

Chao, Der-Sheng; Liu, Yuan-Hao; Jiang, Shiang-Huei

2016-01-01

The neutron beam monitoring system is indispensable to BNCT facility in order to achieve an accurate patient dose delivery. The neutron beam monitoring of a reactor-based BNCT (RB-BNCT) facility can be implemented through the instrumentation and control system of a reactor provided that the reactor power level remains constant during reactor operation. However, since the neutron flux in reactor core is highly correlative to complicated reactor kinetics resulting from such as fuel depletion, poison production, and control blade movement, some extent of variation may occur in the spatial distribution of neutron flux in reactor core. Therefore, a dedicated neutron beam monitoring system is needed to be installed in the vicinity of the beam path close to the beam exit of the RB-BNCT facility, where it can measure the BNCT beam intensity as closely as possible and be free from the influence of the objects present around the beam exit. In this study, in order to demonstrate the importance of a dedicated BNCT neutron beam monitoring system, the signals originating from the two in-core neutron detectors installed at THOR were extracted and compared with the three dedicated neutron beam monitors of the THOR BNCT facility. The correlation of the readings between the in-core neutron detectors and the BNCT neutron beam monitors was established to evaluate the improvable quality of the beam intensity measurement inferred by the in-core neutron detectors. In 29 sampled intervals within 16 days of measurement, the fluctuations in the mean value of the normalized ratios between readings of the three BNCT neutron beam monitors lay within 0.2%. However, the normalized ratios of readings of the two in-core neutron detectors to one of the BNCT neutron beam monitors show great fluctuations of 5.9% and 17.5%, respectively. - Highlights: • Two in-core neutron detectors and three BNCT neutron beam monitors were compared. • BNCT neutron beam monitors improve the stability in neutron

The Speed Reading Is in Disrepute: Advantages of Slow Reading for the Information Equilibrium

Science.gov (United States)

Tsvetkova, Milena I.

2017-01-01

The study is dedicated to the impact of the speed and the acceleration on the preservation of the information equilibrium and the ability for critical thinking in the active person. The methods about the fast reading training are subjected to a critical analysis. On the grounds of the theory for the information equilibrium and the philosophy of…

Assessment of the willingness of Australian radiographers in mammography to accept new responsibilities in role extension: Part two – qualitative analysis

International Nuclear Information System (INIS)

Moran, S.; Taylor, J.K.; Warren-Forward, H.

2013-01-01

Advanced practice in screening mammography has become widespread in the United Kingdom over the last 20 years, and Australian radiographers working in BreastScreen programs have shown interest in similar developments. Radiographers working in BreastScreen Australia were surveyed in order to capture their thoughts and perceptions on role extension. Questionnaires were circulated to radiographers working in BreastScreen Australia programs. Thematic analysis was used to analyze the open response questions to explore the advantages and disadvantages identified by the participants with respect to role expansion in screening mammography as well as any changes to their duties over the last decade. There were 253 responses to the survey and of those responses, 70% of radiographers shared their thoughts on role extension and 49% provided comments on changes in the workplace. The majority (61%) radiographers responding to the role extension question were concerned about potential problems associated with role extension; the biggest issues were that role extension should not be mandatory and that selection criteria for advanced practitioners should be stringent, with adequate time made available for training and study. The major change in the role of the radiographer has been the increased time dedicated to quality assurance tasks and administrative duties as well as more training required due to technological changes from film-screen to digital mammography. There is high interest in role extension by radiographers working in BreastScreen programs, provided that it is voluntary. The role of the radiographer within breast imaging in Australia is still evolving

Radiology workstation for mammography: preliminary observations, eyetracker studies, and design

Science.gov (United States)

Beard, David V.; Johnston, Richard E.; Pisano, Etta D.; Hemminger, Bradley M.; Pizer, Stephen M.

1991-07-01

For the last four years, the UNC FilmPlane project has focused on constructing a radiology workstation facilitating CT interpretations equivalent to those with film and viewbox. Interpretation of multiple CT studies was originally chosen because handling such large numbers of images was considered to be one of the most difficult tasks that could be performed with a workstation. The authors extend the FilmPlane design to address mammography. The high resolution and contrast demands coupled with the number of images often cross- compared make mammography a difficult challenge for the workstation designer. This paper presents the results of preliminary work with workstation interpretation of mammography. Background material is presented to justify why the authors believe electronic mammographic workstations could improve health care delivery. The results of several observation sessions and a preliminary eyetracker study of multiple-study mammography interpretations are described. Finally, tentative conclusions of what a mammographic workstation might look like and how it would meet clinical demand to be effective are presented.

XERG-mammography system: a solution to the dose-quality problem

Energy Technology Data Exchange (ETDEWEB)

Friedrich, M

1981-05-01

The XERG (Xonics-Electron-Radio-Graphy) system is the first ionographic system (High-Pressure-Gas-Iono-graphy) suitable for clinical application which became available for testing. The basic principle, the function and imaging qualities of the XERG system are described and first clinical experiences reported. The XERG mammogram is a transparent X-ray negative image, the image quality of which is characterized by good general image contrast, a moderate edge-effect and a high quantum-noise level but giving an extremely low dose rate (4.5% compared to screenless mammography film). Although the XERG quality is not satisfactory in contact technique, it yields results which are equal in quality, when using a 1.5-fold magnification technique, to the results obtained with screenless film mammography at one-tenth of the dose, and is superior to any commercially available film-screen system. Hence, in our opinion, the XERG mammography system is a step forward towards high-quality low-dose mammography.

[Hierarchy structuring for mammography technique by interpretive structural modeling method].

Science.gov (United States)

Kudo, Nozomi; Kurowarabi, Kunio; Terashita, Takayoshi; Nishimoto, Naoki; Ogasawara, Katsuhiko

2009-10-20

Participation in screening mammography is currently desired in Japan because of the increase in breast cancer morbidity. However, the pain and discomfort of mammography is recognized as a significant deterrent for women considering this examination. Thus quick procedures, sufficient experience, and advanced skills are required for radiologic technologists. The aim of this study was to make the point of imaging techniques explicit and to help understand the complicated procedure. We interviewed 3 technologists who were highly skilled in mammography, and 14 factors were retrieved by using brainstorming and the KJ method. We then applied Interpretive Structural Modeling (ISM) to the factors and developed a hierarchical concept structure. The result showed a six-layer hierarchy whose top node was explanation of the entire procedure on mammography. Male technologists were related to as a negative factor. Factors concerned with explanation were at the upper node. We gave attention to X-ray techniques and considerations. The findings will help beginners improve their skills.

A method to measure paddle and detector pressures and footprints in mammography

Energy Technology Data Exchange (ETDEWEB)

Hogg, Peter; Szczepura, Katy [University of Salford, Salford, Greater Manchester M6 6PU (United Kingdom); Darlington, Alison [Pennine Acute Hospital NHS Trust, Manchester M8 5RB (United Kingdom); Maxwell, Anthony [Royal Bolton Hospital NHS Foundation Trust, Bolton BL4 0JR (United Kingdom)

2013-04-15

Purpose: Compression is necessary in mammography to improve image quality and reduce radiation burden. Maximizing the amount of breast in contact with the image receptor (IR) is important. To achieve this, for the craniocaudal projection, there is no consensus within the literature regarding how the IR should be positioned relative to the inframammary fold (IMF). No information exists within the literature to describe how pressure balancing between IR and paddle, and IR breast footprint, might be optimized. This paper describes a novel method for measuring the respective pressures applied to the breast from the IR and the paddle and a method to simultaneously measure the breast footprints on the IR and the paddle. Methods: Using a deformable breast phantom and electronic pressure-sensitive mat, area and pressure readings were gathered from two mammography machines and four paddles at 60, 80, and 100 N with the IR positioned at -2, -1, 0, +1, and +2 cm relative to the IMF (60 combinations in total). Results: Paddle and IR footprints were calculated along with a uniformity index (UI). For all four paddle/machine/pressure combinations the greatest IR footprint was achieved at IMF +2 cm. The UI indicates that the best pressure/footprint balance is achieved at IMF +1 cm. Conclusions: The authors' method appears to be suited to measuring breast footprints and pressures on IR and paddle and a human female study is planned.

A method to measure paddle and detector pressures and footprints in mammography

International Nuclear Information System (INIS)

Hogg, Peter; Szczepura, Katy; Darlington, Alison; Maxwell, Anthony

2013-01-01

Purpose: Compression is necessary in mammography to improve image quality and reduce radiation burden. Maximizing the amount of breast in contact with the image receptor (IR) is important. To achieve this, for the craniocaudal projection, there is no consensus within the literature regarding how the IR should be positioned relative to the inframammary fold (IMF). No information exists within the literature to describe how pressure balancing between IR and paddle, and IR breast footprint, might be optimized. This paper describes a novel method for measuring the respective pressures applied to the breast from the IR and the paddle and a method to simultaneously measure the breast footprints on the IR and the paddle. Methods: Using a deformable breast phantom and electronic pressure-sensitive mat, area and pressure readings were gathered from two mammography machines and four paddles at 60, 80, and 100 N with the IR positioned at −2, −1, 0, +1, and +2 cm relative to the IMF (60 combinations in total). Results: Paddle and IR footprints were calculated along with a uniformity index (UI). For all four paddle/machine/pressure combinations the greatest IR footprint was achieved at IMF +2 cm. The UI indicates that the best pressure/footprint balance is achieved at IMF +1 cm. Conclusions: The authors’ method appears to be suited to measuring breast footprints and pressures on IR and paddle and a human female study is planned.

Using Computers for Intervention and Remediation of Severely Reading-Impaired Children in a University Literacy Clinic.

Science.gov (United States)

Balajthy, Ernest; Reuber, Kristin; Damon, Corrine J.

A study investigated software choices of graduate-level clinicians in a university reading clinic to determine computer use and effectiveness in literacy instruction. The clinic involved students of varying ability, ages 7-12, using 24 Power Macintosh computers equipped with "ClarisWorks,""Kid Pix,""Student Writing…

Results of a 2011 national questionnaire for investigation of mean glandular dose from mammography in Japan.

Science.gov (United States)

Asada, Y; Suzuki, S; Minami, K; Shirakawa, S

2014-03-01

Diagnostic reference levels (DRLs) for mammography have yet to be created in Japan. A national questionnaire investigation into radiographic conditions in Japan was carried out for the purpose of creating DRLs. Items investigated included the following: tube voltage; tube current; current-time product; source-image distance; craniocaudal view; automatic exposure control (AEC) settings; name of mammography unit; image receptor system (computed radiography (CR), flat panel detector (FPD), or film/screen (F/S)); and supported or unsupported monitor diagnosis (including monitor resolution). Estimation of the mean glandular dose (MGD) for mammography was performed and compared with previous investigations. The MGD was 1.58(0.48) mGy, which did not significantly differ from a 2007 investigation. In relation to image receptors, although no difference in average MGD values was observed between CR and FPD systems, F/S systems had a significantly decreased value compared to both CR and FPDs. Concerning digital systems (FPDs), the MGD value of the direct conversion system was significantly higher than the indirect conversion system. No significant difference in MGD value was evident concerning type of monitor diagnosis for either the CR or the FPD digital systems; however, hard copies were used more often in CR. No significant difference in the MGD value was found in relation to monitor resolution. This report suggests ways to lower the doses patients undergoing mammography receive in Japan, and serves as reference data for 4.2 cm compressed breast tissue of 50% composition DRLs. Furthermore, our findings suggest that further optimisation of FPD settings can promote a reduction in the MGD value.

Mechanistic modeling for mammography screening risks

International Nuclear Information System (INIS)

Bijwaard, Harmen

2008-01-01

Full text: Western populations show a very high incidence of breast cancer and in many countries mammography screening programs have been set up for the early detection of these cancers. Through these programs large numbers of women (in the Netherlands, 700.000 per year) are exposed to low but not insignificant X-ray doses. ICRP based risk estimates indicate that the number of breast cancer casualties due to mammography screening can be as high as 50 in the Netherlands per year. The number of lives saved is estimated to be much higher, but for an accurate calculation of the benefits of screening a better estimate of these risks is indispensable. Here it is attempted to better quantify the radiological risks of mammography screening through the application of a biologically based model for breast tumor induction by X-rays. The model is applied to data obtained from the National Institutes of Health in the U.S. These concern epidemiological data of female TB patients who received high X-ray breast doses in the period 1930-1950 through frequent fluoroscopy of their lungs. The mechanistic model that is used to describe the increased breast cancer incidence is based on an earlier study by Moolgavkar et al. (1980), in which the natural background incidence of breast cancer was modeled. The model allows for a more sophisticated extrapolation of risks to the low dose X-ray exposures that are common in mammography screening and to the higher ages that are usually involved. Furthermore, it allows for risk transfer to other (non-western) populations. The results have implications for decisions on the frequency of screening, the number of mammograms taken at each screening, minimum and maximum ages for screening and the transfer to digital equipment. (author)

Dose reduction through gridless technique in digital full-field mammography

International Nuclear Information System (INIS)

Diekmann, F.; Diekmann, S.; Berzeg, S.; Blick, U.; Fischer, T.; Hamm, B.

2003-01-01

Purpose: To determine the role of the scatter grid in digital full-field mammography with respect to image quality and dose and to compare the experimental results with initial clinical experience. Materials and Methods: A phantom consisting of 205 fields that enclose gold dots of different thickness and size (CD-Mam phantom, Medical Department, Nijmegen, Netherlands) was used for digital full-field mammography with the conventional grid module and a special gridless module. Four different breast thicknesses were simulated using Plexiglas as scatter material. First, the phantom was exposed at the parameter and dose settings automatically selected in each experimental setup (with and without grid). Subsequently, the phantom was exposed at the different simulated breast thicknesses using the gridless module in combination with the parameters automatically selected for the grid module. This was followed by a series of phantom mammograms obtained with the experimental setup reversed. The 16 mammograms were evaluated by 3 readers and the results compared considering breast thickness, radiation dose, and quality. The gridless module was used for preoperative labeling in 16 patients for comparison of mammograms obtained with and without a grid. Results: For the same entrance dose used in routine mammography, digital mammography without grid is superior to digital mammography with grid when performed on simulated thin breasts (Plexiglas less than 3 cm), with no difference found when performed on simulated large breasts. The advantages of gridless mammography are more pronounced at a markedly reduced entrance dose (identical parenchymal dose without and with grid using the dose automatically selected for the gridless module). This tendency is confirmed by the initial clinical comparison. (orig.) [de

Consequences of digital mammography in population-based breast cancer screening: initial changes and long-term impact on referral rates

Energy Technology Data Exchange (ETDEWEB)

Bluekens, Adriana M.J. [National Expert and Training Centre for Breast Cancer Screening, Nijmegen (Netherlands); St. Elisabeth Hospital, Department of Radiology, Tilburg (Netherlands); Karssemeijer, Nico [Radboud University Nijmegen Medical Centre, Department of Radiology, Nijmegen (Netherlands); Beijerinck, David; Deurenberg, Jan J.M. [Preventicon Screening Centre/Mid-West, Utrecht (Netherlands); Engen, Ruben E. van [National Expert and Training Centre for Breast Cancer Screening, Nijmegen (Netherlands); Broeders, Mireille J.M. [National Expert and Training Centre for Breast Cancer Screening, Nijmegen (Netherlands); Radboud University Nijmegen Medical Centre, Department of Epidemiology, Biostatistics and HTA, Nijmegen (Netherlands); Heeten, Gerard J. den [National Expert and Training Centre for Breast Cancer Screening, Nijmegen (Netherlands); Academic Medical Centre (AMC), Department of Radiology, Amsterdam (Netherlands)

2010-09-15

To investigate the referral pattern after the transition to full-field digital mammography (FFDM) in a population-based breast cancer screening programme. Preceding the nationwide digitalisation of the Dutch screening programme, an FFDM feasibility study was conducted. Detection and referral rates for FFDM and screen-film mammography (SFM) were compared for first and subsequent screens. Furthermore, radiological characteristics of referrals in digital screening were assessed. A total of 312,414 screening mammograms were performed (43,913 digital and 268,501 conventional), with 4,473 consecutive referrals (966 following FFDM). Initially the FFDM referral rate peaked, and many false-positive results were noted as a consequence of pseudolesions and increased detection of (benign) microcalcifications. A higher overall referral rate was observed in FFDM screening in both first and subsequent examinations (p <.001), with a significant increase in cancer detection (p =.010). As a result of initial inexperience with digital screening images implementing FFDM in a population-based breast cancer screening programme may lead to a strong, but temporary increase in referral. Dedicated training in digital screening for radiographers and screening radiologists is therefore recommended. Referral rates decrease and stabilise (learning curve effect) at a higher level than in conventional screening, yet with significantly enhanced cancer detection. (orig.)

Consequences of digital mammography in population-based breast cancer screening: initial changes and long-term impact on referral rates.

Science.gov (United States)

Bluekens, Adriana M J; Karssemeijer, Nico; Beijerinck, David; Deurenberg, Jan J M; van Engen, Ruben E; Broeders, Mireille J M; den Heeten, Gerard J

2010-09-01

To investigate the referral pattern after the transition to full-field digital mammography (FFDM) in a population-based breast cancer screening programme. Preceding the nationwide digitalisation of the Dutch screening programme, an FFDM feasibility study was conducted. Detection and referral rates for FFDM and screen-film mammography (SFM) were compared for first and subsequent screens. Furthermore, radiological characteristics of referrals in digital screening were assessed. A total of 312,414 screening mammograms were performed (43,913 digital and 268,501 conventional), with 4,473 consecutive referrals (966 following FFDM). Initially the FFDM referral rate peaked, and many false-positive results were noted as a consequence of pseudolesions and increased detection of (benign) microcalcifications. A higher overall referral rate was observed in FFDM screening in both first and subsequent examinations (p < .001), with a significant increase in cancer detection (p = .010). As a result of initial inexperience with digital screening images implementing FFDM in a population-based breast cancer screening programme may lead to a strong, but temporary increase in referral. Dedicated training in digital screening for radiographers and screening radiologists is therefore recommended. Referral rates decrease and stabilise (learning curve effect) at a higher level than in conventional screening, yet with significantly enhanced cancer detection.

Consequences of digital mammography in population-based breast cancer screening: initial changes and long-term impact on referral rates

International Nuclear Information System (INIS)

Bluekens, Adriana M.J.; Karssemeijer, Nico; Beijerinck, David; Deurenberg, Jan J.M.; Engen, Ruben E. van; Broeders, Mireille J.M.; Heeten, Gerard J. den

2010-01-01

To investigate the referral pattern after the transition to full-field digital mammography (FFDM) in a population-based breast cancer screening programme. Preceding the nationwide digitalisation of the Dutch screening programme, an FFDM feasibility study was conducted. Detection and referral rates for FFDM and screen-film mammography (SFM) were compared for first and subsequent screens. Furthermore, radiological characteristics of referrals in digital screening were assessed. A total of 312,414 screening mammograms were performed (43,913 digital and 268,501 conventional), with 4,473 consecutive referrals (966 following FFDM). Initially the FFDM referral rate peaked, and many false-positive results were noted as a consequence of pseudolesions and increased detection of (benign) microcalcifications. A higher overall referral rate was observed in FFDM screening in both first and subsequent examinations (p <.001), with a significant increase in cancer detection (p =.010). As a result of initial inexperience with digital screening images implementing FFDM in a population-based breast cancer screening programme may lead to a strong, but temporary increase in referral. Dedicated training in digital screening for radiographers and screening radiologists is therefore recommended. Referral rates decrease and stabilise (learning curve effect) at a higher level than in conventional screening, yet with significantly enhanced cancer detection. (orig.)

Free software for performing physical analysis of systems for digital radiography and mammography

Energy Technology Data Exchange (ETDEWEB)

Donini, Bruno; Lanconelli, Nico, E-mail: nico.lanconelli@unibo.it [Alma Mater Studiorum, Department of Physics and Astronomy, University of Bologna, Bologna 40127 (Italy); Rivetti, Stefano [Fisica Medica, Ospedale di Sassuolo S.p.A., Sassuolo 41049 (Italy); Bertolini, Marco [Medical Physics Unit, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, Reggio Emilia 42123 (Italy)

2014-05-15

Purpose: In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. Methods: The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. Results: The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. Conclusions: This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online ( http://www.medphys.it/downloads.htm ). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement.

Free software for performing physical analysis of systems for digital radiography and mammography.

Science.gov (United States)

Donini, Bruno; Rivetti, Stefano; Lanconelli, Nico; Bertolini, Marco

2014-05-01

In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online (www.medphys.it/downloads.htm). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement.

Free software for performing physical analysis of systems for digital radiography and mammography

International Nuclear Information System (INIS)

Donini, Bruno; Lanconelli, Nico; Rivetti, Stefano; Bertolini, Marco

2014-01-01

Purpose: In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. Methods: The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. Results: The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. Conclusions: This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online ( http://www.medphys.it/downloads.htm ). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement

Comparison between indicators dosimetric released by teams and estimates by dosimetry TLD in the mammography of the Hospital Universitario 12 de Octubre

International Nuclear Information System (INIS)

Rot San Juan, M. J.; Martinez Gomez, L. C.; Gilarranz Moreno, R.; Milanes Gaillet, A. I.; Adaimi Hernandez, P.; Delgado rodriguez, J. M.

2013-01-01

With the incorporation of new technology, computers have indicators of dose for this magnitude. In this work we will compare to the mammography in our area the measure with the DSE TLD values thrown by the equipment. (Author)

BI-RADS categorisation of 2708 consecutive nonpalpable breast lesions in patients referred to a dedicated breast care unit

International Nuclear Information System (INIS)

Hamy, A.S.; Giacchetti, S.; Cuvier, C.; Perret, F.; Bonfils, S.; Charveriat, P.; Hocini, H.; Espie, M.; Albiter, M.; Bazelaire, C. de; Roquancourt, A. de

2012-01-01

To determine the malignancy rate of nonpalpable breast lesions, categorised according to the Breast Imaging Reporting and Data System (BI-RADS) classification in the setting of a Breast Care Unit. All nonpalpable breast lesions from consecutive patients referred to a dedicated Breast Care Unit were prospectively reviewed and classified into 5 BI-RADS assessment categories (0, 2, 3, 4, and 5). A total of 2708 lesions were diagnosed by mammography (71.6%), ultrasound (8.7%), mammography and ultrasound (19.5%), or MRI (0.2%). The distribution of the lesions by BI-RADS category was: 152 in category 0 (5.6%), 56 in category 2 (2.1%), 742 in category 3 (27.4%), 1523 in category 4 (56.2%) and 235 in category 5 (8.7%). Histology revealed 570 malignant lesions (32.9%), 152 high-risk lesions (8.8%), and 1010 benign lesions (58.3%). Malignancy was detected in 17 (2.3%) category 3 lesions, 364 (23.9%) category 4 lesions and 185 (78.7%) category 5 lesions. Median follow-up was 36.9 months. This pragmatic study reflects the assessment and management of breast impalpable abnormalities referred for care to a specialized Breast Unit. Multidisciplinary evaluation with BI-RADS classification accurately predicts malignancy, and reflects the quality of management. This assessment should be encouraged in community practice appraisal. (orig.)

Screening for breast cancer with mammography

International Nuclear Information System (INIS)

Sickles, E.A.

1991-01-01

Mammography is generally accepted as a useful problem-solving clinical tool in characterizing known breast lesions, so that appropriate and timely treatment can be given. However, it remains grossly underutilized at what it does best: screening. The major strengths of mammography are (a) its ability to detect breast cancer at a smaller, potentially more curable stage than any other examination, and (b) its proved efficacy in reducing breast cancer mortality in asymptomatic women aged 40-74. If, as has recently been estimated, screening with mammography and physical examination can be expected to lower breast cancer deaths by 40%-50% among those actually examined (13), then the lives of almost 20,000 U.S. women might be saved each year if screening were to become very widely used. The challenges of the next decade are clear, to mount much more effective campaigns to educate physicians and lay women about the life-saving benefits of breast cancer screening, to devise increasingly effective and lower cost screening strategies, to further improve the current high quality of mammographic imaging despite its increasing proliferation, and to train large numbers of breast imaging specialists to guarantee that the growing case load of screening and problem-solving mammograms is interpreted with a very high level of skill

Radiation doses in mammography as planning parameters for premature breast cancer tracking programs

International Nuclear Information System (INIS)

Souza Ferreira, Rubemar de.

1994-01-01

Radiation doses are the main parameters applied to the evaluation of mammographic radiological impact. This study, for a sample of 407 women, were analyzed, through the thermoluminescent dosimetry, radiation doses in the surface of skin and glandular absorbed doses for cranio-caudal view. The results show the presence of a large dose range to the same mammographic procedure, which, analyzed enclosed with 585 facilities, suggest be necessary the standardization of the mammographic technique. From that results, with the additive model, the excess of breast cancer (radioinduced) and lifetime loss risk, for age groups between 30 and 70 years were estimated. Is demonstrated that the benefits from dedicated mammography, overcome the relationship among the epidemiological aspects of breast cancer and ionizing radiation as an harmful agent, which may show an important correlation for large exposed populations, point out the importance of the continuous risk and benefit evaluation to the new technologies introduced. (author). 86 refs., 40 figs., 14 tabs

Is Short-Interval Mammography Necessary After Breast Conservation Surgery and Radiation Treatment in Breast Cancer Patients?

International Nuclear Information System (INIS)

Hymas, Richard V.; Gaffney, David K.; Parkinson, Brett T.; Belnap, Thomas W.; Sause, William T.

2012-01-01

Purpose: The optimum timing and frequency of mammography in breast cancer patients after breast-conserving therapy (BCT) are controversial. The American Society of Clinical Oncology recommends the first posttreatment mammogram 1 year after diagnosis but no earlier than 6 months after completion of radiotherapy. The National Comprehensive Cancer Network recommends annual mammography. Intermountain Healthcare currently follows a more frequent mammography schedule during the first 2 years in BCT patients. This retrospective study was undertaken to determine the cancer yield mammography during the first 2 years after BCT. Methods and Materials: 1,435 patients received BCT at Intermountain Healthcare between 2003 and 2007, inclusive. Twenty-three patients had bilateral breast cancer (1,458 total breasts). Patients were followed up for 24 months after diagnosis. The 1- and 2-year mammography yields were determined and compared with those of the general screening population. Results: 1,079 breasts had mammography at less than 1 year, and two ipsilateral recurrences (both noninvasive) were identified; 1,219 breasts had mammography during the second year, and nine recurrences (three invasive, six noninvasive) were identified. Of the 11 ipsilateral recurrences during the study, three presented with symptoms and eight were identified by mammography alone. The mammography yield was 1.9 cancers per 1,000 breasts the first year and 4.9 per 1,000 the second year. Conclusions: These data demonstrate that the mammography yield during the first 2 years after BCT is not greater than that in the general population, and they support the policy for initiating followup mammography at 1 year after BCT.

Early intervention with children of dyslexic parents: Effects of computer-based reading instruction at home on literacy acquisition

NARCIS (Netherlands)

Regtvoort, A.G.F.M.; van der Leij, A.

2007-01-01

The hereditary basis of dyslexia makes it possible to identify children at risk early on. Pre-reading children genetically at risk received during 14 weeks a home- and computer-based training in phonemic awareness and letter-sound relationships in the context of reading instruction. At posttest

Hidden costs of low-cost screening mammography

International Nuclear Information System (INIS)

Cyrlak, D.

1987-01-01

Twenty-two hundred women in Orange County, California, took part in a low-cost mammography screening project sponsored by the American Cancer Society and the KCBS-TV. Patients were followed up by telephone and questioned about actual costs incurred as a result of screening mammography, including costs of repeated and follow-up mammograms, US examinations and surgical consultations. The total number of biopsies, cancers found, and the costs involved were investigated. The authors' results suggest that particularly in centers with a high positive call rate, the cost of screening mammograms accounts for only a small proportion of the medical costs