WorldWideScience

Sample records for digital mammographic unit

  1. Impact of digitalization of mammographic units on average glandular doses in the Flemish Breast Cancer Screening Program

    OpenAIRE

    De Hauwere, An; Thierens, Hubert

    2012-01-01

    The impact of digitalization on the average glandular doses in 49 mammographic units participating in the Flemish Breast Cancer Screening Program was studied. Screen-film was changed to direct digital radiography and computed radiography in 25 and 24 departments respectively. Average glandular doses were calculated before and after digitalization for different PMMA-phantom thicknesses and for groups of 50 successive patients. For the transition from screen-film to computed radiography both ph...

  2. Advanced techniques in digital mammographic images recognition

    International Nuclear Information System (INIS)

    Aliu, R. Azir

    2011-01-01

    Computer Aided Detection and Diagnosis is used in digital radiography as a second thought in the process of determining diagnoses, which reduces the percentage of wrong diagnoses of the established interpretation of mammographic images. The issues that are discussed in the dissertation are the analyses and improvement of advanced technologies in the field of artificial intelligence, more specifically in the field of machine learning for solving diagnostic problems and automatic detection of speculated lesions in digital mammograms. The developed of SVM-based ICAD system with cascade architecture for analyses and comparison mammographic images in both projections (CC and MLO) gives excellent result for detection and masses and microcalcifications. In order to develop a system with optimal performances of sensitivity, specificity and time complexity, a set of relevant characteristics need to be created which will show all the pathological regions that might be present in the mammographic image. The structure of the mammographic image, size and the large number of pathological structures in this area are the reason why the creation of a set of these features is necessary for the presentation of good indicators. These pathological structures are a real challenge today and the world of science is working in that direction. The doctoral dissertation showed that the system has optimal results, which are confirmed by experts, and institutions, which are dealing with these same issues. Also, the thesis presents a new approach for automatic identification of regions of interest in the mammographic image where regions of interest are automatically selected for further processing mammography in cases when the number of examined patients is higher. Out of 480 mammographic images downloaded from MIAS database and tested with ICAD system the author shows that, after separation and selection of relevant features of ICAD system the accuracy is 89.7% (96.4% for microcalcifications

  3. Image quality analysis of digital mammographic equipments

    Energy Technology Data Exchange (ETDEWEB)

    Mayo, P.; Pascual, A.; Verdu, G. [Valencia Univ. Politecnica, Chemical and Nuclear Engineering Dept. (Spain); Rodenas, F. [Valencia Univ. Politecnica, Applied Mathematical Dept. (Spain); Campayo, J.M. [Valencia Univ. Hospital Clinico, Servicio de Radiofisica y Proteccion Radiologica (Spain); Villaescusa, J.I. [Hospital Clinico La Fe, Servicio de Proteccion Radiologica, Valencia (Spain)

    2006-07-01

    The image quality assessment of a radiographic phantom image is one of the fundamental points in a complete quality control programme. The good functioning result of all the process must be an image with an appropriate quality to carry out a suitable diagnostic. Nowadays, the digital radiographic equipments are replacing the traditional film-screen equipments and it is necessary to update the parameters to guarantee the quality of the process. Contrast-detail phantoms are applied to digital radiography to study the threshold contrast detail sensitivity at operation conditions of the equipment. The phantom that is studied in this work is C.D.M.A.M. 3.4, which facilitates the evaluation of image contrast and detail resolution. One of the most extended indexes to measure the image quality in an objective way is the Image Quality Figure (I.Q.F.). This parameter is useful to calculate the image quality taking into account the contrast and detail resolution of the image analysed. The contrast-detail curve is useful as a measure of the image quality too, because it is a graphical representation in which the hole thickness and diameter are plotted for each contrast-detail combination detected in the radiographic image of the phantom. It is useful for the comparison of the functioning of different radiographic image systems, for phantom images under the same exposition conditions. The aim of this work is to study the image quality of different images contrast-detail phantom C.D.M.A.M. 3.4, carrying out the automatic detection of the contrast-detail combination and to establish a parameter which characterize in an objective way the mammographic image quality. This is useful to compare images obtained at different digital mammographic equipments to study the functioning of the equipments. (authors)

  4. Image quality analysis of digital mammographic equipments

    International Nuclear Information System (INIS)

    Mayo, P.; Pascual, A.; Verdu, G.; Rodenas, F.; Campayo, J.M.; Villaescusa, J.I.

    2006-01-01

    The image quality assessment of a radiographic phantom image is one of the fundamental points in a complete quality control programme. The good functioning result of all the process must be an image with an appropriate quality to carry out a suitable diagnostic. Nowadays, the digital radiographic equipments are replacing the traditional film-screen equipments and it is necessary to update the parameters to guarantee the quality of the process. Contrast-detail phantoms are applied to digital radiography to study the threshold contrast detail sensitivity at operation conditions of the equipment. The phantom that is studied in this work is C.D.M.A.M. 3.4, which facilitates the evaluation of image contrast and detail resolution. One of the most extended indexes to measure the image quality in an objective way is the Image Quality Figure (I.Q.F.). This parameter is useful to calculate the image quality taking into account the contrast and detail resolution of the image analysed. The contrast-detail curve is useful as a measure of the image quality too, because it is a graphical representation in which the hole thickness and diameter are plotted for each contrast-detail combination detected in the radiographic image of the phantom. It is useful for the comparison of the functioning of different radiographic image systems, for phantom images under the same exposition conditions. The aim of this work is to study the image quality of different images contrast-detail phantom C.D.M.A.M. 3.4, carrying out the automatic detection of the contrast-detail combination and to establish a parameter which characterize in an objective way the mammographic image quality. This is useful to compare images obtained at different digital mammographic equipments to study the functioning of the equipments. (authors)

  5. Radiologists' preferences for digital mammographic display. The International Digital Mammography Development Group.

    Science.gov (United States)

    Pisano, E D; Cole, E B; Major, S; Zong, S; Hemminger, B M; Muller, K E; Johnston, R E; Walsh, R; Conant, E; Fajardo, L L; Feig, S A; Nishikawa, R M; Yaffe, M J; Williams, M B; Aylward, S R

    2000-09-01

    To determine the preferences of radiologists among eight different image processing algorithms applied to digital mammograms obtained for screening and diagnostic imaging tasks. Twenty-eight images representing histologically proved masses or calcifications were obtained by using three clinically available digital mammographic units. Images were processed and printed on film by using manual intensity windowing, histogram-based intensity windowing, mixture model intensity windowing, peripheral equalization, multiscale image contrast amplification (MUSICA), contrast-limited adaptive histogram equalization, Trex processing, and unsharp masking. Twelve radiologists compared the processed digital images with screen-film mammograms obtained in the same patient for breast cancer screening and breast lesion diagnosis. For the screening task, screen-film mammograms were preferred to all digital presentations, but the acceptability of images processed with Trex and MUSICA algorithms were not significantly different. All printed digital images were preferred to screen-film radiographs in the diagnosis of masses; mammograms processed with unsharp masking were significantly preferred. For the diagnosis of calcifications, no processed digital mammogram was preferred to screen-film mammograms. When digital mammograms were preferred to screen-film mammograms, radiologists selected different digital processing algorithms for each of three mammographic reading tasks and for different lesion types. Soft-copy display will eventually allow radiologists to select among these options more easily.

  6. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    International Nuclear Information System (INIS)

    Annovazzi, A.; Amendolia, S.R.; Bigongiari, A.; Bisogni, M.G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Colombo, F.; Delogu, P.; Fantacci, M.E.; Gilberti, A.; Lanzieri, C.; Lavagna, S.; Novelli, M.; Passuello, G.; Paternoster, G.; Pieracci, M.; Poletti, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Testa, A.; Venturelli, L.

    2007-01-01

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm 2 therefore to cover the typical irradiation field used in mammography (18x24 cm 2 ), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma 'La Sapienza', Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%

  7. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    Science.gov (United States)

    Annovazzi, A.; Amendolia, S. R.; Bigongiari, A.; Bisogni, M. G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Colombo, F.; Delogu, P.; Fantacci, M. E.; Gilberti, A.; Lanzieri, C.; Lavagna, S.; Novelli, M.; Passuello, G.; Paternoster, G.; Pieracci, M.; Poletti, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Testa, A.; Venturelli, L.

    2007-06-01

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm 2 therefore to cover the typical irradiation field used in mammography (18×24 cm 2), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma "La Sapienza", Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%.

  8. Quality Control and Dosimetry in Mammographic Units in Greece

    Energy Technology Data Exchange (ETDEWEB)

    Flioni-Vysa, A; Xenofos, S; Stamatelatos, E; Georgolopoulou, P [Department of Medical Physics, Saint Savvas Hospital, 171 Alexandras Avenue, Athens 115 22, (Greece)

    1994-12-31

    Quality control measurements have been carried out on 29 mammographic units. It was found that a large percentage of users obtained Optical Densities outside the recommended values. Resolution under routine conditions was below the limit of 14 lp/mm in about 50% of the units. The skin entrance dose was in a few cases in excess of 10 micro Gray, but the mean value was well below this upper limit. Analysis of the results obtained has indicated that proper calibration of kilo voltage panel indications and automatic exposure control systems is of outmost importance and should be performed regularly. (authors). 11 refs, 2 figs 3 tabs.

  9. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    Energy Technology Data Exchange (ETDEWEB)

    Annovazzi, A. [LABEN S.p.A., Vimodrone-Milan (Italy); Amendolia, S.R. [Str. Dip. di Matematica e Fisica dell' Universita, Sassari and Sezione I.N.F.N., Pisa (Italy); Bigongiari, A. [CAEN S.p.A., Viareggio-Lucca (Italy); Bisogni, M.G. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Catarsi, F. [CAEN S.p.A., Viareggio-Lucca (Italy); Cesqui, F. [AMS S.p.A, Rome (Italy); Cetronio, A. [AMS S.p.A, Rome (Italy); Colombo, F. [LABEN S.p.A., Vimodrone-Milan (Italy); Delogu, P. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Fantacci, M.E. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Gilberti, A. [LABEN S.p.A., Vimodrone-Milan (Italy); Lanzieri, C. [AMS S.p.A, Rome (Italy); Lavagna, S. [AMS S.p.A, Rome (Italy); Novelli, M. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Passuello, G. [CAEN S.p.A., Viareggio-Lucca (Italy); Paternoster, G. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Pieracci, M. [CAEN S.p.A., Viareggio-Lucca (Italy); Poletti, M. [LABEN S.p.A., Vimodrone-Milan (Italy); Quattrocchi, M. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Rosso, V. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Stefanini, A. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy)]. E-mail: arnaldo.stefanini@pi.infn.it; Testa, A. [CAEN S.p.A., Viareggio-Lucca (Italy); Venturelli, L. [AMS S.p.A, Rome (Italy)

    2007-06-11

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm{sup 2} therefore to cover the typical irradiation field used in mammography (18x24 cm{sup 2}), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma 'La Sapienza', Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%.

  10. Digital imaging improves upright stereotactic core biopsy of mammographic microcalcifications

    International Nuclear Information System (INIS)

    Whitlock, J.P.L.; Evans, A.J.; Burrell, H.C.; Pinder, S.E.; Ellis, I.O.; Blamey, R.W.; Wilson, A.R.M.

    2000-01-01

    AIM: This comparative study was carried out to assess the effect of using digital images compared to conventional film-screen mammography on the accuracy of core biopsy of microcalcifications using upright stereotactic equipment. MATERIALS AND METHODS: The biopsy results from a consecutive series of 104 upright stereotactic 14-gauge core biopsies performed with conventional X-ray (Group A) were compared with 40 biopsies carried out using stereotaxis with digital imaging (Group B). In all cases specimen radiography was performed and analysed for the presence of calcifications. Pathological correlation was then carried out with needle and surgical histology. RESULTS: The use of digital add-on equipment increased the radiographic calcification retrieval rate from 55 to 85% (P < 0.005). The absolute sensitivity of core biopsy in pure ductal carcinoma in situ (DCIS) cases rose from 34 to 69% (P < 0.03), with the complete sensitivity increasing from 52 to 94% (P < 0.005). For DCIS with or without an invasive component the absolute sensitivity rose from 41 to 67% (P = 0.052), while the complete sensitivity was 59% before and 86% after the introduction of digital imaging (P < 0.04). CONCLUSION: Digital equipment improves the performance of upright stereotactic core biopsy of microcalcifications, giving a significantly increased success rate in accurately obtaining calcifications. This leads to an improvement in absolute and complete sensitivity of core biopsy when diagnosing DCIS. Whitlock, J.P.L. (2000)

  11. 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.)

  12. Impact of full field digital mammography on the classification and mammographic characteristics of interval breast cancers

    Energy Technology Data Exchange (ETDEWEB)

    Knox, Mark, E-mail: marktknox@gmail.com; O’Brien, Angela, E-mail: angelaobrien@doctors.org.uk; Szabó, Endre, E-mail: endrebacsi@freemail.hu; Smith, Clare S., E-mail: csmith@mater.ie; Fenlon, Helen M., E-mail: helen.fenlon@cancerscreening.ie; McNicholas, Michelle M., E-mail: michelle.mcnicholas@cancerscreening.ie; Flanagan, Fidelma L., E-mail: fidelma.flanagan@cancerscreening.ie

    2015-06-15

    Highlights: • Digital mammography has changed the presentation of interval breast cancer. • Less interval breast cancers are associated with microcalcifications following FFDM. • Interval breast cancer audit remains a key feature of any breast screening program. - Abstract: Objective: Full field digital mammography (FFDM) is increasingly replacing screen film mammography (SFM) in breast screening programs. Interval breast cancers are an issue in all screening programs and the purpose of our study is to assess the impact of FFDM on the classification of interval breast cancers at independent blind review and to compare the mammographic features of interval cancers at FFDM and SFM. Materials and methods: This study included 138 cases of interval breast cancer, 76 following an FFDM screening examination and 62 following screening with SFM. The prior screening mammogram was assessed by each of five consultant breast radiologists who were blinded to the site of subsequent cancer. Subsequent review of the diagnostic mammogram was performed and cases were classified as missed, minimal signs, occult or true interval. Mammographic features of the interval cancer at diagnosis and any abnormality identified on the prior screening mammogram were recorded. Results: The percentages of cancers classified as missed at FFDM and SFM did not differ significantly, 10.5% (8 of 76) at FFDM and 8.1% (5 of 62) at SFM (p = .77). There were significantly less interval cancers presenting as microcalcifications (alone or in association with another abnormality) following screening with FFDM, 16% (12 of 76) than following a SFM examination, 32% (20 of 62) (p = .02). Conclusion: Interval breast cancers continue to pose a problem at FFDM. The switch to FFDM has changed the mammographic presentation of interval breast cancer, with less interval cancers presenting in association with microcalcifications.

  13. Impact of full field digital mammography on the classification and mammographic characteristics of interval breast cancers

    International Nuclear Information System (INIS)

    Knox, Mark; O’Brien, Angela; Szabó, Endre; Smith, Clare S.; Fenlon, Helen M.; McNicholas, Michelle M.; Flanagan, Fidelma L.

    2015-01-01

    Highlights: • Digital mammography has changed the presentation of interval breast cancer. • Less interval breast cancers are associated with microcalcifications following FFDM. • Interval breast cancer audit remains a key feature of any breast screening program. - Abstract: Objective: Full field digital mammography (FFDM) is increasingly replacing screen film mammography (SFM) in breast screening programs. Interval breast cancers are an issue in all screening programs and the purpose of our study is to assess the impact of FFDM on the classification of interval breast cancers at independent blind review and to compare the mammographic features of interval cancers at FFDM and SFM. Materials and methods: This study included 138 cases of interval breast cancer, 76 following an FFDM screening examination and 62 following screening with SFM. The prior screening mammogram was assessed by each of five consultant breast radiologists who were blinded to the site of subsequent cancer. Subsequent review of the diagnostic mammogram was performed and cases were classified as missed, minimal signs, occult or true interval. Mammographic features of the interval cancer at diagnosis and any abnormality identified on the prior screening mammogram were recorded. Results: The percentages of cancers classified as missed at FFDM and SFM did not differ significantly, 10.5% (8 of 76) at FFDM and 8.1% (5 of 62) at SFM (p = .77). There were significantly less interval cancers presenting as microcalcifications (alone or in association with another abnormality) following screening with FFDM, 16% (12 of 76) than following a SFM examination, 32% (20 of 62) (p = .02). Conclusion: Interval breast cancers continue to pose a problem at FFDM. The switch to FFDM has changed the mammographic presentation of interval breast cancer, with less interval cancers presenting in association with microcalcifications

  14. 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.)

  15. Comparative study on mammographic findings between conventional mammography and digital mammography

    International Nuclear Information System (INIS)

    Gonzalez Calle, Aurelio; Saldarriaga Jaramillo, Ximena; Zapata Walliser, Luz Estela; Mejia Restrepo, Jorge Hernando; Arango Martinez, Adriana; Velez Arango, Jorge Mario

    2007-01-01

    We performed conventional-film mammograms in 180 patients between 35 and 6 years and additionally, we added 2 digital CR technique images to each patient, either craneocaudal (90 patients) or oblique (90 patients). All images were interpreted independently by four radiologists for a total of 720 evaluations, who compared film versus digital images through a 5 mega pixel monitor (soft-copy), using a score scale using the following parameters: mass visualization, detection of micro-calcifications, architectural distortion, visibility of the skin line, and image sharpness and noise. Additionally the tissue density was classified as well as the BIRADS score. The data was processed with the Teleform program and analyzed by de SPSSS program. Results: 52.6% of the micro-calcifications were equally visualized with both systems, in 13.5% of the cases they were better visualized with digital mammography. Similarly, in 50% of the cases, the skin line was better visualized with the digital CR modality. Conclusion: the sharpness of the image was also better seen with the digital CR technique in 48.2%. On the contrary, more noise was seen in digital CR images (63%). digital mammography is a diagnostic alternative that can improve mammographic findings detection and finally become a useful tool in breast cancer diagnosis

  16. 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.

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

    International Nuclear Information System (INIS)

    Chon, Kwon Su; Park, Jeong Gon; Son, Hyun Hwa; Kang, Sung Hoon; Park, Seong Hoon; Kim, Hye Won; Kim, Hun Soo; Yoon, Kwon Ha

    2009-01-01

    To evaluate the efficacy for spatial resolution and radiation dose of a small-field digital mammographic imaging system using parabolic polycapillary optics. We developed a small-field digital mammographic imaging system composed of a CCD (charge coupled device) detector and an Xray source coupled with parabolic polycapillary optics. The spatial resolution and radiation dose according to various filters were evaluated for a small-field digital mammographic imaging system. The images of a test standard phantom and breast cancer tissue sample were obtained. The small-field digital mammographic imaging system had spatial resolutions of 12 lp/mm with molybdenum and rhodium filters with a 25-μm thickness. With a thicker molybdenum filter (100 μm thick), the system had a higher spatial resolution of 11 lp/mm and contrast of 0.48. The radiation dose for a rhodium filter with a 25-μm thickness was 0.13 mGy within a 10-mm-diameter local field. A larger field image greater than 10 mm in diameter could be obtained by scanning an object. On the small-field mammographic imaging system, microcalcifications of breast cancer tissue were clearly observed. A small-field digital mammographic imaging system with parabolic polycapillary optics may be a useful diagnostic tool for providing high-resolution imaging with a low radiation dose for examination of local volumes of breast tissue

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

    Energy Technology Data Exchange (ETDEWEB)

    Chon, Kwon Su [Catholic University of Daegu, Daegu (Korea, Republic of); Park, Jeong Gon; Son, Hyun Hwa; Kang, Sung Hoon; Park, Seong Hoon; Kim, Hye Won; Kim, Hun Soo; Yoon, Kwon Ha [Wonkwang University, Iksan (Korea, Republic of)

    2009-12-15

    To evaluate the efficacy for spatial resolution and radiation dose of a small-field digital mammographic imaging system using parabolic polycapillary optics. We developed a small-field digital mammographic imaging system composed of a CCD (charge coupled device) detector and an Xray source coupled with parabolic polycapillary optics. The spatial resolution and radiation dose according to various filters were evaluated for a small-field digital mammographic imaging system. The images of a test standard phantom and breast cancer tissue sample were obtained. The small-field digital mammographic imaging system had spatial resolutions of 12 lp/mm with molybdenum and rhodium filters with a 25-{mu}m thickness. With a thicker molybdenum filter (100 {mu}m thick), the system had a higher spatial resolution of 11 lp/mm and contrast of 0.48. The radiation dose for a rhodium filter with a 25-{mu}m thickness was 0.13 mGy within a 10-mm-diameter local field. A larger field image greater than 10 mm in diameter could be obtained by scanning an object. On the small-field mammographic imaging system, microcalcifications of breast cancer tissue were clearly observed. A small-field digital mammographic imaging system with parabolic polycapillary optics may be a useful diagnostic tool for providing high-resolution imaging with a low radiation dose for examination of local volumes of breast tissue.

  19. Digital mammographic tumor classification using transfer learning from deep convolutional neural networks.

    Science.gov (United States)

    Huynh, Benjamin Q; Li, Hui; Giger, Maryellen L

    2016-07-01

    Convolutional neural networks (CNNs) show potential for computer-aided diagnosis (CADx) by learning features directly from the image data instead of using analytically extracted features. However, CNNs are difficult to train from scratch for medical images due to small sample sizes and variations in tumor presentations. Instead, transfer learning can be used to extract tumor information from medical images via CNNs originally pretrained for nonmedical tasks, alleviating the need for large datasets. Our database includes 219 breast lesions (607 full-field digital mammographic images). We compared support vector machine classifiers based on the CNN-extracted image features and our prior computer-extracted tumor features in the task of distinguishing between benign and malignant breast lesions. Five-fold cross validation (by lesion) was conducted with the area under the receiver operating characteristic (ROC) curve as the performance metric. Results show that classifiers based on CNN-extracted features (with transfer learning) perform comparably to those using analytically extracted features [area under the ROC curve [Formula: see text

  20. Evaluation Of Digital Unsharp-Mask Filtering For The Detection Of Subtle Mammographic Microcalcifications

    Science.gov (United States)

    Chan, Heang-Ping; Vyborny, Carl J.; MacMahon, Heber; Metz, Charles E.; Doi, Kunio; Sickles, Edward A.

    1986-06-01

    We have conducted a study to assess the effects of digitization and unsharp-mask filtering on the ability of observers to detect subtle microcalcifications in mammograms. Thirty-two conventional screen-film mammograms were selected from patient files by two experienced mammographers. Twelve of the mammograms contained a suspicious cluster of microcalcifications in patients who subsequently underwent biopsy. Twenty of the mammograms were normal cases which were initially interpreted as being free of clustered microcalcifications and did not demonstrate such on careful review. The mammograms were digitized with a high-quality Fuji image processing/simulation system. The system consists of two drum scanners with which an original radiograph can be digitized, processed by a minicomputer, and reconstituted on film. In this study, we employed a sampling aperture of 0.1 mm X 0.1 mm and a sampling distance of 0.1 mm. The density range from 0.2 to 2.75 was digitized to 1024 grey levels per pixel. The digitized images were printed on a single emulsion film with a display aperture having the same size as the sampling aperture. The system was carefully calibrated so that the density and contrast of a digitized image were closely matched to those of the original radiograph. Initially, we evaluated the effects of the weighting factor and the mask size of a unsharp-mask filter on the appearance of mammograms for various types of breasts. Subjective visual comparisons suggested that a mask size of 91 X 91 pixels (9.1 mm X 9.1 mm) enhances the visibility of microcalcifications without excessively increasing the high-frequency noise. Further, a density-dependent weighting factor that increases linearly from 1.5 to 3.0 in the density range of 0.2 to 2.5 enhances the contrast of microcalcifications without introducing many potentially confusing artifacts in the low-density areas. An unsharp-mask filter with these parameters was used to process the digitized mammograms. We conducted

  1. Monte Carlo simulation of a mammographic test phantom

    International Nuclear Information System (INIS)

    Hunt, R. A.; Dance, D. R.; Pachoud, M.; Carlsson, G. A.; Sandborg, M.; Ullman, G.

    2005-01-01

    A test phantom, including a wide range of mammographic tissue equivalent materials and test details, was imaged on a digital mammographic system. In order to quantify the effect of scatter on the contrast obtained for the test details, calculations of the scatter-to-primary ratio (S/P) have been made using a Monte Carlo simulation of the digital mammographic imaging chain, grid and test phantom. The results show that the S/P values corresponding to the imaging conditions used were in the range 0.084-0.126. Calculated and measured pixel values in different regions of the image were compared as a validation of the model and showed excellent agreement. The results indicate the potential of Monte Carlo methods in the image quality-patient dose process optimisation, especially in the assessment of imaging conditions not available on standard mammographic units. (authors)

  2. Uncertainties of exposure-related quantities in mammographic x-ray unit quality control

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Pattison, John E.; Bibbo, Giovanni

    2006-01-01

    Breast screening programs operate in many countries with mammographic x-ray units subject to stringent quality control tests. These tests include the evaluation of quantities based on exposure measurements, such as half value layer, automatic exposure control reproducibility, average glandular dose, and radiation output rate. There are numerous error sources that contribute to the uncertainty of these exposure-related quantities, some of which are unique to the low energy x-ray spectrum produced by mammographic x-ray units. For each of these exposure-related quantities, the applicable error sources and their magnitudes vary, depending on the test equipment used to make the measurement, and whether or not relevant corrections have been applied. This study has identified and quantified a range of error sources that may be used to estimate the combined uncertainty of these exposure-related quantities, given the test equipment used and corrections applied. The uncertainty analysis uses methods described by the International Standards Organization's Guide to the Expression of Uncertainty in Measurement. Examples of how these error sources combine to give the uncertainty of the exposure-related quantities are presented. Using the best test equipment evaluated in this study, uncertainties of the four exposure-related quantities at the 95% confidence interval were found to be ±1.6% (half value layer), ±0.0008 (automatic exposure control reproducibility), ±2.3% (average glandular dose), and ±2.1% (radiation output rate). In some cases, using less precise test equipment or failing to apply corrections, resulted in uncertainties more than double in magnitude

  3. Mammographic x-ray unit kilovoltage test tool based on k-edge absorption effect.

    Science.gov (United States)

    Napolitano, Mary E; Trueblood, Jon H; Hertel, Nolan E; David, George

    2002-09-01

    A simple tool to determine the peak kilovoltage (kVp) of a mammographic x-ray unit has been designed. Tool design is based on comparing the effect of k-edge discontinuity of the attenuation coefficient for a series of element filters. Compatibility with the mammography accreditation phantom (MAP) to obtain a single quality control film is a second design objective. When the attenuation of a series of sequential elements is studied simultaneously, differences in the absorption characteristics due to the k-edge discontinuities are more evident. Specifically, when the incident photon energy is higher than the k-edge energy of a number of the elements and lower than the remainder, an inflection may be seen in the resulting attenuation data. The maximum energy of the incident photon spectra may be determined based on this inflection point for a series of element filters. Monte Carlo photon transport analysis was used to estimate the photon transmission probabilities for each of the sequential k-edge filter elements. The photon transmission corresponds directly to optical density recorded on mammographic x-ray film. To observe the inflection, the element filters chosen must have k-edge energies that span a range greater than the expected range of the end point energies to be determined. For the design, incident x-ray spectra ranging from 25 to 40 kVp were assumed to be from a molybdenum target. Over this range, the k-edge energy changes by approximately 1.5 keV between sequential elements. For this design 21 elements spanning an energy range from 20 to 50 keV were chosen. Optimum filter element thicknesses were calculated to maximize attenuation differences at the k-edge while maintaining optical densities between 0.10 and 3.00. Calculated relative transmission data show that the kVp could be determined to within +/-1 kV. To obtain experimental data, a phantom was constructed containing 21 different elements placed in an acrylic holder. MAP images were used to determine

  4. Mammographic x-ray unit kilovoltage test tool based on k-edge absorption effect

    International Nuclear Information System (INIS)

    Napolitano, Mary E.; Trueblood, Jon H.; Hertel, Nolan E.; David, George

    2002-01-01

    A simple tool to determine the peak kilovoltage (kVp) of a mammographic x-ray unit has been designed. Tool design is based on comparing the effect of k-edge discontinuity of the attenuation coefficient for a series of element filters. Compatibility with the mammography accreditation phantom (MAP) to obtain a single quality control film is a second design objective. When the attenuation of a series of sequential elements is studied simultaneously, differences in the absorption characteristics due to the k-edge discontinuities are more evident. Specifically, when the incident photon energy is higher than the k-edge energy of a number of the elements and lower than the remainder, an inflection may be seen in the resulting attenuation data. The maximum energy of the incident photon spectra may be determined based on this inflection point for a series of element filters. Monte Carlo photon transport analysis was used to estimate the photon transmission probabilities for each of the sequential k-edge filter elements. The photon transmission corresponds directly to optical density recorded on mammographic x-ray film. To observe the inflection, the element filters chosen must have k-edge energies that span a range greater than the expected range of the end point energies to be determined. For the design, incident x-ray spectra ranging from 25 to 40 kVp were assumed to be from a molybdenum target. Over this range, the k-edge energy changes by approximately 1.5 keV between sequential elements. For this design 21 elements spanning an energy range from 20 to 50 keV were chosen. Optimum filter element thicknesses were calculated to maximize attenuation differences at the k-edge while maintaining optical densities between 0.10 and 3.00. Calculated relative transmission data show that the kVp could be determined to within ±1 kV. To obtain experimental data, a phantom was constructed containing 21 different elements placed in an acrylic holder. MAP images were used to determine

  5. Task-Specific Optimization of Mammographic Systems

    National Research Council Canada - National Science Library

    Saunders, Robert

    2005-01-01

    .... This model was verified by a human observer performance experiment. The next objective explored the physical properties of a digital mammographic system, including resolution, noise, efficiency, and lag...

  6. Dose surveys in two digital mammography units using DICOM headers

    International Nuclear Information System (INIS)

    Tsalafoutas, I.; Michalaki, C.; Papagiannopoulou, C.; Efstathopoulos, E.

    2012-01-01

    Background and objective: Digital mammography units store images in DICOM format. Thus, data regarding the acquisition parameters are available within DICOM headers, including among others, the anode/filter combination, tube potential and tube current exposure time product, compressed breast thickness, entrance surface air kerma (ESAK) and mean glandular dose (MGD). However, manual extraction of these data for the verification of the displayed values' accuracy and for dose survey purposes is time consuming. Our objective was to develop a method that enables the automation of such procedures. Materials and methods: Two hundred mammographic examinations (800 mammograms) performed in two digital units (GE, Essential) were recorded on CD-roms. Using appropriate software (DICOM Info Extractor) all dose related DICOM headers were extracted into a Microsoft Excel based spreadsheet, containing embedded algorithms for the calculation of ESAK and MGD according to Dance et al (Phys. Med. Biol. 45, 2000) methodology. Results: The ESAK and MGD values stored in the DICOM headers were compared with those calculated and in most cases were within ±10%. The basic difference among the two mammographic units is that, the older one calculates MGD assuming a breast composition 50% glandular-50% adipose tissue, while the newer one calculates the actual breast glandularity and stores this value in a DICOM header. The average MGD values were 1.21 mGy and 1.38 mGy, respectively. Conclusion: For the units studied, the ESAK and MGD values stored in DICOM headers are reliable. Utilizing tools for their automatic extraction provides an easy way to perform dose surveys. (authors)

  7. Digital Breast Tomosynthesis versus Supplemental Diagnostic Mammographic Views for Evaluation of Noncalcified Breast Lesions

    Science.gov (United States)

    Bandos, Andriy I.; Ganott, Marie A.; Sumkin, Jules H.; Kelly, Amy E.; Catullo, Victor J.; Rathfon, Grace Y.; Lu, Amy H.; Gur, David

    2013-01-01

    Purpose: To compare the diagnostic performance of breast tomosynthesis versus supplemental mammography views in classification of masses, distortions, and asymmetries. Materials and Methods: Eight radiologists who specialized in breast imaging retrospectively reviewed 217 consecutively accrued lesions by using protocols that were HIPAA compliant and institutional review board approved in 182 patients aged 31–60 years (mean, 50 years) who underwent diagnostic mammography and tomosynthesis. The lesions in the cohort included 33% (72 of 217) cancers and 67% (145 of 217) benign lesions. Eighty-four percent (182 of 217) of the lesions were masses, 11% (25 of 217) were asymmetries, and 5% (10 of 217) were distortions that were initially detected at clinical examination in 8% (17 of 217), at mammography in 80% (173 of 217), at ultrasonography (US) in 11% (25 of 217), or at magnetic resonance imaging in 1% (2 of 217). Histopathologic examination established truth in 191 lesions, US revealed a cyst in 12 lesions, and 14 lesions had a normal follow-up. Each lesion was interpreted once with tomosynthesis and once with supplemental mammographic views; both modes included the mediolateral oblique and craniocaudal views in a fully crossed and balanced design by using a five-category Breast Imaging Reporting and Data System (BI-RADS) assessment and a probability-of-malignancy score. Differences between modes were analyzed with a generalized linear mixed model for BI-RADS–based sensitivity and specificity and with modified Obuchowski-Rockette approach for probability-of-malignancy–based area under the receiver operating characteristic (ROC) curve. Results: Average probability-of-malignancy–based area under the ROC curve was 0.87 for tomosynthesis versus 0.83 for supplemental views (P tomosynthesis, the false-positive rate decreased from 85% (989 of 1160) to 74% (864 of 1160) (P tomosynthesis, more cancers were classified as BI-RADS category 5 (39% [226 of 576] vs 33% [188

  8. Accuracy and reading time for six strategies using digital breast tomosynthesis in women with mammographically negative dense breasts.

    Science.gov (United States)

    Tagliafico, Alberto Stefano; Calabrese, Massimo; Bignotti, Bianca; Signori, Alessio; Fisci, Erica; Rossi, Federica; Valdora, Francesca; Houssami, Nehmat

    2017-12-01

    To compare six strategies using digital breast tomosynthesis in women with mammographically negative dense breasts. This is a substudy of the 'ASTOUND' trial. 163 women who underwent tomosynthesis with synthetically reconstructed projection images (S-2D) inclusive of 13 (7.9%) cases diagnosed with breast cancer at histopathology after surgery were evaluated. Accuracy measures and screen-reading time of six reading strategies were assessed: (A) Single reading of S-2D alone, (B) single reading of tomosynthesis alone, (C) single reading of joint interpretation of tomosynthesis + S-2D, (D) double-reading of S-2D alone, (E) double reading of tomosynthesis alone, (F) double reading of joint interpretation of tomosynthesis + S-2D. The median age of the patients was 53 years (range, 36-88 years). The highest global accuracy was obtained with double reading of tomosynthesis + S2D (F) with an AUC of 0.979 (ptomosynthesis+ S2D had the best accuracy of six screen-reading strategies although it had the longest reading time. • Tomosynthesis acquisitions are progressively implemented with reconstructed synthesized 2D images • Double reading using S-2D plus tomosynthesis had the highest global accuracy (ptomosynthesis increased reading time.

  9. Mammographic microcalcifications: Detection with xerography, screen-film, and digitized film display

    International Nuclear Information System (INIS)

    Smathers, R.L.; Bush, E.; Drace, J.; Stevens, M.; Sommer, F.G.; Brown, B.W.; Karras, B.

    1986-01-01

    Pulverized bone specks and aluminum oxide specks were measured by hand into sizes ranging from 0.2 mm to 1.0 mm and then arranged in clusters. These clusters were superimposed on a human breast tissue phantom, and xeromammograms and screen-film mammograms of the clusters were made. The screen-film mammograms were digitized using a high-resolution laser scanner and then displayed on cathode ray tube (CRT) monitors. Six radiologists independently counted the microcalcifications on the xeromammograms, the screen-film mammograms, and the digitized film mammograms. The xeromammograms were examined with a magnifying glass; the screen-film images were examined with a magnifying glass and by hot light; and the digitized-film images were examined by electronic magnification and image processing. The bone speck size that corresponded to a mean 50% detectability level for each technique was as follows: xeromammography, 0.550 mm; digitized film, 0.573 mm; and screen-film, 0.661 mm. We postulate that electronic magnification and image processing with edge enhancement can improve the capability of screen-film mammography to enhance the detection of microcalcifications

  10. Breast imaging using an amorphous silicon-based full-field digital mammographic system: stability of a clinical prototype.

    Science.gov (United States)

    Vedantham, S; Karellas, A; Suryanarayanan, S; D'Orsi, C J; Hendrick, R E

    2000-11-01

    An amorphous silicon-based full-breast imager for digital mammography was evaluated for detector stability over a period of 1 year. This imager uses a structured CsI:TI scintillator coupled to an amorphous silicon layer with a 100-micron pixel pitch and read out by special purpose electronics. The stability of the system was characterized using the following quantifiable metrics: conversion factor (mean number of electrons generated per incident x-ray), presampling modulation transfer function (MTF), detector linearity and sensitivity, detector signal-to-noise ratio (SNR), and American College of Radiology (ACR) accreditation phantom scores. Qualitative metrics such as flat field uniformity, geometric distortion, and Society of Motion Picture and Television Engineers (SMPTE) test pattern image quality were also used to study the stability of the system. Observations made over this 1-year period indicated that the maximum variation from the average of the measurements were less than 0.5% for conversion factor, 3% for presampling MTF over all spatial frequencies, 5% for signal response, linearity and sensitivity, 12% for SNR over seven locations for all 3 target-filter combinations, and 0% for ACR accreditation phantom scores. ACR mammographic accreditation phantom images indicated the ability to resolve 5 fibers, 4 speck groups, and 5 masses at a mean glandular dose of 1.23 mGy. The SMPTE pattern image quality test for the display monitors used for image viewing indicated ability to discern all contrast steps and ability to distinguish line-pair images at the center and corners of the image. No bleeding effects were observed in the image. Flat field uniformity for all 3 target-filter combinations displayed no artifacts such as gridlines, bad detector rows or columns, horizontal or vertical streaks, or bad pixels. Wire mesh screen images indicated uniform resolution and no geometric distortion.

  11. Mammographic interpretation

    International Nuclear Information System (INIS)

    Tabor, L.

    1987-01-01

    For mammography to be an effective diagnostic method, it must be performed to a very high standard of quality. Otherwise many lesions, in particular cancer in its early stages, will simply not be detectable on the films, regardless of the skill of the mammographer. Mammographic interpretation consists of two basic steps: perception and analysis. The process of mammographic interpretation begins with perception of the lesion on the mammogram. Perception is influenced by several factors. One of the most important is the parenchymal pattern of the breast tissue, detection of pathologic lesions being easier with fatty involution. The mammographer should use a method for the systematic viewing of the mammograms that will ensure that all parts of each mammogram are carefully searched for the presence of lesions. The method of analysis proceeds according to the type of lesion. The contour analysis of primary importance in the evaluation of circumscribed tumors. After having analyzed the contour and density of a lesion and considered its size, the mammographer should be fairly certain whether the circumscribed tumor is benign or malignant. Fine-needle puncture and/or US may assist the mammographer in making this decision. Painstaking analysis is required because many circumscribed tumors do not need to be biopsied. The perception of circumscribed tumors seldom causes problems, but their analysis needs careful attention. On the other hand, the major challenge with star-shaped lesions is perception. They may be difficult to discover when small. Although the final diagnosis of a stellate lesion can be made only with the help of histologic examination, the preoperative mammorgraphic differential diagnosis can be highly accurate. The differential diagnostic problem is between malignant tumors (scirrhous carcinoma), on the one hand, and traumatic fat necrosis as well as radial scars on the other hand

  12. Modeling indirect detectors for performance optimization of a digital mammographic detector for dual energy applications

    International Nuclear Information System (INIS)

    Martini, N; Koukou, V; Sotiropoulou, P; Nikiforidis, G; Kalyvas, N; Michail, C; Valais, I; Kandarakis, I; Fountos, G; Bakas, A

    2015-01-01

    Dual Energy imaging is a promising method for visualizing masses and microcalcifications in digital mammography. The advent of two X-ray energies (low and high) requires a suitable detector. The scope of this work is to determine optimum detector parameters for dual energy applications. The detector was modeled through the linear cascaded (LCS) theory. It was assumed that a phosphor material was coupled to a CMOS photodetector (indirect detection). The pixel size was 22.5 μm. The phosphor thickness was allowed to vary between 20mg/cm 2 and 160mg/cm 2 The phosphor materials examined where Gd 2 O 2 S:Tb and Gd 2 O 2 S:Eu. Two Tungsten (W) anode X-ray spectra at 35 kV (filtered with 100 μm Palladium (Pd)) and 70 kV (filtered with 800 pm Ytterbium (Yb)), corresponding to low and high energy respectively, were considered to be incident on the detector. For each combination the contrast- to-noise ratio (CNR) and the detector optical gain (DOG), showing the sensitivity of the detector, were calculated. The 40 mg/cm 2 and 70 mg/cm 2 Gd 2 O 2 S:Tb exhibited the higher DOG values for the low and high energy correspondingly. Higher CNR between microcalcification and mammary gland exhibited the 70mg/cm 2 and the 100mg/cm 2 Gd 2 O 2 S:Tb for the low and the high energy correspondingly

  13. Mammography and mammographic screening in the United Kingdom: Practices, regulations and radiation dosimetry

    International Nuclear Information System (INIS)

    Fitzgerald, M.

    1987-01-01

    The radiation-induced cancers due to mammography represent about 0.6 % of the natural incidence in this survey and would seem to be a very small risk. If the frequency or period of screening was increased, the risk would be enhanced. However, it should be possible to reduce the radiation dose to less than the mean value used here. For example, if film screen mammography alone was used for this population, the quoted risk would be reduced by 25%. The dose is also reduced by the use of a single view. The relatively low risk to the breast is a consequence partly of the low dose mammographic techniques that can now be practised, and partly of the acceptance of mean breast dose, which may be an order to magnitude less than the surface dose, as the measure of risk. The risk to other organs should be negligible provided that the X-ray field is carefully collimated and that the breast table incorporates a primary absorber

  14. Pilot study of intraoperative digital imaging with the use of a mammograph for assessment of bone surgical margins in the head and neck region

    International Nuclear Information System (INIS)

    Ntomouchtsis, A.; Xinou, K.; Patrikidou, A.; Paraskevopoulos, K.; Kechagias, N.; Tsekos, A.; Balis, G.C.; Gerasimidou, D.; Thuau, H.; Mangoudi, D.; Vahtsevanos, K.

    2013-01-01

    Aim: To investigate alternative possibilities for the intraoperative evaluation of surgical margins after bone resection utilizing more conventional hospital infrastructure technologies. Materials and methods: A small pilot study was performed using digital mammograph imaging intraoperatively on 16 surgical specimens of bone tumours or malignancies with bone infiltration of the head and neck area, with the aim of evaluating the resection margins. Results: In thirteen cases the intraoperative specimen images indicated clinically complete excision. In two cases incomplete resection or close proximity of margins was detected, which required additional resection. Conclusions: The results indicated that intraoperative specimen radiography can prove useful in evaluating completeness of excision. The significance of intraoperative assessment of surgical margin is of paramount importance when immediate reconstruction is performed. This proposed method is cheap, easy to perform and fast. Its cost–benefit ratio is superior than that of any other available technique. Intraoperative analysis of specimens with digital mammography imaging can potentially become a useful tool for immediate evaluation of osseous margins after resection

  15. Evaluation of the image quality in digital breast tomosynthesis (DBT) employed with a compressed-sensing (CS)-based reconstruction algorithm by using the mammographic accreditation phantom

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yeonok; Cho, Heemoon; Je, Uikyu; Cho, Hyosung, E-mail: hscho1@yonsei.ac.kr; Park, Chulkyu; Lim, Hyunwoo; Kim, Kyuseok; Kim, Guna; Park, Soyoung; Woo, Taeho; Choi, Sungil

    2015-12-21

    In this work, we have developed a prototype digital breast tomosynthesis (DBT) system which mainly consists of an x-ray generator (28 kV{sub p}, 7 mA s), a CMOS-type flat-panel detector (70-μm pixel size, 230.5×339 mm{sup 2} active area), and a rotational arm to move the x-ray generator in an arc. We employed a compressed-sensing (CS)-based reconstruction algorithm, rather than a common filtered-backprojection (FBP) one, for more accurate DBT reconstruction. Here the CS is a state-of-the-art mathematical theory for solving the inverse problems, which exploits the sparsity of the image with substantially high accuracy. We evaluated the reconstruction quality in terms of the detectability, the contrast-to-noise ratio (CNR), and the slice-sensitive profile (SSP) by using the mammographic accreditation phantom (Model 015, CIRS Inc.) and compared it to the FBP-based quality. The CS-based algorithm yielded much better image quality, preserving superior image homogeneity, edge sharpening, and cross-plane resolution, compared to the FBP-based one. - Highlights: • A prototype digital breast tomosynthesis (DBT) system is developed. • Compressed-sensing (CS) based reconstruction framework is employed. • We reconstructed high-quality DBT images by using the proposed reconstruction framework.

  16. Portable Power And Digital-Communication Units

    Science.gov (United States)

    Levin, Richard R.; Henry, Paul K.; Rosenberg, Leigh S.

    1992-01-01

    Conceptual network of electronic-equipment modules provides electrical power and digital radio communications at multiple sites not served by cables. System includes central communication unit and portable units powered by solar photovoltaic arrays. Useful to serve equipment that must be set up quickly at remote sites or buildings that cannot be modified to provide cable connections.

  17. Volumetric breast density affects performance of digital screening mammography

    OpenAIRE

    Wanders, JO; Holland, K; Veldhuis, WB; Mann, RM; Pijnappel, RM; Peeters, PH; Van Gils, CH; Karssemeijer, N

    2016-01-01

    PURPOSE: To determine to what extent automatically measured volumetric mammographic density influences screening performance when using digital mammography (DM). METHODS: We collected a consecutive series of 111,898 DM examinations (2003-2011) from one screening unit of the Dutch biennial screening program (age 50-75 years). Volumetric mammographic density was automatically assessed using Volpara. We determined screening performance measures for four density categories comparable to the Ameri...

  18. Diagnostic implications of asymmetrical mammographic patterns

    International Nuclear Information System (INIS)

    Asenjo, M.; Ania, B.J.

    1997-01-01

    To analyze the effect of asymmetrical mammographic patterns of the diagnosis of breast cancer. In a series of 6, 476 patients referred to a Breast Imaging Diagnosis Unit, we excluded males, women with previous breast surgery, and cases in which mammography was not performed, which left 5,203 women included. Each breast was classified according to one of four patterns of mammographic parenchymal density. Asymmetry was considered to exist when a patient's breasts had different patterns. Breast cancer was confirmed histologically in 282 (5.4%) women. The mammographic pattern was asymmetrical in 8% of the women with cancer and in 2% of the women without cancer (p<0.001). Fine-needle aspiration biopsy was performed in 78% and 96% (p=0.04), respectively, of the women with and without mammographic asymmetry who had neoplasms, and in 33% and 22% (p=0.02), respectively, of the women with and without mammographic asymmetry who did not have neoplasms. Asymmetrical mammographic pattern was four times more frequent in the women with breast cancer. This asymmetry decreased the frequency of needle biopsy in women with cancer, but increased the frequency of needle biopsy in women without cancer. (Author) 11 refs

  19. Mammographic image enhancement using wavelet transform and homomorphic filter

    Directory of Open Access Journals (Sweden)

    F Majidi

    2015-12-01

    Full Text Available Mammography is the most effective method for the early diagnosis of breast cancer diseases. As mammographic images contain low signal to noise ratio and low contrast, it becomes too difficult for radiologists to analyze mammogram. To deal with the above stated problems, it is very important to enhance the mammographic images using image processing methods. This paper introduces a new image enhancement approach for mammographic images which uses the modified mathematical morphology, wavelet transform and homomorphic filter to suppress the noise of images. For performance evaluation of the proposed method, contrast improvement index (CII and edge preservation index (EPI are adopted. Experimental results on mammographic images from Pejvak Digital Imaging Center (PDIC show that the proposed algorithm improves the two indexes, thereby achieving the goal of enhancing mammographic images.

  20. Digital tape unit test facility software

    Science.gov (United States)

    Jackson, J. T.

    1971-01-01

    Two computer programs are described which are used for the collection and analysis of data from the digital tape unit test facility (DTUTF). The data are the recorded results of skew tests made on magnetic digital tapes which are used on computers as input/output media. The results of each tape test are keypunched onto an 80 column computer card. The format of the card is checked and the card image is stored on a master summary tape via the DTUTF card checking and tape updating system. The master summary tape containing the results of all the tape tests is then used for analysis as input to the DTUTF histogram generating system which produces a histogram of skew vs. date for selected data, followed by some statistical analysis of the data.

  1. Mammographic screening programmes in Europe

    DEFF Research Database (Denmark)

    Giordano, Livia; von Karsa, Lawrence; Tomatis, Mariano

    2012-01-01

    To summarize participation and coverage rates in population mammographic screening programmes for breast cancer in Europe.......To summarize participation and coverage rates in population mammographic screening programmes for breast cancer in Europe....

  2. Digital preservation initiatives in the United States: a summary

    OpenAIRE

    Marcum, Deanna

    2003-01-01

    General presentation on how digital preservation issues are being faced in the United States of America. Special reference to the National Digital Information Infrastructure and Preservation Program, that is found at the Library of Congress, and aims to implement a national strategy for the long-term preservation of digital content.

  3. Should processed or raw image data be used in mammographic image quality analyses? A comparative study of three full-field digital mammography systems

    International Nuclear Information System (INIS)

    Borg, Mark; Badr, Ishmail; Royle, Gary

    2015-01-01

    The purpose of this study is to compare a number of measured image quality parameters using processed and unprocessed or raw images in two full-field direct digital units and one computed radiography mammography system. This study shows that the difference between raw and processed image data is system specific. The results have shown that there are no significant differences between raw and processed data in the mean threshold contrast values using the contrast-detail mammography phantom in all the systems investigated; however, these results cannot be generalised to all available systems. Notable differences were noted in contrast-to-noise ratios and in other tests including: response function, modulation transfer function, noise equivalent quanta, normalised noise power spectra and detective quantum efficiency as specified in IEC 62220-1-2. Consequently, the authors strongly recommend the use of raw data for all image quality analyses in digital mammography. (authors)

  4. The digital ultrasonic test unit for automatic equipment

    International Nuclear Information System (INIS)

    Hiraoka, T.; Matsuyama, H.

    1976-01-01

    The operations and features of the ultrasonic test unit used and the digital data processing techniques employed are described. This unit is used for a few hundred multi-channel automatic ultrasonic test equipment

  5. Proton Testing of Advanced Stellar Compass Digital Processing Unit

    DEFF Research Database (Denmark)

    Thuesen, Gøsta; Denver, Troelz; Jørgensen, Finn E

    1999-01-01

    The Advanced Stellar Compass Digital Processing Unit was radiation tested with 300 MeV protons at Proton Irradiation Facility (PIF), Paul Scherrer Institute, Switzerland.......The Advanced Stellar Compass Digital Processing Unit was radiation tested with 300 MeV protons at Proton Irradiation Facility (PIF), Paul Scherrer Institute, Switzerland....

  6. Mammographic density and breast cancer risk in breast screening assessment cases and women with a family history of breast cancer.

    Science.gov (United States)

    Duffy, Stephen W; Morrish, Oliver W E; Allgood, Prue C; Black, Richard; Gillan, Maureen G C; Willsher, Paula; Cooke, Julie; Duncan, Karen A; Michell, Michael J; Dobson, Hilary M; Maroni, Roberta; Lim, Yit Y; Purushothaman, Hema N; Suaris, Tamara; Astley, Susan M; Young, Kenneth C; Tucker, Lorraine; Gilbert, Fiona J

    2018-01-01

    Mammographic density has been shown to be a strong independent predictor of breast cancer and a causative factor in reducing the sensitivity of mammography. There remain questions as to the use of mammographic density information in the context of screening and risk management, and of the association with cancer in populations known to be at increased risk of breast cancer. To assess the association of breast density with presence of cancer by measuring mammographic density visually as a percentage, and with two automated volumetric methods, Quantra™ and VolparaDensity™. The TOMosynthesis with digital MammographY (TOMMY) study of digital breast tomosynthesis in the Breast Screening Programme of the National Health Service (NHS) of the United Kingdom (UK) included 6020 breast screening assessment cases (of whom 1158 had breast cancer) and 1040 screened women with a family history of breast cancer (of whom two had breast cancer). We assessed the association of each measure with breast cancer risk in these populations at enhanced risk, using logistic regression adjusted for age and total breast volume as a surrogate for body mass index (BMI). All density measures showed a positive association with presence of cancer and all declined with age. The strongest effect was seen with Volpara absolute density, with a significant 3% (95% CI 1-5%) increase in risk per 10 cm 3 of dense tissue. The effect of Volpara volumetric density on risk was stronger for large and grade 3 tumours. Automated absolute breast density is a predictor of breast cancer risk in populations at enhanced risk due to either positive mammographic findings or family history. In the screening context, density could be a trigger for more intensive imaging. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Digital management of an electron microscope unit

    International Nuclear Information System (INIS)

    Elea, N.; Dickson, M.; Munroe, P.

    2002-01-01

    Full text: Electron microscope units, especially those such as ours, which operate as a central infrastructural facility are increasingly asked to provide more service, over more instruments with decreasing, or limited, financial resources. We believe that staff time is best used performing electron microscopy, assisting users and maintaining instrumentation rather than in the pursuit of red tape. One solution to this problem has been the creation of a control system which performs all routine acts of data management, such as the archiving and accessing of digital data, providing access to bookings, and most importantly in the era of user pays services, logging time and billing users. The system we have created, developed and expanded allows the users themselves to access our server through any web-browser and make their own bookings or access and manipulate their data. Users themselves must log on to a microscope through swipecard readers before it can be used and log-off after use. Their time is logged precisely and an exquisitely fair user pays systems can be operated by transferring logged usage time to spreadsheets to calculate charges. Furthermore, this system acts as a method of user authentication and can be used to bar incompetent or unauthorised users. The system has recently been upgraded to increase its utility to include sensors that monitor the electron microscope operating environment, such as magnetic field, room temperature, water flow etc, so that if these parameters depart significantly from optimum levels electron microscope unit staff may be alerted. In this presentation the structure of our system will be described and the advantages and disadvantages of such a system will be discussed. Copyright (2002) Australian Society for Electron Microscopy Inc

  8. The Mammographic Head Demonstrator Developed in the Framework of the “IMI” Project:. First Imaging Tests Results

    Science.gov (United States)

    Bisogni, Maria Giuseppina

    2006-04-01

    In this paper we report on the performances and the first imaging test results of a digital mammographic demonstrator based on GaAs pixel detectors. The heart of this prototype is the X-ray detection unit, which is a GaAs pixel sensor read-out by the PCC/MEDIPIXI circuit. Since the active area of the sensor is 1 cm2, 18 detectors have been organized in two staggered rows of nine chips each. To cover the typical mammographic format (18 × 24 cm2) a linear scanning is performed by means of a stepper motor. The system is integrated in mammographic equipment comprehending the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies in collaboration with the universities of Ferrara, Roma “La Sapienza”, Pisa and the INFN.

  9. Digital control for turbogas units; Control digital para unidades turbogas

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Beltran, Carlos Daniel

    1997-02-01

    The present thesis deals with the rehabilitation of the control system for the gas turbines W501 of the Gomez Palacio Combined Cycle Power Station in the state of Durango, Mexico. The first part of the development deals with a re-engineering process of software applied to the digital control system of the gas turbines of the Gomez Palacio Combined Cycle Power Station. This process was developed using concepts of several branches of engineering: a) involved the knowledge of the software engineering, using formal methods for the analysis of the original system and the redesign of the new system; b) The control engineering was used in the analysis of diverse control and automation strategies employed for gas turbines control, with the objective of verifying the type of instructions and existing routines within the software. The final product of this stage is a modulated programmatic system, based on structured design that is functionally a mirror image of the original system. The system obtained conformed by five main modules which are based on a model proposed originally for control by batch: i) Man Machine Interface, ii) Regulatory Control, iii) Protections, iv) Logic sequences and v) Supervision. The second stage of development was the improvement of the speed control of the turbine. When a turbogas unit is controlled, it must be taken into account several operation stages such as the starting, the control in stable state and the shut down. The real behavior of the turbine during the starting, and mainly the great number of backward movements produced, proposed by itself the search of a new controller who more closely maintained the acceleration specifications whereupon the turbine was designed. The development of a new control algorithm began with the analysis of the process, trying to identify which are the critical stages of this one and be able to evaluate in an objective form the advantages of an algorithm upon the other. It was continued with the

  10. Neural network recognition of mammographic lesions

    International Nuclear Information System (INIS)

    Oldham, W.J.B.; Downes, P.T.; Hunter, V.

    1987-01-01

    A method for recognition of mammographic lesions through the use of neural networks is presented. Neural networks have exhibited the ability to learn the shape andinternal structure of patterns. Digitized mammograms containing circumscribed and stelate lesions were used to train a feedfoward synchronous neural network that self-organizes to stable attractor states. Encoding of data for submission to the network was accomplished by performing a fractal analysis of the digitized image. This results in scale invariant representation of the lesions. Results are discussed

  11. Enhancement and denoising of mammographic images for breast disease detection

    International Nuclear Information System (INIS)

    Yazdani, S.; Yusof, R.; Karimian, A.; Hematian, A.; Yousefi, M.

    2012-01-01

    In these two decades breast cancer is one of the leading cause of death among women. In breast cancer research, Mammographic Image is being assessed as a potential tool for detecting breast disease and investigating response to chemotherapy. In first stage of breast disease discovery, the density measurement of the breast in mammographic images provides very useful information. Because of the importance of the role of mammographic images the need for accurate and robust automated image enhancement techniques is becoming clear. Mammographic images have some disadvantages such as, the high dependence of contrast upon the way the image is acquired, weak distinction in splitting cyst from tumor, intensity non uniformity, the existence of noise, etc. These limitations make problem to detect the typical signs such as masses and microcalcifications. For this reason, denoising and enhancing the quality of mammographic images is very important. The method which is used in this paper is in spatial domain which its input includes high, intermediate and even very low contrast mammographic images based on specialist physician's view, while its output is processed images that show the input images with higher quality, more contrast and more details. In this research, 38 mammographic images have been used. The result of purposed method shows details of abnormal zones and the areas with defects so that specialist could explore these zones more accurately and it could be deemed as an index for cancer diagnosis. In this study, mammographic images are initially converted into digital images and then to increase spatial resolution power, their noise is reduced and consequently their contrast is improved. The results demonstrate effectiveness and efficiency of the proposed methods. (authors)

  12. Mammographic compression in Asian women.

    Science.gov (United States)

    Lau, Susie; Abdul Aziz, Yang Faridah; Ng, Kwan Hoong

    2017-01-01

    To investigate: (1) the variability of mammographic compression parameters amongst Asian women; and (2) the effects of reducing compression force on image quality and mean glandular dose (MGD) in Asian women based on phantom study. We retrospectively collected 15818 raw digital mammograms from 3772 Asian women aged 35-80 years who underwent screening or diagnostic mammography between Jan 2012 and Dec 2014 at our center. The mammograms were processed using a volumetric breast density (VBD) measurement software (Volpara) to assess compression force, compression pressure, compressed breast thickness (CBT), breast volume, VBD and MGD against breast contact area. The effects of reducing compression force on image quality and MGD were also evaluated based on measurement obtained from 105 Asian women, as well as using the RMI156 Mammographic Accreditation Phantom and polymethyl methacrylate (PMMA) slabs. Compression force, compression pressure, CBT, breast volume, VBD and MGD correlated significantly with breast contact area (pAsian women. The median compression force should be about 8.1 daN compared to the current 12.0 daN. Decreasing compression force from 12.0 daN to 9.0 daN increased CBT by 3.3±1.4 mm, MGD by 6.2-11.0%, and caused no significant effects on image quality (p>0.05). Force-standardized protocol led to widely variable compression parameters in Asian women. Based on phantom study, it is feasible to reduce compression force up to 32.5% with minimal effects on image quality and MGD.

  13. 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)

  14. Analytical optimization of digital subtraction mammography with contrast medium using a commercial unit.

    Science.gov (United States)

    Rosado-Méndez, I; Palma, B A; Brandan, M E

    2008-12-01

    Contrast-medium-enhanced digital mammography (CEDM) is an image subtraction technique which might help unmasking lesions embedded in very dense breasts. Previous works have stated the feasibility of CEDM and the imperative need of radiological optimization. This work presents an extension of a former analytical formalism to predict contrast-to-noise ratio (CNR) in subtracted mammograms. The goal is to optimize radiological parameters available in a clinical mammographic unit (x-ray tube anode/filter combination, voltage, and loading) by maximizing CNR and minimizing total mean glandular dose (D(gT)), simulating the experimental application of an iodine-based contrast medium and the image subtraction under dual-energy nontemporal, and single- or dual-energy temporal modalities. Total breast-entrance air kerma is limited to a fixed 8.76 mGy (1 R, similar to screening studies). Mathematical expressions obtained from the formalism are evaluated using computed mammographic x-ray spectra attenuated by an adipose/glandular breast containing an elongated structure filled with an iodinated solution in various concentrations. A systematic study of contrast, its associated variance, and CNR for different spectral combinations is performed, concluding in the proposal of optimum x-ray spectra. The linearity between contrast in subtracted images and iodine mass thickness is proven, including the determination of iodine visualization limits based on Rose's detection criterion. Finally, total breast-entrance air kerma is distributed between both images in various proportions in order to maximize the figure of merit CNR2/D(gT). Predicted results indicate the advantage of temporal subtraction (either single- or dual-energy modalities) with optimum parameters corresponding to high-voltage, strongly hardened Rh/Rh spectra. For temporal techniques, CNR was found to depend mostly on the energy of the iodinated image, and thus reduction in D(gT) could be achieved if the spectral energy

  15. 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

  16. Effective dose from direct and indirect digital panoramic units

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gun Sun; Kim, Jin Soo; Seo, Yo Seob; Kim, Jae Duk [School of Dentistry, Oral Biology Research Institute, Chosun University, Gwangju (Korea, Republic of)

    2013-06-15

    This study aimed to provide comparative measurements of the effective dose from direct and indirect digital panoramic units according to phantoms and exposure parameters. Dose measurements were carried out using a head phantom representing an average man (175 cm tall, 73.5 kg male) and a limbless whole body phantom representing an average woman (155 cm tall, 50 kg female). Lithium fluoride thermoluminescent dosimeter (TLD) chips were used for the dosimeter. Two direct and 2 indirect digital panoramic units were evaluated in this study. Effective doses were derived using 2007 International Commission on Radiological Protection (ICRP) recommendations. The effective doses of the 4 digital panoramic units ranged between 8.9 {mu}Sv and 37.8 {mu}Sv. By using the head phantom, the effective doses from the direct digital panoramic units (37.8 {mu}Sv, 27.6 {mu}Sv) were higher than those from the indirect units (8.9 {mu}Sv, 15.9 {mu}Sv). The same panoramic unit showed the difference in effective doses according to the gender of the phantom, numbers and locations of TLDs, and kVp. To reasonably assess the radiation risk from various dental radiographic units, the effective doses should be obtained with the same numbers and locations of TLDs, and with standard hospital exposure. After that, it is necessary to survey the effective doses from various dental radiographic units according to the gender with the corresponding phantom.

  17. MAS2-8 radar and digital control unit

    Science.gov (United States)

    Oberg, J. M.; Ulaby, F. T.

    1974-01-01

    The design of the MAS 2-8 (2 to 8 GHz microwave-active spectrometer), a ground-based sensor system, is presented. A major modification in 1974 to the MAS 2-8, that of a control subsystem to automate the data-taking operation, is the prime focus. The digital control unit automatically changes all system parameters except FM rate and records the return signal on paper tape. The overall system operation and a detailed discussion of the design and operation of the digital control unit are presented.

  18. Mammographic scar for stereotaxic biopsy

    International Nuclear Information System (INIS)

    Guzman Tattis; Hincapie U, Ana Lucia; Patino P, Jairo Hernando

    1997-01-01

    It is reported the case of 56 years old woman who underwent a stereotactic biopsy because of having a circumscribed breast nodule. The histologic diagnosis was benign. After six months, during the mammographic control, it was noticed that the nodule showed irregular contours, because of that a surgical biopsy was performed. The histopathology was reported as benign. it is considered then, that the mammographic changes observed in the mammographic control are due to scar phenomenon after stereotactic biopsy. This findings has not been reported previously

  19. Digital Dissertations in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Ann Matheson

    2000-05-01

    Full Text Available In the United Kingdom a user wishing to consult a UK thesis has traditionally had the following choices: the thesis may be consulted in the Library of the Higher Education Institution (HEI to which it was submitted; the thesis may be borrowed from the library of the HEI; a copy of the thesis may be purchased form the library of the HEI; the thesis may be borrowed through inter-library loan; or the thesis may be made available through the British Library’s British Thesis Service, which was set up in 1971. This Service currently holds more than 150,000 UK theses, which are added to at a rate of around 7,000 a year, with the participation of about a hundred Higher Education Institutions (HEIs. With the development of new technology, however, an interest developed in examining the feasibility of making theses available online to users. In the United Kingdom, the University Theses Online Group (UTOG was established as a consequence of a proposal to the Follett Implementation Group on Information Technology in 1994. The University Theses Online Group (UTOG is a working group of UK university librarians: the Group’s aims are to investigate the technical, cultural and administrative issues associated with the storage and delivery of theses in online form. The Group is made up of representatives of the British Library Document Supply Centre (BLDSC, British Thesis Service, and the university libraries of Cranfield, Edinburgh, Glasgow, Leeds, Manchester, Plymouth, Robert Gordon, University College London, Kent, University of London and Warwick.

  20. Quality assurance applied to mammographic equipments using phantoms and software for its evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Mayo, Patricia, E-mail: p.mayo@titaniast.co [Titania Servicios Tecnologicos S.L., Grupo Dominguis, Apartado 46015, Valencia (Spain); Rodenas, Francisco [Departamento de Matematica Aplicada, Universidad Politecnica de Valencia, Apartado 46022, Valencia (Spain); Manuel Campayo, Juan [Hospital Clinico Universitario de Valencia, Avda. Blasco Ibanez, Apartado 46017, Valencia (Spain); Verdu, Gumersido [Departamento de Ingenieria Quimica y Nuclear, Universidad Politecnica de Valencia, Apartado 46022, Valencia (Spain)

    2010-07-21

    The image quality assessment in radiographic equipments is a very important item for a complete quality control of the radiographic image chain. The periodic evaluation of the radiographic image quality must guarantee the constancy of this quality to carry out a suitable diagnosis. Mammographic phantom images are usually used to study the quality of images obtained by determined mammographic equipment. The digital image treatment techniques allow to carry out an automatic analysis of the phantom image. In this work we apply some techniques of digital image processing to analyze in an automatic way the image quality of mammographic phantoms, namely CIRS SP01 and RACON for different varying conditions of the mammographic equipment. The CIRS SP01 phantom is usually used in analogic mammographic equipments and the RACON phantom has been specifically developed by authors to be applied to acceptance and constancy tests of the image quality in digital radiographic equipments following recommendations of international associations. The purpose of this work consists in analyzing the image quality for both phantoms by means of an automatic software utility. This analysis allows us to study the functioning of the image chain of the mammographic system in an objective way, so an abnormal functioning of the radiographic equipment might be detected.

  1. Quality assurance applied to mammographic equipments using phantoms and software for its evaluation

    International Nuclear Information System (INIS)

    Mayo, Patricia; Rodenas, Francisco; Manuel Campayo, Juan; Verdu, Gumersido

    2010-01-01

    The image quality assessment in radiographic equipments is a very important item for a complete quality control of the radiographic image chain. The periodic evaluation of the radiographic image quality must guarantee the constancy of this quality to carry out a suitable diagnosis. Mammographic phantom images are usually used to study the quality of images obtained by determined mammographic equipment. The digital image treatment techniques allow to carry out an automatic analysis of the phantom image. In this work we apply some techniques of digital image processing to analyze in an automatic way the image quality of mammographic phantoms, namely CIRS SP01 and RACON for different varying conditions of the mammographic equipment. The CIRS SP01 phantom is usually used in analogic mammographic equipments and the RACON phantom has been specifically developed by authors to be applied to acceptance and constancy tests of the image quality in digital radiographic equipments following recommendations of international associations. The purpose of this work consists in analyzing the image quality for both phantoms by means of an automatic software utility. This analysis allows us to study the functioning of the image chain of the mammographic system in an objective way, so an abnormal functioning of the radiographic equipment might be detected.

  2. [Comparison of dignity determination of mammographic microcalcification with two systems for digital full-field mammography with different detector resolution: a retrospective clinical study].

    Science.gov (United States)

    Schulz-Wendtland, R; Hermann, K-P; Adamietz, B; Meier-Meitinger, M; Wenkel, E; Lell, M; Anders, K; Uder, M

    2011-02-01

    The aim of this retrospective clinical study was to compare the diagnostic accuracy of the novel 50 µm FFDM (full-field digital mammography) system (DR) with an established 70 µm system (DR) in the differential diagnosis between benign and malignant clusters of microcalcification (n=50) (BI-RADS™ classification 4/5) and to assess the possible incremental value of the 50 µm pixel-pitch on specificity. From March 2009 to September 2009, 50 patients underwent full-field digital mammography (FFDM) (detector resolution 70 µm) (Novation, Siemens, Erlangen, Germany). As there were suspicious signs of microcalcification classified with BI-RADS™ 4/5 after diagnosis and preoperative wire localization, control images were made with the new FFDM system (detector: resolution 50 µm) (Amulet, Fujifilm, Tokyo, Japan) with the same exposure parameters. The diagnosis was determined after the operation by five radiologists with different experience in digital mammography from randomly distributed mediolateral views (monitor reading) whose results were correlated with the final histology of all lesions. Histopathology revealed 19 benign and 31 malignant lesions in 50 patients after open biopsy. The results of the five readers showed a higher sensitivity of the new FFDM system (80.0%) in the ability to recognize malignant microcalcification in comparison to the established system (74.8%). The specificity (75.8 versus 71.6%) was slightly higher for the new system but these results were not statistically significant (pdetector: resolution 50 µm) was also slightly superior to the well-known system (detector: resolution 70 µm) (80.1% versus 76.4%). Our study has shown that the new full-field digital mammography system using the novel detector compared with the already established FFDM system with respect to the assessment of microcalcification is at least equivalent.

  3. Comparison of dignity determination of mammographic microcalcification with two systems for digital full-field mammography with different detector resolution. A retrospective clinical study

    International Nuclear Information System (INIS)

    Schulz-Wendtland, R.; Adamietz, B.; Meier-Meitinger, M.; Wenkel, E.; Lell, M.; Anders, K.; Uder, M.; Hermann, K.P.

    2011-01-01

    The aim of this retrospective clinical study was to compare the diagnostic accuracy of the novel 50 μm FFDM (full-field digital mammography) system (DR) with an established 70 μm system (DR) in the differential diagnosis between benign and malignant clusters of microcalcification (n=50) (BI-RADS trademark classification 4/5) and to assess the possible incremental value of the 50 μm pixel-pitch on specificity. From March 2009 to September 2009, 50 patients underwent full-field digital mammography (FFDM) (detector resolution 70 μm) (Novation, Siemens, Erlangen, Germany). As there were suspicious signs of microcalcification classified with BI-RADS trademark 4/5 after diagnosis and preoperative wire localization, control images were made with the new FFDM system (detector: resolution 50 μm) (Amulet, Fujifilm, Tokyo, Japan) with the same exposure parameters. The diagnosis was determined after the operation by five radiologists with different experience in digital mammography from randomly distributed mediolateral views (monitor reading) whose results were correlated with the final histology of all lesions. Histopathology revealed 19 benign and 31 malignant lesions in 50 patients after open biopsy. The results of the five readers showed a higher sensitivity of the new FFDM system (80.0%) in the ability to recognize malignant microcalcification in comparison to the established system (74.8%). The specificity (75.8 versus 71.6%) was slightly higher for the new system but hese results were not statistically significant (p [de

  4. Ethnicity, Soybean Consumption, and Mammographic Densities

    National Research Council Canada - National Science Library

    Maskarinec, Gertraud

    1997-01-01

    The purpose of this study is to determine whether mammographic density patterns differ by ethnic background and to explore the possible association of a soy rich diet with mammographic density patterns...

  5. [Follow-up of surgical biopsies in microcalcifications of the breast. Comparative analysis of patients submitted to mammography and digitalization of mammographic images].

    Science.gov (United States)

    Rulli, A; Cirocchi, R; Vento, A R; Naninato, P; Zanetti, A; Carli, L

    1997-01-01

    Improvements in the techniques of preoperative needle localization of nonpalpable breast lesions that have been detected at mammography, coupled with surgical biopsy of smaller volumes of breast tissue and the use of local anesthesia have produced a more aggressive attitude toward early biopsy of lesions that are suspected of malignancy. The authors report the follow-up in 92 cases, who underwent breast biopsy for microcalcifications with no palpable lesions. In 46 women the presence of microcalcifications was evaluated through a computerized instrument which allows digitalization of the image.

  6. Multiscale wavelet representations for mammographic feature analysis

    Science.gov (United States)

    Laine, Andrew F.; Song, Shuwu

    1992-12-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis through multiresolution representations. We show that efficient (nonredundant) representations may be identified from digital mammography and used to enhance specific mammographic features within a continuum of scale space. The multiresolution decomposition of wavelet transforms provides a natural hierarchy in which to embed an interactive paradigm for accomplishing scale space feature analysis. Choosing wavelets (or analyzing functions) that are simultaneously localized in both space and frequency, results in a powerful methodology for image analysis. Multiresolution and orientation selectivity, known biological mechanisms in primate vision, are ingrained in wavelet representations and inspire the techniques presented in this paper. Our approach includes local analysis of complete multiscale representations. Mammograms are reconstructed from wavelet coefficients, enhanced by linear, exponential and constant weight functions localized in scale space. By improving the visualization of breast pathology we can improve the changes of early detection of breast cancers (improve quality) while requiring less time to evaluate mammograms for most patients (lower costs).

  7. Digital remote viewing system for coronary care unit

    International Nuclear Information System (INIS)

    Cho, P.S.; Tillisch, J.; Huang, H.K.

    1987-01-01

    A digital remote viewing system developed for the coronary care unit at the UCLA Medical Center has been in clinical operation since March 1, 1987. The present system consists of three 512-line monitors, VAX 11/750, Gould IP8500 image processor and a broad-band communication system. The patients' images are acquired with a computed radiography system and are transmitted to the coronary care unit, which is five floors above the radiology department. This exhibit presents the architecture and the performance characteristics of the system. Also, the second-generation system, which consists of an intelligent local work station with three 1,024-line monitors and a fast digital communication network, will be introduced

  8. Malignant Lesions as Mammographically Appearing Intramammary Ganglia

    International Nuclear Information System (INIS)

    Martinez-Miraveta, P.; Pons, M. J.; Pina, L. J.; Zornoza, G.

    2004-01-01

    Intramammary ganglia are frequent mammographic findings of no pathological importance. We present two cases of malignant breast lesions whose mammographic appearance could resemble that of intramammary ganglia. Although the mammographic appearance of a lesion is similar to that of intramammary ganglia, it should be carefully studied, especially if it presents a poorly defined border or is palpable. (Author)

  9. Mammographic Breast Density in Malaysian Women with Breast Cancer

    International Nuclear Information System (INIS)

    Noriah Jamal; Humairah Samad Cheung

    2016-01-01

    The objective of this study was to examine the mammographic breast density of women with breast cancer detected on voluntary mammographic screening at two selected screening centers in Malaysia. This was a retrospective study of Full-Field Digital Mammography (FFDM) images of 150 Malaysian women with biopsy-proven breast cancer. The study population comprised 73 Malays (37.7 %), 59 Chinese (39.3 %) and 18 Indians (12.0 %). The Tabar breast density Patterns (I - V) were used to evaluate mammographic breast density. Data were analyzed using descriptive statistics. The results were compared with findings from a similar study on a group of 668 women who did not have breast cancer. The results showed that 44.7 % of the study population had dense breasts (Patterns IV and V), 14.7 % had predominantly fatty breasts (Patterns II and III) while 40.7 % had Pattern I. The proportion of study population with dense breasts decreased with age. In conclusion, the proportion of women with dense breasts decreased with age. Majority of the women with cancer (44.7 %) had dense breasts of Tabar Patterns IV and V, which has been associated with increased risk of breast cancer detected by voluntary mammographic screening. The results support the notion that increased breast density is a risk factor of breast cancer. (author)

  10. Minimization of annotation work: diagnosis of mammographic masses via active learning

    Science.gov (United States)

    Zhao, Yu; Zhang, Jingyang; Xie, Hongzhi; Zhang, Shuyang; Gu, Lixu

    2018-06-01

    The prerequisite for establishing an effective prediction system for mammographic diagnosis is the annotation of each mammographic image. The manual annotation work is time-consuming and laborious, which becomes a great hindrance for researchers. In this article, we propose a novel active learning algorithm that can adequately address this problem, leading to the minimization of the labeling costs on the premise of guaranteed performance. Our proposed method is different from the existing active learning methods designed for the general problem as it is specifically designed for mammographic images. Through its modified discriminant functions and improved sample query criteria, the proposed method can fully utilize the pairing of mammographic images and select the most valuable images from both the mediolateral and craniocaudal views. Moreover, in order to extend active learning to the ordinal regression problem, which has no precedent in existing studies, but is essential for mammographic diagnosis (mammographic diagnosis is not only a classification task, but also an ordinal regression task for predicting an ordinal variable, viz. the malignancy risk of lesions), multiple sample query criteria need to be taken into consideration simultaneously. We formulate it as a criteria integration problem and further present an algorithm based on self-adaptive weighted rank aggregation to achieve a good solution. The efficacy of the proposed method was demonstrated on thousands of mammographic images from the digital database for screening mammography. The labeling costs of obtaining optimal performance in the classification and ordinal regression task respectively fell to 33.8 and 19.8 percent of their original costs. The proposed method also generated 1228 wins, 369 ties and 47 losses for the classification task, and 1933 wins, 258 ties and 185 losses for the ordinal regression task compared to the other state-of-the-art active learning algorithms. By taking the

  11. Mammographic features of breast carcinoma: mammographic-pathologic correlation

    International Nuclear Information System (INIS)

    Gu Yajia; Wang Jiuhua; Chen Tongzhen; Zhang Tingqiu; Zhou Kangrong

    2003-01-01

    Objective: To analyze the mammographic features of breast carcinoma and the correlation between the mammographic and pathologic findings. Methods: A prospective study of 397 consecutive mammograms in patients with breast carcinoma, including infiltrating ductal carcinoma (IDC, n=297), ductal carcinoma in situ (DCIS) and DCIS associated with small invasive foci (n=38), mucinous carcinoma (n=21), medullary carcinoma (n=22) and invasive lobular carcinoma (n=19), was performed to determine the correlations between the mammographic and pathologic findings. Results: (1) Microcalcifications appeared in 170 cases (42.8%), a mass in 258 cases (65.0%), and distortion in 33 cases (8.3%), respectively. (2) Microcalcifications were more commonly associated with DCIS and IDC (χ 2 =30.90, P 2 =30.87, P 2 =27.40, P 2 =6.22, P 2 =7.19, P < 0.01). Conclusion: The common features of breast carcinoma in mammography were microcalcifications, microcalcifications with a mass, a mass, and distortion IDC was the commonest in breast carcinoma, and could be considered when mammographic malignant features above mentioned were found except the appearance of microcalcifications alone, which was firstly suggestive of DCIS. A mass also appeared in medullary and mucinous carcinoma, and distortion appeared in invasive lobular carcinoma

  12. Mammographic findings of women recalled for diagnostic work-up in digital versus screen-film mammography in a population-based screening program

    International Nuclear Information System (INIS)

    Lipasti, Seppo; Pamilo, Martti; Anttila, Ahti

    2010-01-01

    Background: Limited information is available concerning differences in the radiological findings of women recalled for diagnostic work-up in digital mammography (DM) versus screen-film mammography (SFM) screening. Purpose: To compare the radiological findings, their positive predictive values (PPVs) for cancer and other process indicators of DM screening performed by computed radiography (CR) technology and SFM screening in a population-based program. Material and Methods: The material consisted of women, 50-59 years of age, who were invited for screening: 30 153 women with DM in 2007-2008 and 32 939 women with SFM in 1999-2000. The attendance rate was 77.7% (23 440) in the DM arm and 83.8% (27 593) in the SFM arm. In the DM arm, 1.71% of those screened (401) and in the SFM arm 1.59% (438) were recalled for further work-up. The images resulting in the recall were classified as: 1) tumor-like mass, 2) parenchymal distortion/asymmetry, 3) calcifications, and 4) combination of mass and calcifications. The distributions of the various radiological findings and their PPVs for cancer were compared in both study groups. The recall rates, cancer detection rates, test specificities, and PPVs of the DM and SFM groups were also compared. Results: Women were recalled for diagnostic work-up most often due to tumor-like mass. It was more common in SFM (1.08% per woman screened) than in DM (0.93%). The second most common finding was parenchymal distortion and asymmetry, more often in DM (0.58%) than in SFM (0.37%). Calcifications were the third most common finding. DM exposed calcifications more often (0.49%) than SFM (0.26%). The PPVs for cancer of the recalls were higher in DM than in SFM in all subgroups of radiological findings. The test specificities were similar (DM 98.9%, SFM 98.8%). Significantly more cancers were detected by DM (cancer detection rate 0.623% per woman screened, n=146) than by SFM (cancer detection rate 0.406% per woman screened, n=112). The PPVs for

  13. Breast Tissue Composition and Immunophenotype and Its Relationship with Mammographic Density in Women at High Risk of Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Jia-Min B Pang

    Full Text Available To investigate the cellular and immunophenotypic basis of mammographic density in women at high risk of breast cancer.Mammograms and targeted breast biopsies were accrued from 24 women at high risk of breast cancer. Mammographic density was classified into Wolfe categories and ranked by increasing density. The histological composition and immunophenotypic profile were quantified from digitized haematoxylin and eosin-stained and immunohistochemically-stained (ERα, ERβ, PgR, HER2, Ki-67, and CD31 slides and correlated to mammographic density.Increasing mammographic density was significantly correlated with increased fibrous stroma proportion (rs (22 = 0.5226, p = 0.0088 and significantly inversely associated with adipose tissue proportion (rs (22 = -0.5409, p = 0.0064. Contrary to previous reports, stromal expression of ERα was common (19/20 cases, 95%. There was significantly higher stromal PgR expression in mammographically-dense breasts (p=0.026.The proportion of stroma and fat underlies mammographic density in women at high risk of breast cancer. Increased expression of PgR in the stroma of mammographically dense breasts and frequent and unexpected presence of stromal ERα expression raises the possibility that hormone receptor expression in breast stroma may have a role in mediating the effects of exogenous hormonal therapy on mammographic density.

  14. Variations of radiation intensity as a function of position in radiation field of a mammographic unit of 760 mm SID with Mo anode and 20 μm Mo added filter

    International Nuclear Information System (INIS)

    Noriah Jamal

    2001-01-01

    There are many effects that contribute to radiation field nonuniformity in mammography, including the heel effect and shorter source to image distance (SID), inverse square law and different photon path lengths through various attenuating media (the x-ray tube beryllium window, the added filter, the mirror, and the compression paddle) throughout the field. Variations of radiation intensity was investigated as a function of position in the radiation field (with compression paddle in place)of a mammographic unit in 760 mm SID with Mo anode and 20 μm Mo added filter. Reduction in radiation intensity along central axis of up to 19.40%, 19.13% and 19.34% were noted at 24, 26 and 28 kVp respectively. Radiation intensity also drops off to the left and right of the central axis. As a function of position in the field, we also found that the variations of optical density correlate well with the measured radiation intensity changes. (Author)

  15. Improved mammographic interpretation of masses using computer-aided diagnosis

    International Nuclear Information System (INIS)

    Leichter, I.; Fields, S.; Novak, B.; Nirel, R.; Bamberger, P.; Lederman, R.; Buchbinder, S.

    2000-01-01

    The aim of this study was to evaluate the effectiveness of computerized image enhancement, to investigate criteria for discriminating benign from malignant mammographic findings by computer-aided diagnosis (CAD), and to test the role of quantitative analysis in improving the accuracy of interpretation of mass lesions. Forty sequential mammographically detected mass lesions referred for biopsy were digitized at high resolution for computerized evaluation. A prototype CAD system which included image enhancement algorithms was used for a better visualization of the lesions. Quantitative features which characterize the spiculation were automatically extracted by the CAD system for a user-defined region of interest (ROI). Reference ranges for malignant and benign cases were acquired from data generated by 214 known retrospective cases. The extracted parameters together with the reference ranges were presented to the radiologist for the analysis of 40 prospective cases. A pattern recognition scheme based on discriminant analysis was trained on the 214 retrospective cases, and applied to the prospective cases. Accuracy of interpretation with and without the CAD system, as well as the performance of the pattern recognition scheme, were analyzed using receiver operating characteristics (ROC) curves. A significant difference (p z ) increased significantly (p z for the results of the pattern recognition scheme was higher (0.95). The results indicate that there is an improved accuracy of diagnosis with the use of the mammographic CAD system above that of the unassisted radiologist. Our findings suggest that objective quantitative features extracted from digitized mammographic findings may help in differentiating between benign and malignant masses, and can assist the radiologist in the interpretation of mass lesions. (orig.)

  16. Agreement of mammographic measures of volumetric breast density to MRI.

    Directory of Open Access Journals (Sweden)

    Jeff Wang

    Full Text Available Clinical scores of mammographic breast density are highly subjective. Automated technologies for mammography exist to quantify breast density objectively, but the technique that most accurately measures the quantity of breast fibroglandular tissue is not known.To compare the agreement of three automated mammographic techniques for measuring volumetric breast density with a quantitative volumetric MRI-based technique in a screening population.Women were selected from the UCSF Medical Center screening population that had received both a screening MRI and digital mammogram within one year of each other, had Breast Imaging Reporting and Data System (BI-RADS assessments of normal or benign finding, and no history of breast cancer or surgery. Agreement was assessed of three mammographic techniques (Single-energy X-ray Absorptiometry [SXA], Quantra, and Volpara with MRI for percent fibroglandular tissue volume, absolute fibroglandular tissue volume, and total breast volume.Among 99 women, the automated mammographic density techniques were correlated with MRI measures with R(2 values ranging from 0.40 (log fibroglandular volume to 0.91 (total breast volume. Substantial agreement measured by kappa statistic was found between all percent fibroglandular tissue measures (0.72 to 0.63, but only moderate agreement for log fibroglandular volumes. The kappa statistics for all percent density measures were highest in the comparisons of the SXA and MRI results. The largest error source between MRI and the mammography techniques was found to be differences in measures of total breast volume.Automated volumetric fibroglandular tissue measures from screening digital mammograms were in substantial agreement with MRI and if associated with breast cancer could be used in clinical practice to enhance risk assessment and prevention.

  17. Agreement of mammographic measures of volumetric breast density to MRI.

    Science.gov (United States)

    Wang, Jeff; Azziz, Ania; Fan, Bo; Malkov, Serghei; Klifa, Catherine; Newitt, David; Yitta, Silaja; Hylton, Nola; Kerlikowske, Karla; Shepherd, John A

    2013-01-01

    Clinical scores of mammographic breast density are highly subjective. Automated technologies for mammography exist to quantify breast density objectively, but the technique that most accurately measures the quantity of breast fibroglandular tissue is not known. To compare the agreement of three automated mammographic techniques for measuring volumetric breast density with a quantitative volumetric MRI-based technique in a screening population. Women were selected from the UCSF Medical Center screening population that had received both a screening MRI and digital mammogram within one year of each other, had Breast Imaging Reporting and Data System (BI-RADS) assessments of normal or benign finding, and no history of breast cancer or surgery. Agreement was assessed of three mammographic techniques (Single-energy X-ray Absorptiometry [SXA], Quantra, and Volpara) with MRI for percent fibroglandular tissue volume, absolute fibroglandular tissue volume, and total breast volume. Among 99 women, the automated mammographic density techniques were correlated with MRI measures with R(2) values ranging from 0.40 (log fibroglandular volume) to 0.91 (total breast volume). Substantial agreement measured by kappa statistic was found between all percent fibroglandular tissue measures (0.72 to 0.63), but only moderate agreement for log fibroglandular volumes. The kappa statistics for all percent density measures were highest in the comparisons of the SXA and MRI results. The largest error source between MRI and the mammography techniques was found to be differences in measures of total breast volume. Automated volumetric fibroglandular tissue measures from screening digital mammograms were in substantial agreement with MRI and if associated with breast cancer could be used in clinical practice to enhance risk assessment and prevention.

  18. Dissimilarity Application in Digitized Mammographic Images Classification

    Directory of Open Access Journals (Sweden)

    Ubaldo Bottigli

    2006-06-01

    Full Text Available Purpose of this work is the development of an automatic classification system which could be useful for radiologists in the investigation of breast cancer. The software has been designed in the framework of the MAGIC-5 collaboration. In the traditional way of learning from examples of objects the classifiers are built in a feature space. However, an alternative ways can be found by constructing decision rules on dissimilarity (distance representations. In such a recognition process a new object is described by its distances to (a subset of the training samples. The use of the dissimilarities is especially of interest when features are difficult to obtain or when they have a little discriminative power. In the automatic classification system the suspicious regions with high probability to include a lesion are extracted from the image as regions of interest (ROIs. Each ROI is characterized by some features extracted from co-occurrence matrix containing spatial statistics information on ROI pixel grey tones. A dissimilarity representation of these features is made before the classification. A feed-forward neural network is employed to distinguish pathological records, from non-pathological ones by the new features. The results obtained in terms of sensitivity and specificity will be presented.

  19. Scattering influence in mammographic image

    International Nuclear Information System (INIS)

    Poletti, Martin Eduardo; Almeida, Adelaide de

    1996-01-01

    The quantification of mammographic images affected by scattered radiation is studied. The average glandular dose as a function of kVp and breast thickness for breast composition 50/50% is also evaluated. The results show that the contrast decreases with increasing of kVp and breast thickness, and the average glandular dose increase with increasing breast thickness and decreases with increasing kVp

  20. Relationship between breast sound speed and mammographic percent density

    Science.gov (United States)

    Sak, Mark; Duric, Nebojsa; Boyd, Norman; Littrup, Peter; Myc, Lukasz; Faiz, Muhammad; Li, Cuiping; Bey-Knight, Lisa

    2011-03-01

    Despite some shortcomings, mammography is currently the standard of care for breast cancer screening and diagnosis. However, breast ultrasound tomography is a rapidly developing imaging modality that has the potential to overcome the drawbacks of mammography. It is known that women with high breast densities have a greater risk of developing breast cancer. Measuring breast density is accomplished through the use of mammographic percent density, defined as the ratio of fibroglandular to total breast area. Using an ultrasound tomography (UST) prototype, we created sound speed images of the patient's breast, motivated by the fact that sound speed in a tissue is proportional to the density of the tissue. The purpose of this work is to compare the acoustic performance of the UST system with the measurement of mammographic percent density. A cohort of 251 patients was studied using both imaging modalities and the results suggest that the volume averaged breast sound speed is significantly related to mammographic percent density. The Spearman correlation coefficient was found to be 0.73 for the 175 film mammograms and 0.69 for the 76 digital mammograms obtained. Since sound speed measurements do not require ionizing radiation or physical compression, they have the potential to form the basis of a safe, more accurate surrogate marker of breast density.

  1. 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.

  2. 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

  3. Comparative study of radiation dose between digital panoramic X-ray unit and general panoramic X-ray unit

    International Nuclear Information System (INIS)

    Li Qingshan; Duan Tao; Wang Xiaoyun; Zhao Li; Dong Jian; Wei Lei

    2010-01-01

    Objective: To compare the actual dose of patients who receive the same medical practice by either digital panoramic X-ray unit and general panoramic X-ray unit and give evidence for better selection of oral X-ray examination method. Methods: Round sheet lithium fluoride (LiF) thermoluminescent dosimeters (TLD) were used. The experiment was divided into natural background contrast group, general panoramic X-ray children group, general panoramic X-ray adults group, digital panoramic X-ray children group and digital panoramic X-ray adults group. The dosimeter of natural background radiation was placed at the office of the doctor, the dosimeters of general panoramic X-ray children group and general panoramic X-ray adults group were irradiated by different conditions according to the clinical application of panoramic X-ray to children and adults, the dosimeters of digital panoramic X-ray children group and digital panoramic X-ray adults group were irradiated by different conditions according to the clinical application of digital panoramic X-ray to children and adults. The thermoluminescent dosimeter was used to count and calculate the exposure doses in various groups. Results: The dose of children exposed in general panoramic X-ray unit was 1.28 times of that in digital panoramic X-ray unit, there was significant difference (t=6.904, P<0.01). The dose of adults exposed in general panoramic X-ray unit was 1.55 times of that in the digital panoramic X-ray unit, there also was significant difference (t=-11.514. P< 0.01). Conclusion: The digital panoramic X-ray unit can reduce the dose of patients, so the digital panoramic X-ray unit should be used as far as possible. (authors)

  4. EnviroAtlas - Percent Urban Land Cover by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the percent urban land for each 12-digit hydrologic unit code (HUC) in the conterminous United States. For the purposes of this...

  5. Generation of CR mammographic image for evaluation quality parameters

    International Nuclear Information System (INIS)

    Flores, Mabel B.; Mourao, Arnaldo P.; Centro Federal de Educacao Tecnologica de Minas Gerais

    2017-01-01

    Currently, among the diseases most feared by women, breast cancer ranks first in the world with an incidence of more than 1.6 million cases and a mortality of more than 521.9 thousand cases by year, which makes this disease the type of cancer with higher incidence and mortality compared to the other types of cancer that mainly affect the female gender, without considering non-melanoma skin cancer. In Brazil, more than 14.4 thousand deaths were registered in 2013 and more than 57 thousand new cases were estimated for 2016. The use of computerized radiography (CR) for the generation of mammographic digital images is widely used in Brazil for the screening of breast cancer. The aim of this investigation is to study the variation of CR plate response to exposure to X-ray beams in a mammography unit. Two CR plates from different manufacturers and a compressed breast phantom containing calcium carbonate structures of different sizes simulating calcifications were used for this study. An X-ray beam generated by 30 kV was selected to realize successive exposures of each plate by performing a time variation of 0.5 to 3.5 s, obtaining the raw images. The acquired images were evaluated with the ImageJ software to determine the saturation time of the plates when exposed to X-ray beams and the qualitative resolution of each plate. The plates were found to saturate at different times when exposed under the same conditions to X-ray beams. By means of the images acquired with the breast phantom, it was possible to observe only structures of calcium carbonate with sizes greater than 177 μm. (author)

  6. Generation of CR mammographic image for evaluation quality parameters

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Mabel B.; Mourao, Arnaldo P., E-mail: mbustos@ufmg.br, E-mail: apratabhz@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Centro de Engenharia Politecnica

    2017-11-01

    Currently, among the diseases most feared by women, breast cancer ranks first in the world with an incidence of more than 1.6 million cases and a mortality of more than 521.9 thousand cases by year, which makes this disease the type of cancer with higher incidence and mortality compared to the other types of cancer that mainly affect the female gender, without considering non-melanoma skin cancer. In Brazil, more than 14.4 thousand deaths were registered in 2013 and more than 57 thousand new cases were estimated for 2016. The use of computerized radiography (CR) for the generation of mammographic digital images is widely used in Brazil for the screening of breast cancer. The aim of this investigation is to study the variation of CR plate response to exposure to X-ray beams in a mammography unit. Two CR plates from different manufacturers and a compressed breast phantom containing calcium carbonate structures of different sizes simulating calcifications were used for this study. An X-ray beam generated by 30 kV was selected to realize successive exposures of each plate by performing a time variation of 0.5 to 3.5 s, obtaining the raw images. The acquired images were evaluated with the ImageJ software to determine the saturation time of the plates when exposed to X-ray beams and the qualitative resolution of each plate. The plates were found to saturate at different times when exposed under the same conditions to X-ray beams. By means of the images acquired with the breast phantom, it was possible to observe only structures of calcium carbonate with sizes greater than 177 μm. (author)

  7. Applying a new mammographic imaging marker to predict breast cancer risk

    Science.gov (United States)

    Aghaei, Faranak; Danala, Gopichandh; Hollingsworth, Alan B.; Stoug, Rebecca G.; Pearce, Melanie; Liu, Hong; Zheng, Bin

    2018-02-01

    Identifying and developing new mammographic imaging markers to assist prediction of breast cancer risk has been attracting extensive research interest recently. Although mammographic density is considered an important breast cancer risk, its discriminatory power is lower for predicting short-term breast cancer risk, which is a prerequisite to establish a more effective personalized breast cancer screening paradigm. In this study, we presented a new interactive computer-aided detection (CAD) scheme to generate a new quantitative mammographic imaging marker based on the bilateral mammographic tissue density asymmetry to predict risk of cancer detection in the next subsequent mammography screening. An image database involving 1,397 women was retrospectively assembled and tested. Each woman had two digital mammography screenings namely, the "current" and "prior" screenings with a time interval from 365 to 600 days. All "prior" images were originally interpreted negative. In "current" screenings, these cases were divided into 3 groups, which include 402 positive, 643 negative, and 352 biopsy-proved benign cases, respectively. There is no significant difference of BIRADS based mammographic density ratings between 3 case groups (p cancer detection in the "current" screening. Study demonstrated that this new imaging marker had potential to yield significantly higher discriminatory power to predict short-term breast cancer risk.

  8. Ultrasound detection of nonpalpable mammographically occult malignancy

    International Nuclear Information System (INIS)

    Simpson, W.L.; Hermann, G.; Rausch, D.R.; Sherman, J.; Feig, S.A.; Bleiweiss, I.J.; Jaffer, S.

    2008-01-01

    To evaluate the prevalence of occult malignancy with screening breast ultrasound. All ultrasound-guided core needle breast biopsies performed between January 1, 1999, and June 30, 2001, were retrospectively reviewed. Lesions were identified during screening breast ultrasound in high-risk women with no mammographic or palpable abnormality in either breast, a unilateral mammographic or palpable abnormality in the contralateral breast, or a unilateral mammographic or palpable abnormality in a different quadrant of the same breast. All ultrasound-detected lesions were histologically verified. Six hundred and fifty-two women with a mean age of 49 years underwent 698 biopsies during the study period. Three hundred and forty-nine of these lesions were detected at screening breast ultrasound. Out of 349, 11 (3.2%) had a mammographically and clinically occult malignancy. Nine cancers were found in women with no mammographic or palpable abnormality. Two cancers were found in the same breast as the mammographic or palpable abnormality. None were found in the breast contralateral to a palpable or mammographic abnormality. Screening breast ultrasound of high-risk women has a similar detection rate for occult carcinoma as screening mammography, but has a low positive predictive value in cases where biopsy is performed. (author)

  9. Scatter radiation intensities around a clinical digital breast tomosynthesis unit and the impact on radiation shielding considerations

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kai, E-mail: kyang11@mgh.harvard.edu; Li, Xinhua; Liu, Bob [Division of Diagnostic Imaging Physics, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114 (United States)

    2016-03-15

    Purpose: To measure the scattered radiation intensity around a clinical digital breast tomosynthesis (DBT) unit and to provide updated data for radiation shielding design for DBT systems with tungsten-anode x-ray tubes. Methods: The continuous distribution of scattered x-rays from a clinical DBT system (Hologic Selenia Dimensions) was measured within an angular range of 0°–180° using a linear-array x-ray detector (X-Scan 0.8f3-512, Detection Technology, Inc., Finland), which was calibrated for the x-ray spectrum range of the DBT unit. The effects of x-ray field size, phantom size, and x-ray kVp/filter combination were investigated. Following a previously developed methodology by Simpkin, scatter fraction was determined for the DBT system as a function of angle around the phantom center. Detailed calculations of the scatter intensity from a DBT system were demonstrated using the measured scatter fraction data. Results: For the 30 and 35 kVp acquisition, the scatter-to-primary-ratio and scatter fraction data closely matched with data previously measured by Simpkin. However, the measured data from this study demonstrated the nonisotropic distribution of the scattered radiation around a DBT system, with two strong peaks around 25° and 160°. The majority scatter radiation (>70%) originated from the imaging detector assembly, instead of the phantom. With a workload from a previous survey performed at MGH, the scatter air kerma at 1 m from the phantom center for wall/door is 1.76 × 10{sup −2} mGy patient{sup −1}, for floor is 1.64 × 10{sup −1} mGy patient{sup −1}, and for ceiling is 3.66 × 10{sup −2} mGy patient{sup −1}. Conclusions: Comparing to previously measured data for mammographic systems, the scatter air kerma from Holgoic DBT is at least two times higher. The main reasons include the harder primary beam with higher workload (measured with total mAs/week), added tomosynthesis acquisition, and strong small angle forward scattering. Due to the

  10. Improved mammographic interpretation of masses using computer-aided diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Leichter, I. [Dept. of Electro-Optics, Jerusalem College of Technology (Israel); Fields, S.; Novak, B. [Dept. of Radiology, Hadassah University Hospital, Mt. Scopus Jerusalem (Israel); Nirel, R. [Dept. of Statistics, Hebrew University of Jerusalem, Mt. Scopus, Jerusalem (Israel); Bamberger, P. [Dept. of Electronics, Jerusalem College of Technology, Jerusalem (Israel); Lederman, R. [Department of Radiology, Hadassah University Hospital, Ein Kerem, Jerusalem (Israel); Buchbinder, S. [Department of Radiology, Montefiore Medical Center, University Hospital for the Albert Einstein College of Medicine, Bronx, New York (United States)

    2000-02-01

    The aim of this study was to evaluate the effectiveness of computerized image enhancement, to investigate criteria for discriminating benign from malignant mammographic findings by computer-aided diagnosis (CAD), and to test the role of quantitative analysis in improving the accuracy of interpretation of mass lesions. Forty sequential mammographically detected mass lesions referred for biopsy were digitized at high resolution for computerized evaluation. A prototype CAD system which included image enhancement algorithms was used for a better visualization of the lesions. Quantitative features which characterize the spiculation were automatically extracted by the CAD system for a user-defined region of interest (ROI). Reference ranges for malignant and benign cases were acquired from data generated by 214 known retrospective cases. The extracted parameters together with the reference ranges were presented to the radiologist for the analysis of 40 prospective cases. A pattern recognition scheme based on discriminant analysis was trained on the 214 retrospective cases, and applied to the prospective cases. Accuracy of interpretation with and without the CAD system, as well as the performance of the pattern recognition scheme, were analyzed using receiver operating characteristics (ROC) curves. A significant difference (p < 0.005) was found between features extracted by the CAD system for benign and malignant cases. Specificity of the CAD-assisted diagnosis improved significantly (p < 0.02) from 14 % for the conventional assessment to 50 %, and the positive predictive value increased from 0.47 to 0.62 (p < 0.04). The area under the ROC curve (A{sub z}) increased significantly (p < 0.001) from 0.66 for the conventional assessment to 0.81 for the CAD-assisted analysis. The A{sub z} for the results of the pattern recognition scheme was higher (0.95). The results indicate that there is an improved accuracy of diagnosis with the use of the mammographic CAD system above that

  11. Nonpalpable breast cancer : mammographic and clinical findings

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jae Seung; Kim, Eun Kyung; Oh, Ki Keun; Cheon, Young Jik; Lee, Byung Chan [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1998-08-01

    To evaluate the mammographic and clinical findings of nonpalpable breast cancer. Materials and Methods : In 28 of 607 breast cancer patients examined between January 1994 and April 1997, lesions were nonpalpable. We retrospectively analyzed the mammographic, clinical and pathologic features of 25 patients (28 lesions) whose mammograms we obtained. Results : Among these 25 patients (28 lesions) screening was abnormal in 22; other symptoms were bloody nipple discharge(n=4), and nipple eczema(n=2). The patients were 34-62 (mean 52)years old. Invasive ductal carcinoma(n=13), DCIS(ductal carcinoma in situ, n-12), Paget's disease (n=2), and LCIS(lobular carcinoma in situ, n=1) were found during surgery. Six of 28 lesions(21%) showed evidence of axillary nodal metastasis;the majority arose from the upper outer quadrant of the breast (n=21). The mammographic findings were mass (50%), (and mass with microcalcification, 11%); microcalcification(29%); asymmetrical density(14%); and normal (7%). According to the mammographic density of breast parenchyma, the major finding in the low density group(N1+P1) was mass(9/9), and in the high density group(P2+DY) was microcalcification (12/19). Conclusion : The most common mammographic findings of nonpalpable breast cancer were mass (50%) and microcalcification(29%). Its features varied according to the mammographic density of breast parenchyma;mass was the main finding in the low density group and microcalcification in the high density group.

  12. Nonpalpable breast cancer : mammographic and clinical findings

    International Nuclear Information System (INIS)

    Seo, Jae Seung; Kim, Eun Kyung; Oh, Ki Keun; Cheon, Young Jik; Lee, Byung Chan

    1998-01-01

    To evaluate the mammographic and clinical findings of nonpalpable breast cancer. Materials and Methods : In 28 of 607 breast cancer patients examined between January 1994 and April 1997, lesions were nonpalpable. We retrospectively analyzed the mammographic, clinical and pathologic features of 25 patients (28 lesions) whose mammograms we obtained. Results : Among these 25 patients (28 lesions) screening was abnormal in 22; other symptoms were bloody nipple discharge(n=4), and nipple eczema(n=2). The patients were 34-62 (mean 52)years old. Invasive ductal carcinoma(n=13), DCIS(ductal carcinoma in situ, n-12), Paget's disease (n=2), and LCIS(lobular carcinoma in situ, n=1) were found during surgery. Six of 28 lesions(21%) showed evidence of axillary nodal metastasis;the majority arose from the upper outer quadrant of the breast (n=21). The mammographic findings were mass (50%), (and mass with microcalcification, 11%); microcalcification(29%); asymmetrical density(14%); and normal (7%). According to the mammographic density of breast parenchyma, the major finding in the low density group(N1+P1) was mass(9/9), and in the high density group(P2+DY) was microcalcification (12/19). Conclusion : The most common mammographic findings of nonpalpable breast cancer were mass (50%) and microcalcification(29%). Its features varied according to the mammographic density of breast parenchyma;mass was the main finding in the low density group and microcalcification in the high density group

  13. Digital protection in power plants. Electrical unit and line protection. Digital protection systems for NPP

    International Nuclear Information System (INIS)

    Kaczmarek, A.

    2000-01-01

    In this presentation author deals with the digital protection systems for nuclear power plants. The evolution of protection devices, protection concept for power plants, concept of functional redundancy, references for digital protection, benefits for the customer well as concept fault recorder are presented. (author)

  14. EnviroAtlas - Historic Places by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each 12-digit Hydrologic Unit (HUC). The historic places data were compiled from...

  15. Results of pilot project on introducing quality control of mammographic equipment

    International Nuclear Information System (INIS)

    Vasileva, Zh.; Lichev, A.; Dimov, A.; Kostova, E.; Dimov, G.

    2003-01-01

    Objective:The results from a pilot project, realized in the framework of the PHARE Project 'Radiation Protection and Safety in Medical Use of the Ionizing Radiation'. The main goal of the project is the elaboration a quality control program for mammographic equipment and its implementation in 4 radiological units in the country. Another task is to examine the possibility for conducting a mammographic screening using this equipment. Material and methods: The developed quality control program has the following components: test parameters; criteria for intervention; minimal frequency of measurement. Methodologies for measurement of the parameters and assessment of the results in accordance with the European Protocol for physical and technical aspects of the mammographic screening. Standard protocols have been elaborated. Results: The quality program has been tested for three month at different hospitals. Conclusions: Optimization and strict control of the process of film development are needed. The exposure equipment. The quality control program should be implemented on all mammographic equipment in the country. For the performance of mammographic screening a strict selection of the equipment is necessary

  16. Apple Pay & Digital Wallets in Mexico and the United States: Illusion or Financial Revolution?

    OpenAIRE

    Heredia Salazar, Ricardo

    2017-01-01

    Abstract: Apple Pay and digital wallets have gained popularity since the fall of 2014. Perceiving Apple Pay & digital wallets as a financial revolution at this moment might be a mistake. The following study shows that it is just the evolution of a payment system in Mexico and the United States of America, a system that opened the door to a possible future financial revolution. Current financial regulation in Mexico and the United States of America is not accurately applied; therefore, proper ...

  17. Stratification of mammographic computerized analysis by BI-RADS categories

    Energy Technology Data Exchange (ETDEWEB)

    Lederman, Richard [Department of Radiology, Hadassah University Hospital, Ein Kerem, Jerusalem (Israel); Leichter, Isaac [Department of Electro-Optics, Jerusalem College of Technology, P.O.B. 16031, Jerusalem (Israel); Buchbinder, Shalom [Department of Radiology of The Montefiore Medical Center, The University Hospital for the Albert Einstein College of Medicine, Bronx, New York (United States); Novak, Boris [Department of Applied Mathematics, Jerusalem College of Technology, P.O.B. 16031, Jerusalem 91160 (Israel); Bamberger, Philippe [Department of Electronics, Jerusalem College of Technology, POB 16031, Jerusalem (Israel); Fields, Scott [Department of Radiology, Hadassah University Hospital, Mt. Scopus, Jerusalem (Israel)

    2003-02-01

    The Breast Imaging Reporting and Data System (BI-RADS) was implemented to standardize characterization of mammographic findings. The purpose of the present study was to evaluate in which BI-RADS categories the changes recommended by computerized mammographic analysis are most beneficial. Archival cases including, 170 masses (101 malignant, 69 benign) and 63 clusters of microcalcifications (MCs; 36 malignant, 27 benign), were evaluated retrospectively, using the BI-RADS categories, by several radiologists, blinded to the pathology results. A computerized system then automatically extracted from the digitized mammogram features characterizing mammographic lesions, which were used to classify the lesions. The results of the computerized classification scheme were compared, by receiver operating characteristics (ROC) analysis, to the conventional interpretation. In the ''low probability of malignancy group'' (excluding BI-RADS categories 4 and 5), computerized analysis improved the A{sub z}of the ROC curve significantly, from 0.57 to 0.89. In the ''high probability of malignancy group'' (mostly category 5) the computerized analysis yielded an ROC curve with an A {sub z}of 0.99. In the ''intermediate probability of malignancy group'' computerized analysis improved the A {sub z}significantly, from 0.66 for to 0.83. Pair-wise analysis showed that in the latter group the modifications resulting from computerized analysis were correct in 83% of cases. Computerized analysis has the ability to improve the performance of the radiologists exactly in the BI-RADS categories with the greatest difficulties in arriving at a correct diagnosis. It increased the performance significantly in the problematic group of ''intermediate probability of malignancy'' and pinpointed all the cases with missed cancers in the ''low probability'' group. (orig.)

  18. Stratification of mammographic computerized analysis by BI-RADS categories

    International Nuclear Information System (INIS)

    Lederman, Richard; Leichter, Isaac; Buchbinder, Shalom; Novak, Boris; Bamberger, Philippe; Fields, Scott

    2003-01-01

    The Breast Imaging Reporting and Data System (BI-RADS) was implemented to standardize characterization of mammographic findings. The purpose of the present study was to evaluate in which BI-RADS categories the changes recommended by computerized mammographic analysis are most beneficial. Archival cases including, 170 masses (101 malignant, 69 benign) and 63 clusters of microcalcifications (MCs; 36 malignant, 27 benign), were evaluated retrospectively, using the BI-RADS categories, by several radiologists, blinded to the pathology results. A computerized system then automatically extracted from the digitized mammogram features characterizing mammographic lesions, which were used to classify the lesions. The results of the computerized classification scheme were compared, by receiver operating characteristics (ROC) analysis, to the conventional interpretation. In the ''low probability of malignancy group'' (excluding BI-RADS categories 4 and 5), computerized analysis improved the A z of the ROC curve significantly, from 0.57 to 0.89. In the ''high probability of malignancy group'' (mostly category 5) the computerized analysis yielded an ROC curve with an A z of 0.99. In the ''intermediate probability of malignancy group'' computerized analysis improved the A z significantly, from 0.66 for to 0.83. Pair-wise analysis showed that in the latter group the modifications resulting from computerized analysis were correct in 83% of cases. Computerized analysis has the ability to improve the performance of the radiologists exactly in the BI-RADS categories with the greatest difficulties in arriving at a correct diagnosis. It increased the performance significantly in the problematic group of ''intermediate probability of malignancy'' and pinpointed all the cases with missed cancers in the ''low probability'' group. (orig.)

  19. Watershed Boundaries - WATERSHEDS_HUC06_USGS_IN: 6-Digit Accounting Units, Hydrologic Units, in Indiana, (Derived from US Geological Survey, 1:24,000 Polygon Shapefile)

    Data.gov (United States)

    NSGIC State | GIS Inventory — WATERSHEDS_HUC06_USGS_IN is a polygon shapefile showing the boundaries of accounting units (HUA) in Indiana. Accounting units are noted by a 6-digit hydrologic unit....

  20. Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    /processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital......Digital micro-controllers/processors enable the cost-effective control of grid-connected power converter systems in terms of system monitoring, signal processing (e.g., grid synchronization), control (e.g., grid current and voltage control), etc. Normally, the control is implemented in a micro-controller...

  1. Force balancing in mammographic compression

    International Nuclear Information System (INIS)

    Branderhorst, W.; Groot, J. E. de; Lier, M. G. J. T. B. van; Grimbergen, C. A.; Neeter, L. M. F. H.; Heeten, G. J. den; Neeleman, C.

    2016-01-01

    Purpose: In mammography, the height of the image receptor is adjusted to the patient before compressing the breast. An inadequate height setting can result in an imbalance between the forces applied by the image receptor and the paddle, causing the clamped breast to be pushed up or down relative to the body during compression. This leads to unnecessary stretching of the skin and other tissues around the breast, which can make the imaging procedure more painful for the patient. The goal of this study was to implement a method to measure and minimize the force imbalance, and to assess its feasibility as an objective and reproducible method of setting the image receptor height. Methods: A trial was conducted consisting of 13 craniocaudal mammographic compressions on a silicone breast phantom, each with the image receptor positioned at a different height. The image receptor height was varied over a range of 12 cm. In each compression, the force exerted by the compression paddle was increased up to 140 N in steps of 10 N. In addition to the paddle force, the authors measured the force exerted by the image receptor and the reaction force exerted on the patient body by the ground. The trial was repeated 8 times, with the phantom remounted at a slightly different orientation and position between the trials. Results: For a given paddle force, the obtained results showed that there is always exactly one image receptor height that leads to a balance of the forces on the breast. For the breast phantom, deviating from this specific height increased the force imbalance by 9.4 ± 1.9 N/cm (6.7%) for 140 N paddle force, and by 7.1 ± 1.6 N/cm (17.8%) for 40 N paddle force. The results also show that in situations where the force exerted by the image receptor is not measured, the craniocaudal force imbalance can still be determined by positioning the patient on a weighing scale and observing the changes in displayed weight during the procedure. Conclusions: In mammographic breast

  2. Performance evaluation of a digital mammography unit using a contrast-detail phantom

    Science.gov (United States)

    Elizalde-Cabrera, J.; Brandan, M.-E.

    2015-01-01

    The relation between image quality and mean glandular dose (MGD) has been studied for a Senographe 2000D mammographic unit used for research in our laboratory. The magnitudes were evaluated for a clinically relevant range of acrylic thicknesses and radiological techniques. The CDMAM phantom was used to determine the contrast-detail curve. Also, an alternative method based on the analysis of signal-to-noise (SNR) and contrast-to-noise (CNR) ratios from the CDMAM image was proposed and applied. A simple numerical model was utilized to successfully interpret the results. Optimum radiological techniques were determined using the figures-of-merit FOMSNR=SNR2/MGD and FOMCNR=CNR2/MGD. Main results were: the evaluation of the detector response flattening process (it reduces by about one half the spatial non-homogeneities due to the X- ray field), MGD measurements (the values comply with standards), and verification of the automatic exposure control performance (it is sensitive to fluence attenuation, not to contrast). For 4-5 cm phantom thicknesses, the optimum radiological techniques were Rh/Rh 34 kV to optimize SNR, and Rh/Rh 28 kV to optimize CNR.

  3. Mammographic appearances of male breast disease.

    Science.gov (United States)

    Appelbaum, A H; Evans, G F; Levy, K R; Amirkhan, R H; Schumpert, T D

    1999-01-01

    Various male breast diseases have characteristic mammographic appearances that can be correlated with their pathologic diagnoses. Male breast cancer is usually subareolar and eccentric to the nipple. Margins of the lesions are more frequently well defined, and calcifications are rarer and coarser than those occurring in female breast cancer. Gynecomastia usually appears as a fan-shaped density emanating from the nipple, gradually blending into surrounding fat. It may have prominent extensions into surrounding fat and, in some cases, an appearance similar to that of a heterogeneously dense female breast. Although there are characteristic mammographic features that allow breast cancer in men to be recognized, there is substantial overlap between these features and the mammographic appearance of benign nodular lesions. The mammographic appearance of gynecomastia is not similar to that of male breast cancer, but in rare cases, it can mask malignancy. Gynecomastia can be mimicked by chronic inflammation. All mammographically lucent lesions of the male breast appear to be benign, similar to such lesions in the female breast.

  4. Mammographic Texture Resemblance generalizes as an independent risk factor of breast cancer

    DEFF Research Database (Denmark)

    Chernoff, Konstantin; Christopher, S G; Karemore, Gopal

    PURPOSE Breast density has been established as a risk factor of breast cancer in numerous studies. Mammographic Texture Resemblance (MTR) has shown to be a density independent risk factor, but only on a single study. We examine if the statistics of the texture recorded in one study generalize...... as an independent risk factor in an unrelated cohort. METHOD AND MATERIALS The statistics of texture were recorded in digitalized film-mammograms of one 4-year prospective study (S1, Dutch screening program) of 245 breast cancers and 250 matched controls. From an independent cohort study (S2, Mayo Mammography...... Health Study cohort) 226 incident breast cancer cases diagnosed through 2008 and 442 matched controls (on age) were used for scoring screening digitized mammograms that were ascertained years prior to diagnosis 1993-2006. Mammographic percent density (PD), using Cumulus, and other major risk factors were...

  5. Epidemiologic Studies of Isoflavones & Mammographic Density

    Science.gov (United States)

    Maskarinec, Gertraud; Verheus, Martijn; Tice, Jeffrey A.

    2010-01-01

    Isoflavones, phytoestrogens in soy beans with estrogen-like properties, have been examined for their cancer protective effects. Mammographic density is a strong predictor of breast cancer. This review summarizes studies that have examined the association between isoflavones and breast density. Observational investigations in Hawaii and Singapore suggest slightly lower breast density among women of Asian descent with regular soy intake, but two larger studies from Japan and Singapore did not observe a protective effect. The findings from seven randomized trials with primarily Caucasian women indicate that soy or isoflavones do not modify mammographic density. Soy foods and isoflavone supplements within a nutritional range do not appear to modify breast cancer risk as assessed by mammographic density. PMID:22253990

  6. Epidemiologic Studies of Isoflavones & Mammographic Density

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Tice

    2010-01-01

    Full Text Available Isoflavones, phytoestrogens in soy beans with estrogen-like properties, have been examined for their cancer protective effects. Mammographic density is a strong predictor of breast cancer. This review summarizes studies that have examined the association between isoflavones and breast density. Observational investigations in Hawaii and Singapore suggest slightly lower breast density among women of Asian descent with regular soy intake, but two larger studies from Japan and Singapore did not observe a protective effect. The findings from seven randomized trials with primarily Caucasian women indicate that soy or isoflavones do not modify mammographic density. Soy foods and isoflavone supplements within a nutritional range do not appear to modify breast cancer risk as assessed by mammographic density.

  7. Indications and guidelines for mammographic examinations

    International Nuclear Information System (INIS)

    Kalisher, L.; Schaffer, D.

    1977-01-01

    The value of mammography in evaluating the asymptomatic patient has been clearly demonstrated by the HIP program, as well as the National Cancer Institute's breast demonstration projects. A one-third reduction in mortality from breast cancer in mammographically screened women has been substantiated. Nonetheless, questions concerning the long-term effects of repeated radiation exposure associated with mammography have been raised, and for this reason judicious selection of women is urged. In general, women who are asymptomatic or at high risk for breast carcinoma should be evaluated with a planned regimen. Mammographic guidelines and recommendations for attaining the greatest benefit at the lowest possible risk are suggested

  8. Mammographic dose survey in the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Novak, Leos [National Radiation Protection Institute, Prague (Czech Republic); Rada, Jiri [National Radiation Protection Institute, Ostrava (Czech Republic)

    2006-07-01

    At present, it is generally accepted that the average dose to the glandular tissue is the most reasonable dose descriptor in mammography with regard to the risk of breast cancer induced by ionizing radiation. It is advantageous to use the quantity mean glandular dose M.G.D. for setting of diagnostic reference levels (D.R.L.) as well, although the quantity is not directly measurable as it is the case of D.R.L. quantities for other imaging modalities. The reason is that a directly measurable quantity suitable for mammography, incident air kerma Ki, depends a lot on a beam quality. The influence of the beam quality (expressed by tube voltage, half value layer and combination of anode/filter material) is already included in calculation of mean glandular dose. To assess a radiation burden of patients due to mammography at a national level a representative dose survey is needed to carry out. Such a study provides statistically significant dose data for setting of the national diagnostic reference levels. National Radiation Protection Institute is performing the study in the Czech Republic since the year 2005.On a basis of presented data, it could be concluded, that the situation in the Czech Republic with respect to patient doses in mammography is encouraging and that the requirements of European Commission are well fulfilled. However, it is obvious, that the obtained results can not be considered as statistically significant at the moment, because the data were not collected from a representative sample of centers, which should observe a distribution of X-ray unit types, type of a mammographic center (screening/non screening ones) and also a locality of a center. The dose survey still continues to cover the whole Czech Republic with the main task to determine new national diagnostic reference levels and to find out optimized standards for carrying out the examinations with respect to patient doses and image quality. (authors)

  9. Mammographic dose survey in the Czech Republic

    International Nuclear Information System (INIS)

    Novak, Leos; Rada, Jiri

    2006-01-01

    At present, it is generally accepted that the average dose to the glandular tissue is the most reasonable dose descriptor in mammography with regard to the risk of breast cancer induced by ionizing radiation. It is advantageous to use the quantity mean glandular dose M.G.D. for setting of diagnostic reference levels (D.R.L.) as well, although the quantity is not directly measurable as it is the case of D.R.L. quantities for other imaging modalities. The reason is that a directly measurable quantity suitable for mammography, incident air kerma Ki, depends a lot on a beam quality. The influence of the beam quality (expressed by tube voltage, half value layer and combination of anode/filter material) is already included in calculation of mean glandular dose. To assess a radiation burden of patients due to mammography at a national level a representative dose survey is needed to carry out. Such a study provides statistically significant dose data for setting of the national diagnostic reference levels. National Radiation Protection Institute is performing the study in the Czech Republic since the year 2005.On a basis of presented data, it could be concluded, that the situation in the Czech Republic with respect to patient doses in mammography is encouraging and that the requirements of European Commission are well fulfilled. However, it is obvious, that the obtained results can not be considered as statistically significant at the moment, because the data were not collected from a representative sample of centers, which should observe a distribution of X-ray unit types, type of a mammographic center (screening/non screening ones) and also a locality of a center. The dose survey still continues to cover the whole Czech Republic with the main task to determine new national diagnostic reference levels and to find out optimized standards for carrying out the examinations with respect to patient doses and image quality. (authors)

  10. Mammographic surveillance in the follow up of early primary breast cancer in England: A cross-sectional survey

    International Nuclear Information System (INIS)

    Greenwood-Haigh, Lesley

    2009-01-01

    Purpose: The aim of this study was to determine current practice in the clinical setting at national and regional level of the use of mammographic surveillance in the follow up of patients surgically treated for early breast cancer. Method: A cross-sectional survey method was employed. Self-administered questionnaires were sent to a random selection of symptomatic breast imaging units representing all the cancer networks in England nationally, and all symptomatic breast imaging units in one cancer network regionally. Questions were designed to determine frequency and duration of mammographic surveillance for patients aged < 50 years and ≥50 years surgically treated by mastectomy or breast conserving surgery and the number of units with protocols based on the risk of local recurrence or development of a new primary breast cancer. Results: The protocols demonstrated a striking diversity in both the frequency and duration of mammographic surveillance; however the variation was less marked regionally. The duration of mammography for patient's aged ≥70 years surgically treated by mastectomy, demonstrated the greatest diversity (range: 0-15 years). Four protocols had regimes tailored to risk. Conclusion: The introduction of protocols based on risk of development of a local recurrence or new primary could prove cost effective by targeting mammographic surveillance to those who would benefit the most. The survey has demonstrated that a 'post-code lottery' exists for both the frequency and duration of mammographic surveillance in this patient group indicating an urgent need for evidence based national guidance.

  11. Mammographic varicosities indicative of a superior mediastinal ...

    African Journals Online (AJOL)

    In addition, an abnormal calibre of the superficial veins can reflect not only underrying breast pathology, but a collateral venous return resulting from an upper mediastinal obstruction. A case mammographically demonstrating mammary varicosities resulting from a superior mediastinal syndrome is described. S. Afr. Med.

  12. State supervision of SONS in the mammographic departments

    International Nuclear Information System (INIS)

    Jursikova, E.; Kodl, O.

    2008-01-01

    State Office for Nuclear Safety has been performed the state supervision over radiation protection at all mammographic centres in the Czech Republic. Inspections are carried out on the basis of requirements of: Act No. 18/1997 Coll., Atomic Act, subsequently amended; Act No. 552/1991 Coll., Supervision Act, subsequently amended; Decree No. 307 /2002 Coll., On radiation protection, as amended by Decree No. 499/2005 Coll. 137 mammography X-ray units have been used actively by 108 independent licensees since 1 September 2008. The mammography screening program started in September 2002. The screening program was carried out at 59 working places last year and already at 66 workplaces with accreditation from 1 up to 3 years this year. The activity of the centres is monitored and inspected continuously (not only by SONS). Inspections at 35 workplaces were carried out last year .The doses are significantly below guidance levels at major part of working places. Most of detected defects were eliminated after inspections. The quality of mammographic workplaces in the Czech Republic has been gradually increased and improved. (authors)

  13. 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.

  14. 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

  15. Classified one-step high-radix signed-digit arithmetic units

    Science.gov (United States)

    Cherri, Abdallah K.

    1998-08-01

    High-radix number systems enable higher information storage density, less complexity, fewer system components, and fewer cascaded gates and operations. A simple one-step fully parallel high-radix signed-digit arithmetic is proposed for parallel optical computing based on new joint spatial encodings. This reduces hardware requirements and improves throughput by reducing the space-bandwidth produce needed. The high-radix signed-digit arithmetic operations are based on classifying the neighboring input digit pairs into various groups to reduce the computation rules. A new joint spatial encoding technique is developed to present both the operands and the computation rules. This technique increases the spatial bandwidth product of the spatial light modulators of the system. An optical implementation of the proposed high-radix signed-digit arithmetic operations is also presented. It is shown that our one-step trinary signed-digit and quaternary signed-digit arithmetic units are much simpler and better than all previously reported high-radix signed-digit techniques.

  16. Digital spot mammography using an add-on upright unit: diagnostic application in daily practice

    International Nuclear Information System (INIS)

    Mesurolle, Benoit; Mignon, Francois; Ariche-Cohen, Michele; Kao, Ellen; Gagnon, Jean H.; Goumot, Pierre-Alain

    2004-01-01

    Introduction: To present the use of digital spot mammography (DSM) in a diagnostic practice. Methods and patients: Digital spot images of 779 women requiring a spot compression or a spot magnification view were collected. The digital images were acquired on a digital spot upright unit using a 61 mmx61 mm field of view. Lesions reported included masses, calcifications, and areas of distortions. Results: 1065 lesions required additional views with DSM. Lesions reported included masses (n=113), masses and microcalcifications (n=53), spiculated masses (n=34), architectural distortions (n=16), and microcalcifications (n=849). DSMs were considered to be adequate in 97.7% of patients. Unsatisfactory exams resulted from difficulties encountered in targeting the area of interest at the beginning of our experience. Conclusion: DSM, most commonly used to perform interventional procedures, can also be used in a diagnostic practice taking advantage of post-processing of images not available with conventional spot compression and magnification

  17. A Radix-10 Digit-Recurrence Division Unit: Algorithm and Architecture

    DEFF Research Database (Denmark)

    Lang, Tomas; Nannarelli, Alberto

    2007-01-01

    In this work, we present a radix-10 division unit that is based on the digit-recurrence algorithm. The previous decimal division designs do not include recent developments in the theory and practice of this type of algorithm, which were developed for radix-2^k dividers. In addition to the adaptat...... dynamic range of significant) and it has a shorter latency than a radix-10 unit based on the Newton-Raphson approximation....

  18. The use of the Statscan digital X-ray unit in paediatric polytrauma

    Energy Technology Data Exchange (ETDEWEB)

    Pitcher, Richard D. [University of Cape Town, Division of Paediatric Radiology, Red Cross War Memorial Children' s Hospital, School of Child and Adolescent Health, Cape Town (South Africa); Wilde, Jim C.H. [University of Cape Town, Division of Paediatric Surgery, Red Cross War Memorial Children' s Hospital, School of Child and Adolescent Health, Cape Town (South Africa); University of Amsterdam, Paediatric Surgical Centre of Amsterdam, Emma Children' s Hospital, Academic Medical Centre, Amsterdam (Netherlands); Douglas, Tania S. [University of Cape Town, MRC/UCT Medical Imaging Research Unit, Department of Human Biology, Cape Town (South Africa); As, Arjan Bastiaan van [University of Cape Town, Division of Paediatric Surgery, Red Cross War Memorial Children' s Hospital, School of Child and Adolescent Health, Cape Town (South Africa)

    2009-05-15

    We present a 3-year review of clinical paediatric experience with the statscan (Lodox Systems, Johannesburg, South Africa), a low-dose, digital, whole-body, slit-scanning X-ray machine. While focusing on the role of the unit in paediatric polytrauma, insight into its applications in other paediatric settings is provided. (orig.)

  19. The use of the Statscan digital X-ray unit in paediatric polytrauma

    International Nuclear Information System (INIS)

    Pitcher, Richard D.; Wilde, Jim C.H.; Douglas, Tania S.; As, Arjan Bastiaan van

    2009-01-01

    We present a 3-year review of clinical paediatric experience with the statscan (Lodox Systems, Johannesburg, South Africa), a low-dose, digital, whole-body, slit-scanning X-ray machine. While focusing on the role of the unit in paediatric polytrauma, insight into its applications in other paediatric settings is provided. (orig.)

  20. Implementation of a digital feedwater control system at Dresden Nuclear Power Plant, Units 2 and 3: Final report

    International Nuclear Information System (INIS)

    Zapotocky, A.; Popovic, J.R.; Fournier, R.D.

    1988-12-01

    This report describes the Digital Feedwater Control System Implementation at the Dresden 2 or 3 Units of the BWR Nuclear Power Plant owned by the Commonwealth Edison Company. The digital system has been operational in Unit 3 since August 1986, and in Unit 2 since April 1987. The Bailey Control's Network 90 based digital control system replaced the obsolete GE/MAC 5000 analog control system in the reactor feedwater control loop as a ''like-for-like'' replacement. Operational experience from the Digital Feedwater Control installations has been good and the system demonstrated better performance than the old analog systems. 14 refs., 15 figs., 17 tabs

  1. Use of border information in the classification of mammographic masses

    International Nuclear Information System (INIS)

    Varela, C; Timp, S; Karssemeijer, N

    2006-01-01

    We are developing a new method to characterize the margin of a mammographic mass lesion to improve the classification of benign and malignant masses. Towards this goal, we designed features that measure the degree of sharpness and microlobulation of mass margins. We calculated these features in a border region of the mass defined as a thin band along the mass contour. The importance of these features in the classification of benign and malignant masses was studied in relation to existing features used for mammographic mass detection. Features were divided into three groups, each representing a different mass segment: the interior region of a mass, the border and the outer area. The interior and the outer area of a mass were characterized using contrast and spiculation measures. Classification was done in two steps. First, features representing each of the three mass segments were merged into a neural network classifier resulting in a single regional classification score for each segment. Secondly, a classifier combined the three single scores into a final output to discriminate between benign and malignant lesions. We compared the classification performance of each regional classifier and the combined classifier on a data set of 1076 biopsy proved masses (590 malignant and 486 benign) from 481 women included in the Digital Database for Screening Mammography. Receiver operating characteristic (ROC) analysis was used to evaluate the accuracy of the classifiers. The area under the ROC curve (A z ) was 0.69 for the interior mass segment, 0.76 for the border segment and 0.75 for the outer mass segment. The performance of the combined classifier was 0.81 for image-based and 0.83 for case-based evaluation. These results show that the combination of information from different mass segments is an effective approach for computer-aided characterization of mammographic masses. An advantage of this approach is that it allows the assessment of the contribution of regions rather

  2. 78 FR 47011 - Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants

    Science.gov (United States)

    2013-08-02

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software... revised regulatory guide (RG), revision 1 of RG 1.171, ``Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants.'' This RG endorses American National Standards...

  3. 77 FR 50722 - Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants

    Science.gov (United States)

    2012-08-22

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software...) is issuing for public comment draft regulatory guide (DG), DG-1208, ``Software Unit Testing for Digital Computer Software used in Safety Systems of Nuclear Power Plants.'' The DG-1208 is proposed...

  4. Posterior breast cancer: Mammographic and ultrasonographic features

    Directory of Open Access Journals (Sweden)

    Janković Ana

    2013-01-01

    Full Text Available Background/Aim. Posterior breast cancers are located in the prepectoral region of the breast. Owing to this distinctive anatomical localization, physical examination and mammographic or ultrasonographic evaluation can be difficult. The purpose of the study was to assess possibilities of diagnostic mammography and breast ultrasonography in detection and differentiation of posterior breast cancers. Methods. The study included 40 women with palpable, histopathological confirmed posterior breast cancer. Mammographic and ultrasonographic features were defined according to Breast Imaging Reporting and Data System (BI-RADS lexicon. Results. Based on standard two-view mammography 87.5%, of the cases were classified as BI-RADS 4 and 5 categories, while after additional mammographic views all the cases were defined as BIRADS 4 and 5 categories. Among 96 mammographic descriptors, the most frequent were: spiculated mass (24.0%, architectural distortion (16.7%, clustered microcalcifications (12.6% and focal asymmetric density (12.6%. The differentiation of the spiculated mass was significantly associated with the possibility to visualize the lesion at two-view mammography (p = 0.009, without the association with lesion diameter (p = 0.083 or histopathological type (p = 0.055. Mammographic signs of invasive lobular carcinoma were significantly different from other histopathological types (architectural distortion, p = 0.003; focal asymmetric density, p = 0.019; association of four or five subtle signs of malignancy, p = 0.006. All cancers were detectable by ultrasonography. Mass lesions were found in 82.0% of the cases. Among 153 ultrasonographic descriptors, the most frequent were: irregular mass (15.7%, lobulated mass (7.2%, abnormal color Doppler signals (20.3%, posterior acoustic attenuation (18.3%. Ultrasonographic BI-RADS 4 and 5 categories were defined in 72.5% of the cases, without a significant difference among various histopathological types (p = 0

  5. [Digital luminescence radiography. A new method of study in thoracic diagnosis at the intensive care unit].

    Science.gov (United States)

    Witte, G; Pothmann, W; Bause, H; Nicolas, V; Schulte am Esch, J; Bücheler, E

    1989-02-01

    The digital luminescence-radiography (DLR) technique relies on a complete digitalization of the X-ray image. Luminescence crystals on the imaging plate serve as an energy reservoir following their exposure to ionized radiation from any conventional X-ray source. A Helium-Neon laser stimulates the electrons in their high energy bands and therefore will be dropped back emitting luminescence. This luminescence is digitized by the DLR-System thus delivering a complete digital image to the image processor for subsequent processing and evaluation. The processed digital image is then recorded on a conventional film or a monitor screen. More than 3000 chest examinations using DLR have been performed on intensive care unit (ICU) patients at the University Hospital Eppendorf following the first eleven months since the clinical introduction of this new technique. The positive aspects of DLR such as high-contrast resolution and optimal reproducibility were clinically evaluated under ICU conditions. It was shown that DLR greatly improves the quality of the chest X-rays of all ICU patients and offers the following advantages: reproducibility, lateral chest projection, no insufficient exposure, reduction of exposure dose, electronical post-processing and storage, quality preserving digital storage and copying.

  6. Training for integrated digital I and C system of Tomari unit 3

    International Nuclear Information System (INIS)

    Tutiya, Akiyoshi; Sanbe, Takayuki; Hayashi, Hiroshi

    2009-01-01

    In Tomari nuclear power station Unit No.3, integrated digital I and C facilities was applied for each control unit including safety protection system overall and which connect them by bus (a network), and perform data communications for the first time as a Japanese PWR power station. For the continuation of safe and stable operation of Tomari nuclear power station Unit No.3 which is our greatest power supply, it is important to perform appropriate maintenance jobs about integrated digital I and C System at the time of normal operation, periodical inspection and trouble outbreak. For the assured accomplishment of these work by maintenance personnel, we clarified goal of necessary knowledge and skills and examined training facilities and curriculums. (author)

  7. Cone-beam volume CT mammographic imaging: feasibility study

    Science.gov (United States)

    Chen, Biao; Ning, Ruola

    2001-06-01

    X-ray projection mammography, using a film/screen combination or digital techniques, has proven to be the most effective imaging modality for early detection of breast cancer currently available. However, the inherent superimposition of structures makes small carcinoma (a few millimeters in size) difficult to detect in the occultation case or in dense breasts, resulting in a high false positive biopsy rate. The cone-beam x-ray projection based volume imaging using flat panel detectors (FPDs) makes it possible to obtain three-dimensional breast images. This may benefit diagnosis of the structure and pattern of the lesion while eliminating hard compression of the breast. This paper presents a novel cone-beam volume CT mammographic imaging protocol based on the above techniques. Through computer simulation, the key issues of the system and imaging techniques, including the x-ray imaging geometry and corresponding reconstruction algorithms, x-ray characteristics of breast tissues, x-ray setting techniques, the absorbed dose estimation and the quantitative effect of x-ray scattering on image quality, are addressed. The preliminary simulation results support the proposed cone-beam volume CT mammographic imaging modality in respect to feasibility and practicability for mammography. The absorbed dose level is comparable to that of current two-view mammography and would not be a prominent problem for this imaging protocol. Compared to traditional mammography, the proposed imaging protocol with isotropic spatial resolution will potentially provide significantly better low contrast detectability of breast tumors and more accurate location of breast lesions.

  8. A comprehensive tool for measuring mammographic density changes over time.

    Science.gov (United States)

    Eriksson, Mikael; Li, Jingmei; Leifland, Karin; Czene, Kamila; Hall, Per

    2018-06-01

    Mammographic density is a marker of breast cancer risk and diagnostics accuracy. Density change over time is a strong proxy for response to endocrine treatment and potentially a stronger predictor of breast cancer incidence. We developed STRATUS to analyse digital and analogue images and enable automated measurements of density changes over time. Raw and processed images from the same mammogram were randomly sampled from 41,353 healthy women. Measurements from raw images (using FDA approved software iCAD) were used as templates for STRATUS to measure density on processed images through machine learning. A similar two-step design was used to train density measures in analogue images. Relative risks of breast cancer were estimated in three unique datasets. An alignment protocol was developed using images from 11,409 women to reduce non-biological variability in density change. The protocol was evaluated in 55,073 women having two regular mammography screens. Differences and variances in densities were compared before and after image alignment. The average relative risk of breast cancer in the three datasets was 1.6 [95% confidence interval (CI) 1.3-1.8] per standard deviation of percent mammographic density. The discrimination was AUC 0.62 (CI 0.60-0.64). The type of image did not significantly influence the risk associations. Alignment decreased the non-biological variability in density change and re-estimated the yearly overall percent density decrease from 1.5 to 0.9%, p density measures was not influenced by mammogram type. The alignment protocol reduced the non-biological variability between images over time. STRATUS has the potential to become a useful tool for epidemiological studies and clinical follow-up.

  9. Digitization

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    what a concept of digital media might add to the understanding of processes of mediatization and what the concept of mediatization might add to the understanding of digital media. It is argued that digital media open an array of new trajectories in human communication, trajectories which were...

  10. A uniform system for mammographic reporting BI-RADS

    International Nuclear Information System (INIS)

    Masroor, I.; Ahmad, M. N.; Sheikh, M. Y.

    2001-01-01

    Breast image reporting and data system (BI-RADS) is a new system of categorizing and reporting mammographs and mammographic findings recommended by American College of Radiology. The importance of BI-RADS and final assessment categories are discussed. The purpose is to introduce the above-mentioned mammographic reporting system so that it becomes a standard terminology among the medical personnel, involved in the diagnosis and management of breast diseases. (author)

  11. Monitoring the consistency of the dynalyser output via digital display unit and calculated practical peak voltage

    International Nuclear Information System (INIS)

    Wan Hazlinda Ismail; Muhammad Jamal Mohd Isa; Abdul Aziz Mohd Ramli; Shahrul Azlan Azizan

    2010-01-01

    This study was carried out to ensure the adequacy and accuracy of the Dynalyser Digital Display unit for measuring the true kVp from the invasive kVp meter unit during calibration of non-invasive kVp meters. An invasive high voltage divider (dynalyser) coupled to the x-ray system measures the true kilo voltage supplied to the x-ray tube. The kVp output measured was displayed via its digital display unit while its waveform was acquired using a calibrated oscilloscope. The waveform was used to calculate the Practical Peak Voltage (PPV) using the International Standard method adapted from IEC 61676 and treated as the true kVp value. The kVp output was measured at 9 points ranging between 40 kV-120 kV with interval steps of 10 kV and monitored every day. The test result was evaluated for variation of output, intrinsic error and limit of variation in compliance with the IEC standard. Results showed that kVp output measured by the display unit everyday is consistent with variations of not more than ±0.45 kV, intrinsic error of not more than ±0.009 kV and limits of variation of less than 1% which comply with the IEC standard requirement. The kVp output via digital display unit has a total uncertainty of not more than 2.8 kV (k=2) while the PPV output via oscilloscope has total uncertainty of not more than 0.75 kV (k=2). As a conclusion, the dynalyser digital display unit complies with standard requirement and can be used to measure the true kVp output during the calibration of non-invasive kVp meters. (author)

  12. Association of mammographic image feature change and an increasing risk trend of developing breast cancer: an assessment

    Science.gov (United States)

    Tan, Maxine; Leader, Joseph K.; Liu, Hong; Zheng, Bin

    2015-03-01

    We recently investigated a new mammographic image feature based risk factor to predict near-term breast cancer risk after a woman has a negative mammographic screening. We hypothesized that unlike the conventional epidemiology-based long-term (or lifetime) risk factors, the mammographic image feature based risk factor value will increase as the time lag between the negative and positive mammography screening decreases. The purpose of this study is to test this hypothesis. From a large and diverse full-field digital mammography (FFDM) image database with 1278 cases, we collected all available sequential FFDM examinations for each case including the "current" and 1 to 3 most recently "prior" examinations. All "prior" examinations were interpreted negative, and "current" ones were either malignant or recalled negative/benign. We computed 92 global mammographic texture and density based features, and included three clinical risk factors (woman's age, family history and subjective breast density BIRADS ratings). On this initial feature set, we applied a fast and accurate Sequential Forward Floating Selection (SFFS) feature selection algorithm to reduce feature dimensionality. The features computed on both mammographic views were individually/ separately trained using two artificial neural network (ANN) classifiers. The classification scores of the two ANNs were then merged with a sequential ANN. The results show that the maximum adjusted odds ratios were 5.59, 7.98, and 15.77 for using the 3rd, 2nd, and 1st "prior" FFDM examinations, respectively, which demonstrates a higher association of mammographic image feature change and an increasing risk trend of developing breast cancer in the near-term after a negative screening.

  13. Analysis of mammographic findings of breast cancer

    International Nuclear Information System (INIS)

    Park, Hyun Joo; Han, Heon; Yang, Dal Mo; Chung, Hyo Sun; Kim, Jee Eun; Kim, Young Chae

    1995-01-01

    This study is to describe authors' experience on mammographic findings of breast cancer and to know if there is difference between 35 years of age or younger and older groups. Mammograms of 72 patients with breast cancer detected from January, 1991 to December, 1993 were retrospectively analysed. Mammographic findings were classified into mass only, mass with microcalcifications, microcalcifications only and others. Marginal characteristics of mass were classified into spiculated, poorly marginated and well marginated. Shape of microcalcifications were classified into casting, granular and mixed types. These findings were compared between 35 years of age or younger and older groups. Mammogram showed mass only in 33 patients (46%), mass with microcalcifications in 26 patients (36%), microcalcifications only in seven (10%) and other findings in six (8%). Other findings were architectural distortion, asymmetric high density and incidental breast carcinoma from paraffinoma in one patient respectively, and dense breast in three patients. The margins of the breast mass were spiculated in ten (17%). poorly marginated in 30 (51%), well-marginated in 19 (32%). Shape of microcalcifications were casting type in 13 (40%). granular in 14 (42%) and mixed in six (18%) cases. 3 patients had dense breast with which mammography did not demonstrate the lesion. 3 patients without mammographically demonstrable lesions due to dense breasts were under 35 years in age, and there was statistically significant difference between the two groups (ρ -value < 0.05). Microcalcifications only was more common findings in 35 years of age or younger. The most important mammographic findings of breast cancer were mass and microcalcifications. Architectural distortion and asymmetric high density were additional findings. In 35 years of age or younger, microcalcifications only was an important finding because mass lesions are frequently masked by dense breast. Thus other imaging modalities, such as

  14. Ultrasonographic Findings of Mammographic Architectural Distortion

    International Nuclear Information System (INIS)

    Ma, Jeong Hyun; Kang, Bong Joo; Cha, Eun Suk; Hwangbo, Seol; Kim, Hyeon Sook; Park, Chang Suk; Kim, Sung Hun; Choi, Jae Jeong; Chung, Yong An

    2008-01-01

    To review the sonographic findings of various diseases showing architectural distortion depicted under mammography. We collected and reviewed architectural distortions observed under mammography at our health institution between 1 March 2004, and 28 February 2007. We collected 23 cases of sonographically-detected mammographic architectural distortions that confirmed lesions after surgical resection. The sonographic findings of mammographic architectural distortion were analyzed by use of the BI-RADS lexicon for shape, margin, lesion boundary, echo pattern, posterior acoustic feature and orientation. There were variable diseases that showed architectural distortion depicted under mammography. Fibrocystic disease was the most common presentation (n = 6), followed by adenosis (n = 2), stromal fibrosis (n = 2), radial scar (n = 3), usual ductal hyperplasia (n = 1), atypical ductal hyperplasia (n = 1) and mild fibrosis with microcalcification (n = 1). Malignant lesions such as ductal carcinoma in situ (DCIS) (n = 2), lobular carcinoma in situ (LCIS) (n = 2), invasive ductal carcinoma (n = 2) and invasive lobular carcinoma (n = 1) were observed. As observed by sonography, shape was divided as irregular (n = 22) and round (n = 1). Margin was divided as circumscribed (n = 1), indistinct (n = 7), angular (n = 1), microlobulated (n = 1) and sipculated (n = 13). Lesion boundary was divided as abrupt interface (n = 11) and echogenic halo (n = 12). Echo pattern was divided as hypoechoic (n = 20), anechoic (n = 1), hyperechoic (n = 1) and isoechoic (n = 1). Posterior acoustic feature was divided as posterior acoustic feature (n = 7), posterior acoustic shadow (n = 15) and complex posterior acoustic feature (n = 1). Orientation was divided as parallel (n = 12) and not parallel (n = 11). There were no differential sonographic findings between benign and malignant lesions. This study presented various sonographic findings of mammographic architectural distortion and that it is

  15. Decision trees and integrated features for computer aided mammographic screening

    Energy Technology Data Exchange (ETDEWEB)

    Kegelmeyer, W.P. Jr.; Groshong, B.; Allmen, M.; Woods, K.

    1997-02-01

    Breast cancer is a serious problem, which in the United States causes 43,000 deaths a year, eventually striking 1 in 9 women. Early detection is the only effective countermeasure, and mass mammography screening is the only reliable means for early detection. Mass screening has many shortcomings which could be addressed by a computer-aided mammographic screening system. Accordingly, we have applied the pattern recognition methods developed in earlier investigations of speculated lesions in mammograms to the detection of microcalcifications and circumscribed masses, generating new, more rigorous and uniform methods for the detection of both those signs. We have also improved the pattern recognition methods themselves, through the development of a new approach to combinations of multiple classifiers.

  16. Digital scrapbooking as a standard of care in neonatal intensive care units: initial experience.

    Science.gov (United States)

    Subhani, Muhammad T; Kanwal, Ifrah

    2012-01-01

    In this article, we describe a digital photo scrapbooking project as a standard of care for the parents of infants admitted in a neonatal intensive care unit (NICU). Photographs were taken from birth until discharge or expiry at special moments during the infant's hospitalization and used to create a digital scrapbook with daily notes by the parents. The scrapbook and original photos were provided on a CD at discharge or at expiry. Parents and their families unanimously appreciated the photos and the opportunity to record their thoughts, and considered the CDs as a lifetime treasure. Digital photo journaling could be implemented as a standard of care at other institutions with a commitment from the nursing and ancillary staff of the NICU and labor and delivery department, with possible support from volunteers.

  17. THE MAMMOGRAPHIC CALCIFICATIONS IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    Tang Ruiying; Liu Jingxian; Gaowen

    1998-01-01

    Objective: This study was performed to exam the relativeship between mammographic calcifications and breast cancer. Methods: All of the 184 patients with breast diseases underwent mammography before either an open biopsy or a mastectomy. The presence,morphology, and distribution of calcifications visualized on mammograms for breast cancer were compared with the controls who remained cancer free. Statistical comparisons were made by using the x2 test. Results:Of the 184 patients with breast diaeases, 93 malignant and 91 benign lesions were histologically confirmed.Calcifications were visualized on mammograms in 60(64%) of 93 breast cancers and 26 (28%) of 91 non breast cancers. The estimated odds ratio (OR) of breast cancer was 4.5 in women with calcifications seen on mammograms, compared with those having none (P<0.01). Of the 60 breast carcinomas having mammographic calcifications, 28 (47%) were infiltrating ductal carcinomas.There were only 8 (24%) cases with infiltrating ductal cancers in the group of without calcifications seen on the mammograms (P<0.05). Conclusion: Our finding suggests that mammographic calcification appears to be a risk factor for breast cancer. The granular and linear cast type calcification provide clues to the presence of breast cancer, especially when the carcinomas without associated masses were seen on mammograms.

  18. Bilateral breast cancer : mammographic and clinical findings

    International Nuclear Information System (INIS)

    Kim, Eun Kyung; Oh, Ki Keun; Jun, Hwang Yoon; Lee, Byung Chan; Lee, Kyong Sik; Lee, Yong Hee

    1997-01-01

    To evaluate the mammographic and clinical features of bilateral breast cancer. We retrospectively reviewed clinical records(n=23) and mammograms (n=15) of 23 patients with bilateral breast cancer. Patients' age, location of the tumor and pathologic staging were determined from clinical records. Mammographic features were classified as spiculated mass, nonspiculated mass, mass with microcalcification, microcalcification only, asymmetric density, and normal. Of the 23 cases of bilateral breast cancer, 8(34.8%) were synchronous and 15(65.2%) were metachronous. Age at diagnosis of cancer in the first breast was between 27 and 59(mean 43) years ; there was no statistically significant difference in mean age between patients with synchronous and metachronous cancer. The mean interval between the diagnosis of each lesion of the metachronous pairs was 9.1 years. In 11 of 23 cases(48%), tumors were locaated in the same quadrant, and in the other 12 cases(52%), they were in different quadrant. At mammography, five of 15 metachronous cancers(33%) were similar in appearance and 10 pairs(67%) were different. In 4 of 23 cases(17%), cancer in the first breast was at stage 0 and stage 1, and in 13 of 23(57%), cancer in the second breast was at this same stage. In bilateral breast cancer, the two breasts frequently show different mammographic features. Cancer of the second breast was at an early stage; this suggest that regular examination and mammography are important and can allow early detection of contralateral breast cancer

  19. Computer-aided diagnosis of mammographic microcalcification clusters

    International Nuclear Information System (INIS)

    Kallergi, Maria

    2004-01-01

    Computer-aided diagnosis techniques in medical imaging are developed for the automated differentiation between benign and malignant lesions and go beyond computer-aided detection by providing cancer likelihood for a detected lesion given image and/or patient characteristics. The goal of this study was the development and evaluation of a computer-aided detection and diagnosis algorithm for mammographic calcification clusters. The emphasis was on the diagnostic component, although the algorithm included automated detection, segmentation, and classification steps based on wavelet filters and artificial neural networks. Classification features were selected primarily from descriptors of the morphology of the individual calcifications and the distribution of the cluster. Thirteen such descriptors were selected and, combined with patient's age, were given as inputs to the network. The features were ranked and evaluated for the classification of 100 high-resolution, digitized mammograms containing biopsy-proven, benign and malignant calcification clusters. The classification performance of the algorithm reached a 100% sensitivity for a specificity of 85% (receiver operating characteristic area index A z =0.98±0.01). Tests of the algorithm under various conditions showed that the selected features were robust morphological and distributional descriptors, relatively insensitive to segmentation and detection errors such as false positive signals. The algorithm could exceed the performance of a similar visual analysis system that was used as basis for development and, combined with a simple image standardization process, could be applied to images from different imaging systems and film digitizers with similar sensitivity and specificity rates

  20. The instrument control unit of SPICA SAFARI: a macro-unit to host all the digital control functionalities of the spectrometer

    Science.gov (United States)

    Di Giorgio, Anna Maria; Biondi, David; Saggin, Bortolino; Shatalina, Irina; Viterbini, Maurizio; Giusi, Giovanni; Liu, Scige J.; Cerulli-Irelli, Paquale; Van Loon, Dennis; Cara, Christophe

    2012-09-01

    We present the preliminary design of the Instrument Control Unit (ICU) of the SpicA FAR infrared Instrument (SAFARI), an imaging Fourier Transform Spectrometer (FTS) designed to give continuous wavelength coverage in both photometric and spectroscopic modes from around 34 to 210 µm. Due to the stringent requirements in terms of mass and volume, the overall SAFARI warm electronics will be composed by only two main units: Detector Control Unit and ICU. ICU is therefore a macro-unit incorporating the four digital sub-units dedicated to the control of the overall instrument functionalities: the Cooler Control Unit, the Mechanism Control Unit, the Digital processing Unit and the Power Supply Unit. Both the mechanical solution adopted to host the four sub-units and the internal electrical architecture are presented as well as the adopted redundancy approach.

  1. Textural Classification of Mammographic Parenchymal Patterns with the SONNET Selforganizing Neural Network

    Directory of Open Access Journals (Sweden)

    Daniel Howard

    2008-01-01

    Full Text Available In nationwide mammography screening, thousands of mammography examinations must be processed. Each consists of two standard views of each breast, and each mammogram must be visually examined by an experienced radiologist to assess it for any anomalies. The ability to detect an anomaly in mammographic texture is important to successful outcomes in mammography screening and, in this study, a large number of mammograms were digitized with a highly accurate scanner; and textural features were derived from the mammograms as input data to a SONNET selforganizing neural network. The paper discusses how SONNET was used to produce a taxonomic organization of the mammography archive in an unsupervised manner. This process is subject to certain choices of SONNET parameters, in these numerical experiments using the craniocaudal view, and typically produced O(10, for example, 39 mammogram classes, by analysis of features from O(103 mammogram images. The mammogram taxonomy captured typical subtleties to discriminate mammograms, and it is submitted that this may be exploited to aid the detection of mammographic anomalies, for example, by acting as a preprocessing stage to simplify the task for a computational detection scheme, or by ordering mammography examinations by mammogram taxonomic class prior to screening in order to encourage more successful visual examination during screening. The resulting taxonomy may help train screening radiologists and conceivably help to settle legal cases concerning a mammography screening examination because the taxonomy can reveal the frequency of mammographic patterns in a population.

  2. Investigation of the performance of digital mammographic X-Ray equipment: Determination of noise equivalent quanta (NEQQC) and detective quantum efficiency (DQEQC) compared with the automated analysis of CDMAM test images with CDCOM and CDIC programs

    International Nuclear Information System (INIS)

    Loos, C.; Buhr, H.; Blendl, C.

    2013-01-01

    Purpose: The purpose of this study was to determine the values for noise equivalent quanta, detective quantum efficiency, modulation transfer function, noise power spectrum, and the values for the parameters for automated CDMAM test phantom analyses required to achieve satisfactory quality of digital mammograms. Materials and Methods: During the course of tests according to PAS 1054 (8 CR and 12 DR systems), test images were made with a test phantom insertion plate containing two lead edges in nearly horizontal and vertical directions. Only original data were processed with a program that was developed at the Cologne University of Applied Sciences (FH-Koeln). All equipment systems complied with the requirements regarding visual recognition of gold-plated mammo detail test objects. CDMAM test images were also evaluated using the CDIC (CUAS) and CDCOM (EUREF) programs. Results: CDMAM test images show comparable values for the parameters, precision, sensitivity and specificity. DR systems require about half the dose used for CR systems for similar results. The NEQ values achieved with the dose used for the CDMAM test images show larger scatter ranges. The MTF of the different equipment system types differ significantly from each other. Conclusion: Visual evaluation of CDMAM test images can be replaced by automated evaluation. Limiting values were determined for each parameter. Automated evaluation of CDMAM test phantom images should be used to determine the physical parameter NEQ QC . This method is much more sensitive to noise and sharpness influences and has a higher validity than diagnostic methods. Automated evaluation objectivizes testing. (orig.)

  3. Mammographic breast density patterns among a group of women in ...

    African Journals Online (AJOL)

    Introduction: Mammographic breast density is a measure of parenchymal breast patterns on film and in part a marker of cumulative exposure to oestrogen. The risk of breast cancer for women with increased density is up to six fold more than in women with less dense tissues. The pattern of mammographic breast density ...

  4. Changes in mammographic density and breast cancer risk

    NARCIS (Netherlands)

    Lokate, A.J.M.

    2012-01-01

    Breast cancer is the most frequently occurring cancer among women worldwide. One of the most important risk factors for breast cancer is high mammographic density. Mammographic density represents the amount of fibroglandular tissue relative to the fat tissue in the breast. Women with >75% of their

  5. The combined effect of mammographic texture and density on breast cancer risk: a cohort study.

    Science.gov (United States)

    Wanders, Johanna O P; van Gils, Carla H; Karssemeijer, Nico; Holland, Katharina; Kallenberg, Michiel; Peeters, Petra H M; Nielsen, Mads; Lillholm, Martin

    2018-05-02

    Texture patterns have been shown to improve breast cancer risk segregation in addition to area-based mammographic density. The additional value of texture pattern scores on top of volumetric mammographic density measures in a large screening cohort has never been studied. Volumetric mammographic density and texture pattern scores were assessed automatically for the first available digital mammography (DM) screening examination of 51,400 women (50-75 years of age) participating in the Dutch biennial breast cancer screening program between 2003 and 2011. The texture assessment method was developed in a previous study and validated in the current study. Breast cancer information was obtained from the screening registration system and through linkage with the Netherlands Cancer Registry. All screen-detected breast cancers diagnosed at the first available digital screening examination were excluded. During a median follow-up period of 4.2 (interquartile range (IQR) 2.0-6.2) years, 301 women were diagnosed with breast cancer. The associations between texture pattern scores, volumetric breast density measures and breast cancer risk were determined using Cox proportional hazard analyses. Discriminatory performance was assessed using c-indices. The median age of the women at the time of the first available digital mammography examination was 56 years (IQR 51-63). Texture pattern scores were positively associated with breast cancer risk (hazard ratio (HR) 3.16 (95% CI 2.16-4.62) (p value for trend <0.001), for quartile (Q) 4 compared to Q1). The c-index of texture was 0.61 (95% CI 0.57-0.64). Dense volume and percentage dense volume showed positive associations with breast cancer risk (HR 1.85 (95% CI 1.32-2.59) (p value for trend <0.001) and HR 2.17 (95% CI 1.51-3.12) (p value for trend <0.001), respectively, for Q4 compared to Q1). When adding texture measures to models with dense volume or percentage dense volume, c-indices increased from 0.56 (95% CI 0.53-0.59) to 0

  6. Mammographic texture resemblance generalizes as an independent risk factor for breast cancer

    DEFF Research Database (Denmark)

    Nielsen, Mads; Vachon, Celine M.; Scott, Christopher G.

    2014-01-01

    INTRODUCTION:Breast density has been established as a major risk factor for breast cancer. We have previously demonstrated that mammographic texture resemblance (MTR), recognizing the local texture patterns of the mammogram, is also a risk factor for breast cancer, independent of percent breast...... density. We examine if these findings generalize to another population.METHODS:Texture patterns were recorded in digitalized pre-diagnosis (3.7years) film mammograms of a nested case-control study within the Dutch screening program (S1) comprising of 245 breast cancers and 250 matched controls...

  7. EnviroAtlas - Percent Land Cover with Potentially Restorable Wetlands on Agricultural Land per 12-Digit HUC - Contiguous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the percent land cover with potentially restorable wetlands on agricultural land for each 12-digit Hydrologic Unit (HUC) watershed in...

  8. EnviroAtlas - Annual average potential wind energy resource by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the annual average potential wind energy resource in kilowatt hours per square kilometer per day for each 12-digit Hydrologic Unit...

  9. Mammographic compression – A need for mechanical standardization

    Energy Technology Data Exchange (ETDEWEB)

    Branderhorst, Woutjan, E-mail: w.branderhorst@amc.nl [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Sigmascreening B.V., Meibergdreef 45, 1105 BA Amsterdam (Netherlands); Groot, Jerry E. de, E-mail: jerry.degroot@sigmascreening.com [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Highnam, Ralph, E-mail: ralph.highnam@volparasolutions.com [Volpara Solutions Limited, P.O. Box 24404, Manners St Central, Wellington 6142 (New Zealand); Chan, Ariane, E-mail: ariane.chan@volparasolutions.com [Volpara Solutions Limited, P.O. Box 24404, Manners St Central, Wellington 6142 (New Zealand); Böhm-Vélez, Marcela, E-mail: marcelabvelez@gmail.com [Weinstein Imaging Associates, 5850 Centre Avenue, Pittsburgh, PA 15206 (United States); Broeders, Mireille J.M., E-mail: mireille.broeders@radboudumc.nl [Radboud University Medical Center, Department for Health Evidence, P.O. Box 9101, 6500 HB Nijmegen (Netherlands); LRCB Dutch Reference Center for Screening, P.O. Box 6873, 6503 GJ Nijmegen (Netherlands); Heeten, Gerard J. den, E-mail: g.denheeten@lrcb.nl [Academic Medical Center, Department of Radiology, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); LRCB Dutch Reference Center for Screening, P.O. Box 6873, 6503 GJ Nijmegen (Netherlands); Grimbergen, Cornelis A., E-mail: c.a.grimbergen@amc.uva.nl [Academic Medical Center, Department of Biomedical Engineering & Physics, P.O. Box 22660, 1100 DD Amsterdam (Netherlands); Sigmascreening B.V., Meibergdreef 45, 1105 BA Amsterdam (Netherlands)

    2015-04-15

    Highlights: •We studied mechanical breast compression practice in two different clinical sites. •We visualized the distributions of not only the applied force but also the pressure. •The applied pressure was highly variable, both within and between the data sets. •The average applied pressure and the variation were higher for smaller breasts. •A proposal for improved individualization, by standardizing pressure, is discussed. -- Abstract: Background: A lack of consistent guidelines regarding mammographic compression has led to wide variation in its technical execution. Breast compression is accomplished by means of a compression paddle, resulting in a certain contact area between the paddle and the breast. This procedure is associated with varying levels of discomfort or pain. On current mammography systems, the only mechanical parameter available in estimating the degree of compression is the physical entity of force (daN). Recently, researchers have suggested that pressure (kPa), resulting from a specific force divided by contact area on a breast, might be a more appropriate parameter for standardization. Software has now become available which enables device-independent cross-comparisons of key mammographic metrics, such as applied compression pressure (force divided by contact area), breast density and radiation dose, between patient populations. Purpose: To compare the current compression practice in mammography between different imaging sites in the Netherlands and the United States from a mechanical point of view, and to investigate whether the compression protocols in these countries can be improved by standardization of pressure (kPa) as an objective mechanical parameter. Materials and methods: We retrospectively studied the available parameters of a set of 37,518 mammographic compressions (9188 women) from the Dutch national breast cancer screening programme (NL data set) and of another set of 7171 compressions (1851 women) from a breast imaging

  10. DIGITAL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. Automated effect-specific mammographic pattern measures

    DEFF Research Database (Denmark)

    Raundahl, Jakob; Loog, Marco; Pettersen, Paola

    2008-01-01

    We investigate the possibility to develop methodologies for assessing effect specific structural changes of the breast tissue using a general statistical machine learning framework. We present an approach of obtaining objective mammographic pattern measures quantifying a specific biological effect......, such as hormone replacement therapy (HRT). We compare results using this approach to using standard density measures. We show that the proposed method can quantify both age related effects and effects caused by HRT. Age effects are significantly detected by our method where standard methodologies fail...

  12. Experimental test of a new technique of background suppression in digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Bisogni, M.G.; Bottari, S.; Ciocci, M.A.; Fantacci, M.E.; Maestro, P.; Malakhov, N.; Marrocchesi, P.S. E-mail: marrocchesi@pi.infn.it; Novelli, M.; Quattrocchi, M.; Pilo, F.; Rosso, V.; Turini, N.; Zucca, S

    2002-02-01

    A multiple-exposure technique in digital mammography has been developed to suppress the physical background in the image due to Compton scattering in the body. A pair of X-ray masks, shaped in a projective geometry and positioned upstream and downstream the patient, are coupled mechanically and moved in four steps along a square pattern in order to irradiate the full area in four consecutive short exposures. A proof-of-principle apparatus is under test with a breast phantom and a standard mammographic X-ray unit. Results are reported.

  13. Experimental test of a new technique of background suppression in digital mammography

    International Nuclear Information System (INIS)

    Bisogni, M.G.; Bottari, S.; Ciocci, M.A.; Fantacci, M.E.; Maestro, P.; Malakhov, N.; Marrocchesi, P.S.; Novelli, M.; Quattrocchi, M.; Pilo, F.; Rosso, V.; Turini, N.; Zucca, S.

    2002-01-01

    A multiple-exposure technique in digital mammography has been developed to suppress the physical background in the image due to Compton scattering in the body. A pair of X-ray masks, shaped in a projective geometry and positioned upstream and downstream the patient, are coupled mechanically and moved in four steps along a square pattern in order to irradiate the full area in four consecutive short exposures. A proof-of-principle apparatus is under test with a breast phantom and a standard mammographic X-ray unit. Results are reported

  14. Actuator digital interface unit (AIU). [control units for space shuttle data system

    Science.gov (United States)

    1973-01-01

    Alternate versions of the actuator interface unit are presented. One alternate is a dual-failure immune configuration which feeds a look-and-switch dual-failure immune hydraulic system. The other alternate is a single-failure immune configuration which feeds a majority voting hydraulic system. Both systems communicate with the data bus through data terminals dedicated to each user subsystem. Both operational control data and configuration control information are processed in and out of the subsystem via the data terminal which yields the actuator interface subsystem, self-managing within its failure immunity capability.

  15. 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.

  16. Classification of mammographic masses using generalized dynamic fuzzy neural networks

    International Nuclear Information System (INIS)

    Lim, Wei Keat; Er, Meng Joo

    2004-01-01

    In this article, computer-aided classification of mammographic masses using generalized dynamic fuzzy neural networks (GDFNN) is presented. The texture parameters, derived from first-order gradient distribution and gray-level co-occurrence matrices, were computed from the regions of interest. A total of 343 images containing 180 benign masses and 163 malignant masses from the Digital Database for Screening Mammography were analyzed. A fast approach of automatically generating fuzzy rules from training samples was implemented to classify tumors. This work is novel in that it alleviates the problem of requiring a designer to examine all the input-output relationships of a training database in order to obtain the most appropriate structure for the classifier in a conventional computer-aided diagnosis. In this approach, not only the connection weights can be adjusted, but also the structure can be self-adaptive during the learning process. By virtue of the automatic generation of the classifier by the GDFNN learning algorithm, the area under the receiver-operating characteristic curve, A z , attains 0.868±0.020, which corresponds to a true-positive fraction of 95.0% at a false positive fraction of 52.8%. The corresponding accuracy is 70.0%, the positive predictive value is 62.0%, and the negative predictive value is 91.4%

  17. Calcified trichinosis of pectoral muscle: mammographic appearance

    International Nuclear Information System (INIS)

    Apesteguia, L.; Murillo, A.; Biurrun, J.; Garcia-Rostan, G.; Reta, A.; Dominguez, F.

    1995-01-01

    By mammographic screening we had detected six asymptomatic women who showed numerious tiny and well-delineated round to ovoid microcalcification superimposed on pectoral shadows, in the oblique medio-lateral (OML) view. Our objective was to achieve a better evaluation of these calcifications and investigate their origin. Magnified mammograms of pectoral muscles were done in the six women. A questionnaire concerning the patients' diets was also administered. Trichinella antibody titres were quantified by sero-agglutination. Microcalcifications within pectoral muscle fibres were demonstrated in all the cases. Five women admitted to having eaten home-made pork products in the past. One of them showed a slightly elevated antibody titre. We confirmed the suspected diagnosis of calcified trichinosis by a surgical biopsy of the pectoral muscle performed on one of the patients. We conclude that chronic calcified trichinosis of the pectoral muscle can be visualised in the OML view of a conventional mammogram. The mammographic appearance of this entity is very characteristic and biopsy would not be required for its diagnosis in the future. (orig.)

  18. Calcified trichinosis of pectoral muscle: mammographic appearance

    Energy Technology Data Exchange (ETDEWEB)

    Apesteguia, L. [Servicio de Radiologia, Hospital Virgen del Camino, Pamplona (Spain); Murillo, A. [Servicio de Radiologia, Hospital Virgen del Camino, Pamplona (Spain); Biurrun, J. [Servicio de Radiologia, Hospital Virgen del Camino, Pamplona (Spain); Garcia-Rostan, G. [Servicio Anatomia Patologica, Hospital Virgen del Camino, Pamplona (Spain); Reta, A. [Servicio de Analisis Clinicos, Hospital Virgen del Camino, Pamplona (Spain); Dominguez, F. [Servicio Cirugia, Hospital Virgen del Camino, Pamplona (Spain)

    1995-12-31

    By mammographic screening we had detected six asymptomatic women who showed numerious tiny and well-delineated round to ovoid microcalcification superimposed on pectoral shadows, in the oblique medio-lateral (OML) view. Our objective was to achieve a better evaluation of these calcifications and investigate their origin. Magnified mammograms of pectoral muscles were done in the six women. A questionnaire concerning the patients` diets was also administered. Trichinella antibody titres were quantified by sero-agglutination. Microcalcifications within pectoral muscle fibres were demonstrated in all the cases. Five women admitted to having eaten home-made pork products in the past. One of them showed a slightly elevated antibody titre. We confirmed the suspected diagnosis of calcified trichinosis by a surgical biopsy of the pectoral muscle performed on one of the patients. We conclude that chronic calcified trichinosis of the pectoral muscle can be visualised in the OML view of a conventional mammogram. The mammographic appearance of this entity is very characteristic and biopsy would not be required for its diagnosis in the future. (orig.)

  19. Ultrasonographic and mammographic findings of gynecomastia

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Kyung; Choi, Gyo Chang; Hong, Hyun Sook; Kim, Young Beom; Lee, Hae Kyung; Kwon, Kui Hyang [Soonchunhyang Univ. College of Medicine, Asan (Korea, Republic of)

    1996-11-01

    The purpose of this study is to evaluate the radiologic features and clinical utility of ultrasonography and mammography in cases of gynecomastia. This study involved 40 men in whom gynecomastia had been pathologically diagnosed by surgical incision. In 21 cases, a retrospective analysis of ultrasonographic and mammographic findings was performed. Causative factors of gynecomastia among the 40 pathologically-proven cases were idiopathic or pubertal in 33 cases, related to male hormone deficiency in three cases and to chronic liver disease in four. Bi-lateral involvement was seen in 14 cases, and unilateral involvement in 26;among unilateral cases, right side was involved in 10 cases, and the left side in 16. Mammographically, a subareolar discoid lesion was present in 12 cases, diffuse increased breast density was seen in five cases and dendritic marginated subareolar lesion without microcalcification in one. Ultrasonographically, a round smooth marginated low echogenic lesion in the subareolar region was seen in five cases, a diffuse hyperechogenic pattern without definite mass in two cases and an ill defined low echogenic lesion in one. The male breast is small, so in cases of gynecomastia, ultrasonography is an effective diagnostic modality. Mamography will, however, be helpful in the detection of microcalcification in cases of gynecomastia seen on sonography.

  20. Tumor location and detectability in mammographic screening

    International Nuclear Information System (INIS)

    Schmitt, E.L.; Threatt, B.

    1982-01-01

    The adequacy of a film mammogram that does not visualize the retromammary space or ribs has concerned radiologists. The 79 prevalent cancers detected in the 10,000 self-referred woman at the University of Michigan Breast Cancer Detection Demonstration Project were analyzed for number of films required to detect the cancer, relationship of the cancer to the posterior edge of the film, number of occult lesions, tumor size, histologic type, sensitivity of detection method, and number of interval carcinomas. The mammograms were obtained using a dedicated mammographic machine and the upright position, with visualization of the anterior axillary fold on the mediolateral view. The ribs were not imaged. Of the 79 cancers, 76 were detectable on the mammogram. All were visualized on the mediolateral view, while three were not imaged on the craniocaudal view. Twelve percent of the cancers were within 1 cm of the posterior edge of the film. Only six ''interval'' carcinomas were found in the 10,000 patients within the year of the initial examinations; these women had dense P2 or DY mammographic parenchymal patterns. The detected cancers were smaller and had a significantly higher percentage of noninvasive cancers than in a symptomatic clinical population. Thus, properly exposed film mammograms using vigorous breast compression examine the breast adequately without visualizing the ribs

  1. Mammographic feature enhancement by multiscale analysis

    International Nuclear Information System (INIS)

    Laine, A.F.; Schuler, S.; Fan, J.; Huda, W.

    1994-01-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis by overcomplete multiresolution representations. The authors show that efficient representations may be identified within a continuum of scale-space and used to enhance features of importance to mammography. Methods of contrast enhancement are described based on three overcomplete multiscale representations: (1) the dyadic wavelet transform (separable), (2) the var-phi-transform (nonseparable, nonorthogonal), and (3) the hexagonal wavelet transform (nonseparable). Multiscale edges identified within distinct levels of transform space provide local support for image enhancement. Mammograms are reconstructed from wavelet coefficients modified at one or more levels by local and global nonlinear operators. In each case, edges and gain parameters are identified adaptively by a measure of energy within each level of scale-space. The authors show quantitatively that transform coefficients, modified by adaptive nonlinear operators, can make more obvious unseen or barely seen features of mammography without requiring additional radiation. The results are compared with traditional image enhancement techniques by measuring the local contrast of known mammographic features. The authors demonstrate that features extracted from multiresolution representations can provide an adaptive mechanism for accomplishing local contrast enhancement. By improving the visualization of breast pathology, they can improve chances of early detection while requiring less time to evaluate mammograms for most patients

  2. Contour tracing for segmentation of mammographic masses

    International Nuclear Information System (INIS)

    Elter, Matthias; Held, Christian; Wittenberg, Thomas

    2010-01-01

    CADx systems have the potential to support radiologists in the difficult task of discriminating benign and malignant mammographic lesions. The segmentation of mammographic masses from the background tissue is an important module of CADx systems designed for the characterization of mass lesions. In this work, a novel approach to this task is presented. The segmentation is performed by automatically tracing the mass' contour in-between manually provided landmark points defined on the mass' margin. The performance of the proposed approach is compared to the performance of implementations of three state-of-the-art approaches based on region growing and dynamic programming. For an unbiased comparison of the different segmentation approaches, optimal parameters are selected for each approach by means of tenfold cross-validation and a genetic algorithm. Furthermore, segmentation performance is evaluated on a dataset of ROI and ground-truth pairs. The proposed method outperforms the three state-of-the-art methods. The benchmark dataset will be made available with publication of this paper and will be the first publicly available benchmark dataset for mass segmentation.

  3. Development of a 14-digit Hydrologic Unit Code Numbering System for South Carolina

    Science.gov (United States)

    Bower, David E.; Lowry, Claude; Lowery, Mark A.; Hurley, Noel M.

    1999-01-01

    A Hydrologic Unit Map showing the cataloging units, watersheds, and subwatersheds of South Carolina has been developed by the U.S. Geological Survey in cooperation with the South Carolina Department of Health and Environmental Control, funded through a U.S. Environmental Protection Agency 319 Grant, and the U.S. Department of Agriculture, Natural Resources Conservation Service. These delineations represent 8-, 11-, and 14-digit Hydrologic Unit Codes, respectively. This map presents information on drainage, hydrography, and hydrologic boundaries of the water-resources regions, subregions, accounting units, cataloging units, watersheds, and subwatersheds. The source maps for the basin delineations are 1:24,000-scale 7.5-minute series topographic maps and the base maps are from 1:100,000-scale Digital Line Graphs; however, the data are published at a scale of 1:500,000. In addition, an electronic version of the data is provided on a compact disc.Of the 1,022 subwatersheds delineated for this project, 1,004 range in size from 3,000 to 40,000 acres (4.69 to 62.5 square miles). Seventeen subwatersheds are smaller than 3,000 acres and one subwatershed, located on St. Helena Island, is larger than 40,000 acres.This map and its associated codes provide a standardized base for use by water-resource managers and planners in locating, storing, retrieving, and exchanging hydrologic data. In addition, the map can be used for cataloging water-data acquisition activities, geographically organizing hydrologic data, and planning and describing water-use and related land-use activities.

  4. A prototype for a mammographic head and related developments

    Energy Technology Data Exchange (ETDEWEB)

    Amendolia, S.R.; Annovazzi, A.; Bigongiari, A.; Bisogni, M.G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Chianella, M.; Delogu, P.; Fantacci, M.E.; Galimberti, D.; Lanzieri, C.; Lavanga, S.; Novelli, M.; Passuello, G.; Stefanini, A.; Testa, A.; Venturelli, L

    2004-02-01

    The Integrated Mammographic Imaging (IMI) project aims to realize innovative instrumentations for morphological and functional mammography, in particular, one of the research topics is the design and development of a prototype of a mammographic head. Innovative industrial processes for the production of GaAs pixel detectors and for their bump-bonding to the read-out VLSI electronics have been developed by AMS. The data acquisition and processing have been developed by LABEN; the power supply and distribution system has been realized by CAEN; while the integration of the head in a standard mammograph has been carried on by the Laboratori di Ricerca Gilardoni.

  5. A prototype for a mammographic head and related developments

    International Nuclear Information System (INIS)

    Amendolia, S.R.; Annovazzi, A.; Bigongiari, A.; Bisogni, M.G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Chianella, M.; Delogu, P.; Fantacci, M.E.; Galimberti, D.; Lanzieri, C.; Lavanga, S.; Novelli, M.; Passuello, G.; Stefanini, A.; Testa, A.; Venturelli, L.

    2004-01-01

    The Integrated Mammographic Imaging (IMI) project aims to realize innovative instrumentations for morphological and functional mammography, in particular, one of the research topics is the design and development of a prototype of a mammographic head. Innovative industrial processes for the production of GaAs pixel detectors and for their bump-bonding to the read-out VLSI electronics have been developed by AMS. The data acquisition and processing have been developed by LABEN; the power supply and distribution system has been realized by CAEN; while the integration of the head in a standard mammograph has been carried on by the Laboratori di Ricerca Gilardoni

  6. Evaluation of mean glandular dose in a full-field digital mammography unit in Tabriz (IR)

    International Nuclear Information System (INIS)

    Riabi, H. A.; Mehnati, P.; Mesbahi, A.

    2010-01-01

    This study was aimed at evaluating the mean glandular dose (MGD) and affecting factors during mammography examinations by a full-field digital mammography unit. An extensive quality control program was performed to assure that the unit is properly working. Required information including compressed breast thickness (CBT), breast parenchymal pattern and technical factors used for imaging were recorded. An entrance skin exposure measurement was also performed using slabs of polymethylmethacrylate with 2-8 cm thickness. On the basis of recorded information and measured data, the MGD was estimated for 1145 mammography examinations obtained from 298 patients. Mean CBTs of 4.9 and 5.8 cm and MGDs of 2 and 2.4 mGy were observed for cranio-caudal and medio-lateral oblique views, respectively. Significant correlation was seen between MGD and CBT, breast parenchymal pattern and applied kVp and mAs. (authors)

  7. Multilingual Literacies in Transnational Digitally Mediated Contexts: An Exploratory Study of Immigrant Teens in the United States

    Science.gov (United States)

    Lam, Wan Shun Eva; Rosario-Ramos, Enid

    2009-01-01

    This study explores the literacy practices that are involved in transnational social and information networking among youths of immigrant backgrounds in the United States. In particular, it investigates the ways in which young migrants of diverse national origins in the United States are utilising digital media to organise social relationships…

  8. Effect of dose reduction on the detection of mammographic lesions: A mathematical observer model analysis

    International Nuclear Information System (INIS)

    Chawla, Amarpreet S.; Samei, Ehsan; Saunders, Robert; Abbey, Craig; Delong, David

    2007-01-01

    The effect of reduction in dose levels normally used in mammographic screening procedures on the detection of breast lesions were analyzed. Four types of breast lesions were simulated and inserted into clinically-acquired digital mammograms. Dose reduction by 50% and 75% of the original clinically-relevant exposure levels were simulated by adding corresponding simulated noise into the original mammograms. The mammograms were converted into luminance values corresponding to those displayed on a clinical soft-copy display station and subsequently analyzed by Laguerre-Gauss and Gabor channelized Hotelling observer models for differences in detectability performance with reduction in radiation dose. Performance was measured under a signal known exactly but variable detection task paradigm in terms of receiver operating characteristics (ROC) curves and area under the ROC curves. The results suggested that luminance mapping of digital mammograms affects performance of model observers. Reduction in dose levels by 50% lowered the detectability of masses with borderline statistical significance. Dose reduction did not have a statistically significant effect on detection of microcalcifications. The model results indicate that there is room for optimization of dose level in mammographic screening procedures

  9. Karst in the United States: a digital map compilation and database

    Science.gov (United States)

    Weary, David J.; Doctor, Daniel H.

    2014-01-01

    This report describes new digital maps delineating areas of the United States, including Puerto Rico and the U.S. Virgin Islands, having karst or the potential for development of karst and pseudokarst. These maps show areas underlain by soluble rocks and also by volcanic rocks, sedimentary deposits, and permafrost that have potential for karst or pseudokarst development. All 50 States contain rocks with potential for karst development, and about 18 percent of their area is underlain by soluble rocks having karst or the potential for development of karst features. The areas of soluble rocks shown are based primarily on selection from State geologic maps of rock units containing significant amounts of carbonate or evaporite minerals. Areas underlain by soluble rocks are further classified by general climate setting, degree of induration, and degree of exposure. Areas having potential for volcanic pseudokarst are those underlain chiefly by basaltic-flow rocks no older than Miocene in age. Areas with potential for pseudokarst features in sedimentary rocks are in relatively unconsolidated rocks from which pseudokarst features, such as piping caves, have been reported. Areas having potential for development of thermokarst features, mapped exclusively in Alaska, contain permafrost in relatively thick surficial deposits containing ground ice. This report includes a GIS database with links from the map unit polygons to online geologic unit descriptions.

  10. Mammographic Breast Density in a Cohort of Medically Underserved Women

    Science.gov (United States)

    2015-12-01

    was a training year and during Years 2 through 4 a case-control study of obesity , insulin resistance and mammographic breast density was conducted. A...factors including health literacy, and to collect anthropometric measurements and fasting blood, 3) to assay blood for select hormones and growth...factors, 4) to perform statistical analyses to determine the associations between obesity and insulin resistance and mammographic breast density, and 5

  11. The mammographic spectrum of intraductal carcinoma

    International Nuclear Information System (INIS)

    Ikeda, D.M.; Andersson, I.

    1988-01-01

    To analyze the atypical radiographic spectrum of ductal carcinoma in situ (DCIS), the authors retrospectively reviewed the mammograms of 190 women who had biopsy-proved DCIS at Malmo General Hospital between January 1976 and March 1988. Of these, 117 (61.6%) showed clustered microcalcifications as the major abnormality, a finding often associated with DCIS. The remaining 73 women (38.4%) had either negative mammograms (30 women) or radiographic findings not usually associated with DCIS (43 women), including circumscribed masses (15 women) and focal conglomerates of prominent ducts and nodules (12 cases). Since treatment of DCIS may cure the disease, the radiologist should learn to recognize the more unusual mammographic manifestations of intraductal carcinoma

  12. Software Unit Testing during the Development of Digital Reactor Protection System of HTR-PM

    International Nuclear Information System (INIS)

    Guo Chao; Xiong Huasheng; Li Duo; Zhou Shuqiao; Li Jianghai

    2014-01-01

    Reactor Protection System (RPS) of High Temperature Gas-Cooled Reactor - Pebble bed Module (HTR-PM) is the first digital RPS designed and to be operated in the Nuclear Power Plant (NPP) of China, and its development process has receives a lot of concerns around the world. As a 1E-level safety system, the RPS has to be designed and developed following a series of nuclear laws and technical disciplines including software verification and validation (software V&V). Software V&V process demonstrates whether all stages during the software development are performed correctly, completely, accurately, and consistently, and the results of each stage are testable. Software testing is one of the most significant and time-consuming effort during software V&V. In this paper, we give a comprehensive introduction to the software unit testing during the development of RPS in HTR-PM. We first introduce the objective of the testing for our project in the aspects of static testing, black-box testing, and white-box testing. Then the testing techniques, including static testing and dynamic testing, are explained, and the testing strategy we employed is also introduced. We then introduce the principles of three kinds of coverage criteria we used including statement coverage, branch coverage, and the modified condition/decision coverage. As a 1E-level safety software, testing coverage needs to be up to 100% mandatorily. Then we talk the details of safety software testing during software development in HTR-PM, including the organization, methods and tools, testing stages, and testing report. The test result and experiences are shared and finally we draw a conclusion for the unit testing process. The introduction of this paper can contribute to improve the process of unit testing and software development for other digital instrumentation and control systems in NPPs. (author)

  13. Design and implementation of interface units for high speed fiber optics local area networks and broadband integrated services digital networks

    Science.gov (United States)

    Tobagi, Fouad A.; Dalgic, Ismail; Pang, Joseph

    1990-01-01

    The design and implementation of interface units for high speed Fiber Optic Local Area Networks and Broadband Integrated Services Digital Networks are discussed. During the last years, a number of network adapters that are designed to support high speed communications have emerged. This approach to the design of a high speed network interface unit was to implement package processing functions in hardware, using VLSI technology. The VLSI hardware implementation of a buffer management unit, which is required in such architectures, is described.

  14. Development of terminology for mammographic techniques for radiological technologists.

    Science.gov (United States)

    Yagahara, Ayako; Yokooka, Yuki; Tsuji, Shintaro; Nishimoto, Naoki; Uesugi, Masahito; Muto, Hiroshi; Ohba, Hisateru; Kurowarabi, Kunio; Ogasawara, Katsuhiko

    2011-07-01

    We are developing a mammographic ontology to share knowledge of the mammographic domain for radiologic technologists, with the aim of improving mammographic techniques. As a first step in constructing the ontology, we used mammography reference books to establish mammographic terminology for identifying currently available knowledge. This study proceeded in three steps: (1) determination of the domain and scope of the terminology, (2) lexical extraction, and (3) construction of hierarchical structures. We extracted terms mainly from three reference books and constructed the hierarchical structures manually. We compared features of the terms extracted from the three reference books. We constructed a terminology consisting of 440 subclasses grouped into 19 top-level classes: anatomic entity, image quality factor, findings, material, risk, breast, histological classification of breast tumors, role, foreign body, mammographic technique, physics, purpose of mammography examination, explanation of mammography examination, image development, abbreviation, quality control, equipment, interpretation, and evaluation of clinical imaging. The number of terms that occurred in the subclasses varied depending on which reference book was used. We developed a terminology of mammographic techniques for radiologic technologists consisting of 440 terms.

  15. Mammographic Imaging Studies Using the Monte Carlo Image Simulation-Differential Sampling (MCMIS-DS) Code

    International Nuclear Information System (INIS)

    Kuruvilla Verghese

    2002-01-01

    This report summarizes the highlights of the research performed under the 1-year NEER grant from the Department of Energy. The primary goal of this study was to investigate the effects of certain design changes in the Fisher Senoscan mammography system and in the degree of breast compression on the discernability of microcalcifications in calcification clusters often observed in mammograms with tumor lesions. The most important design change that one can contemplate in a digital mammography system to improve resolution of calcifications is the reduction of pixel dimensions of the digital detector. Breast compression is painful to the patient and is though to be a deterrent to women to get routine mammographic screening. Calcification clusters often serve as markers (indicators ) of breast cancer

  16. Introduction: Philosophers of the World Unite! Theorising Digital Labour and Virtual Work—Definitions, Dimensions, and Forms

    Directory of Open Access Journals (Sweden)

    Marisol Sandoval

    2014-09-01

    Full Text Available In 1845, Karl Marx (1845, 571 formulated the 11th Feuerbach Thesis: “The philosophers have only interpreted the world in various ways; the point is to change it.” Today, interpreting the world has become an important form of labour that is expressed on and with the help of digital media. In this context it has become common to talk about digital labour and virtual work. Yet the changes that digital, social, and mobile media bring about in the world of labour and work have thus far only been little theoretically interpreted. In order to change the information society for the better, we first have to interpret digital labour with the help of critical theories. Social theorists of the world from different fields, backgrounds, interdisciplines, transdisciplines, and disciplines have to unite for this collective philosophical task. This special issue of tripleC: Communication, Capitalism & Critique aims to contribute to building a theoretical framework for the critical analysis of digital labour, virtual work, and related concepts that can initiate further debates, inform empirical studies, and inspire social struggles connected to work and labour in and beyond digital capitalism. The papers collected in this special issue (a provide systematic definitions of digital labour, (b analyse its specific dimension, and (c discuss different forms of digital labour.

  17. Single x-ray absorptiometry method for the quantitative mammographic measure of fibroglandular tissue volume

    International Nuclear Information System (INIS)

    Malkov, Serghei; Wang, Jeff; Kerlikowske, Karla; Cummings, Steven R.; Shepherd, John A.

    2009-01-01

    Purpose: This study describes the design and characteristics of a highly accurate, precise, and automated single-energy method to quantify percent fibroglandular tissue volume (%FGV) and fibroglandular tissue volume (FGV) using digital screening mammography. Methods: The method uses a breast tissue-equivalent phantom in the unused portion of the mammogram as a reference to estimate breast composition. The phantom is used to calculate breast thickness and composition for each image regardless of x-ray technique or the presence of paddle tilt. The phantom adheres to the top of the mammographic compression paddle and stays in place for both craniocaudal and mediolateral oblique screening views. We describe the automated method to identify the phantom and paddle orientation with a three-dimensional reconstruction least-squares technique. A series of test phantoms, with a breast thickness range of 0.5-8 cm and a %FGV of 0%-100%, were made to test the accuracy and precision of the technique. Results: Using test phantoms, the estimated repeatability standard deviation equaled 2%, with a ±2% accuracy for the entire thickness and density ranges. Without correction, paddle tilt was found to create large errors in the measured density values of up to 7%/mm difference from actual breast thickness. This new density measurement is stable over time, with no significant drifts in calibration noted during a four-month period. Comparisons of %FGV to mammographic percent density and left to right breast %FGV were highly correlated (r=0.83 and 0.94, respectively). Conclusions: An automated method for quantifying fibroglandular tissue volume has been developed. It exhibited good accuracy and precision for a broad range of breast thicknesses, paddle tilt angles, and %FGV values. Clinical testing showed high correlation to mammographic density and between left and right breasts.

  18. Reduction of false-positive recalls using a computerized mammographic image feature analysis scheme

    Science.gov (United States)

    Tan, Maxine; Pu, Jiantao; Zheng, Bin

    2014-08-01

    The high false-positive recall rate is one of the major dilemmas that significantly reduce the efficacy of screening mammography, which harms a large fraction of women and increases healthcare cost. This study aims to investigate the feasibility of helping reduce false-positive recalls by developing a new computer-aided diagnosis (CAD) scheme based on the analysis of global mammographic texture and density features computed from four-view images. Our database includes full-field digital mammography (FFDM) images acquired from 1052 recalled women (669 positive for cancer and 383 benign). Each case has four images: two craniocaudal (CC) and two mediolateral oblique (MLO) views. Our CAD scheme first computed global texture features related to the mammographic density distribution on the segmented breast regions of four images. Second, the computed features were given to two artificial neural network (ANN) classifiers that were separately trained and tested in a ten-fold cross-validation scheme on CC and MLO view images, respectively. Finally, two ANN classification scores were combined using a new adaptive scoring fusion method that automatically determined the optimal weights to assign to both views. CAD performance was tested using the area under a receiver operating characteristic curve (AUC). The AUC = 0.793  ±  0.026 was obtained for this four-view CAD scheme, which was significantly higher at the 5% significance level than the AUCs achieved when using only CC (p = 0.025) or MLO (p = 0.0004) view images, respectively. This study demonstrates that a quantitative assessment of global mammographic image texture and density features could provide useful and/or supplementary information to classify between malignant and benign cases among the recalled cases, which may eventually help reduce the false-positive recall rate in screening mammography.

  19. Phasor Measurement Unit and Phasor Data Concentrator test with Real Time Digital Simulator

    DEFF Research Database (Denmark)

    Diakos, Konstantinos; Wu, Qiuwei; Nielsen, Arne Hejde

    2014-01-01

    that is able to derive and communicate synchrophasor measurements of different parts of the power network and the development of tests, according to IEEE standards, that evaluate the performance of PMUs and PDCs. The tests are created by using a Real Time Digital Simulation (RTDS) system. The results obtained......The main focus of the electrical engineers nowadays, is to develop a smart grid that is able to monitor, evaluate and control the power system operation. The integration of Intelligent Electronic Devices (IED s) to the power network, is a strong indication of the inclination to lead the power...... network to a more reliable, secure and economic operation. The implementation of these devices though, demands the warranty of a secure operation and high-accuracy performance. This paper describes the procedure of establishing a PMU (Phasor Measurement Unit)–PDC (Phasor Data Concentrator) platform...

  20. A deep learning method for classifying mammographic breast density categories.

    Science.gov (United States)

    Mohamed, Aly A; Berg, Wendie A; Peng, Hong; Luo, Yahong; Jankowitz, Rachel C; Wu, Shandong

    2018-01-01

    Mammographic breast density is an established risk marker for breast cancer and is visually assessed by radiologists in routine mammogram image reading, using four qualitative Breast Imaging and Reporting Data System (BI-RADS) breast density categories. It is particularly difficult for radiologists to consistently distinguish the two most common and most variably assigned BI-RADS categories, i.e., "scattered density" and "heterogeneously dense". The aim of this work was to investigate a deep learning-based breast density classifier to consistently distinguish these two categories, aiming at providing a potential computerized tool to assist radiologists in assigning a BI-RADS category in current clinical workflow. In this study, we constructed a convolutional neural network (CNN)-based model coupled with a large (i.e., 22,000 images) digital mammogram imaging dataset to evaluate the classification performance between the two aforementioned breast density categories. All images were collected from a cohort of 1,427 women who underwent standard digital mammography screening from 2005 to 2016 at our institution. The truths of the density categories were based on standard clinical assessment made by board-certified breast imaging radiologists. Effects of direct training from scratch solely using digital mammogram images and transfer learning of a pretrained model on a large nonmedical imaging dataset were evaluated for the specific task of breast density classification. In order to measure the classification performance, the CNN classifier was also tested on a refined version of the mammogram image dataset by removing some potentially inaccurately labeled images. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to measure the accuracy of the classifier. The AUC was 0.9421 when the CNN-model was trained from scratch on our own mammogram images, and the accuracy increased gradually along with an increased size of training samples

  1. Influence of lifestyle factors on mammographic density in postmenopausal women.

    Directory of Open Access Journals (Sweden)

    Judith S Brand

    Full Text Available BACKGROUND: Mammographic density is a strong risk factor for breast cancer. Apart from hormone replacement therapy (HRT, little is known about lifestyle factors that influence breast density. METHODS: We examined the effect of smoking, alcohol and physical activity on mammographic density in a population-based sample of postmenopausal women without breast cancer. Lifestyle factors were assessed by a questionnaire and percentage and area measures of mammographic density were measured using computer-assisted software. General linear models were used to assess the association between lifestyle factors and mammographic density and effect modification by body mass index (BMI and HRT was studied. RESULTS: Overall, alcohol intake was positively associated with percent mammographic density (P trend  = 0.07. This association was modified by HRT use (P interaction  = 0.06: increasing alcohol intake was associated with increasing percent density in current HRT users (P trend  = 0.01 but not in non-current users (P trend  = 0.82. A similar interaction between alcohol and HRT was found for the absolute dense area, with a positive association being present in current HRT users only (P interaction  = 0.04. No differences in mammographic density were observed across categories of smoking and physical activity, neither overall nor in stratified analyses by BMI and HRT use. CONCLUSIONS: Increasing alcohol intake is associated with an increase in mammography density, whereas smoking and physical activity do not seem to influence density. The observed interaction between alcohol and HRT may pose an opportunity for HRT users to lower their mammographic density and breast cancer risk.

  2. Spectral analysis of mammographic images using a multitaper method

    International Nuclear Information System (INIS)

    Wu Gang; Mainprize, James G.; Yaffe, Martin J.

    2012-01-01

    Purpose: Power spectral analysis in radiographic images is conventionally performed using a windowed overlapping averaging periodogram. This study describes an alternative approach using a multitaper technique and compares its performance with that of the standard method. This tool will be valuable in power spectrum estimation of images, whose content deviates significantly from uniform white noise. The performance of the multitaper approach will be evaluated in terms of spectral stability, variance reduction, bias, and frequency precision. The ultimate goal is the development of a useful tool for image quality assurance. Methods: A multitaper approach uses successive data windows of increasing order. This mitigates spectral leakage allowing one to calculate a reduced-variance power spectrum. The multitaper approach will be compared with the conventional power spectrum method in several typical situations, including the noise power spectra (NPS) measurements of simulated projection images of a uniform phantom, NPS measurement of real detector images of a uniform phantom for two clinical digital mammography systems, and the estimation of the anatomic noise in mammographic images (simulated images and clinical mammograms). Results: Examination of spectrum variance versus frequency resolution and bias indicates that the multitaper approach is superior to the conventional single taper methods in the prevention of spectrum leakage and variance reduction. More than four times finer frequency precision can be achieved with equivalent or less variance and bias. Conclusions: Without any shortening of the image data length, the bias is smaller and the frequency resolution is higher with the multitaper method, and the need to compromise in the choice of regions of interest size to balance between the reduction of variance and the loss of frequency resolution is largely eliminated.

  3. Digital breast tomosynthesis

    International Nuclear Information System (INIS)

    Haegele, Julian; Barkhausen, Joerg; Pursche, Telja; Schaefer, Fritz K.W.

    2015-01-01

    In digital breast tomosynthesis a digital tomographic data set with a very high spatial resolution is reconstructed from low-dose projections collected over a limited rotation angle. This allows a very detailed assessment of e. g. masses and architectural distortions. The average glandular dose is comparable to 2 D mammography. First clinical studies demonstrated that tomosynthesis is able to supply important additional information in suspicious mammographic findings. In comparison to projection mammography, tomosynthesis shows an at least comparable diagnostic accuracy. In everyday practice, tomosynthesis is currently mostly used for further evaluation of suspicious findings in mammography.

  4. Characterization of mammographic masses based on level set segmentation with new image features and patient information

    International Nuclear Information System (INIS)

    Shi Jiazheng; Sahiner, Berkman; Chan Heangping; Ge Jun; Hadjiiski, Lubomir; Helvie, Mark A.; Nees, Alexis; Wu Yita; Wei Jun; Zhou Chuan; Zhang Yiheng; Cui Jing

    2008-01-01

    Computer-aided diagnosis (CAD) for characterization of mammographic masses as malignant or benign has the potential to assist radiologists in reducing the biopsy rate without increasing false negatives. The purpose of this study was to develop an automated method for mammographic mass segmentation and explore new image based features in combination with patient information in order to improve the performance of mass characterization. The authors' previous CAD system, which used the active contour segmentation, and morphological, textural, and spiculation features, has achieved promising results in mass characterization. The new CAD system is based on the level set method and includes two new types of image features related to the presence of microcalcifications with the mass and abruptness of the mass margin, and patient age. A linear discriminant analysis (LDA) classifier with stepwise feature selection was used to merge the extracted features into a classification score. The classification accuracy was evaluated using the area under the receiver operating characteristic curve. The authors' primary data set consisted of 427 biopsy-proven masses (200 malignant and 227 benign) in 909 regions of interest (ROIs) (451 malignant and 458 benign) from multiple mammographic views. Leave-one-case-out resampling was used for training and testing. The new CAD system based on the level set segmentation and the new mammographic feature space achieved a view-based A z value of 0.83±0.01. The improvement compared to the previous CAD system was statistically significant (p=0.02). When patient age was included in the new CAD system, view-based and case-based A z values were 0.85±0.01 and 0.87±0.02, respectively. The study also demonstrated the consistency of the newly developed CAD system by evaluating the statistics of the weights of the LDA classifiers in leave-one-case-out classification. Finally, an independent test on the publicly available digital database for screening

  5. Diagnostic Performance of Mammographic Texture Analysis in the Differential Diagnosis of Benign and Malignant Breast Tumors.

    Science.gov (United States)

    Li, Zhiming; Yu, Lan; Wang, Xin; Yu, Haiyang; Gao, Yuanxiang; Ren, Yande; Wang, Gang; Zhou, Xiaoming

    2017-11-09

    The purpose of this study was to investigate the diagnostic performance of mammographic texture analysis in the differential diagnosis of benign and malignant breast tumors. Digital mammography images were obtained from the Picture Archiving and Communication System at our institute. Texture features of mammographic images were calculated. Mann-Whitney U test was used to identify differences between the benign and malignant group. The receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic performance of texture features. Significant differences of texture features of histogram, gray-level co-occurrence matrix (GLCM) and run length matrix (RLM) were found between the benign and malignant breast group (P  .05). The AUROCs of imaging-based diagnosis, texture analysis, and imaging-based diagnosis combined with texture analysis were 0.873, 0.863, and 0.961, respectively. When imaging-based diagnosis was combined with texture analysis, the AUROC was higher than that of imaging-based diagnosis or texture analysis (P benign and malignant breast tumors. Furthermore, the combination of imaging-based diagnosis and texture analysis can significantly improve diagnostic performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Image enhancement by using IDL for a mammographic x-ray image in Medical Physics Laboratory

    International Nuclear Information System (INIS)

    Asmaliza Hashim; Md Saion Salikin; Wan Hazlinda Ismail; Norriza Mohd Isa; Azuhar Ripin

    2004-01-01

    Digital image enhancement technique can have a significant impact on the diagnostic quality of a radiographic image. The main aim of image enhancement is to process the image so that the enhanced image is clearer and more useful for specific application. There are three types of image enhancement namely noise reduction, edge enhancement and contrast enhancement. The objective of this project is to enhance the mammographic image by using Interactive Data Language (IDL) software in spatial and frequency domain by using various methods. In spatial domain method, direct manipulation of pixel in an image is used whereas, in frequency domain method, modifying the spectral component or Fourier Transform of an image is used In order to obtain the good quality mammographic image, breast phantom Model 12A with 4.0 cm compressed thickness and Bennett Model DMF- 150 Mammography Machine with various kV and mA are employed. The results of enhanced image with selected technique by using IDL are presented in this paper. (Author)

  7. Mass Detection in Mammographic Images Using Wavelet Processing and Adaptive Threshold Technique.

    Science.gov (United States)

    Vikhe, P S; Thool, V R

    2016-04-01

    Detection of mass in mammogram for early diagnosis of breast cancer is a significant assignment in the reduction of the mortality rate. However, in some cases, screening of mass is difficult task for radiologist, due to variation in contrast, fuzzy edges and noisy mammograms. Masses and micro-calcifications are the distinctive signs for diagnosis of breast cancer. This paper presents, a method for mass enhancement using piecewise linear operator in combination with wavelet processing from mammographic images. The method includes, artifact suppression and pectoral muscle removal based on morphological operations. Finally, mass segmentation for detection using adaptive threshold technique is carried out to separate the mass from background. The proposed method has been tested on 130 (45 + 85) images with 90.9 and 91 % True Positive Fraction (TPF) at 2.35 and 2.1 average False Positive Per Image(FP/I) from two different databases, namely Mammographic Image Analysis Society (MIAS) and Digital Database for Screening Mammography (DDSM). The obtained results show that, the proposed technique gives improved diagnosis in the early breast cancer detection.

  8. Double-blind randomized 12-month soy intervention had no effects on breast MRI fibroglandular tissue density or mammographic density

    Science.gov (United States)

    Wu, Anna H.; Spicer, Darcy; Garcia, Agustin; Tseng, Chiu-Chen; Hovanessian-Larsen, Linda; Sheth, Pulin; Martin, Sue Ellen; Hawes, Debra; Russell, Christy; McDonald, Heather; Tripathy, Debu; Su, Min-Ying; Ursin, Giske; Pike, Malcolm C.

    2015-01-01

    Soy supplementation by breast cancer patients remains controversial. No controlled intervention studies have investigated the effects of soy supplementation on mammographic density in breast cancer patients. We conducted a double-blind, randomized, placebo-controlled intervention study in previously treated breast cancer patients (n=66) and high-risk women (n=29). We obtained digital mammograms and breast magnetic resonance imaging (MRI) scans at baseline and after 12 months of daily soy (50 mg isoflavones per day) (n=46) or placebo (n=49) tablet supplementation. The total breast area (MA) and the area of mammographic density (MD) on the mammogram was measured using a validated computer-assisted method, and mammographic density percent (MD% = 100 × MD/MA) was determined. A well-tested computer algorithm was used to quantitatively measure the total breast volume (TBV) and fibroglandular tissue volume (FGV) on the breast MRI, and the FGV percent (FGV% = 100 × FGV/TBV) was calculated. On the basis of plasma soy isoflavone levels, compliance was excellent. Small decreases in MD% measured by the ratios of month 12 to baseline levels, were seen in the soy (0.95) and the placebo (0.87) groups; these changes did not differ between the treatments (P=0.38). Small decreases in FGV% were also found in both the soy (0.90) and the placebo (0.92) groups; these changes also did not differ between the treatments (P=0.48). Results were comparable in breast cancer patients and high-risk women. We found no evidence that soy supplementation would decrease mammographic density and that MRI might be more sensitive to changes in density than mammography. PMID:26276750

  9. Mammographic density and histopathologic characteristics of screen-detected tumors in the Norwegian Breast Cancer Screening Program

    International Nuclear Information System (INIS)

    Moshina, Nataliia; Ursin, Giske; Hoff, Solveig Roth; Akslen, Lars A; Roman, Marta; Sebuødegård, Sofie; Hofvind, Solveig

    2015-01-01

    High mammographic density might mask breast tumors, resulting in delayed diagnosis or missed cancers. To investigate the association between mammographic density and histopathologic tumor characteristics (histologic type, size, grade, and lymph node status) among women screened in the Norwegian Breast Cancer Screening Program. Information about 1760 screen-detected ductal carcinoma in situ (DCIS) and 7366 invasive breast cancers diagnosed among women aged 50–69 years, 1996–2010, was analyzed. The screening mammograms were classified subjectively according to the amount of fibroglandular tissue into fatty, medium dense, and dense by breast radiologists. Chi-square test was used to compare the distribution of tumor characteristics by mammographic density. Odds ratio (OR) of tumor characteristics by density was estimated by means of logistic regression, adjusting for screening mode (screen-film and full-field digital mammography), and age. Mean and median tumor size of invasive breast cancers was 13.8 and 12 mm, respectively, for women with fatty breasts, and 16.2 and 14 mm for those with dense breasts. Lymph node positive tumors were identified among 20.6% of women with fatty breasts compared with 27.2% of those with dense breasts (P < 0.001). The proportion of DCIS was significantly lower for women with fatty (15.8%) compared with dense breasts (22.0%). Women with dense breasts had an increased risk of large (OR, 1.44; 95% CI, 1.18–1.73) and lymph node positive tumors (OR, 1.26; 95% CI, 1.05–1.51) compared with women with fatty and medium dense breasts. High mammographic density was positively associated with tumor size and lymph node positive tumors

  10. Morphological topology generation of a digital fluid power displacement unit using Chebychev-Grübler-Kutzbach constraint

    DEFF Research Database (Denmark)

    Johansen, Per; Roemer, Daniel Beck; Andersen, Torben O.

    2015-01-01

    The task of designing a digital fluid power displacement unit entails a choice of topology. Consequently, this choice entails a need for knowledge of the various applicable topologies to choose from. In this paper a morphological topology generation approach is used to derive a series of radial...

  11. Mammographic image restoration using maximum entropy deconvolution

    International Nuclear Information System (INIS)

    Jannetta, A; Jackson, J C; Kotre, C J; Birch, I P; Robson, K J; Padgett, R

    2004-01-01

    An image restoration approach based on a Bayesian maximum entropy method (MEM) has been applied to a radiological image deconvolution problem, that of reduction of geometric blurring in magnification mammography. The aim of the work is to demonstrate an improvement in image spatial resolution in realistic noisy radiological images with no associated penalty in terms of reduction in the signal-to-noise ratio perceived by the observer. Images of the TORMAM mammographic image quality phantom were recorded using the standard magnification settings of 1.8 magnification/fine focus and also at 1.8 magnification/broad focus and 3.0 magnification/fine focus; the latter two arrangements would normally give rise to unacceptable geometric blurring. Measured point-spread functions were used in conjunction with the MEM image processing to de-blur these images. The results are presented as comparative images of phantom test features and as observer scores for the raw and processed images. Visualization of high resolution features and the total image scores for the test phantom were improved by the application of the MEM processing. It is argued that this successful demonstration of image de-blurring in noisy radiological images offers the possibility of weakening the link between focal spot size and geometric blurring in radiology, thus opening up new approaches to system optimization

  12. Mammographic features of isolated tuberculous mastitis

    International Nuclear Information System (INIS)

    Al-Marri, Mohammed R.; Aref, Essam; Omar, Ahamed J.

    2005-01-01

    To present the mammography findings in 8 patients with tuberculosis (TB) of the breast, with a review of the literature. This study is a retrospective data collection. Each chart with confirmed breast TB based on bacteriology or pathologic findings was analyzed for clinical presentation, gender, nationality, demographic data, prior history of TB, investigation, management, mammographic findings and ultrasound, when available. Mammograms were reviewed by 2 consultant radiologists without knowing the previous diagnosis or the nature of the study. The study was carried out at The State Tuberculosis Registry and Radiology Department, Hamad General Hospital, State of Qatar, from 1990 to 2002. Out of 13 females with TB mastitis, only 8 cases had mammograms preoperatively. The incidence of breast TB in Qatar is rare (1/1000 mammograms per year). Three types of TB mastitis were identified in our study; the nodular (50%), the diffuse (37.5%) of which 77% were limited to one sector of the breast and the sclerosing (12.5%) mastitis. Three patients (43%) were reported as carcinoma. Although mammography identified 3 types of TB, it was not helpful in differentiating TB from carcinoma of the breast. However, the careful evaluation of the degree of density and trabecular thickening of the mass in relation to it size might reduce the number of false positive cases of carcinoma diagnosed with mammograms. Biopsy specimen remains the best diagnostic tool in TB mastitis. (author)

  13. Mammographic features of isolated tuberculous mastitis.

    Science.gov (United States)

    Al-Marri, Mohammed R; Aref, Essam; Omar, Ahamed J

    2005-04-01

    To present the mammography findings in 8 patients with tuberculosis (TB) of the breast, with a review of the literature. This study is a retrospective data collection. Each chart with confirmed breast TB based on bacteriology or pathologic findings was analyzed for clinical presentation, gender, nationality, demographic data, prior history of TB, investigation, management, mammographic findings and ultrasound, when available. Mammograms were reviewed by 2 consultant radiologists without knowing the previous diagnosis or the nature of the study. The study was carried out at The State Tuberculosis Registry and Radiology Department, Hamad General Hospital, State of Qatar, from 1990 to 2002. Out of 13 females with TB mastitis, only 8 cases had mammograms preoperatively. The incidence of breast TB in Qatar is rare (1/1000 mammograms per year). Three types of TB mastitis were identified in our study; the nodular (50%), the diffuse (37.5%) of which 77% were limited to one sector of the breast and the sclerosing (12.5%) mastitis. Three patients (43%) were reported as carcinoma. Although mammography identified 3 types of TB, it was not helpful in differentiating TB from carcinoma of the breast. However, the careful evaluation of the degree of density and trabecular thickening of the mass in relation to it size might reduce the number of false positive cases of carcinoma diagnosed with mammograms. Biopsy specimen remains the best diagnostic tool in TB mastitis.

  14. Circumscribed breast carcinoma: Mammographic and sonographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Soo Young; Lee, Yul; Park, Ki Soon; Lee, Ke Sook [College of Medicine, Hallym University, Seoul (Korea, Republic of)

    1992-03-15

    Circumscribe breast cancer is a well demarcated mass with or without a lobulated border simulating a benign tumor like fibroadenoma on mammography or breast US and is reported as approximate 10% of the incidence among primary breast carcinoma(1.2). Pathologically medullary, colloid, papillary, intraductal and rarely invasive ductal carcinomas are included in this group which show the less intense desmoplastic reaction than the scirrhous type cancer, resulting in the most favorable prognosis of all carcinoma of the breast. Among 214 primary breast carcinoma during the past 8 years, we experienced 6 case of pathologically proven circumscribed breast cancer(2 cases of medullary carcinoma, 1 of colloid carcinoma, 1 of intracystic papillary carcinoma, 2 of comedo type intraductal carcinoma). Clinically 2 cases showed bloody nipple discharge from one hole of a unilateral nipple orifice. Mammography showed a well circumscribed nodule with or without partial lobular contour and no pathologic calcification. Breast sonographic findings were a well defined heterogeneous hypoechoic nodule with weak posterior acoustic enhancement. Characteristically a thin dilated lactiferous duct between the mass and the nipple on US could be detected in 2 cases which clinically was accompanied by bloody nipple discharge. Although the mammographic criteria is promising as benign tumor, the possibility of circumscribed as benign tumor, the possibility of circumscribed breast carcinoma must be considered in heterogeneous hypoechoic nodule with weak posterior acoustic enhancement in US, especially in the presence of a dilated lactiferous duct between the mass and the nipple with bloody nipple discharge.

  15. Automated mammographic breast density estimation using a fully convolutional network.

    Science.gov (United States)

    Lee, Juhun; Nishikawa, Robert M

    2018-03-01

    The purpose of this study was to develop a fully automated algorithm for mammographic breast density estimation using deep learning. Our algorithm used a fully convolutional network, which is a deep learning framework for image segmentation, to segment both the breast and the dense fibroglandular areas on mammographic images. Using the segmented breast and dense areas, our algorithm computed the breast percent density (PD), which is the faction of dense area in a breast. Our dataset included full-field digital screening mammograms of 604 women, which included 1208 mediolateral oblique (MLO) and 1208 craniocaudal (CC) views. We allocated 455, 58, and 91 of 604 women and their exams into training, testing, and validation datasets, respectively. We established ground truth for the breast and the dense fibroglandular areas via manual segmentation and segmentation using a simple thresholding based on BI-RADS density assessments by radiologists, respectively. Using the mammograms and ground truth, we fine-tuned a pretrained deep learning network to train the network to segment both the breast and the fibroglandular areas. Using the validation dataset, we evaluated the performance of the proposed algorithm against radiologists' BI-RADS density assessments. Specifically, we conducted a correlation analysis between a BI-RADS density assessment of a given breast and its corresponding PD estimate by the proposed algorithm. In addition, we evaluated our algorithm in terms of its ability to classify the BI-RADS density using PD estimates, and its ability to provide consistent PD estimates for the left and the right breast and the MLO and CC views of the same women. To show the effectiveness of our algorithm, we compared the performance of our algorithm against a state of the art algorithm, laboratory for individualized breast radiodensity assessment (LIBRA). The PD estimated by our algorithm correlated well with BI-RADS density ratings by radiologists. Pearson's rho values of

  16. Association between mammographic density and pregnancies relative to age and BMI: a breast cancer case-only analysis.

    Science.gov (United States)

    Hack, Carolin C; Emons, Julius; Jud, Sebastian M; Heusinger, Katharina; Adler, Werner; Gass, Paul; Haeberle, Lothar; Heindl, Felix; Hein, Alexander; Schulz-Wendtland, Rüdiger; Uder, Michael; Hartmann, Arndt; Beckmann, Matthias W; Fasching, Peter A; Pöhls, Uwe G

    2017-12-01

    Percentage mammographic density (PMD) is a major risk factor for breast cancer (BC). It is strongly associated with body mass index (BMI) and age, which are themselves risk factors for breast cancer. This analysis investigated the association between the number of full-term pregnancies and PMD in different subgroups relative to age and BMI. Patients were identified in the breast cancer database of the University Breast Center for Franconia. A total of 2410 patients were identified, for whom information on parity, age, and BMI, and a mammogram from the time of first diagnosis were available for assessing PMD. Linear regression analyses were conducted to investigate the influence on PMD of the number of full-term pregnancies (FTPs), age, BMI, and interaction terms between them. As in previous studies, age, number of FTPs, and BMI were found to be associated with PMD in the expected direction. However, including the respective interaction terms improved the prediction of PMD even further. Specifically, the association between PMD and the number of FTPs differed in young patients under the age of 45 (mean decrease of 0.37 PMD units per pregnancy) from the association in older age groups (mean decrease between 2.29 and 2.39 PMD units). BMI did not alter the association between PMD and the number of FTPs. The effect of pregnancies on mammographic density does not appear to become apparent before the age of menopause. The mechanism that drives the effect of pregnancies on mammographic density appears to be counter-regulated by other influences on mammographic density in younger patients.

  17. Fibroadenomas Frequency in uncertain mammographic lesions: Histology Correlation

    International Nuclear Information System (INIS)

    Hincapie Uribe, Ana Lucia; Patino Pacheco, Jairo H; Restrepo Mejia, Ana Lucia

    1997-01-01

    Purpose was to determine the frequency of fibroadenomas in non-palpable mammographic lesions, histologically evaluated and describe its radiological characteristics according to the type of mammographic presentation and classification. 60 (8.6%) fibroadenomas were found in 692 biopsies performed. 50% of these were mammographicaly classified as category 3 and 50% in the category 4. 66.6% of them were nodules, 20% isolated calcifications and nodules with calcifications 13.3%. fibroadenomas were 26.4% of nodules in category 3 and 18.8% of them in category 4

  18. Teleradiology in a neonatal intensive care unit: Comparison between the interpretation of transmitted digital images and film radiographs

    International Nuclear Information System (INIS)

    McFee, W.H.; Bramson, R.T.; Cates, J.D.; Curran, J.S.

    1987-01-01

    Using a Raytel teleradiology system, a prospective comparison was made between the interpretations of 700 transmitted digital images and the film radiographs from which these digital images were made. The original films consisted of all of the radiographs obtained from the infants in a 40-bed level III neonatal intensive care unit over a 6-week period. Interpretations were done by two radiologists, initially from transmitted images and subsequently from the original films. Comparison of the interpretations demonstrates a remarkably high degree of correlation, with less than 0.5% clinically significant discrepancies reported

  19. 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.)

  20. Study of quality perception in medical images based on comparison of contrast enhancement techniques in mammographic images

    Science.gov (United States)

    Matheus, B.; Verçosa, L. B.; Barufaldi, B.; Schiabel, H.

    2014-03-01

    With the absolute prevalence of digital images in mammography several new tools became available for radiologist; such as CAD schemes, digital zoom and contrast alteration. This work focuses in contrast variation and how the radiologist reacts to these changes when asked to evaluated image quality. Three contrast enhancing techniques were used in this study: conventional equalization, CCB Correction [1] - a digitization correction - and value subtraction. A set of 100 images was used in tests from some available online mammographic databases. The tests consisted of the presentation of all four versions of an image (original plus the three contrast enhanced images) to the specialist, requested to rank each one from the best up to worst quality for diagnosis. Analysis of results has demonstrated that CCB Correction [1] produced better images in almost all cases. Equalization, which mathematically produces a better contrast, was considered the worst for mammography image quality enhancement in the majority of cases (69.7%). The value subtraction procedure produced images considered better than the original in 84% of cases. Tests indicate that, for the radiologist's perception, it seems more important to guaranty full visualization of nuances than a high contrast image. Another result observed is that the "ideal" scanner curve does not yield the best result for a mammographic image. The important contrast range is the middle of the histogram, where nodules and masses need to be seen and clearly distinguished.

  1. A biomechanical model of mammographic compressions.

    Science.gov (United States)

    Chung, J H; Rajagopal, V; Nielsen, P M F; Nash, M P

    2008-02-01

    A number of biomechanical models have been proposed to improve nonrigid registration techniques for multimodal breast image alignment. A deformable breast model may also be useful for overcoming difficulties in interpreting 2D X-ray projections (mammograms) of 3D volumes (breast tissues). If a deformable model could accurately predict the shape changes that breasts undergo during mammography, then the model could serve to localize suspicious masses (visible in mammograms) in the unloaded state, or in any other deformed state required for further investigations (such as biopsy or other medical imaging modalities). In this paper, we present a validation study that was conducted in order to develop a biomechanical model based on the well-established theory of continuum mechanics (finite elasticity theory with contact mechanics) and demonstrate its use for this application. Experimental studies using gel phantoms were conducted to test the accuracy in predicting mammographic-like deformations. The material properties of the gel phantom were estimated using a nonlinear optimization process, which minimized the errors between the experimental and the model-predicted surface data by adjusting the parameter associated with the neo-Hookean constitutive relation. Two compressions (the equivalent of cranio-caudal and medio-lateral mammograms) were performed on the phantom, and the corresponding deformations were recorded using a MRI scanner. Finite element simulations were performed to mimic the experiments using the estimated material properties with appropriate boundary conditions. The simulation results matched the experimental recordings of the deformed phantom, with a sub-millimeter root-mean-square error for each compression state. Having now validated our finite element model of breast compression, the next stage is to apply the model to clinical images.

  2. Characterization of a clinical unit for digital radiography based on irradiation side sampling technology

    Energy Technology Data Exchange (ETDEWEB)

    Rivetti, Stefano [Fisica Medica, Ospedale di Sassuolo S.p.A., 41049 Sassuolo (Italy); Lanconelli, Nico [Alma Mater Studiorum, Physics Department, University of Bologna, 40127 Bologna (Italy); Bertolini, Marco; Nitrosi, Andrea [Medical Physics Unit, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, 42123 Reggio Emilia (Italy); Burani, Aldo [Ospedale di Sassuolo S.p.A., 41049 Sassuolo (Italy)

    2013-10-15

    Purpose: A characterization of a clinical unit for digital radiography (FUJIFILM FDR D-EVO) is presented. This system is based on the irradiation side sampling (ISS) technology and can be equipped with two different scintillators: one traditional gadolinium-oxysulphide phosphor (GOS) and a needle structured cesium iodide (CsI) phosphor panel.Methods: The characterization was achieved in terms of response curve, modulation transfer function (MTF), noise power spectra (NPS), detective quantum efficiency (DQE), and psychophysical parameters (contrast-detail analysis with an automatic reading of CDRAD images). For both scintillation screens the authors accomplished the measurements with four standard beam conditions: RAQ3, RQA5, RQA7, and RQA9.Results: At the Nyquist frequency (3.33 lp/mm) the MTF is about 35% and 25% for CsI and GOS detectors, respectively. The CsI scintillator has better noise properties than the GOS screen in almost all the conditions. This is particularly true for low-energy beams, where the noise for the GOS system can go up to a factor 2 greater than that found for CsI. The DQE of the CsI detector reaches a peak of 60%, 60%, 58%, and 50% for the RQA3, RQA5, RQA7, and RQA9 beams, respectively, whereas for the GOS screen the maximum DQE is 40%, 44%, 44%, and 35%. The contrast-detail analysis confirms that in the majority of cases the CsI scintillator is able to provide improved outcomes to those obtained with the GOS screen.Conclusions: The limited diffusion of light produced by the ISS reading makes possible the achievement of very good spatial resolution. In fact, the MTF of the unit with the CsI panel is only slightly lower to that achieved with direct conversion detectors. The combination of very good spatial resolution, together with the good noise properties reached with the CsI screen, allows achieving DQE on average about 1.5 times greater than that obtained with GOS. In fact, the DQE of unit equipped with CsI is comparable to the best

  3. Digital Mammography Tomosynthesis

    International Nuclear Information System (INIS)

    Gergov, I.; Alexov, G.; Rusonov, K.

    2017-01-01

    Siemens MAMMOMAT Inspiration with Tomosynthesis enhances the diagnostic precision in mammographic screening. The apparatus has a wide-angle tomosynthesis up to 50 degrees. The Siemens breast augmentation algorithm reconstructs multiple two-dimensional breast images into three-dimensional images at the lowest doses to help detect tumors hidden from the overlapping chest tissue, allowing for a more accurate diagnosis than standard 2-dimensional digital mammography, and reducing the number of false positive results. 3D digital tomosynthesis improves the precision of detecting and diagnosing a larger number of expansive lesions, ensures better morphological mass analysis and architectural distortion, and detecting calcifications by adding digital breast tomosynthesis to the traditional two-dimensional digital mammogram of the patient. In this way, it solves the problem of overlapping parenchyma, reduces the number of unnecessary biopsies from questionable sonomammographic findings, and the need for stressful repeating procedures, which usually contributes to both better patient outcomes and cost saving. [bg

  4. Mammographic profiles of women with symptomatic breast diseases ...

    African Journals Online (AJOL)

    Methods: This was a prospective descriptive analytical study of women with symptomatic breast diseases who had mammography between January 2012 and December 2016 at our health facilities. Data sheet was developed to record the patients' biodata, indication for referral, and mammographic findings. Results: During ...

  5. Mammographic and sonographic spectrum of non-puerperal mastitis

    NARCIS (Netherlands)

    M.H. Lequin (Maarten); J. van Spengler (J.); R. van Pel; C.H.J. van Eijck (Casper); H. van Overhagen (H.)

    1995-01-01

    textabstractThe goal of this study was to explore possible specific mammographic and sonographic features in women with non-puerperal mastitis (NPM), in order to make an accurate diagnosis and prevent unnecessary surgical procedures. From a group of 93 patients with NPM diagnosed between 1987 and

  6. Mammographic classification of breast lesions amongst women in ...

    African Journals Online (AJOL)

    Objectives: The study was to classify lesions identified on mammograms using Breast Imaging Reporting and Data System (BIRADS) grading method. This was in view of ascertaining the rate of occurrence of breast malignancy of the studied population. Methods: A retrospective cohort study of 416 mammographic reports of ...

  7. Mucinous carcinoma of the breast: mammographic features with histologic correlation

    International Nuclear Information System (INIS)

    Cui Chunyan; Zhang Ling; Wu Yaopan; Li Shuqin

    2011-01-01

    Objective: To correlate the mammographic findings of mucinous carcinoma with histologic features. Methods: Retrospective analysis of the mammographic and pathologic findings of 37 patients with mucinous carcinomas of the breasts was performed. Results: Mammograms of ten (52.6%) women with mucinous carcinomas showed masses with well-defined, lobu-lated margins correlating well with the pure histologic type. Thirteen (81.3%) mixed type of mucinous carcinomas demonstrated poorly defined or spiculated margins (P<0.05). Most of the pure type carcinomas were hyperdense similar to most of mixed type carcinomas (P<0.05). Of 34 mucinous carcinomas tested, there were 25 ER-positive, 29 PR-positive, 24 C-erbB-2 negative expressions with pure type carcinomas accounting for 78.9%, 89.5% and 78.9%, respectively. Conclusion: The mammographic features of pure type are different from those of mixed type of mucinous breast carcinomas. The most common mammographic appearance of pure mucinous carcinoma is a well-defined mass without calcification whereas the mixed type carcinomas have more aggressive imaging characteristics. (authors)

  8. Mammographic CAD: Correlation of regions in ipsilateral views – a ...

    African Journals Online (AJOL)

    Background. Radiologists analyse both standard mammographic views of a breast to confirm the presence of abnormalities and reduce false-positives. However, at present, no computer-aided diagnosis system uses ipsilateral mammograms to confirm the presence of suspicious features. Aim. The aim of this study was to ...

  9. Mammographer personality traits – elements of the optimal ...

    African Journals Online (AJOL)

    2014-11-07

    Nov 7, 2014 ... competency, good communication skills and the ability to limit patient anxiety and ... personality traits in mammographers in order of importance .... 1 (trust) is high, with a Cronbach's alpha of 0.911 and inter- item reliability ...

  10. Mammographic Findings after Intraoperative Radiotherapy of the Breast

    International Nuclear Information System (INIS)

    Rivera, R.; Holmes, D.R.; Smith-Bronstein, V.S.; Villegas-Mendez, S.; Rayhanabad, J.; Sheth, P.; Rashtian, A.

    2012-01-01

    Intraoperative Radiotherapy (IORT) is a form of accelerated partial breast radiation that has been shown to be equivalent to conventional whole breast external beam radiotherapy (EBRT) in terms of local cancer control. However, questions have been raised about the potential of f IORT to produce breast parenchymal changes that could interfere with mammographic surveillance of cancer recurrence. The purpose of this study was to identify, quantify, and compare the mammographic findings of patients who received IORT and EBRT in a prospective, randomized controlled clinical trial of women with early stage invasive breast cancer undergoing breast conserving therapy between July 2005 and December 2009. Treatment groups were compared with regard to the 1, 2 and 4-year incidence of 6 post-operative mammographic findings: architectural distortion, skin thickening, skin retraction, calcifications, fat necrosis, and mass density. Blinded review of 90 sets of mammograms of 15 IORT and 16 EBRT patients demonstrated a higher incidence of fat necrosis among IORT recipients at years 1, 2, and 4. However, none of the subjects were judged to have suspicious mammogram findings and fat necrosis did not interfere with mammographic interpretation.

  11. Controlled exstirpation of clinically occult but mammographically suspicious findings

    Energy Technology Data Exchange (ETDEWEB)

    Grosse-Vorholt, R

    1981-03-01

    Breast-volume, size and mammographical findings near the chest wall have a great influence on the excision for histological examination. The excision should be done as an controled excision by preoperative marking with a mixture of blue colour and contrast-medium followed by an intraoperative radiography of the exstirpated tissue. We reached in 30 cases a sure excision without any postoperative complications.

  12. Overdiagnosis in mammographic screening for breast cancer in Europe

    DEFF Research Database (Denmark)

    Puliti, Donella; Duffy, Stephen W; Miccinesi, Guido

    2012-01-01

    Overdiagnosis, the detection through screening of a breast cancer that would never have been identified in the lifetime of the woman, is an adverse outcome of screening. We aimed to determine an estimate range for overdiagnosis of breast cancer in European mammographic service screening programmes....

  13. VALIDATION OF THE ASTER GLOBAL DIGITAL ELEVATION MODEL VERSION 2 OVER THE CONTERMINOUS UNITED STATES

    Directory of Open Access Journals (Sweden)

    D. Gesch

    2012-07-01

    Full Text Available The ASTER Global Digital Elevation Model Version 2 (GDEM v2 was evaluated over the conterminous United States in a manner similar to the validation conducted for the original GDEM Version 1 (v1 in 2009. The absolute vertical accuracy of GDEM v2 was calculated by comparison with more than 18,000 independent reference geodetic ground control points from the National Geodetic Survey. The root mean square error (RMSE measured for GDEM v2 is 8.68 meters. This compares with the RMSE of 9.34 meters for GDEM v1. Another important descriptor of vertical accuracy is the mean error, or bias, which indicates if a DEM has an overall vertical offset from true ground level. The GDEM v2 mean error of –0.20 meters is a significant improvement over the GDEM v1 mean error of –3.69 meters. The absolute vertical accuracy assessment results, both mean error and RMSE, were segmented by land cover to examine the effects of cover types on measured errors. The GDEM v2 mean errors by land cover class verify that the presence of aboveground features (tree canopies and built structures cause a positive elevation bias, as would be expected for an imaging system like ASTER. In open ground classes (little or no vegetation with significant aboveground height, GDEM v2 exhibits a negative bias on the order of 1 meter. GDEM v2 was also evaluated by differencing with the Shuttle Radar Topography Mission (SRTM dataset. In many forested areas, GDEM v2 has elevations that are higher in the canopy than SRTM.

  14. Validation of the ASTER Global Digital Elevation Model Version 2 over the conterminous United States

    Science.gov (United States)

    Gesch, Dean B.; Oimoen, Michael J.; Zhang, Zheng; Meyer, David J.; Danielson, Jeffrey J.

    2012-01-01

    The ASTER Global Digital Elevation Model Version 2 (GDEM v2) was evaluated over the conterminous United States in a manner similar to the validation conducted for the original GDEM Version 1 (v1) in 2009. The absolute vertical accuracy of GDEM v2 was calculated by comparison with more than 18,000 independent reference geodetic ground control points from the National Geodetic Survey. The root mean square error (RMSE) measured for GDEM v2 is 8.68 meters. This compares with the RMSE of 9.34 meters for GDEM v1. Another important descriptor of vertical accuracy is the mean error, or bias, which indicates if a DEM has an overall vertical offset from true ground level. The GDEM v2 mean error of -0.20 meters is a significant improvement over the GDEM v1 mean error of -3.69 meters. The absolute vertical accuracy assessment results, both mean error and RMSE, were segmented by land cover to examine the effects of cover types on measured errors. The GDEM v2 mean errors by land cover class verify that the presence of aboveground features (tree canopies and built structures) cause a positive elevation bias, as would be expected for an imaging system like ASTER. In open ground classes (little or no vegetation with significant aboveground height), GDEM v2 exhibits a negative bias on the order of 1 meter. GDEM v2 was also evaluated by differencing with the Shuttle Radar Topography Mission (SRTM) dataset. In many forested areas, GDEM v2 has elevations that are higher in the canopy than SRTM.

  15. COMBINED MAMMOGRAPHIC AND SONOGRAPHIC EVALUATION OF PALPABLE BREAST MASSES

    Directory of Open Access Journals (Sweden)

    Reena Mathur

    2016-10-01

    Full Text Available BACKGROUND Breast diseases are common in females. In developing countries like India, females are unaware of breast pathologies hence they are detected usually in advanced stages. We have studied 100 patients of palpable breast masses presenting to our department and evaluate the role of combined mammographic and sonographic imaging in patients with palpable abnormalities of the breast, which help in decision making by clinician as to lesion go for biopsy or follow up. MATERIALS AND METHODS The study was conducted at Department of Radiodiagnosis J. L.N. Medical College & Associated Groups of Hospitals, Ajmer. We included women equal to or more than 30 years referred to this centre with palpable abnormalities of breast during a period from March 2015 to August 2016. All these women underwent a combined mammographic and sonographic evaluation of breast. RESULTS 50 (50% of the 100 palpable abnormalities had benign assessment, 30 (60% of the benign lesions were visible both on mammography and sonography; 18 (36% of the 50 benign lesions were mammographically occult and identified at sonographic evaluation. 2 lesion was sonographically occult (4% and visualized on mammography. In 14 (14% of the 100 cases, imaging evaluation resulted in a suspicious assessment and all these lesions underwent biopsy and 4 were diagnosed as having malignancy. 36(36% of the 100 palpable abnormalities had negative imaging assessment finding: of these 14 patients underwent biopsy and all had benign findings. The sensitivity and negative predictive value for combined mammographic and sonographic assessment were 100%; the specificity was 78.26%. CONCLUSION Combined use of mammography and sonography plays an important role in the management of palpable breast lesions. It characterizes the palpable mass lesion, avoids unnecessary interventions in which imaging findings are unequivocally benign. Negative findings on combined mammographic and sonographic imaging have very high

  16. EnviroAtlas - Dasymetric Population by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates population by 12-digit HUC. It is based on the EnviroAtlas dasymetric dataset, which intelligently reallocates 2010 population...

  17. EnviroAtlas - Major Grains and Cotton by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the number of major grains grown, yield in tons, and area in hectares for several major grains and for cotton by 12-digit Hydrologic...

  18. EnviroAtlas - Atmospheric Nitrogen Deposition by 12-digit HUC for the Conterminous United States (2006)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset includes annual nitrogen and sulfur deposition within each 12-digit HUC subwatershed for the year 2006. Values are provided for total...

  19. EnviroAtlas - Atmospheric Nitrogen Deposition by 12-digit HUC for the Conterminous United States (2002)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset includes annual nitrogen and sulfur deposition within each 12-digit HUC subwatershed for the year 2002. Values are provided for total...

  20. The application of high voltage digital and analogue unit protections to utility telecommunications systems

    Energy Technology Data Exchange (ETDEWEB)

    Farthing, H. [SNC Group, Montreal, PQ (Canada); Verzosa, Q.R.; Care, J.M. [SNC Group, Montreal, PQ (Canada)

    1996-08-01

    The use of fibre optic and digital microwave systems, both within and without utility communications networks was discussed. Their availability has led to the development of phase comparison and differential current relaying systems which provide enhanced protective features for transmission circuits. The application of fibre optic cable or microwave radio data links overcomes problems caused by ground potential rise and transferred potential damage in metallic pilot wire schemes. Some problems were encountered when installing digital differential current and analogue phase comparison relaying systems to a 220 kV power transmission system where a mix of analog microwave, digital microwave radio and multiplexed fibre optic channels were available. However, the relays were successfully installed with the application of digital pilot differential relays to the power system which enabled fast fault clearance to be achieved. 7 refs., 1 tab., 1 fig.

  1. VALIDATION OF THE ASTER GLOBAL DIGITAL ELEVATION MODEL VERSION 3 OVER THE CONTERMINOUS UNITED STATES

    Directory of Open Access Journals (Sweden)

    D. Gesch

    2016-06-01

    Full Text Available The ASTER Global Digital Elevation Model Version 3 (GDEM v3 was evaluated over the conterminous United States in a manner similar to the validation conducted for the original GDEM Version 1 (v1 in 2009 and GDEM Version 2 (v2 in 2011. The absolute vertical accuracy of GDEM v3 was calculated by comparison with more than 23,000 independent reference geodetic ground control points from the U.S. National Geodetic Survey. The root mean square error (RMSE measured for GDEM v3 is 8.52 meters. This compares with the RMSE of 8.68 meters for GDEM v2. Another important descriptor of vertical accuracy is the mean error, or bias, which indicates if a DEM has an overall vertical offset from true ground level. The GDEM v3 mean error of −1.20 meters reflects an overall negative bias in GDEM v3. The absolute vertical accuracy assessment results, both mean error and RMSE, were segmented by land cover type to provide insight into how GDEM v3 performs in various land surface conditions. While the RMSE varies little across cover types (6.92 to 9.25 meters, the mean error (bias does appear to be affected by land cover type, ranging from −2.99 to +4.16 meters across 14 land cover classes. These results indicate that in areas where built or natural aboveground features are present, GDEM v3 is measuring elevations above the ground level, a condition noted in assessments of previous GDEM versions (v1 and v2 and an expected condition given the type of stereo-optical image data collected by ASTER. GDEM v3 was also evaluated by differencing with the Shuttle Radar Topography Mission (SRTM dataset. In many forested areas, GDEM v3 has elevations that are higher in the canopy than SRTM. The overall validation effort also included an evaluation of the GDEM v3 water mask. In general, the number of distinct water polygons in GDEM v3 is much lower than the number in a reference land cover dataset, but the total areas compare much more closely.

  2. Validation of the ASTER Global Digital Elevation Model version 3 over the conterminous United States

    Science.gov (United States)

    Gesch, Dean B.; Oimoen, Michael J.; Danielson, Jeffrey J.; Meyer, David; Halounova, L; Šafář, V.; Jiang, J.; Olešovská, H.; Dvořáček, P.; Holland, D.; Seredovich, V.A.; Muller, J.P.; Pattabhi Rama Rao, E.; Veenendaal, B.; Mu, L.; Zlatanova, S.; Oberst, J.; Yang, C.P.; Ban, Y.; Stylianidis, S.; Voženílek, V.; Vondráková, A.; Gartner, G.; Remondino, F.; Doytsher, Y.; Percivall, George; Schreier, G.; Dowman, I.; Streilein, A.; Ernst, J.

    2016-01-01

    The ASTER Global Digital Elevation Model Version 3 (GDEM v3) was evaluated over the conterminous United States in a manner similar to the validation conducted for the original GDEM Version 1 (v1) in 2009 and GDEM Version 2 (v2) in 2011. The absolute vertical accuracy of GDEM v3 was calculated by comparison with more than 23,000 independent reference geodetic ground control points from the U.S. National Geodetic Survey. The root mean square error (RMSE) measured for GDEM v3 is 8.52 meters. This compares with the RMSE of 8.68 meters for GDEM v2. Another important descriptor of vertical accuracy is the mean error, or bias, which indicates if a DEM has an overall vertical offset from true ground level. The GDEM v3 mean error of −1.20 meters reflects an overall negative bias in GDEM v3. The absolute vertical accuracy assessment results, both mean error and RMSE, were segmented by land cover type to provide insight into how GDEM v3 performs in various land surface conditions. While the RMSE varies little across cover types (6.92 to 9.25 meters), the mean error (bias) does appear to be affected by land cover type, ranging from −2.99 to +4.16 meters across 14 land cover classes. These results indicate that in areas where built or natural aboveground features are present, GDEM v3 is measuring elevations above the ground level, a condition noted in assessments of previous GDEM versions (v1 and v2) and an expected condition given the type of stereo-optical image data collected by ASTER. GDEM v3 was also evaluated by differencing with the Shuttle Radar Topography Mission (SRTM) dataset. In many forested areas, GDEM v3 has elevations that are higher in the canopy than SRTM. The overall validation effort also included an evaluation of the GDEM v3 water mask. In general, the number of distinct water polygons in GDEM v3 is much lower than the number in a reference land cover dataset, but the total areas compare much more closely.

  3. Analogue to digital upgrade project-boiler feedwater control system for Bruce Power nuclear units 1 & 2

    International Nuclear Information System (INIS)

    Long, R.

    2012-01-01

    Bruce Power Nuclear Generating Station A, “Bruce A” is in the final stages of its Restart Project. This capital project will see a large scale rehabilitation of Units 1 and 2 resulting in addition of 1500MW of safe, reliable, clean electricity to the Ontario grid. Restart Project Scope 375, Boiler Feedwater Controls Upgrade was sanctioned to replace obsolete analog devices with a modern digital control system. This project replaced the existing Foxboro H Line analog controls which comprised of 81 individual control modules and support instrumentation. The replacement system was a Triconex Triple Modular Redundant PLC which interfaces with two redundant touch screen monitors. The upgraded digital system incorporates the following controls: 1. Boiler Level Control Loops 2. Dearator Level Control Loops 3. Dearator Pressure Control Loops 4. Boiler Feedwater Recirculation Flow Control Loops A number of technical challenges were addressed when installing a new digital system within the existing plant configuration. Interfaces to new, old and refurbished field devices must be understood as well as implications of connecting to the plant’s Digital Control Computers (DCC’s) and newly installed Steam Generators. The overall project involved many stakeholders to address various requirements from conceptual / design stage through procurement, construction, commissioning and return to service. In addition, the project highlighted the unique requirements found in Nuclear Industry with respect to Human Factors and Software Quality Assurance. (author)

  4. EnviroAtlas - Average Direct Normal Solar resources kWh/m2/Day by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — The annual average direct normal solar resources by 12-Digit Hydrologic Unit (HUC) was estimated from maps produced by the National Renewable Energy Laboratory for...

  5. EnviroAtlas - Biological nitrogen fixation in natural/semi-natural ecosystems by 12-digit HUC for the Conterminous United States, 2006

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains data on the mean biological nitrogen fixation in natural/semi-natural ecosystems per 12-digit Hydrologic Unit (HUC) in 2006....

  6. EnviroAtlas - Manure application to agricultural lands from confined animal feeding operations by 12-digit HUC for the Conterminous United States, 2006

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains data on the mean livestock manure application to cultivated crop and hay/pasture lands by 12-digit Hydrologic Unit (HUC) in 2006....

  7. Identification of two novel mammographic density loci at 6Q25.1.

    Science.gov (United States)

    Brand, Judith S; Li, Jingmei; Humphreys, Keith; Karlsson, Robert; Eriksson, Mikael; Ivansson, Emma; Hall, Per; Czene, Kamila

    2015-06-03

    Mammographic density (MD) is a strong heritable and intermediate phenotype for breast cancer, but much of its genetic variation remains unexplained. We performed a large-scale genetic association study including 8,419 women of European ancestry to identify MD loci. Participants of three Swedish studies were genotyped on a custom Illumina iSelect genotyping array and percent and absolute mammographic density were ascertained using semiautomated and fully automated methods from film and digital mammograms. Linear regression analysis was used to test for SNP-MD associations, adjusting for age, body mass index, menopausal status and six principal components. Meta-analyses were performed by combining P values taking sample size, study-specific inflation factor and direction of effect into account. Genome-wide significant associations were observed for two previously identified loci: ZNF365 (rs10995194, P = 2.3 × 10(-8) for percent MD and P = 8.7 × 10(-9) for absolute MD) and AREG (rs10034692, P = 6.7 × 10(-9) for absolute MD). In addition, we found evidence of association for two variants at 6q25.1, both of which are known breast cancer susceptibility loci: rs9485370 in the TAB2 gene (P = 4.8 × 10(-9) for percent MD and P = 2.5 × 10(-8) for absolute MD) and rs60705924 in the CCDC170/ESR1 region (P = 2.2 × 10(-8) for absolute MD). Both regions have been implicated in estrogen receptor signaling with TAB2 being a potential regulator of tamoxifen response. We identified two novel MD loci at 6q25.1. These findings underscore the importance of 6q25.1 as a susceptibility region and provide more insight into the mechanisms through which MD influences breast cancer risk.

  8. Body mass index and participation in organized mammographic screening

    DEFF Research Database (Denmark)

    Hellmann, Sophie Sell; Njor, Sisse Helle; Lynge, Elsebeth

    2015-01-01

    BACKGROUND: Breast cancer is the leading cancer among women, and early diagnosis is essential for future prognosis. Evidence from mainly cross-sectional US studies with self-reported exposure and outcome found positive association of body mass index (BMI) with non-participation in mammographic...... with normal weight. This association was limited to postmenopausal women (Wald test p = 0.08), with enhanced non-participation in underweight (2.83: 1.52-5.27) and obese women of class II and III (1.84: 1.15-2.95; 2.47: 1.20-5.06) as compared to normal weight postmenopausal women. There was no effect...... modification by HT, previous screening participation, or morbidities, besides suggestive evidence of enhanced non-participation in diabetic overweight and obese women. CONCLUSIONS: Underweight and very obese postmenopausal women were significantly less likely to participate in mammographic screening than women...

  9. Mammographic and sonographic features of fat necrosis of the breast

    International Nuclear Information System (INIS)

    Upadhyaya, Vidya S; Uppoor, Raghuraj; Shetty, Lathika

    2013-01-01

    Imaging features of fat necrosis vary depending on its stage of evolution and can mimic malignancy in late stages. Imaging may suffice to differentiate fat necrosis in the early stages from malignancy and thus avoid unnecessary biopsy. In this pictorial essay, we present combination of benign features in mammography and/or ultrasonography (USG) that can lead to imaging diagnosis of fat necrosis. The follow-up imaging features of fat necrosis which mirror its pathophysiological evolution have also been demonstrated. To summarize, in the appropriate clinical setting, no mammographic features suspicious for malignancy should be present. When the typical mammographic features are not present, USG can aid with the diagnosis and follow up USG can confirm it

  10. Mammographic screening practices among Chinese-Australian women.

    Science.gov (United States)

    Kwok, Cannas; Fethney, Judith; White, Kate

    2012-03-01

    To report mammographic screening practice among Chinese-Australian women, and to examine the relationship between demographic characteristics, acculturation factors (English proficiency and length of stay in Australia), cultural beliefs, and having a mammogram as recommended. Cross-sectional and descriptive. The study was conducted in 2009 in Sydney, Australia. Of 988 Chinese-Australian women over 18 years of age invited to participate in the study, 785 (79%) completed and returned the questionnaire. Of these women, 320 (40.8%) were in the target age range of 50 to 69 years. The Chinese Breast Cancer Screening Beliefs Questionnaire (CBCSB) was used as a data collection instrument. Analysis included descriptive statistics, bivariate analysis using chi-square and t tests, and logistic regression. Of the 320 women in the targeted age range of 50 to 69 years, 238 (74.4%) had a mammogram as recommended biannually. Being married-de facto, in the 60 to 69 age group, and speaking Cantonese at home were positively associated with women's mammographic screening practice. However, no statistically significant differences in acculturation factors and having a mammogram as recommended were found. In terms of CBCSB score, women who had mammograms as recommended had more positive attitudes toward health checkups and perceived fewer barriers to mammographic screening. Effort should be focused on specific subgroups of Chinese-Australian women in order to fully understand the barriers involved in participating in mammographic screening. Nurses can use the findings from the present study to design culturally sensitive breast cancer screening programs to encourage women's participation in mammography. © 2011 Sigma Theta Tau International.

  11. Application of Digital Technology for the Plant Protection System in Ulchin Nuclear Power Plant Units 5 and 6

    International Nuclear Information System (INIS)

    Deucksoo, Lee; Insik, Kim

    2006-01-01

    Since the completion of construction of Ulchin Nuclear Power Plant Units 3 and 4 (UCN 3 and 4), the first units of the OPR (Optimized Power Reactor) series, various advanced design features have been incorporated to the following OPRs. The Ulchin Nuclear Power Plant Units 5 and 6(UCN 5 and 6) which started commercial operation in Korea from 2004 and 2005 respectively, are designed to provide improvements in safety, reliability and costs by applying both advanced proven technology and experiences gained from the construction and operation of the previous OPRs. Among those improvements, the digital plant protection system (DPPS) and the digital engineered safety feature actuation system (DESFAS) are the key elements to the UCN 5 and 6 designs. The DPPS and DESFAS utilizing the digital computer technology offer a solution to the obsolescence problem of analog system. These features also provide the potential for additional benefits such as ease of maintenance, increased performance, reduction of internal and external cross channel wiring, improvement of the surveillance testability and flexibility of control logic programming change. During the initial design stage, the Korean regulatory body had evaluated these design concepts intensively and concluded it to be acceptable for the safety point of view. Also, in-depth review on the detailed design and the special evaluation/audit for the software design process has been performed to secure the quality of the software. As a result, every issue raised during licensing review has been clarified and the operating licenses for the UCN 5 and 6 were issued in October, 2003 and October, 2004 respectively, by the government. In this paper, design characteristics of the UCN 5 and 6 are introduced, and advanced design features and implementation process are presented focused on the DPPS/DESFAS with some benefit analysis results. (authors)

  12. Preserving Long-Term Access to United States Government Documents in Legacy Digital Formats

    Science.gov (United States)

    Woods, Kam A.

    2010-01-01

    Over the past several decades, millions of digital objects of significant scientific, economic, cultural, and historic value have been published and distributed to libraries and archives on removable media. Providing long-term access to these documents, media files, and software executables is an increasingly complex task because of dependencies…

  13. Mammographic density measurements are not affected by mammography system.

    Science.gov (United States)

    Damases, Christine N; Brennan, Patrick C; McEntee, Mark F

    2015-01-01

    Mammographic density (MD) is a significant risk factor for breast cancer and has been shown to reduce the sensitivity of mammography screening. Knowledge of a woman's density can be used to predict her risk of developing breast cancer and personalize her imaging pathway. However, measurement of breast density has proven to be troublesome with wide variations in density recorded using radiologists' visual Breast Imaging Reporting and Data System (BIRADS). Several automated methods for assessing breast density have been proposed, each with their own source of measurement error. The use of differing mammographic imaging systems further complicates MD measurement, especially for the same women imaged over time. The purpose of this study was to investigate whether having a mammogram on differing manufacturer's equipment affects a woman's MD measurement. Raw mammographic images were acquired on two mammography imaging systems (General Electric and Hologic) one year apart and processed using VolparaDensity™ to obtain the Volpara Density Grade (VDG) and average volumetric breast density percentage (AvBD%). Visual BIRADS scores were also obtained from 20 expert readers. BIRADS scores for both systems showed strong positive correlation ([Formula: see text]; [Formula: see text]), while the VDG ([Formula: see text]; [Formula: see text]) and AvBD% ([Formula: see text]; [Formula: see text]) showed stronger positive correlations. Substantial agreement was shown between the systems for BIRADS ([Formula: see text]; [Formula: see text]), however, the systems demonstrated an almost perfect agreement for VDG ([Formula: see text]; [Formula: see text]).

  14. The clinical and mammographic features of plasma cell mastitis

    International Nuclear Information System (INIS)

    Wu Xiurong; Luo Xiaohua; Yu Xuming; Zhong Shan; Huang Yufan; Wu Xinyi; Lin Yubin

    2007-01-01

    Objective: To investigate the clinical and mammographic features of plasma cell mastitis. Methods: Twenty-five patients (28 lesions) with histologically confirmed plasma cell mastitis, aged from 26 to 70 years (mean age 41 years), were examined with X-ray mammography. The clinical manifestations and imaging features were retrospectively reviewed. Results: No case was in lactation. The painful irregular masses, ranged from 1.3 to 8cm in size, were found in 22 patients, while 3 patients with acute episode. Recurrent episodes of breast masses were noted in 4 patients. Based on the mammographic appearances, the plasma cell mastitis were classified as the following four types: inflammation-like type (2/28), ductal ectasia type (3/28), focal infiltration type (10/28) and nodular type (13/28). The valuable radiographic signs: (1) An asymmetrically increased density along the lactiferous duct with a flame-like appearance, inhomogeneous low density tubular structures and scattered stick-shape calcifications. (2) Architectural distortion and oil cysts formation in adjacent area, (3) Subareolar ductal ectasia. Conclusions: The clinical and mammographic characteristics of plasma cell mastitis are critical to avoiding unnecessary surgery. Histopathological result is needed for the diagnosis in patients highly suspected of malignancy. (authors)

  15. Identification of simulated microcalcifications in white noise and mammographic backgrounds

    International Nuclear Information System (INIS)

    Reiser, Ingrid; Nishikawa, Robert M.

    2006-01-01

    This work investigates human performance in discriminating between differently shaped simulated microcalcifications embedded in white noise or mammographic backgrounds. Human performance was determined through two alternative forced-choice (2-AFC) experiments. The signals used were computer-generated simple shapes that were designed such that they had equal signal energy. This assured equal detectability. For experiments involving mammographic backgrounds, signals were blurred to account for the imaging system modulation transfer function (MTF). White noise backgrounds were computer generated; anatomic background patches were extracted from normal mammograms. We compared human performance levels as a function of signal energy in the expected difference template. In the discrimination task, the expected difference template is the difference between the two signals shown. In white noise backgrounds, human performance in the discrimination task was degraded compared to the detection task. In mammographic backgrounds, human performance in the discrimination task exceeded that of the detection task. This indicates that human observers do not follow the optimum decision strategy of correlating the expected signal template with the image. Human observer performance was qualitatively reproduced by non-prewhitening with eye filter (NPWE) model observer calculations, in which spatial uncertainty was explicitly included by shifting the locations of the expected difference templates. The results indicate that human strategy in the discrimination task may be to match individual signal templates with the image individually, rather than to perform template matching between the expected difference template and the image

  16. Invasive ductal carcinoma vs. invasive lobular carcinoma; mammographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Chun; Do, Young Soo; Oh, Hoon Il; Han, Yoon Hee; Kim, Ki Soo; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-01-01

    The purpose of this study is to evaluate mammographic findings of invasive ductal carcinoma (IDC) and invasive lobular carcinoma(ILC) and to find differential points between the two. 239 patients, who underwent mammography prior to surgery and were proved to have IDC(patients) or ILC(15 patients) pathologically, were analized retrospectively. On mammogram, presence of mass and microcalcification were analized. When there was a mass on mammogram, lesion opacity was classified into high, equal, or low opacity and border of the mass was classified into spiculated, poorly marginated, and well-marginated. When there was no definite mass, mammographic findings were classifie into asymmetric opacity and no mass. Masses were observed in 168 patients(75%) of IDC and 12 patients(80%) of ILC. Border of the masses were spiculated(n=50, 22.3%), poorly marginated(n=112, 50%), or well-marginated(n=6, 2.7%) in patients with IDC. Spiculated and poorly marginated borders were observed in 8 patients(53.3%) and 4 patients(26.7%) respectively, in patients with ILC. Microcalcifications were seen in 88 patients(17.3%) of IDC and patients(33.3%) of ILC. Although equal or low opacities were observed more frequently in ILC and microcalcifications were noted more frequently in IDC, it was difficult to differentiate the two diseases based on mammographic findings.

  17. Invasive ductal carcinoma vs. invasive lobular carcinoma; mammographic findings

    International Nuclear Information System (INIS)

    Lee, Eun Chun; Do, Young Soo; Oh, Hoon Il; Han, Yoon Hee; Kim, Ki Soo; Chin, Soo Yil

    1996-01-01

    The purpose of this study is to evaluate mammographic findings of invasive ductal carcinoma (IDC) and invasive lobular carcinoma(ILC) and to find differential points between the two. 239 patients, who underwent mammography prior to surgery and were proved to have IDC(patients) or ILC(15 patients) pathologically, were analized retrospectively. On mammogram, presence of mass and microcalcification were analized. When there was a mass on mammogram, lesion opacity was classified into high, equal, or low opacity and border of the mass was classified into spiculated, poorly marginated, and well-marginated. When there was no definite mass, mammographic findings were classifie into asymmetric opacity and no mass. Masses were observed in 168 patients(75%) of IDC and 12 patients(80%) of ILC. Border of the masses were spiculated(n=50, 22.3%), poorly marginated(n=112, 50%), or well-marginated(n=6, 2.7%) in patients with IDC. Spiculated and poorly marginated borders were observed in 8 patients(53.3%) and 4 patients(26.7%) respectively, in patients with ILC. Microcalcifications were seen in 88 patients(17.3%) of IDC and patients(33.3%) of ILC. Although equal or low opacities were observed more frequently in ILC and microcalcifications were noted more frequently in IDC, it was difficult to differentiate the two diseases based on mammographic findings

  18. Early detection of the incidence of malignancy in mammograms using digital image correlation

    International Nuclear Information System (INIS)

    Espitia, J.; Jacome, J.; Torres, C.

    2016-01-01

    The digital image correlation has proved an effective way for Pattern Recognition, this research to identify the using Findings digitally extracted from a mammographic image, which is the means used by more specialists to determine if a person is a candidate or not, a Suffer Breast Cancer. This shown that early detection of symptom logy 'carcinogenic' is the key . (Author)

  19. The virtual digital nuclear power plant: A modern tool for supporting the lifecycle of VVER-based nuclear power units

    Science.gov (United States)

    Arkadov, G. V.; Zhukavin, A. P.; Kroshilin, A. E.; Parshikov, I. A.; Solov'ev, S. L.; Shishov, A. V.

    2014-10-01

    The article describes the "Virtual Digital VVER-Based Nuclear Power Plant" computerized system comprising a totality of verified initial data (sets of input data for a model intended for describing the behavior of nuclear power plant (NPP) systems in design and emergency modes of their operation) and a unified system of new-generation computation codes intended for carrying out coordinated computation of the variety of physical processes in the reactor core and NPP equipment. Experiments with the demonstration version of the "Virtual Digital VVER-Based NPP" computerized system has shown that it is in principle possible to set up a unified system of computation codes in a common software environment for carrying out interconnected calculations of various physical phenomena at NPPs constructed according to the standard AES-2006 project. With the full-scale version of the "Virtual Digital VVER-Based NPP" computerized system put in operation, the concerned engineering, design, construction, and operating organizations will have access to all necessary information relating to the NPP power unit project throughout its entire lifecycle. The domestically developed commercial-grade software product set to operate as an independently operating application to the project will bring about additional competitive advantages in the modern market of nuclear power technologies.

  20. Fast electronics and digital selection units in the spectrometers of the Laboratory of Neutron Physics

    International Nuclear Information System (INIS)

    Bogdzel', A.A.; Tishin, V.G.; Fo Dyk Toan.

    1984-01-01

    Fast amplifier, two types, discriminator coincidence multiplicity coding unit, perialised crate controller for multi analysis with external buffer memory are described. The specifications black diagrams of the units are presented. The multidetector system for γ-radiation multiplicity measurements are also described

  1. False-positive results in mammographic screening for breast cancer in Europe

    DEFF Research Database (Denmark)

    Hofvind, Solveig; Ponti, Antonio; Patnick, Julietta

    2012-01-01

    To estimate the cumulative risk of a false-positive screening result in European mammographic screening programmes, and examine the rates and procedures of further assessment.......To estimate the cumulative risk of a false-positive screening result in European mammographic screening programmes, and examine the rates and procedures of further assessment....

  2. The impact of mammographic screening on breast cancer mortality in Europe

    DEFF Research Database (Denmark)

    Broeders, Mireille; Moss, Sue; Nyström, Lennarth

    2012-01-01

    To assess the impact of population-based mammographic screening on breast cancer mortality in Europe, considering different methodologies and limitations of the data.......To assess the impact of population-based mammographic screening on breast cancer mortality in Europe, considering different methodologies and limitations of the data....

  3. Old shovels with digital control technology retrofits give new units a run for their money

    Energy Technology Data Exchange (ETDEWEB)

    Duskey, M.R. [Avtron Manufacturing Inc., Cleveland, OH (United States)

    2006-04-15

    New digital drive control systems can be retrofitted to shovels and draglines to maximize their performance and keep them running smoothly and reliably. Case histories of successful retrofits are reported. The static drives on a Marion 310 DC drive shovel operating in British Columbia were replaced with Avtron Firing Modules to improve machine availability. Three old Bucyrus 295 M-G set-controlled shovels operated by mines in North Dakota and Labrador which were experiencing excessive downtime were replaced with an Avtron ADD-32DMG field regulator. 2 figs.

  4. EnviroAtlas - Agricultural Water Demand by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national agricultural water demand metric provides insight into the amount of water currently used for agricultural irrigation in the contiguous United States....

  5. Spatial recurrence analysis: A sensitive and fast detection tool in digital mammography

    International Nuclear Information System (INIS)

    Prado, T. L.; Galuzio, P. P.; Lopes, S. R.; Viana, R. L.

    2014-01-01

    Efficient diagnostics of breast cancer requires fast digital mammographic image processing. Many breast lesions, both benign and malignant, are barely visible to the untrained eye and requires accurate and reliable methods of image processing. We propose a new method of digital mammographic image analysis that meets both needs. It uses the concept of spatial recurrence as the basis of a spatial recurrence quantification analysis, which is the spatial extension of the well-known time recurrence analysis. The recurrence-based quantifiers are able to evidence breast lesions in a way as good as the best standard image processing methods available, but with a better control over the spurious fragments in the image

  6. From a mammographic station to a federal mammalogic center

    International Nuclear Information System (INIS)

    Rozhkova, N.I.; Kharchenko, V.P.

    2000-01-01

    Using the history of mammalogy development in Russian Scientific Center of Roentgenoradiology of the Ministry of Public Health of Russian Federation as an example the evolution of above trend in Russia is retraced. It is shown that during 20 years (from 1978) in the department of mammary gland diseases diagnosis of the Centre the rational, economically expedient and highly efficient diagnostic system for combined examination of mammary glands is developing and introducing in medical prophylactic installations of Russian Federation. This system consists of women selection for risk group, stage of additional examination in special mammographic rooms and therapeutic stage. Directions of researches of the Centre (technical, organizational-methodical, medical) are considered [ru

  7. Classification of mammographic masses using geometric symmetry and fractal analysis

    Energy Technology Data Exchange (ETDEWEB)

    Guo Qi; Ruiz, V.F. [Cybernetics, School of Systems Engineering, Univ. of Reading (United Kingdom); Shao Jiaqing [Dept. of Electronics, Univ. of Kent (United Kingdom); Guo Falei [WanDe Industrial Engineering Co. (China)

    2007-06-15

    In this paper, we propose a fuzzy symmetry measure based on geometrical operations to characterise shape irregularity of mammographic mass lesion. Group theory, a powerful tool in the investigation of geometric transformation, is employed in our work to define and describe the underlying mathematical relations. We investigate the usefulness of fuzzy symmetry measure in combination with fractal analysis for classification of masses. Comparative studies show that fuzzy symmetry measure is useful for shape characterisation of mass lesions and is a good complementary feature for benign-versus-malignant classification of masses. (orig.)

  8. Barriers and facillitators to compliance with routine mammographic screening

    International Nuclear Information System (INIS)

    Kessler, H.B.; Rimer, B.; Keintz, M.K.; Myers, R.E.; Engstrom, P.F.

    1988-01-01

    Six hundred one randomly selected women were interviewed to determine their reasons for compliance or noncompliance with free HMO-sponsored mammographic examinations. Noncompliers were significantly more likely to believe mammograms are unnecessary without symptoms, too much trouble, or inconvenient and to perceive their physicians as not recommending mammograms. Compliers were more likely to believe that early breast cancer can be cured and to recognize that breast screening is for asymptomatic individuals. When cost is eliminated as a barrier to screening, a variety of socioeconomic, psychological, and access barriers are exposed. Radiologists must be cognizant of these factors in planning and participating in breast cancer screening programs

  9. Mammographic follow-up after conservation therapy for breast cancer

    International Nuclear Information System (INIS)

    Gu Yajia; Xiao Qin; Zheng Xiaojing; Wu Jiong; Chen Jiayi; Gu Rongfeng; Feng Xiaoyuan

    2006-01-01

    Objective: To recognize the mammographic changes after conservation therapy for breast carcinoma. Methods: A total of 139 follow-up mammographic examinations in 85 cases were studied during the period between 1999 and 2004. Mammography was performed at intervals of 6 months for the first 2 years, then annually. Attention was paid to mammographic change patterns of conservation therapy for breast carcinoma, including breast edema, skin thickening, architectural disturbance, asymmetric density, architectural distortion retraction, and calcifications. SPSS version 11.0 for windows was used to perform all statistical tests. Kruskal-Wallis H test was used for calculating the overall statistical differences between difference periods. Categorical data were expressed as percentages and analyzed by using the X 2 test. The age of the patients ranged from 25 to 63 years (mediate, 44 years old). The time of follow-up observation ranged from 1 week to 72 months. Results: Two cases were normal on mammograms. High proportion of abnormal mammography was seen in the period of 12 month (40.3%, 56/139) and 24 month (21.6%, 30/139), respectively. Various findings appeared in various periods and the difference was statistically significant(X 2 =30.998, v=6, P=0.001). Mild edema appeared in the first 3 years. Moderately severe or marked breast edema may be present between 6 months to 12 months, then slowly resolved. The appearance and disappearance of skin thickening were similar to the process of breast edema. The changes of architectural disturbance did not correlate with time (X 2 =8.634, P>0.05), but on sequential mammograms for same patient, the extent of architectural disturbance relieved over time (17/19). Asymmetric density was found in only 5 patients, and disappeared in later period of follow-up in 3. Architectural distortion retraction got more and more obvious with time, and kept stable after certain period of time. Calcifications were shown in 2 patients, including 1

  10. Towards an automatic tool for resolution evaluation of mammographic images

    Energy Technology Data Exchange (ETDEWEB)

    De Oliveira, J. E. E. [FUMEC, Av. Alfonso Pena 3880, CEP 30130-009 Belo Horizonte - MG (Brazil); Nogueira, M. S., E-mail: juliae@fumec.br [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Pte. Antonio Carlos 6627, 31270-901, Belo Horizonte - MG (Brazil)

    2014-08-15

    Medical images are important for diagnosis purposes as they are related to patients medical history and pathology. Breast cancer represents a leading cause of death among women worldwide, and its early detection is the most effective method of reducing mortality. In a way to identify small structures with low density differences, a high image quality is required with the use of low doses of radiation. The analysis of the quality of the obtained image from a mammogram is performed from an image of a simulated breast and this is a fundamental key point for a program of quality control of mammography equipment s. In a control program of mammographic equipment s, besides the analysis of the quality of mammographic images, each element of the chain which composes the formation of the image is also analyzed: X-rays equipment s, radiographic films, and operating conditions. This control allows that an effective and efficient exam can be provided to the population and is within the standards of quality required for the early detection of breast cancer. However, according to the State Program of Quality Control in Mammography of Minas Gerais, Brazil, only 40% of the mammographies have provided a simulated image with a minimum level of quality, thus reinforcing the need for monitoring the images. The reduction of the morbidity and mortality indexes, with optimization and assurance of access to diagnosis and breast cancer treatment in the state of Minas Gerais, Brazil, may be the result of a mammographic exam which has a final image with good quality and which automatic evaluation is not subjective. The reason is that one has to consider the hypothesis that humans are subjective when performing the image analysis and that the evaluation of the image can be executed by a computer with objectivity. In 2007, in order to maintain the standard quality needed to mammography, the State Health Secretariat of Minas Gerais, Brazil, established a Program of Monthly Monitoring the

  11. Towards an automatic tool for resolution evaluation of mammographic images

    International Nuclear Information System (INIS)

    De Oliveira, J. E. E.; Nogueira, M. S.

    2014-08-01

    Medical images are important for diagnosis purposes as they are related to patients medical history and pathology. Breast cancer represents a leading cause of death among women worldwide, and its early detection is the most effective method of reducing mortality. In a way to identify small structures with low density differences, a high image quality is required with the use of low doses of radiation. The analysis of the quality of the obtained image from a mammogram is performed from an image of a simulated breast and this is a fundamental key point for a program of quality control of mammography equipment s. In a control program of mammographic equipment s, besides the analysis of the quality of mammographic images, each element of the chain which composes the formation of the image is also analyzed: X-rays equipment s, radiographic films, and operating conditions. This control allows that an effective and efficient exam can be provided to the population and is within the standards of quality required for the early detection of breast cancer. However, according to the State Program of Quality Control in Mammography of Minas Gerais, Brazil, only 40% of the mammographies have provided a simulated image with a minimum level of quality, thus reinforcing the need for monitoring the images. The reduction of the morbidity and mortality indexes, with optimization and assurance of access to diagnosis and breast cancer treatment in the state of Minas Gerais, Brazil, may be the result of a mammographic exam which has a final image with good quality and which automatic evaluation is not subjective. The reason is that one has to consider the hypothesis that humans are subjective when performing the image analysis and that the evaluation of the image can be executed by a computer with objectivity. In 2007, in order to maintain the standard quality needed to mammography, the State Health Secretariat of Minas Gerais, Brazil, established a Program of Monthly Monitoring the

  12. A new digital ground-fault protection system for generator-transformer unit

    Energy Technology Data Exchange (ETDEWEB)

    Zielichowski, Mieczyslaw; Szlezak, Tomasz [Institute of Electrical Power Engineering, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50370 Wroclaw (Poland)

    2007-08-15

    Ground faults are one of most often reasons of damages in stator windings of large generators. Under certain conditions, as a result of ground-fault protection systems maloperation, ground faults convert into high-current faults, causing severe failures in power system. Numerous publications in renowned journals and magazines testify about ground-fault matter importance and problems reported by exploitators confirm opinions, that some issues concerning ground-fault protection of large generators have not been solved yet or have been solved insufficiently. In this paper a new conception of a digital ground-fault protection system for stator winding of large generator was proposed. The process of intermittent arc ground fault in stator winding has been briefly discussed and actual ground-fault voltage waveforms were presented. A new relaying algorithm, based on third harmonic voltage measurement was also drawn and the methods of its implementation and testing were described. (author)

  13. Common input to motor units of intrinsic and extrinsic hand muscles during two-digit object hold.

    Science.gov (United States)

    Winges, Sara A; Kornatz, Kurt W; Santello, Marco

    2008-03-01

    Anatomical and physiological evidence suggests that common input to motor neurons of hand muscles is an important neural mechanism for hand control. To gain insight into the synaptic input underlying the coordination of hand muscles, significant effort has been devoted to describing the distribution of common input across motor units of extrinsic muscles. Much less is known, however, about the distribution of common input to motor units belonging to different intrinsic muscles and to intrinsic-extrinsic muscle pairs. To address this void in the literature, we quantified the incidence and strength of near-simultaneous discharges of motor units residing in either the same or different intrinsic hand muscles (m. first dorsal, FDI, and m. first palmar interosseus, FPI) during two-digit object hold. To extend the characterization of common input to pairs of extrinsic muscles (previous work) and pairs of intrinsic muscles (present work), we also recorded electromyographic (EMG) activity from an extrinsic thumb muscle (m. flexor pollicis longus, FPL). Motor-unit synchrony across FDI and FPI was weak (common input strength, CIS, mean +/- SE: 0.17 +/- 0.02). Similarly, motor units from extrinsic-intrinsic muscle pairs were characterized by weak synchrony (FPL-FDI: 0.25 +/- 0.02; FPL-FPI: 0.29 +/- 0.03) although stronger than FDI-FPI. Last, CIS from within FDI and FPI was more than three times stronger (0.70 +/- 0.06 and 0.66 +/- 0.06, respectively) than across these muscles. We discuss present and previous findings within the framework of muscle-pair specific distribution of common input to hand muscles based on their functional role in grasping.

  14. A study on the optimal replacement periods of digital control computer's components of Wolsung nuclear power plant unit 1

    International Nuclear Information System (INIS)

    Mok, Jin Il; Seong, Poong Hyun

    1993-01-01

    Due to the failure of the instrument and control devices of nuclear power plants caused by aging, nuclear power plants occasionally trip. Even a trip of a single nuclear power plant (NPP) causes an extravagant economical loss and deteriorates public acceptance of nuclear power plants. Therefore, the replacement of the instrument and control devices with proper consideration of the aging effect is necessary in order to prevent the inadvertent trip. In this paper we investigated the optimal replacement periods of the control computer's components of Wolsung nuclear power plant Unit 1. We first derived mathematical models of optimal replacement periods to the digital control computer's components of Wolsung NPP Unit 1 and calculated the optimal replacement periods analytically. We compared the periods with the replacement periods currently used at Wolsung NPP Unit 1. The periods used at Wolsung is not based on mathematical analysis, but on empirical knowledge. As a consequence, the optimal replacement periods analytically obtained and those used in the field show a little difference. (Author)

  15. EnviroAtlas - Big Game Hunting Recreation Demand by 12-Digit HUC in the Conterminous United States

    Science.gov (United States)

    This EnviroAtlas dataset includes the total number of recreational days per year demanded by people ages 18 and over for big game hunting by location in the contiguous United States. Big game includes deer, elk, bear, and wild turkey. These values are based on 2010 population distribution, 2011 U.S. Fish and Wildlife Service (FWS) Fish, Hunting, and Wildlife-Associated Recreation (FHWAR) survey data, and 2011 U.S. Department of Agriculture (USDA) Forest Service National Visitor Use Monitoring program data, and have been summarized by 12-digit hydrologic unit code (HUC). This dataset was produced by the US EPA to support research and online mapping activities related to the EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

  16. Evaluasi Tingkat Kesiapan Organisasi dalam Rangka Preservasi Digital (Studi Kasus Pada Unit Repositori Flinders Academic Commons Of Flinders University Library (FACFUL, Adelaide, Australia Selatan

    Directory of Open Access Journals (Sweden)

    Rattahpinnusa Haresariu Handisa

    2017-12-01

    Full Text Available Penelitian ini bertujuan mengidentifikasi tingkat kesiapan lembaga repositori dalam rangka preservasi digital pada Flinders Academic Commons Flinders University Library (FACFUL dan mengidentifikasi faktor-faktor yang berpengaruh terhadap tingkat kesiapan organisasi. Terdapat tiga aspek yang diteliti meliputi: kesiapan infrastruktur, kesiapan teknologi serta sumber daya yang dibutuhkan bagi preservasi digital. Penelitian ini menggunakan metode studi kasus dengan  intesity sampel. Adapun instrumen pengumpulan data menggunakan Cornell University Survey of Institutional Readiness Checklist. Selanjutnya, tehnik pengambilan data menggunakan tehnik wawancara dengan Ms. Liz-Walkley Hall selaku pustakawati yang bertanggung jawab terhadap unit repositori digital FACFUL. Adapun informasi penunjang diperoleh melalui studi kepustakaan merujuk pada website Perpustakaan Universitas  Flinders. Data yang terkumpul dianalisis secara deskriptif menggunakan indikator kesiapan organisasi Cornel University Model. Hasil penelitian menunjukkan bahwa unit repositori pada FACFUL kurang siap dalam menjalankan preservasi digital. Tingkat kesiapan organisasi Perpustakaan Universitas  Flinders dalam pelestarian digital berapa pada level terbawah yakni Acknowledgement . Pada tingkat tersebut, Perpustakaan Flinders masih dalam tahap pengembangan kesadaran tentang pentingnya preservasi digital. Selanjutnya, faktor-faktor yang mempengaruhi rendahnya tingkat kesiapan organisasi tersebut adalah tidak adanya pernyataan pentingya preservasi digital pada kebijakan pengembangan koleksi; keterbatasan pendanaan dan keterbatasan sumber daya manusia yang kompeten dalam preservasi digital. Penelitian ini merekomendasikan Perpustakaan Universitas Flinders untuk  melakukan uji kelayakan bagi preservasi digital. Salah satu model bisnis yang sesuai dengan kondisi Perpustakaan Universitas  Flinders adalah Meta Archive Model (MAM. Model tersebut berbasis komunitas bagi preservasi digital

  17. Computerized analysis of mammographic parenchymal patterns for assessing breast cancer risk: Effect of ROI size and location

    International Nuclear Information System (INIS)

    Li Hui; Giger, Maryellen L.; Huo Zhimin; Olopade, Olufunmilayo I.; Lan Li; Weber, Barbara L.; Bonta, Ioana

    2004-01-01

    The long-term goal of our research is to develop computerized radiographic markers for assessing breast density and parenchymal patterns that may be used together with clinical measures for determining the risk of breast cancer and assessing the response to preventive treatment. In our earlier studies, we found that women at high risk tended to have dense breasts with mammographic patterns that were coarse and low in contrast. With our method, computerized texture analysis is performed on a region of interest (ROI) within the mammographic image. In our current study, we investigate the effect of ROI size and ROI location on the computerized texture features obtained from 90 subjects (30 BRCA1/BRCA2 gene-mutation carriers and 60 age-matched women deemed to be at low risk for breast cancer). Mammograms were digitized at 0.1 mm pixel size and various ROI sizes were extracted from different breast regions in the craniocaudal (CC) view. Seventeen features, which characterize the density and texture of the parenchymal patterns, were extracted from the ROIs on these digitized mammograms. Stepwise feature selection and linear discriminant analysis were applied to identify features that differentiate between the low-risk women and the BRCA1/BRCA2 gene-mutation carriers. ROC analysis was used to assess the performance of the features in the task of distinguishing between these two groups. Our results show that there was a statistically significant decrease in the performance of the computerized texture features, as the ROI location was varied from the central region behind the nipple. However, we failed to show a statistically significant decrease in the performance of the computerized texture features with decreasing ROI size for the range studied

  18. Positive predictive values by mammographic density and screening mode in the Norwegian Breast Cancer Screening Program.

    Science.gov (United States)

    Moshina, Nataliia; Ursin, Giske; Roman, Marta; Sebuødegård, Sofie; Hofvind, Solveig

    2016-01-01

    To investigate the probability of breast cancer among women recalled due to abnormal findings on the screening mammograms (PPV-1) and among women who underwent an invasive procedure (PPV-2) by mammographic density (MD), screening mode and age. We used information about 28,826 recall examinations from 26,951 subsequently screened women in the Norwegian Breast Cancer Screening Program, 1996-2010. The radiologists who performed the recall examinations subjectively classified MD on the mammograms into three categories: fatty (70%). Screening mode was defined as screen-film mammography (SFM) and full-field digital mammography (FFDM). We examined trends of PPVs by MD, screening mode and age. We used logistic regression to estimate odds ratio (OR) of screen-detected breast cancer associated with MD among women recalled, adjusting for screening mode and age. PPV-1 and PPV-2 decreased by increasing MD, regardless of screening mode (p for trend breasts. Among women recalled, the adjusted OR of breast cancer decreased with increasing MD. Compared with women with fatty breasts, the OR was 0.90 (95% CI: 0.84-0.96) for those with medium dense breasts and 0.85 (95% CI: 0.76-0.95) for those with dense breasts. PPVs decreased by increasing MD. Fewer women needed to be recalled or undergo an invasive procedure to detect one breast cancer among those with fatty versus dense breasts in the screening program in Norway, 1996-2010. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. CADx of mammographic masses and clustered microcalcifications: A review

    International Nuclear Information System (INIS)

    Elter, Matthias; Horsch, Alexander

    2009-01-01

    Breast cancer is the most common type of cancer among women in the western world. While mammography is regarded as the most effective tool for the detection and diagnosis of breast cancer, the interpretation of mammograms is a difficult and error-prone task. Hence, computer aids have been developed that assist the radiologist in the interpretation of mammograms. Computer-aided detection (CADe) systems address the problem that radiologists often miss signs of cancers that are retrospectively visible in mammograms. Furthermore, computer-aided diagnosis (CADx) systems have been proposed that assist the radiologist in the classification of mammographic lesions as benign or malignant. While a broad variety of approaches to both CADe and CADx systems have been published in the past two decades, an extensive survey of the state of the art is only available for CADe approaches. Therefore, a comprehensive review of the state of the art of CADx approaches is presented in this work. Besides providing a summary, the goals for this article are to identify relations, contradictions, and gaps in literature, and to suggest directions for future research. Because of the vast amount of publications on the topic, this survey is restricted to the two most important types of mammographic lesions: masses and clustered microcalcifications. Furthermore, it focuses on articles published in international journals.

  20. CADx of mammographic masses and clustered microcalcifications: A review

    Energy Technology Data Exchange (ETDEWEB)

    Elter, Matthias; Horsch, Alexander [Fraunhofer Institute for Integrated Circuits (IIS), Am Wolfsmantel 33, 91058 Erlangen (Germany); Institute for Medical Statistics and Epidemiology, TU Muenchen, Ismaninger Strasse 22, 81675 Muenchen (Germany) and Department of Computer Science, University of Tromsoe Breivika, N-9037 Tromsoe (Norway)

    2009-06-15

    Breast cancer is the most common type of cancer among women in the western world. While mammography is regarded as the most effective tool for the detection and diagnosis of breast cancer, the interpretation of mammograms is a difficult and error-prone task. Hence, computer aids have been developed that assist the radiologist in the interpretation of mammograms. Computer-aided detection (CADe) systems address the problem that radiologists often miss signs of cancers that are retrospectively visible in mammograms. Furthermore, computer-aided diagnosis (CADx) systems have been proposed that assist the radiologist in the classification of mammographic lesions as benign or malignant. While a broad variety of approaches to both CADe and CADx systems have been published in the past two decades, an extensive survey of the state of the art is only available for CADe approaches. Therefore, a comprehensive review of the state of the art of CADx approaches is presented in this work. Besides providing a summary, the goals for this article are to identify relations, contradictions, and gaps in literature, and to suggest directions for future research. Because of the vast amount of publications on the topic, this survey is restricted to the two most important types of mammographic lesions: masses and clustered microcalcifications. Furthermore, it focuses on articles published in international journals.

  1. Feature extraction from mammographic images using fast marching methods

    International Nuclear Information System (INIS)

    Bottigli, U.; Golosio, B.

    2002-01-01

    Features extraction from medical images represents a fundamental step for shape recognition and diagnostic support. The present work faces the problem of the detection of large features, such as massive lesions and organ contours, from mammographic images. The regions of interest are often characterized by an average grayness intensity that is different from the surrounding. In most cases, however, the desired features cannot be extracted by simple gray level thresholding, because of image noise and non-uniform density of the surrounding tissue. In this work, edge detection is achieved through the fast marching method (Level Set Methods and Fast Marching Methods, Cambridge University Press, Cambridge, 1999), which is based on the theory of interface evolution. Starting from a seed point in the shape of interest, a front is generated which evolves according to an appropriate speed function. Such function is expressed in terms of geometric properties of the evolving interface and of image properties, and should become zero when the front reaches the desired boundary. Some examples of application of such method to mammographic images from the CALMA database (Nucl. Instr. and Meth. A 460 (2001) 107) are presented here and discussed

  2. Benefit-risk evaluation of mammographic mass screening

    International Nuclear Information System (INIS)

    Sato, Nobuo; Ogura, Toshihiro

    1990-01-01

    This study evaluated the benefit-risk balance of mammography in mass screening by using survival rates from 3000 breast cancer patients at the Japanese Foundation for Cancer Research Institute Hospital. Because the number of participants in mammographic mass screening was small, asymptomatic patients with pathologically proven early breast cancer were categorized as the screenee group. Symptomatic patients were categorized as the patient group. Survival rates were compared in both the screenee and the patient groups. Based on the difference in areas of survival curves between screenees and patients, the ratio of person-year gain (PYG) to person-year lost (PYL) was obtained. The ratio of PYG to PYL was multiplied by the detection rate resulting from a particular screening program to obtain the benefit/risk ratio. The detection rate of nonpalpable breast cancer was 15 times higher in the screenee group than the patient group. Breast cancer was detected in 7 (0.85%) of 824 patients in the screenee group. Even when mammographic mass screening was started at the age of 30, the benefit of mammography was far superior to the risk. The number of participants in mass screening stratified by age may be required for the conclusion of the benefit-risk balance of mammography in mass screening. (N.K.)

  3. Serum osteoprotegerin levels and mammographic density among high-risk women.

    Science.gov (United States)

    Moran, Olivia; Zaman, Tasnim; Eisen, Andrea; Demsky, Rochelle; Blackmore, Kristina; Knight, Julia A; Elser, Christine; Ginsburg, Ophira; Zbuk, Kevin; Yaffe, Martin; Narod, Steven A; Salmena, Leonardo; Kotsopoulos, Joanne

    2018-06-01

    Mammographic density is a risk factor for breast cancer but the mechanism behind this association is unclear. The receptor activator of nuclear factor κB (RANK)/RANK ligand (RANKL) pathway has been implicated in the development of breast cancer. Given the role of RANK signaling in mammary epithelial cell proliferation, we hypothesized this pathway may also be associated with mammographic density. Osteoprotegerin (OPG), a decoy receptor for RANKL, is known to inhibit RANK signaling. Thus, it is of interest to evaluate whether OPG levels modify breast cancer risk through mammographic density. We quantified serum OPG levels in 57 premenopausal and 43 postmenopausal women using an enzyme-linked immunosorbent assay (ELISA). Cumulus was used to measure percent density, dense area, and non-dense area for each mammographic image. Subjects were classified into high versus low OPG levels based on the median serum OPG level in the entire cohort (115.1 pg/mL). Multivariate models were used to assess the relationship between serum OPG levels and the measures of mammographic density. Serum OPG levels were not associated with mammographic density among premenopausal women (P ≥ 0.42). Among postmenopausal women, those with low serum OPG levels had higher mean percent mammographic density (20.9% vs. 13.7%; P = 0.04) and mean dense area (23.4 cm 2 vs. 15.2 cm 2 ; P = 0.02) compared to those with high serum OPG levels after covariate adjustment. These findings suggest that low OPG levels may be associated with high mammographic density, particularly in postmenopausal women. Targeting RANK signaling may represent a plausible, non-surgical prevention option for high-risk women with high mammographic density, especially those with low circulating OPG levels.

  4. Closed-loop control for cardiopulmonary management and intensive care unit sedation using digital imaging

    Science.gov (United States)

    Gholami, Behnood

    This dissertation introduces a new problem in the delivery of healthcare, which could result in lower cost and a higher quality of medical care as compared to the current healthcare practice. In particular, a framework is developed for sedation and cardiopulmonary management for patients in the intensive care unit. A method is introduced to automatically detect pain and agitation in nonverbal patients, specifically in sedated patients in the intensive care unit, using their facial expressions. Furthermore, deterministic as well as probabilistic expert systems are developed to suggest the appropriate drug dose based on patient sedation level. Patients in the intensive care unit who require mechanical ventilation due to acute respiratory failure also frequently require the administration of sedative agents. The need for sedation arises both from patient anxiety due to the loss of personal control and the unfamiliar and intrusive environment of the intensive care unit, and also due to pain or other variants of noxious stimuli. In this dissertation, we develop a rule-based expert system for cardiopulmonary management and intensive care unit sedation. Furthermore, we use probability theory to quantify uncertainty and to extend the proposed rule-based expert system to deal with more realistic situations. Pain assessment in patients who are unable to verbally communicate is a challenging problem. The fundamental limitations in pain assessment stem from subjective assessment criteria, rather than quantifiable, measurable data. The relevance vector machine (RVM) classification technique is a Bayesian extension of the support vector machine (SVM) algorithm which achieves comparable performance to SVM while providing posterior probabilities for class memberships and a sparser model. In this dissertation, we use the RVM classification technique to distinguish pain from non-pain as well as assess pain intensity levels. We also correlate our results with the pain intensity

  5. Collaborating with Mammographers to Address Their Work-Related Musculoskeletal Discomfort

    Science.gov (United States)

    Sommerich, Carolyn M.; Lavender, Steven A.; Evans, Kevin D.; Sanders, Elizabeth; Joines, Sharon; Lamar, Sabrina; Umar, Radin Zaid Radin; Yen, Wei-Ting; Park, SangHyun

    2017-01-01

    Mammographers are an understudied group of healthcare workers, yet the prevalence of musculoskeletal (MSK) symptoms in mammographers appears to be elevated, similar to many occupations in healthcare. In this study, we used a participatory approach to identify needs and opportunities for developing interventions to reduce mammographers’ exposures to risk factors that lead to development of MSK symptoms. In this paper, we present a number of those needs and several intervention concepts along with evaluations of those concepts from experienced mammographers. We include findings from a preliminary field test of a novel intervention concept to reduce the need to adopt awkward postures while positioning patients for a screening or diagnostic mammogram. PMID:26794257

  6. Digital Radiology Image Learning Library

    International Nuclear Information System (INIS)

    Arenson, R.L.; Greenes, R.; Allman, R.; Swett, H.

    1989-01-01

    The Digital Radiology Image Learning Library (DRILL) is designed as an interactive teaching tool targeted to the radiologic community. The DRILL pilot comprises a comprehensive mammographic information base consisting of factual data in a relational database, an extensive knowledge base in semantic nets and high-resolution images. A flexible query module permits the user to browse and retrieve examination data, case discussions, and related images. Other applications, including expert systems, instructional programs, and skill building exercises, can be accessed through well-defined software constructs

  7. Microscopy system of atomic force based on a digital optical reading unit and a buzzer-scanner

    International Nuclear Information System (INIS)

    Dabirian, R.; Loza M, D.; Wang, W. M.; Hwu, E. T.

    2015-01-01

    An astigmatic detection system (Ads) based on a compact disk/digital-versatile-disk (Cd-DVD) astigmatic optical pickup unit is presented. It can achieve a resolution better than 0.3 nm in detection of the vertical displacement and is able to detect the two-dimensional angular tilt of the object surface. Furthermore, a novel scanner design actuated by piezoelectric disk buzzers is presented. The scanner is composed of a quad-rod actuation structure and several piezoelectric disks. It can be driven directly with low-voltage and low-current sources, such as analogue outputs of a data acquisition card and enables a sufficient scanning range of up to μm. In addition, an economic, high-performance streamlined atomic force microscopy (AFM) was constructed, using the buzzer-scanner to move the sample relative to the probe, and using a Cd/DVD optical pickup unit to detect the mechanical resonance of a micro fabricated cantilever. The performance of the AFM is evaluated. The high sensitivity and high bandwidth of the detection system makes the equipment suitable for characterizing nano scale elements. An AFM using our detection system for detecting the deflection of micro fabricated cantilevers can resolve individual atomic steps on graphite surfaces. (Author)

  8. Readiness for Delivering Digital Health at Scale: Lessons From a Longitudinal Qualitative Evaluation of a National Digital Health Innovation Program in the United Kingdom

    Science.gov (United States)

    Lennon, Marilyn R; Bouamrane, Matt-Mouley; Devlin, Alison M; O'Connor, Siobhan; O'Donnell, Catherine; Chetty, Ula; Agbakoba, Ruth; Bikker, Annemieke; Grieve, Eleanor; Finch, Tracy; Watson, Nicholas; Wyke, Sally

    2017-01-01

    Background Digital health has the potential to support care delivery for chronic illness. Despite positive evidence from localized implementations, new technologies have proven slow to become accepted, integrated, and routinized at scale. Objective The aim of our study was to examine barriers and facilitators to implementation of digital health at scale through the evaluation of a £37m national digital health program: ‟Delivering Assisted Living Lifestyles at Scale” (dallas) from 2012-2015. Methods The study was a longitudinal qualitative, multi-stakeholder, implementation study. The methods included interviews (n=125) with key implementers, focus groups with consumers and patients (n=7), project meetings (n=12), field work or observation in the communities (n=16), health professional survey responses (n=48), and cross program documentary evidence on implementation (n=215). We used a sociological theory called normalization process theory (NPT) and a longitudinal (3 years) qualitative framework analysis approach. This work did not study a single intervention or population. Instead, we evaluated the processes (of designing and delivering digital health), and our outcomes were the identified barriers and facilitators to delivering and mainstreaming services and products within the mixed sector digital health ecosystem. Results We identified three main levels of issues influencing readiness for digital health: macro (market, infrastructure, policy), meso (organizational), and micro (professional or public). Factors hindering implementation included: lack of information technology (IT) infrastructure, uncertainty around information governance, lack of incentives to prioritize interoperability, lack of precedence on accountability within the commercial sector, and a market perceived as difficult to navigate. Factors enabling implementation were: clinical endorsement, champions who promoted digital health, and public and professional willingness. Conclusions

  9. Readiness for Delivering Digital Health at Scale: Lessons From a Longitudinal Qualitative Evaluation of a National Digital Health Innovation Program in the United Kingdom.

    Science.gov (United States)

    Lennon, Marilyn R; Bouamrane, Matt-Mouley; Devlin, Alison M; O'Connor, Siobhan; O'Donnell, Catherine; Chetty, Ula; Agbakoba, Ruth; Bikker, Annemieke; Grieve, Eleanor; Finch, Tracy; Watson, Nicholas; Wyke, Sally; Mair, Frances S

    2017-02-16

    Digital health has the potential to support care delivery for chronic illness. Despite positive evidence from localized implementations, new technologies have proven slow to become accepted, integrated, and routinized at scale. The aim of our study was to examine barriers and facilitators to implementation of digital health at scale through the evaluation of a £37m national digital health program: ‟Delivering Assisted Living Lifestyles at Scale" (dallas) from 2012-2015. The study was a longitudinal qualitative, multi-stakeholder, implementation study. The methods included interviews (n=125) with key implementers, focus groups with consumers and patients (n=7), project meetings (n=12), field work or observation in the communities (n=16), health professional survey responses (n=48), and cross program documentary evidence on implementation (n=215). We used a sociological theory called normalization process theory (NPT) and a longitudinal (3 years) qualitative framework analysis approach. This work did not study a single intervention or population. Instead, we evaluated the processes (of designing and delivering digital health), and our outcomes were the identified barriers and facilitators to delivering and mainstreaming services and products within the mixed sector digital health ecosystem. We identified three main levels of issues influencing readiness for digital health: macro (market, infrastructure, policy), meso (organizational), and micro (professional or public). Factors hindering implementation included: lack of information technology (IT) infrastructure, uncertainty around information governance, lack of incentives to prioritize interoperability, lack of precedence on accountability within the commercial sector, and a market perceived as difficult to navigate. Factors enabling implementation were: clinical endorsement, champions who promoted digital health, and public and professional willingness. Although there is receptiveness to digital health

  10. Practical Testing and Performance Analysis of Phasor Measurement Unit Using Real Time Digital Simulator (RTDS)

    DEFF Research Database (Denmark)

    Liu, Leo; Rather, Zakir Hussain; Stearn, Nathen

    2012-01-01

    Wide Area Measurement Systems (WAMS) and Wide Area Monitoring, Protection and Control Systems (WAMPACS) have evolved rapidly over the last two decades [1]. This fast emerging technology enables real time synchronized monitoring of power systems. Presently, WAMS are mainly used for real time...... visualisation and post event analysis of power systems. It is expected however, that through integration with traditional Supervisory Control and Data Acquisition (SCADA) systems, closed loop control applications will be possible. Phasor Measurement Units (PMUs) are fundamental components of WAMS. Large WAMS...... proposed to realize highly precise phasoreasurements. Further a comparative study based on features of PMUs from different major manufacturers is presented. The selection of optimal parameters, such as phasor format and filter length is also discussed for various applications....

  11. A new clinical unit for digital radiography based on a thick amorphous Selenium plate: Physical and psychophysical characterization

    International Nuclear Information System (INIS)

    Rivetti, Stefano; Lanconelli, Nico; Bertolini, Marco; Acchiappati, Domenico

    2011-01-01

    Purpose: Here, we present a physical and psychophysical characterization of a new clinical unit (named AcSelerate) for digital radiography based on a thick a-Se layer. We also compared images acquired with and without a software filter (named CRF) developed for reducing sharpness and noise of the images and making them similar to images coming from traditional computed radiography systems. Methods: The characterization was achieved in terms of physical figures of merit [modulation transfer function (MTF), noise power spectra (NPS), detective quantum efficiency (DQE)], and psychophysical parameters (contrast-detail analysis with an automatic reading of CDRAD images). We accomplished measurements with four standard beam conditions: RAQ3, RQA5, RQA7, and RQA9. Results: The system shows an excellent MTF (about 50% at the Nyquist frequency). The DQE is about 55% at 0.5 lp/mm and above 20% at the Nyquist frequency and is almost independent from exposure. The contrast-detail curves are comparable to some of the best published data for other systems devoted to imaging in general radiography. The CRF filter influences both the MTF and NPS, but it does lead to very small changes on DQE. Also the visibility of CDRAD details is basically unaltered, when the filter is activated. Conclusions: As normally happens with detector based on direct conversion, the system presents an excellent MTF. The improved efficiency caused by the thick layer allows getting good noise characteristics and DQE results better (about 10% on average) than many of the computed radiography (CR) systems and comparable to those obtained by the best systems for digital radiography available on the market.

  12. 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)

  13. Evaluation of mammographic density patterns: reproducibility and concordance among scales

    Directory of Open Access Journals (Sweden)

    Garrido-Estepa Macarena

    2010-09-01

    Full Text Available Abstract Background Increased mammographic breast density is a moderate risk factor for breast cancer. Different scales have been proposed for classifying mammographic density. This study sought to assess intra-rater agreement for the most widely used scales (Wolfe, Tabár, BI-RADS and Boyd and compare them in terms of classifying mammograms as high- or low-density. Methods The study covered 3572 mammograms drawn from women included in the DDM-Spain study, carried-out in seven Spanish Autonomous Regions. Each mammogram was read by an expert radiologist and classified using the Wolfe, Tabár, BI-RADS and Boyd scales. In addition, 375 mammograms randomly selected were read a second time to estimate intra-rater agreement for each scale using the kappa statistic. Owing to the ordinal nature of the scales, weighted kappa was computed. The entire set of mammograms (3572 was used to calculate agreement among the different scales in classifying high/low-density patterns, with the kappa statistic being computed on a pair-wise basis. High density was defined as follows: percentage of dense tissue greater than 50% for the Boyd, "heterogeneously dense and extremely dense" categories for the BI-RADS, categories P2 and DY for the Wolfe, and categories IV and V for the Tabár scales. Results There was good agreement between the first and second reading, with weighted kappa values of 0.84 for Wolfe, 0.71 for Tabár, 0.90 for BI-RADS, and 0.92 for Boyd scale. Furthermore, there was substantial agreement among the different scales in classifying high- versus low-density patterns. Agreement was almost perfect between the quantitative scales, Boyd and BI-RADS, and good for those based on the observed pattern, i.e., Tabár and Wolfe (kappa 0.81. Agreement was lower when comparing a pattern-based (Wolfe or Tabár versus a quantitative-based (BI-RADS or Boyd scale. Moreover, the Wolfe and Tabár scales classified more mammograms in the high-risk group, 46.61 and 37

  14. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2000-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  15. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2001-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  16. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    1999-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  17. Demonstration Project on Mammographic Computer-Aided Diagnosis for Breast Cancer Detection

    National Research Council Canada - National Science Library

    Doi, Kunio

    2002-01-01

    ...) in mammographic detection of breast cancer. Our plan is to develop advanced CAD schemes for detection and characterization of clustered microcalcifications and masses by incorporating artificial neural networks and various image processing techniques...

  18. Comparison of Danish dichotomous and BI-RADS classifications of mammographic density

    DEFF Research Database (Denmark)

    Hodge, Rebecca; Hellmann, Sophie Sell; von Euler-Chelpin, My

    2014-01-01

    BACKGROUND: In the Copenhagen mammography screening program from 1991 to 2001, mammographic density was classified either as fatty or mixed/dense. This dichotomous mammographic density classification system is unique internationally, and has not been validated before. PURPOSE: To compare the Danish...... dichotomous mammographic density classification system from 1991 to 2001 with the density BI-RADS classifications, in an attempt to validate the Danish classification system. MATERIAL AND METHODS: The study sample consisted of 120 mammograms taken in Copenhagen in 1991-2001, which tested false positive......, and which were in 2012 re-assessed and classified according to the BI-RADS classification system. We calculated inter-rater agreement between the Danish dichotomous mammographic classification as fatty or mixed/dense and the four-level BI-RADS classification by the linear weighted Kappa statistic. RESULTS...

  19. TU-FG-209-08: Distribution of the Deviation Index (DI) in Digital Radiography Practices Across the United States

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A; Shepard, S [UT MD Anderson Cancer Center, Houston, TX (United States); Dave, J [Thomas Jefferson University, Philadelphia, PA (United States); Fisher, R [The Cleveland Clinic, Cleveland, OH (United States); Hulme, K [The Cleveland Clinic, Beachwood, OH (United States); Rill, L [University Florida, Jacksonville Beach, FL (United States); Zamora, D [University of Washington, Seattle, WA (United States); Woodward, A [The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Brady, S [St. Jude Children’s Research Hospital, Memphis, TN (United States); MacDougall, R [Children’s Hospital, Boston, MA (United States); Goldman, L [Hartford Hospital, Hartford, CT (United States); Lang, S; Peck, D [Henry Ford Health System, Detroit, MI (United States); Apgar, B [AGFA HealthCare, Greenville, SC (United States); Uzenoff, R [FUJIFILM Medical Systems U.S.A., Inc., Weston, CT (United States); Willis, C [University of Texas MD Anderson Cancer Center, Bellaire, TX (United States)

    2016-06-15

    Purpose: To characterize the distribution of the deviation index (DI) in digital radiography practices across the United States. Methods: DI data was obtained from 10 collaborating institutions in the United States between 2012 and 2015. Each institution complied with the requirements of the Institutional Review Board at their site. DI data from radiographs of the body parts chest, abdomen, pelvis and extremity were analyzed for anteroposterior, posteroanterior, lateral, and decubitus views. The DI data was analyzed both in aggregate and stratified by exposure control method, image receptor technology, patient age, and participating site for each body part and view. The number of exposures with DI falling within previously published control limits for DI and descriptive statistics were calculated. Results: DI data from 505,930 radiographic exposures was analyzed. The number of exposures with DI falling within published control limits for DI varied from 10 to 20% for adult patients and 10 to 23% for pediatric patients for different body parts and views. Mean DI values averaged over other parameters for radiographs of the abdomen, chest, pelvis, and extremities ranged from 0.3 to 1.0, −0.6 to 0.5, 0.8, and −0.9 to 0.5 for the different adult views and ranged from −1.6 to −0.1, −0.3 to 0.5, −0.1, −0.2 to 1.4 for the different pediatric views, respectively (DI data was solicited only for anteroposterior view of pelvis). Standard deviation values of DI from individual sites ranged from 1.3 to 3.6 and 1.3 to 3.0 for the different adult and pediatric views, respectively. Also of interest was that target exposure indicators varied by up to a factor of 6 between sites for certain body parts and views. Conclusion: Previously published DI control limits do not reflect the state of clinical practice in digital radiography. Mean DI and target exposure indicators are targets for quality improvement efforts in radiography.

  20. TU-FG-209-08: Distribution of the Deviation Index (DI) in Digital Radiography Practices Across the United States

    International Nuclear Information System (INIS)

    Jones, A; Shepard, S; Dave, J; Fisher, R; Hulme, K; Rill, L; Zamora, D; Woodward, A; Brady, S; MacDougall, R; Goldman, L; Lang, S; Peck, D; Apgar, B; Uzenoff, R; Willis, C

    2016-01-01

    Purpose: To characterize the distribution of the deviation index (DI) in digital radiography practices across the United States. Methods: DI data was obtained from 10 collaborating institutions in the United States between 2012 and 2015. Each institution complied with the requirements of the Institutional Review Board at their site. DI data from radiographs of the body parts chest, abdomen, pelvis and extremity were analyzed for anteroposterior, posteroanterior, lateral, and decubitus views. The DI data was analyzed both in aggregate and stratified by exposure control method, image receptor technology, patient age, and participating site for each body part and view. The number of exposures with DI falling within previously published control limits for DI and descriptive statistics were calculated. Results: DI data from 505,930 radiographic exposures was analyzed. The number of exposures with DI falling within published control limits for DI varied from 10 to 20% for adult patients and 10 to 23% for pediatric patients for different body parts and views. Mean DI values averaged over other parameters for radiographs of the abdomen, chest, pelvis, and extremities ranged from 0.3 to 1.0, −0.6 to 0.5, 0.8, and −0.9 to 0.5 for the different adult views and ranged from −1.6 to −0.1, −0.3 to 0.5, −0.1, −0.2 to 1.4 for the different pediatric views, respectively (DI data was solicited only for anteroposterior view of pelvis). Standard deviation values of DI from individual sites ranged from 1.3 to 3.6 and 1.3 to 3.0 for the different adult and pediatric views, respectively. Also of interest was that target exposure indicators varied by up to a factor of 6 between sites for certain body parts and views. Conclusion: Previously published DI control limits do not reflect the state of clinical practice in digital radiography. Mean DI and target exposure indicators are targets for quality improvement efforts in radiography.

  1. Digital breast tomosynthesis; Digitale Tomosynthese der Brust

    Energy Technology Data Exchange (ETDEWEB)

    Haegele, Julian; Barkhausen, Joerg [Universtiaetsklinikum Schleswig-Holstein, Luebeck (Germany). Klinik fuer Radiologie und Nuklearmedizin; Pursche, Telja [Universtiaetsklinikum Schleswig-Holstein, Luebeck (Germany). Brustzentrum; Schaefer, Fritz K.W. [Universtiaetsklinikum Schleswig-Holstein, Kiel (Germany). Bereich Mammadiagnostik und Intervention

    2015-09-15

    In digital breast tomosynthesis a digital tomographic data set with a very high spatial resolution is reconstructed from low-dose projections collected over a limited rotation angle. This allows a very detailed assessment of e. g. masses and architectural distortions. The average glandular dose is comparable to 2 D mammography. First clinical studies demonstrated that tomosynthesis is able to supply important additional information in suspicious mammographic findings. In comparison to projection mammography, tomosynthesis shows an at least comparable diagnostic accuracy. In everyday practice, tomosynthesis is currently mostly used for further evaluation of suspicious findings in mammography.

  2. Investigation of support vector machine for the detection of architectural distortion in mammographic images

    International Nuclear Information System (INIS)

    Guo, Q; Shao, J; Ruiz, V

    2005-01-01

    This paper investigates detection of architectural distortion in mammographic images using support vector machine. Hausdorff dimension is used to characterise the texture feature of mammographic images. Support vector machine, a learning machine based on statistical learning theory, is trained through supervised learning to detect architectural distortion. Compared to the Radial Basis Function neural networks, SVM produced more accurate classification results in distinguishing architectural distortion abnormality from normal breast parenchyma

  3. Investigation of support vector machine for the detection of architectural distortion in mammographic images

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Q [Department of Cybernetics, University of Reading, Reading RG6 6AY (United Kingdom); Shao, J [Department of Electronics, University of Kent at Canterbury, Kent CT2 7NT (United Kingdom); Ruiz, V [Department of Cybernetics, University of Reading, Reading RG6 6AY (United Kingdom)

    2005-01-01

    This paper investigates detection of architectural distortion in mammographic images using support vector machine. Hausdorff dimension is used to characterise the texture feature of mammographic images. Support vector machine, a learning machine based on statistical learning theory, is trained through supervised learning to detect architectural distortion. Compared to the Radial Basis Function neural networks, SVM produced more accurate classification results in distinguishing architectural distortion abnormality from normal breast parenchyma.

  4. Comparison of Danish dichotomous and BI-RADS classifications of mammographic density.

    Science.gov (United States)

    Hodge, Rebecca; Hellmann, Sophie Sell; von Euler-Chelpin, My; Vejborg, Ilse; Andersen, Zorana Jovanovic

    2014-06-01

    In the Copenhagen mammography screening program from 1991 to 2001, mammographic density was classified either as fatty or mixed/dense. This dichotomous mammographic density classification system is unique internationally, and has not been validated before. To compare the Danish dichotomous mammographic density classification system from 1991 to 2001 with the density BI-RADS classifications, in an attempt to validate the Danish classification system. The study sample consisted of 120 mammograms taken in Copenhagen in 1991-2001, which tested false positive, and which were in 2012 re-assessed and classified according to the BI-RADS classification system. We calculated inter-rater agreement between the Danish dichotomous mammographic classification as fatty or mixed/dense and the four-level BI-RADS classification by the linear weighted Kappa statistic. Of the 120 women, 32 (26.7%) were classified as having fatty and 88 (73.3%) as mixed/dense mammographic density, according to Danish dichotomous classification. According to BI-RADS density classification, 12 (10.0%) women were classified as having predominantly fatty (BI-RADS code 1), 46 (38.3%) as having scattered fibroglandular (BI-RADS code 2), 57 (47.5%) as having heterogeneously dense (BI-RADS 3), and five (4.2%) as having extremely dense (BI-RADS code 4) mammographic density. The inter-rater variability assessed by weighted kappa statistic showed a substantial agreement (0.75). The dichotomous mammographic density classification system utilized in early years of Copenhagen's mammographic screening program (1991-2001) agreed well with the BI-RADS density classification system.

  5. Novel Associations between Common Breast Cancer Susceptibility Variants and Risk-Predicting Mammographic Density Measures

    OpenAIRE

    Stone, Jennifer; Thompson, Deborah J.; dos-Santos-Silva, Isabel; Scott, Christopher; Tamimi, Rulla M.; Lindstrom, Sara; Kraft, Peter; Hazra, Aditi; Li, Jingmei; Eriksson, Louise; Czene, Kamila; Hall, Per; Jensen, Matt; Cunningham, Julie; Olson, Janet E.

    2015-01-01

    Mammographic density measures adjusted for age and body mass index (BMI) are heritable predictors of breast cancer risk but few mammographic density-associated genetic variants have been identified. Using data for 10,727 women from two international consortia, we estimated associations between 77 common breast cancer susceptibility variants and absolute dense area, percent dense area and absolute non-dense area adjusted for study, age and BMI using mixed linear modeling. We found strong suppo...

  6. The impact of mammographic screening on breast cancer mortality in Europe

    DEFF Research Database (Denmark)

    Moss, S M; Nyström, L; Jonsson, H.

    2012-01-01

    Analysing trends in population breast cancer mortality statistics appears a simple method of estimating the effectiveness of mammographic screening programmes. We reviewed such studies of population-based screening in Europe to assess their value.......Analysing trends in population breast cancer mortality statistics appears a simple method of estimating the effectiveness of mammographic screening programmes. We reviewed such studies of population-based screening in Europe to assess their value....

  7. Evaluation of mammographic screen-film combinations in the clinic

    International Nuclear Information System (INIS)

    Shepard, J.

    1987-01-01

    Six commercially available mammographic film-screen combinations were evaluated in the authors department. Film speed and contrast was measured by obtaining H and D curves. Sensitivity to processing conditions was determined by analyzing changes in the H and D cures as a function of development time and temperature and by examining artifacts in a uniformly exposed film. Radiographs of a 0.5 0 star pattern show relative screen unsharpness. The speed of the film-screen combination is indicated by calculating patient dose necessary to produce optical densities of 1.5 through phantom thicknesses of 3.5 cm of acrylic. Images of a modified RMI detail phantom obtained with each film-screen combination were evaluated by 22 radiologist. Results indicate the physicians' overall preference

  8. Decision aids for improved accuracy and standardization of mammographic diagnosis

    International Nuclear Information System (INIS)

    D'Orsi, C.J.; Getty, D.J.; Swets, J.A.; Pickett, R.M.; Seltzer, S.E.; McNeil, B.J.

    1990-01-01

    This paper examines the gains in the accuracy of mammographic diagnosis of breast cancer achievable from a pair of decision aids. Twenty-three potentially relevant perceptual features of mammograms were identified through interviews, psychometric tests, and consensus meetings with mammography specialists. Statistical analyses determined the 12 independent features that were most information diagnostically and assigned a weight to each according to its importance. Two decision aids were developed: a checklist that solicits a scale value from the radiologist for each feature and a computer program that merges those values optimally in an advisory estimate of the probability of malignancy. Six radiologists read a set of 150 cases, first in their usual way and later with the aids

  9. 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.

  10. Male breast disease: clinical, mammographic, and ultrasonographic features

    International Nuclear Information System (INIS)

    Guenhan-Bilgen, Isil; Bozkaya, Halil; Uestuen, Esin Emin; Memis, Aysenur

    2002-01-01

    Purpose: To describe and quantitate the radiological (mammographic and ultrasonographic) characteristics of male breast disease and to report the clinical and pathological findings. Materials and methods: Two-hundred-thirty-six male patients with different male breast diseases, diagnosed at our institution between January 1990 and July 2001, were retrospectively evaluated. The history, physical examination, mammographic and ultrasonographic findings were analyzed. Results: The spectrum of the disease in 236 male patients were gynecomastia (n=206), primary breast carcinoma (n=14), fat necrosis (n=5), lipoma (n=3), subareolar abscess (n=2), epidermal inclusion cyst (n=1), sebaceous cyst (n=1), hematoma (n=1), myeloma (n=1), and metastatic carcinoma (n=2). The distribution of patterns of gynecomastia were; 34% (n=71) nodular, 35% (n=73) dendritic and 31% (n=62) diffuse glandular. Gynecomastia was unilateral in 55% (n=113) and bilateral in 45% (n=93) of the patients. Male breast cancer presented as a mass without microcalcifications in 86% (n=12) and with microcalcifications in 7% (n=1) of patients. The mass was obscured by gynecomastia, partially in two, totally in one patient. The location of the mass was retroareolar in 46% (n=6) and eccentric to the nipple in 54% (n=7) of patients. On ultrasonography (US), the contours were well-circumscribed in 20% (n=3) and irregular in 80% (n=12) of the masses. Conclusion: Male breast has a wide spectrum of diseases, some of which have characteristic radiological appearances that can be correlated with their pathologic diagnosis. In the evaluation of the male breast, mammography and US are essential and should be performed along with physical examination

  11. Male breast disease: clinical, mammographic, and ultrasonographic features

    Energy Technology Data Exchange (ETDEWEB)

    Guenhan-Bilgen, Isil E-mail: isilbilgen@hotmail.com; Bozkaya, Halil; Uestuen, Esin Emin; Memis, Aysenur

    2002-09-01

    Purpose: To describe and quantitate the radiological (mammographic and ultrasonographic) characteristics of male breast disease and to report the clinical and pathological findings. Materials and methods: Two-hundred-thirty-six male patients with different male breast diseases, diagnosed at our institution between January 1990 and July 2001, were retrospectively evaluated. The history, physical examination, mammographic and ultrasonographic findings were analyzed. Results: The spectrum of the disease in 236 male patients were gynecomastia (n=206), primary breast carcinoma (n=14), fat necrosis (n=5), lipoma (n=3), subareolar abscess (n=2), epidermal inclusion cyst (n=1), sebaceous cyst (n=1), hematoma (n=1), myeloma (n=1), and metastatic carcinoma (n=2). The distribution of patterns of gynecomastia were; 34% (n=71) nodular, 35% (n=73) dendritic and 31% (n=62) diffuse glandular. Gynecomastia was unilateral in 55% (n=113) and bilateral in 45% (n=93) of the patients. Male breast cancer presented as a mass without microcalcifications in 86% (n=12) and with microcalcifications in 7% (n=1) of patients. The mass was obscured by gynecomastia, partially in two, totally in one patient. The location of the mass was retroareolar in 46% (n=6) and eccentric to the nipple in 54% (n=7) of patients. On ultrasonography (US), the contours were well-circumscribed in 20% (n=3) and irregular in 80% (n=12) of the masses. Conclusion: Male breast has a wide spectrum of diseases, some of which have characteristic radiological appearances that can be correlated with their pathologic diagnosis. In the evaluation of the male breast, mammography and US are essential and should be performed along with physical examination.

  12. Development of breast phantom for quality assessment of mammographic images

    Energy Technology Data Exchange (ETDEWEB)

    Arvelos, Jeniffer Miranda; Flores, Mabel Bustos; Amaral, Fernando; Rio, Margarita Chevalier del; Mourao, Arnaldo Prata, E-mail: jenifferarvelos00@gmail.com [Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Centro de Engenharia Biomedica; Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Universidad Complutense de Madrid (UCM), Madrid (Spain). Faculdad de Medicina. Departmento de Radiologia

    2017-11-01

    Diagnosis of breast cancer in young women may be impaired by the tissue composition of breast in this age group, as fibroglandular tissue is present in greater amount in young women and it has higher density than fibrous and fatty tissues which predominate in women older than 40 years old. The higher density of breast tissue makes it difficult to identify nodules in two-dimensional techniques, due to the overlapping of dense layers. Breast phantoms are used in evaluation and quality control of clinical images, and therefore, it is important to develop non-homogeneous phantoms that may better simulate a real breast. Grouped microcalcifications are often the earliest changes associated with malignant neoplasm of breast. In this work, a phantom was developed in the form of a compressed breast using acrylic resin blend. The resin blend used to fulfill the interior of the phantom has similar mammographic density to the one in fibroglandular tissue, representing a dense breast. The lesions were made of acrylic resin blend and calcium compounds that might simulate breast abnormalities, representing nodules, macrocalcifications and microcalcifications of different dimensions and densities. They were distributed into the ma-terial representing fibroglandular tissue. The developed phantom has a thickness of 1 cm, and it may be matched with other plates to represent a dense breast of thickness between 5 and 6 cm. The main goal of the project is to evaluate the sensitivity of detection of these calcifications in relation to their density and location in the breast in two-dimensional images generated in mammography equipment. Mammographic images allow the visualization of the changes implemented in the phantom. The developed phantom may be used in evaluation of diagnostic images generated through two-dimensional and three-dimensional images. (author)

  13. Fibrocystic disease of breast: variable mammographic and sonography appearance

    Energy Technology Data Exchange (ETDEWEB)

    Han, Heon; Cha, Yoo Mi; Yang, Joo Hyun; Song, Ek Hyun; Hwang, Hee Yong; Chung, Hyo Sun; Park, Sung Hye [Chung Ang Gil Hospital, Incheon (Korea, Republic of)

    1993-12-15

    Fibrocystic disease of the breast is a frequent cause of abnormal mammogram and ultrasonogram in patients with breast pain. The differentiation of fibrocystic disease form fibroadenoma or carcinoma is often difficult. The present study was performed to evaluate the mammographic and sonographic features of fibrocystic disease of the breast Mammograms and sonogram s of 45 patients with pathologically proven fibrocystic disease of breast were analyzed and correlated retrospectively with the pathologic specimens. Clinically the patients had palpable breast lumps or focal skin thickening. The patients were aged 19 to 64 years(average, 37 years) Histologic examination of 29 patients with abnormal findings in mammograms and/or sonograms revealed stromal fibrosis in 28(97%), cyst formation in 24(83%), epithelial hyperplasia in 29(90%), apocrine metaplasia in 7 (24%), chronic inflammation in 15 (52%), fibroadenomatous change in 2 (7%), large pseudocyst formation in 2 (7%), calcification in 1 (3%), and/or chondroid maseptol in 1 (3%). Of 43 patients with mammograms, 23 showed no detectable lesion, even in retrospect, because of dense mammograms there were well marginated mass in 7, poorly marginated mass in 4, multiple small nodules in 2, mixed density radio opaque mass in 3, radiolucent mass in one, and asymmetrical dense breast in 3. One case had calcification within the mass, and another one had very high density nodules that showed chondroid metaplasia. In 14 patients with sonograms, the echogenicity was variable; anechoic in 2, hypoechoic in 8, isoechoic in 3, or mixed echoic in one. The shape of the lesion was round in 2, ovoid in 8, tubular in 2, and irregular in 2. The margin was well marginated in 11 and poorly marginated in 3. Fibrocystic breast disease, which is a frequent cause of breast lumps, has variable findings in mammograms and sonograms. Therefore, fibrocystic disease should be included in the differential diagnosis of breast mass when the typical

  14. Fibrocystic disease of breast: variable mammographic and sonography appearance

    International Nuclear Information System (INIS)

    Han, Heon; Cha, Yoo Mi; Yang, Joo Hyun; Song, Ek Hyun; Hwang, Hee Yong; Chung, Hyo Sun; Park, Sung Hye

    1993-01-01

    Fibrocystic disease of the breast is a frequent cause of abnormal mammogram and ultrasonogram in patients with breast pain. The differentiation of fibrocystic disease form fibroadenoma or carcinoma is often difficult. The present study was performed to evaluate the mammographic and sonographic features of fibrocystic disease of the breast Mammograms and sonogram s of 45 patients with pathologically proven fibrocystic disease of breast were analyzed and correlated retrospectively with the pathologic specimens. Clinically the patients had palpable breast lumps or focal skin thickening. The patients were aged 19 to 64 years(average, 37 years) Histologic examination of 29 patients with abnormal findings in mammograms and/or sonograms revealed stromal fibrosis in 28(97%), cyst formation in 24(83%), epithelial hyperplasia in 29(90%), apocrine metaplasia in 7 (24%), chronic inflammation in 15 (52%), fibroadenomatous change in 2 (7%), large pseudocyst formation in 2 (7%), calcification in 1 (3%), and/or chondroid maseptol in 1 (3%). Of 43 patients with mammograms, 23 showed no detectable lesion, even in retrospect, because of dense mammograms there were well marginated mass in 7, poorly marginated mass in 4, multiple small nodules in 2, mixed density radio opaque mass in 3, radiolucent mass in one, and asymmetrical dense breast in 3. One case had calcification within the mass, and another one had very high density nodules that showed chondroid metaplasia. In 14 patients with sonograms, theechogenicity was variable ; anechoic in 2, hypoechoic in 8, isoechoic in 3, or mixed echoic in one. The shape of the lesion was round in 2, ovoid in 8, tubular in 2, and irregular in 2. The margin was well marginated in 11 and poorly marginated in 3. Fibrocystic breast disease, which is a frequent cause of breast lumps, has variable findings in mammograms and sonograms. Therefore, fibrocystic disease should be included in the differential diagnosis of breast mass when the typical

  15. Development of breast phantom for quality assessment of mammographic images

    International Nuclear Information System (INIS)

    Arvelos, Jeniffer Miranda; Flores, Mabel Bustos; Amaral, Fernando; Rio, Margarita Chevalier del; Mourao, Arnaldo Prata; Universidade Federal de Minas Gerais; Universidad Complutense de Madrid

    2017-01-01

    Diagnosis of breast cancer in young women may be impaired by the tissue composition of breast in this age group, as fibroglandular tissue is present in greater amount in young women and it has higher density than fibrous and fatty tissues which predominate in women older than 40 years old. The higher density of breast tissue makes it difficult to identify nodules in two-dimensional techniques, due to the overlapping of dense layers. Breast phantoms are used in evaluation and quality control of clinical images, and therefore, it is important to develop non-homogeneous phantoms that may better simulate a real breast. Grouped microcalcifications are often the earliest changes associated with malignant neoplasm of breast. In this work, a phantom was developed in the form of a compressed breast using acrylic resin blend. The resin blend used to fulfill the interior of the phantom has similar mammographic density to the one in fibroglandular tissue, representing a dense breast. The lesions were made of acrylic resin blend and calcium compounds that might simulate breast abnormalities, representing nodules, macrocalcifications and microcalcifications of different dimensions and densities. They were distributed into the ma-terial representing fibroglandular tissue. The developed phantom has a thickness of 1 cm, and it may be matched with other plates to represent a dense breast of thickness between 5 and 6 cm. The main goal of the project is to evaluate the sensitivity of detection of these calcifications in relation to their density and location in the breast in two-dimensional images generated in mammography equipment. Mammographic images allow the visualization of the changes implemented in the phantom. The developed phantom may be used in evaluation of diagnostic images generated through two-dimensional and three-dimensional images. (author)

  16. Digital breast tomosynthesis for breast cancer screening and diagnosis in women with dense breasts - a systematic review and meta-analysis

    NARCIS (Netherlands)

    Phi, Xuan-Anh; Tagliafico, Alberto; Houssami, Nehmat; Greuter, Marcel J W; de Bock, Geertruida H

    2018-01-01

    BACKGROUND: This study aimed to systematically review and to meta-analyse the accuracy of digital breast tomosynthesis (DBT) versus digital mammography (DM) in women with mammographically dense breasts in screening and diagnosis. METHODS: Two independent reviewers identified screening or diagnostic

  17. Digital breast tomosynthesis for breast cancer screening and diagnosis in women with dense breasts - a systematic review and meta-analysis

    NARCIS (Netherlands)

    Phi, Xuan-Anh; Tagliafico, Alberto; Houssami, Nehmat; Greuter, Marcel J. W.; de Bock, Geertruida H.

    2018-01-01

    Background: This study aimed to systematically review and to meta-analyse the accuracy of digital breast tomosynthesis (DBT) versus digital mammography (DM) in women with mammographically dense breasts in screening and diagnosis. Methods: Two independent reviewers identified screening or diagnostic

  18. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission`s dispositions

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Norio; Suzudo, Tomoaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission`s (USNRC`s) responses to the recommendations made by the NRC`s study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC`s dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  19. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission's dispositions

    International Nuclear Information System (INIS)

    Watanabe, Norio; Suzudo, Tomoaki

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission's (USNRC's) responses to the recommendations made by the NRC's study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC's dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  20. Determinants of frequent Internet use in an urban kidney transplant population in the United States: characterizing the digital divide.

    Science.gov (United States)

    Lockwood, Mark; Saunders, Milda; Josephson, Michelle A; Becker, Yolanda T; Lee, Christopher

    2015-03-01

    The Internet is a staple of electronic communication and is essential to the emerging telemonitoring and health information technology interventions for adults with chronic diseases. To identify determinants of frequent Internet use in an urban kidney transplant population in the United States. A single center, cross-sectional survey study. An urban Midwestern transplant center. 78 pretransplant and 177 posttransplant patients. Frequent Internet use, defined as using the Internet more than 5 hours per week. Only 38% of participants reported being frequent Internet users. Non-Hispanic blacks and participants who reported their race/ethnicity as "other" were significantly less likely than whites to report being frequent Internet users. Women were 59% less likely than men to be frequent users of the Internet. Those who reported having kidney disease for more than 3 years were more likely to report being frequent Internet users. As education increased, Internet use increased. As age increased, Internet use decreased. Alternatives to electronic information sources and/or additional resources should be considered for those who may fall in the so-called digital divide.

  1. Contrast enhanced digital mammography: Is it useful in detecting lesions in edematous breast?

    Directory of Open Access Journals (Sweden)

    Noha Abd ElShafy ElSaid

    2015-09-01

    Conclusion: Dual-energy contrast-enhanced digital mammography is a useful technique in identification of lesions in mammographically dense edematous breasts and proved to be a useful tool in the follow-up of cases presenting by edema after conservative breast surgery and chemotherapy.

  2. Comparison of dignity determination of mammographic microcalcification with two systems for digital full-field mammography with different detector resolution. A retrospective clinical study; Vergleich der Dignitaetsbestimmung von mammographischem Mikrokalk mit zwei Systemen zur digitalen Vollfeldmammographie unterschiedlicher Detektoraufloesung. Eine retrospektive klinische Studie

    Energy Technology Data Exchange (ETDEWEB)

    Schulz-Wendtland, R.; Adamietz, B.; Meier-Meitinger, M.; Wenkel, E.; Lell, M.; Anders, K.; Uder, M. [Universitaetsklinikum Erlangen, Abteilung Gynaekologische Radiologie, Radiologisches Institut, Erlangen (Germany); Hermann, K.P. [Universitaetsmedizin Goettingen, Abteilung Diagnostische Radiologie, Goettingen (Germany)

    2011-02-15

    The aim of this retrospective clinical study was to compare the diagnostic accuracy of the novel 50 {mu}m FFDM (full-field digital mammography) system (DR) with an established 70 {mu}m system (DR) in the differential diagnosis between benign and malignant clusters of microcalcification (n=50) (BI-RADS trademark classification 4/5) and to assess the possible incremental value of the 50 {mu}m pixel-pitch on specificity. From March 2009 to September 2009, 50 patients underwent full-field digital mammography (FFDM) (detector resolution 70 {mu}m) (Novation, Siemens, Erlangen, Germany). As there were suspicious signs of microcalcification classified with BI-RADS trademark 4/5 after diagnosis and preoperative wire localization, control images were made with the new FFDM system (detector: resolution 50 {mu}m) (Amulet, Fujifilm, Tokyo, Japan) with the same exposure parameters. The diagnosis was determined after the operation by five radiologists with different experience in digital mammography from randomly distributed mediolateral views (monitor reading) whose results were correlated with the final histology of all lesions. Histopathology revealed 19 benign and 31 malignant lesions in 50 patients after open biopsy. The results of the five readers showed a higher sensitivity of the new FFDM system (80.0%) in the ability to recognize malignant microcalcification in comparison to the established system (74.8%). The specificity (75.8 versus 71.6%) was slightly higher for the new system but hese results were not statistically significant (p<0.001). Considering the diagnostic accuracy, the new system (detector: resolution 50 {mu}m) was also slightly superior to the well-known system (detector: resolution 70 {mu}m) (80.1% versus 76.4%). Our study has shown that the new full-field digital mammography system using the novel detector compared with the already established FFDM system with respect to the assessment of microcalcification is at least equivalent. (orig.) [German] Das

  3. Clinical evaluation of JPEG2000 compression for digital mammography

    Science.gov (United States)

    Sung, Min-Mo; Kim, Hee-Joung; Kim, Eun-Kyung; Kwak, Jin-Young; Yoo, Jae-Kyung; Yoo, Hyung-Sik

    2002-06-01

    Medical images, such as computed radiography (CR), and digital mammographic images will require large storage facilities and long transmission times for picture archiving and communications system (PACS) implementation. American College of Radiology and National Equipment Manufacturers Association (ACR/NEMA) group is planning to adopt a JPEG2000 compression algorithm in digital imaging and communications in medicine (DICOM) standard to better utilize medical images. The purpose of the study was to evaluate the compression ratios of JPEG2000 for digital mammographic images using peak signal-to-noise ratio (PSNR), receiver operating characteristic (ROC) analysis, and the t-test. The traditional statistical quality measures such as PSNR, which is a commonly used measure for the evaluation of reconstructed images, measures how the reconstructed image differs from the original by making pixel-by-pixel comparisons. The ability to accurately discriminate diseased cases from normal cases is evaluated using ROC curve analysis. ROC curves can be used to compare the diagnostic performance of two or more reconstructed images. The t test can be also used to evaluate the subjective image quality of reconstructed images. The results of the t test suggested that the possible compression ratios using JPEG2000 for digital mammographic images may be as much as 15:1 without visual loss or with preserving significant medical information at a confidence level of 99%, although both PSNR and ROC analyses suggest as much as 80:1 compression ratio can be achieved without affecting clinical diagnostic performance.

  4. Ambient dose evaluation at mammographic installations through the spectrum of barrier transmitted beams

    International Nuclear Information System (INIS)

    Silva, Marcia C.; Costa, Paulo R.; Herdade, Silvio B.; Furquim, Tania A.C.; Terini, Ricardo A.

    2001-01-01

    National regulations (Ministerial Rule 453, 1998) state that ambient dose equivalent (ADE) must be the operational quantity to verify the conformance with dose constraint levels in area surveys. It's difficulty to evaluate ADE's through conventional radiometric measurements performed in the neighbor areas of examination room because of the low energy levels utilized by mammographic equipment. Therefore, it is necessary to know the radiation spectrum incident in the area. Spectra of X-rays scattered by a breast tissue equivalent phantom have been measured in a controlled area adjacent to a mammography room, using a portable high resolution spectrometer, and taking into account typical workload distributions. The raw spectra was corrected for changes of detector efficiency with photon energy and converted to fluence units (photons/keV.m 2 ). After, air kerma values (in mGy/m As) was calculated for each corrected spectrum. The ADE's (in mSv/year) was obtained by two ways: firstly using the constant conversion factor 1.14 Sv/Gy, adopted by the Ministerial Rule 453 and used in ionization chambers; secondly, through the conversion factor (Sv/Gy) versus energy curve. Results show clearly that the ADE values are overestimated when adopting the usual methodology and that the proposed method furnishes more realistic data for the evaluation of protective shielding. (author)

  5. Age as a predictive factor of mammographic breast density in Jamaican women

    International Nuclear Information System (INIS)

    Soares, Deanne; Reid, Marvin; James, Michael

    2002-01-01

    AIM: We sought to determine the relationship between age, and other clinical characteristics such as parity, oestrogen use, dietary factors and menstrual history on breast density in Jamaican women. METHODS AND MATERIALS: A retrospective study was done of 891 patients who attended the breast imaging unit. The clinical characteristics were extracted from the patient records. Mammograms were assessed independently by two radiologists who were blinded to the patient clinical characteristics. Breast densities were assigned using the American College of Radiology (ACR) classification. RESULTS: The concordance between the ACR classification of breast density between the two independent radiologists was 92% with k = 0.76 (SE = 0.02, P -2 vs 26.0 ± 5.2 kg m -2 , P < 0.0001). Mammographic breast density decreased with age. The age adjusted odds ratios (ORs) for predictors significantly related to high breast density were parity, OR = 0.79 (95%CI:0.71, 0.88), weight, OR = 0.92 (95% CI:0.91, 0.95), BMI, OR = 0.83 (95% CI:0.78, 0.89), menopause, OR = 0.51 (95% CI:0.36, 0.74) and a history of previous breast surgery, OR 1.6 (95% CI:1.1, 2.3). CONCLUSION: The rate decline of breast density with age in our population was influenced by parity and body composition. Soares, D. et al. (2002)

  6. Occupation and mammographic density: A population-based study (DDM-Occup).

    Science.gov (United States)

    García-Pérez, Javier; Pollán, Marina; Pérez-Gómez, Beatriz; González-Sánchez, Mario; Cortés Barragán, Rosa Ana; Maqueda Blasco, Jerónimo; González-Galarzo, María Carmen; Alba, Miguel Ángel; van der Haar, Rudolf; Casas, Silvia; Vicente, Cándida; Medina, Pilar; Ederra, María; Santamariña, Carmen; Moreno, María Pilar; Casanova, Francisco; Pedraz-Pingarrón, Carmen; Moreo, Pilar; Ascunce, Nieves; García, Montse; Salas-Trejo, Dolores; Sánchez-Contador, Carmen; Llobet, Rafael; Lope, Virginia

    2017-11-01

    High mammographic density is one of the main risk factors for breast cancer. Although several occupations have been associated with breast cancer, there are no previous occupational studies exploring the association with mammographic density. Our objective was to identify occupations associated with high mammographic density in Spanish female workers. We conducted a population-based cross-sectional study of occupational determinants of high mammographic density in Spain, based on 1476 women, aged 45-68 years, recruited from seven screening centers within the Spanish Breast Cancer Screening Program network. Reproductive, family, personal, and occupational history data were collected. The latest occupation of each woman was collected and coded according to the 1994 National Classification of Occupations. Mammographic density was assessed from the cranio-caudal mammogram of the left breast using a semi-automated computer-assisted tool. Association between mammographic density and occupation was evaluated by using mixed linear regression models, using log-transformed percentage of mammographic density as dependent variable. Models were adjusted for age, body mass index, menopausal status, parity, smoking, alcohol intake, educational level, type of mammography, first-degree relative with breast cancer, and hormonal replacement therapy use. Screening center and professional reader were included as random effects terms. Mammographic density was higher, although non-statistically significant, among secondary school teachers (e β = 1.41; 95%CI = 0.98-2.03) and nurses (e β = 1.23; 95%CI = 0.96-1.59), whereas workers engaged in the care of people (e β = 0.81; 95%CI = 0.66-1.00) and housewives (e β = 0.87; 95%CI = 0.79-0.95) showed an inverse association with mammographic density. A positive trend for every 5 years working as secondary school teachers was also detected (p-value = 0.035). Nurses and secondary school teachers were the occupations with the highest

  7. 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)

  8. 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.

  9. Correlation between the physical performances measured from detectors and the diagnostic image quality in digital mammography

    International Nuclear Information System (INIS)

    Perez-Ponce, H.

    2009-05-01

    In digital mammography two approaches exist to estimate image quality. In the first approach, human observer assesses the lesion detection in mammograms. Unfortunately, such quality assessment is subject to interobserver variability, and requires a large amount of time and human resources. In the second approach, objective and human-independent parameters relating to image spatial resolution and noise (MTF and NPS) are used to evaluate digital detector performance; even if these parameters are objective, they are not directly related to lesion detection. A method leading to image quality assessment which is both human independent, and directly related to lesion detection is very important for the optimal use of mammographic units. This Ph.D thesis presents the steps towards such a method: the computation of realistic virtual images using an 'X ray source/digital detector' model taking into account the physical parameters of the detector (spatial resolution and noise measurements) measured under clinical conditions. From results obtained in this work, we have contributed to establish the link between the physical characteristics of detectors and the clinical quality of the image for usual exposition conditions. Furthermore, we suggest the use of our model for the creation of virtual images, in order to rapidly determine the optimal conditions in mammography, which usually is a long and tedious experimental process. This is an essential aspect to be taken into account for radioprotection of patients, especially in the context of organized mass screening of breast cancer. (author)

  10. Feature extraction using convolutional neural network for classifying breast density in mammographic images

    Science.gov (United States)

    Thomaz, Ricardo L.; Carneiro, Pedro C.; Patrocinio, Ana C.

    2017-03-01

    Breast cancer is the leading cause of death for women in most countries. The high levels of mortality relate mostly to late diagnosis and to the direct proportionally relationship between breast density and breast cancer development. Therefore, the correct assessment of breast density is important to provide better screening for higher risk patients. However, in modern digital mammography the discrimination among breast densities is highly complex due to increased contrast and visual information for all densities. Thus, a computational system for classifying breast density might be a useful tool for aiding medical staff. Several machine-learning algorithms are already capable of classifying small number of classes with good accuracy. However, machinelearning algorithms main constraint relates to the set of features extracted and used for classification. Although well-known feature extraction techniques might provide a good set of features, it is a complex task to select an initial set during design of a classifier. Thus, we propose feature extraction using a Convolutional Neural Network (CNN) for classifying breast density by a usual machine-learning classifier. We used 307 mammographic images downsampled to 260x200 pixels to train a CNN and extract features from a deep layer. After training, the activation of 8 neurons from a deep fully connected layer are extracted and used as features. Then, these features are feedforward to a single hidden layer neural network that is cross-validated using 10-folds to classify among four classes of breast density. The global accuracy of this method is 98.4%, presenting only 1.6% of misclassification. However, the small set of samples and memory constraints required the reuse of data in both CNN and MLP-NN, therefore overfitting might have influenced the results even though we cross-validated the network. Thus, although we presented a promising method for extracting features and classifying breast density, a greater database is

  11. Cost-effectiveness of annual versus biennial screening mammography for women with high mammographic breast density.

    Science.gov (United States)

    Pataky, Reka; Ismail, Zahra; Coldman, Andrew J; Elwood, Mark; Gelmon, Karen; Hedden, Lindsay; Hislop, Greg; Kan, Lisa; McCoy, Bonnie; Olivotto, Ivo A; Peacock, Stuart

    2014-12-01

    The sensitivity of screening mammography is much lower among women who have dense breast tissue, compared with women who have largely fatty breasts, and they are also at much higher risk of developing the disease. Increasing mammography screening frequency from biennially to annually has been suggested as a policy option to address the elevated risk in this population. The purpose of this study was to assess the cost-effectiveness of annual versus biennial screening mammography among women aged 50-79 with dense breast tissue. A Markov model was constructed based on screening, diagnostic, and treatment pathways for the population-based screening and cancer care programme in British Columbia, Canada. Model probabilities and screening costs were calculated from screening programme data. Costs for breast cancer treatment were calculated from treatment data, and utility values were obtained from the literature. Incremental cost-effectiveness was expressed as cost per quality adjusted life year (QALY), and probabilistic sensitivity analysis was conducted. Compared with biennial screening, annual screening generated an additional 0.0014 QALYs (95% CI: -0.0480-0.0359) at a cost of $819 ($ = Canadian dollars) per patient (95% CI: 506-1185), resulting in an incremental cost effectiveness ratio of $565,912/QALY. Annual screening had a 37.5% probability of being cost-effective at a willingness-to-pay threshold of $100,000/QALY. There is considerable uncertainty about the incremental cost-effectiveness of annual mammography. Further research on the comparative effectiveness of screening strategies for women with high mammographic breast density is warranted, particularly as digital mammography and density measurement become more widespread, before cost-effectiveness can be reevaluated. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  12. Impact of Breast Reader Assessment Strategy on mammographic radiologists' test reading performance.

    Science.gov (United States)

    Suleiman, Wasfi I; Rawashdeh, Mohammad A; Lewis, Sarah J; McEntee, Mark F; Lee, Warwick; Tapia, Kriscia; Brennan, Patrick C

    2016-06-01

    The detection of breast cancer is somewhat limited by human factors, and thus there is a need to improve reader performance. This study assesses whether radiologists who regularly undertake the education in the form of the Breast Reader Assessment Strategy (BREAST) demonstrate any changes in mammography interpretation performance over time. In 2011, 2012 and 2013, 14 radiologists independently assessed a year-specific BREAST mammographic test-set. Radiologists read a different single test-set once each year, with each comprising 60 digital mammogram cases. Radiologists marked the location of suspected lesions without computer-aided diagnosis (CAD) and assigned a confidence rating of 2 for benign and 3-5 for malignant lesions. The mean sensitivity, specificity, location sensitivity, JAFROC FOM and ROC AUC were calculated. A Kruskal-Wallis test was used to compare the readings for the 14 radiologists across the 3 years. Wilcoxon signed rank test was used to assess comparison between pairs of years. Relationships between changes in performance and radiologist characteristics were examined using a Spearman's test. Significant increases were noted in mean sensitivity (P = 0.01), specificity (P = 0.01), location sensitivity (P = 0.001) and JAFROC FOM (P = 0.001) between 2011 and 2012. Between 2012 and 2013, significant improvements were noted in mean sensitivity (P = 0.003), specificity (P = 0.002), location sensitivity (P = 0.02), JAFROC FOM (P = 0.005) and ROC AUC (P = 0.008). No statistically significant correlations were shown between the levels of improvement and radiologists' characteristics. Radiologists' who undertake the BREAST programme demonstrate significant improvements in test-set performance during a 3-year period, highlighting the value of ongoing education through the use of test-set. © 2016 The Royal Australian and New Zealand College of Radiologists.

  13. Area and volumetric density estimation in processed full-field digital mammograms for risk assessment of breast cancer.

    Directory of Open Access Journals (Sweden)

    Abbas Cheddad

    Full Text Available INTRODUCTION: Mammographic density, the white radiolucent part of a mammogram, is a marker of breast cancer risk and mammographic sensitivity. There are several means of measuring mammographic density, among which are area-based and volumetric-based approaches. Current volumetric methods use only unprocessed, raw mammograms, which is a problematic restriction since such raw mammograms are normally not stored. We describe fully automated methods for measuring both area and volumetric mammographic density from processed images. METHODS: The data set used in this study comprises raw and processed images of the same view from 1462 women. We developed two algorithms for processed images, an automated area-based approach (CASAM-Area and a volumetric-based approach (CASAM-Vol. The latter method was based on training a random forest prediction model with image statistical features as predictors, against a volumetric measure, Volpara, for corresponding raw images. We contrast the three methods, CASAM-Area, CASAM-Vol and Volpara directly and in terms of association with breast cancer risk and a known genetic variant for mammographic density and breast cancer, rs10995190 in the gene ZNF365. Associations with breast cancer risk were evaluated using images from 47 breast cancer cases and 1011 control subjects. The genetic association analysis was based on 1011 control subjects. RESULTS: All three measures of mammographic density were associated with breast cancer risk and rs10995190 (p0.10 for risk, p>0.03 for rs10995190. CONCLUSIONS: Our results show that it is possible to obtain reliable automated measures of volumetric and area mammographic density from processed digital images. Area and volumetric measures of density on processed digital images performed similar in terms of risk and genetic association.

  14. State-wide provision of a digital mammography physics service : challenges and learning experiences

    International Nuclear Information System (INIS)

    Diffey, J.L.; Cartwright, L.E.; Collins, L.T.; Grewal, R.K.

    2010-01-01

    Full text: Breast Screen NSW is a fully digital screening programme with 70 mammographic units from eight vendors. We present the challenges and learning experiences associated with providing the physics service to this extensive screening programme. The EPA requires an annual check of Mean Glandular Dose and registration renewal every 2 years. Additionally, BreastScreen NSW requires annual compliance testing to RANZCR standards. To ensure that testing is carried out to a consistently high level, the contract specifies that only five physicists in the state are eligible to test the equipment. An equipment database has been developed to enable us to meet these deadlines. We have also created a radiog rapher QC manual. Two physicists take responsibility for the overall co-ordination of the service, reviewing reports and test methodology of other physics providers. The database has greatly improved the system for meeting deadlines; visits to all sites revealed that many were overdue. The radiographer QC manual has been accompanied by practical tutorials and has been successful in improving understanding of digital mam mography and ensuring consistency in testing. This has been a particular challenge because equipment has been supplied by a number of vendors, with a range of detector technology. The number of mammography units, combined with the range of vendor technology and frequency of testing has presented a challenge to both physicists and radiographers. It has been extremely beneficial to have two dedicated physicists in place to co-ordinate the service and ensure that the demands of the contract are met.

  15. Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina

    Science.gov (United States)

    Williams, Lester J.; Dixon, Joann F.

    2015-01-01

    Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. The dataset contains structural surfaces depicting the top and base of the aquifer system, its major and minor hydrogeologic units and zones, geophysical marker horizons, and the altitude of the 10,000-milligram-per-liter total dissolved solids boundary that defines the approximate fresh and saline parts of the aquifer system. The thicknesses of selected major and minor units or zones were determined by interpolating points of known thickness or from raster surface subtraction of the structural surfaces. Additional data contained include clipping polygons; regional polygon features that represent geologic or hydrogeologic aspects of the aquifers and the minor units or zones; data points used in the interpolation; and polygon and line features that represent faults, boundaries, and other features in the aquifer system.

  16. The mammographic correlations of a new immunohistochemical classification of invasive breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Taneja, S. [Nottingham Breast Institute, City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom)], E-mail: sheeba_taneja@yahoo.co.uk; Evans, A.J. [Nottingham Breast Institute, City Hospital, Hucknall Road, Nottingham NG5 1PB (United Kingdom); Rakha, E.A.; Green, A.R. [Division of Pathology, School of Molecular Medical Sciences, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham (United Kingdom); Ball, G. [Nottingham Trent University, School of Biomedical and Natural Sciences, Nottingham (United Kingdom); Ellis, I.O. [Division of Pathology, School of Molecular Medical Sciences, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham (United Kingdom)

    2008-11-15

    Aim: Recent protein expression profiling of breast cancer has identified specific subtypes with clinical, biological, and therapeutic implications. The aim of this study was to identify the mammographic correlates of these novel molecular classes of invasive breast cancer. Materials and methods: The mammographic findings of 415 patients with operable breast cancer were correlated with the previously described protein expression classes identified by our group using immunohistochemical (IHC) assessment of a large series of breast cancer cases prepared as tissue microarrays (TMAs). Twenty-five proteins of known relevance in breast cancer were assessed, including hormone receptors, HER-2 status, basal and luminal markers, p53 expression, and E-cadherin. Results: The mammographic background pattern and proportion of lesions that were mammographically occult were similar in all groups. Groups characterized by luminal and hormone receptor positivity had significantly more spiculate lesions at mammography. Groups characterized by HER-2 overexpression, basal characteristics, and E-cadherin positivity had a significantly higher proportion of ill-defined masses. These findings were independent of histological grade. Conclusion: The mammographic features of breast cancer show significant correlation with molecular classes of invasive breast cancer identified by protein expression IHC analysis. The biological reasons for the findings and implications of these regarding imaging protocols require further study and may provide mechanisms for improvement of detection of these lesions.

  17. Mammographic breast density patterns in asymptomatic mexican women.

    Science.gov (United States)

    Calderón-Garcidueñas, Ana Laura; Sanabria-Mondragón, Mónica; Hernández-Beltrán, Lourdes; López-Amador, Noé; Cerda-Flores, Ricardo M

    2012-01-01

    Breast density (BD) is a risk factor for breast cancer. Aims. To describe BD patterns in asymptomatic Mexican women and the pathological mammographic findings. Methods and Material. Prospective, descriptive, and comparative study. Women answered a questionnaire and their mammograms were analyzed according to BI-RADS. Univariate (χ(2)) and conditional logistic regression analyses were performed. Results. In 300 women studied the BD patterns were fat 56.7% (170), fibroglandular 29% (87), heterogeneously dense 5.7% (17), and dense pattern 8.6% (26). Prevalence of fat pattern was significantly different in women under 50 years (37.6%, 44/117) and older than 50 (68.8%, 126/183). Patterns of high breast density (BD) (dense + heterogeneously dense) were observed in 25.6% (30/117) of women ≤50 years and 7.1% (13/183) of women >50. Asymmetry in BD was observed in 22% (66/300). Compression cone ruled out underlying disease in 56 cases. In the remaining 10, biopsy revealed one fibroadenoma, one complex cyst, and 6 invasive and 2 intraductal carcinomas. 2.6% (8/300) of patients had non-palpable carcinomas. Benign lesions were observed in 63.3% (190/300) of cases, vascular calcification in 150 cases (78.9%), and fat necrosis in 38 cases (20%). Conclusions. Mexican women have a low percentage of high-density patterns.

  18. Effects of repeated mammographic screening on breast cancer stage distribution

    International Nuclear Information System (INIS)

    Fagerberg, G.; Baldetorp, L.; Groentoft, O.; Lundstroem, B.; Maanson, J.C.; Nordenskjoeld, B.

    1985-01-01

    A randomised controlled trial of mass screening for breast cancer by single-view mammography was begun in Sweden in 1977. All women aged 40 and older and resident in the counties of Koppaberg and Oestergoetland were enrolled. The present report is confined to the Oestergoetland study, which started in 1978 and comprised 92934 women. After randomisation, which was done on the basis of communities rather than individuals, 47001 women were allocated to the study group and offered repeated mammographic screening; 45933 were allocated to the control group. As compliance among women over 74 years of age was poor these were excluded from the present report. The yearly incidence of stage II or more advanced breast cancers after the initial screening round up to and including the second was reduced by 40 per cent in the study group compared with the controls. This effect was less marked in the age group 40-49. After 5.5 years average from the date of entry the absolute number of women with stage II-IV disease in the control group exceeded that for the study group by 44, whereas there was a large excess of cancer in situ and stage I cancer in the study group. (orig.)

  19. Mammographic Breast Density Patterns in Asymptomatic Mexican Women

    International Nuclear Information System (INIS)

    Calderón-Garcidueñas, Ana Laura; Sanabria-Mondragón, Mónica; Hernández-Beltrán, Lourdes; López-Amador, Noé; Cerda-Flores, Ricardo M.

    2012-01-01

    Breast density (BD) is a risk factor for breast cancer. Aims. To describe BD patterns in asymptomatic Mexican women and the pathological mammographic findings. Methods and Material. Prospective, descriptive, and comparative study. Women answered a questionnaire and their mammograms were analyzed according to BI-RADS. Univariate (χ 2 ) and conditional logistic regression analyses were performed. Results. In 300 women studied the BD patterns were fat 56.7% (170), fibroglandular 29% (87), heterogeneously dense 5.7% (17), and dense pattern 8.6% (26). Prevalence of fat pattern was significantly different in women under 50 years (37.6%, 44/117) and older than 50 (68.8%, 126/183). Patterns of high breast density (BD) (dense + heterogeneously dense) were observed in 25.6% (30/117) of women ≤50 years and 7.1% (13/183) of women >50. Asymmetry in BD was observed in 22% (66/300). Compression cone ruled out underlying disease in 56 cases. In the remaining 10, biopsy revealed one fibroadenoma, one complex cyst, and 6 invasive and 2 intraductal carcinomas. 2.6% (8/300) of patients had non-palpable carcinomas. Benign lesions were observed in 63.3% (190/300) of cases, vascular calcification in 150 cases (78.9%), and fat necrosis in 38 cases (20%). Conclusions. Mexican women have a low percentage of high-density patterns

  20. Mammographic Breast Density Patterns in Asymptomatic Mexican Women

    International Nuclear Information System (INIS)

    Garciduenas, A.L.C.; Amador, N.; Mondragon, M.S.; Hernaan, L.; Cerda-Flores, R.M.

    2012-01-01

    Breast density (BD) is a risk factor for breast cancer. Aims. To describe BD patterns in asymptomatic Mexican women and the pathological mammographic findings. Methods and Material. Prospective, descriptive, and comparative study. Women answered a questionnaire and their mammograms were analyzed according to BI-RADS. Univariate (X 2 ) and conditional logistic regression analyses were performed. Results. In 300 women studied the BD patterns were fat 56.7% (170), fibroglandular 29% (87), heterogeneously dense 5.7% (17), and dense pattern 8.6% (26). Prevalence of fat pattern was significantly different in women under 50 years (37.6%, 44/117) and older than 50 (68.8%, 126/183). Patterns of high breast density (BD) (dense + heterogeneously dense) were observed in 25.6% (30/117) of women ≤50 years and 7.1% (13/183) of women >50. Asymmetry in BD was observed in 22% (66/300). Compression cone ruled out underlying disease in 56 cases. In the remaining 10, biopsy revealed one fibroadenoma, one complex cyst, and 6 invasive and 2 intraductal carcinomas. 2.6% (8/300) of patients had non-palpable carcinomas. Benign lesions were observed in 63.3% (190/300) of cases, vascular calcification in 150 cases (78.9%), and fat necrosis in 38 cases (20%). Conclusions. Mexican women have a low percentage of high-density patterns

  1. A study of mammographic and thermographic findings in breast diseases

    International Nuclear Information System (INIS)

    Cho, Won Sik; Jeon, Woo Ki; Kim, Jeong Sook; Han, Chang Yul

    1989-01-01

    The ideal diagnostic methods in breast diseases consist of the physical examination and complementary radiologic examination. In radiologic examination mammography is the most popular screening methods and the older simple complementary method is thermography which is efficient under the conditions of elevated skin temperature in inflammatory and malignant lesions. From Jan. 1st 1987 through Jan. 30th, 1988, 110 pts. with complaints of mammary problems were examined by mammography and thermography at Paik Hospital, Inje University. The authors selected and analyzed 97 cases had been pathologically proved through the operation and the fine needle aspiration biopsy. The results were as follows: 1. The most prevalent age group was 5th decade (40%) in cancer, 4th decade (47%) in mammary dysplasia and followed by fibroadenoma (63%) in 4th decade. 2. The mammographic and thermographic findings were compared between the mammary dysplasia and the infiltrating ductal cancer. In mammary dysplasia abnormal hot emissions were appeared in 9/44 (17%) correlated with atypical hyperchromatic cytoplasm relates to pre-malignant group. 3. We hope and expect the early detection of breast cancer through the follow-up study in pre-malignant group of mammary dysplasia

  2. Mammographically detected breast arterial calcifications: Indicators for arteriosclerotic diseases?

    International Nuclear Information System (INIS)

    Taskin, Fuesun; Akdilli, Alev; Karaman, Can; Unsal, Alparslan; Koeseoglu, Kutsi; Ergin, Filiz

    2006-01-01

    Purpose: To determine the prevalence of breast arterial calcifications (BAC) detected on mammography and search for conditions that may influence their existence. Materials and methods: The mammograms of 6156 consecutive patients were reevaluated for the presence of BAC. Four hundred eighty-five women having BAC were enrolled in the patient group. Additionally, randomly selected 500 women, without BAC constituted the control group. Hospital records of the participants were reviewed for parity, menopausal status, oral contraceptive agent (OCA) usage, hormone replacement therapy (HRT) usage, presence of diabetes, hypertension, hyperlipidemia, albuminuria and history of myocardial infarction (MI). Results: Prevalence of BAC was 7.9% on mammograms. Ninety-four women were aged between 40 and 49 years, 165 were aged between 50 and 59 years and 226 were over 60 years among BAC positive 485 women. A significant relationship was found for the frequency of BAC versus age and HRT usage in all age groups (p 0.05). Conclusion: Most benign findings like BAC are not routinely reported during mammographic evaluation. Our study showed that, presence of BAC on mammography was strongly related to advancing age. However, these findings may signify a systemic risk and can be used as precautious indicators for undocumented systemic diseases, especially in premenopausal women

  3. EnviroAtlas - Cultivated biological nitrogen fixation in agricultural lands by 12-digit HUC in the Conterminous United States, 2006

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains data on the mean cultivated biological nitrogen fixation (C-BNF) in cultivated crop and hay/pasture lands per 12-digit Hydrologic...

  4. EnviroAtlas - Atmospheric Nitrogen and Sulfur Deposition by 12-digit HUC for the Conterminous United States (2011)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset includes annual nitrogen and sulfur deposition within each 12-digit HUC subwatershed for the year 2011. Values are provided for total...

  5. EnviroAtlas - Synthetic N fertilizer application to agricultural lands by 12-digit HUC in the Conterminous United States, 2006

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains data on the mean synthetic nitrogen (N) fertilizer application to cultivated crop and hay/pasture lands per 12-digit Hydrologic...

  6. 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.

  7. Digital versus analog complete-arch impressions for single-unit premolar implant crowns: Operating time and patient preference.

    Science.gov (United States)

    Schepke, Ulf; Meijer, Henny J A; Kerdijk, Wouter; Cune, Marco S

    2015-09-01

    Digital impression-making techniques are supposedly more patient friendly and less time-consuming than analog techniques, but evidence is lacking to substantiate this assumption. The purpose of this in vivo within-subject comparison study was to examine patient perception and time consumption for 2 complete-arch impression-making methods: a digital and an analog technique. Fifty participants with a single missing premolar were included. Treatment consisted of implant therapy. Three months after implant placement, complete-arch digital (Cerec Omnicam; Sirona) and analog impressions (semi-individual tray, Impregum; 3M ESPE) were made, and the participant's opinion was evaluated with a standard questionnaire addressing several domains (inconvenience, shortness of breath, fear of repeating the impression, and feelings of helplessness during the procedure) with the visual analog scale. All participants were asked which procedure they preferred. Operating time was measured with a stopwatch. The differences between impressions made for maxillary and mandibular implants were also compared. The data were analyzed with paired and independent sample t tests, and effect sizes were calculated. Statistically significant differences were found in favor of the digital procedure regarding all subjective domains (P<.001), with medium to large effect sizes. Of all the participants, over 80% preferred the digital procedure to the analog procedure. The mean duration of digital impression making was 6 minutes and 39 seconds (SD=1:51) versus 12 minutes and 13 seconds (SD=1:24) for the analog impression (P<.001, effect size=2.7). Digital impression making for the restoration of a single implant crown takes less time than analog impression making. Furthermore, participants preferred the digital scan and reported less inconvenience, less shortness of breath, less fear of repeating the impression, and fewer feelings of helplessness during the procedure. Copyright © 2015 Editorial Council

  8. A New Instrument for the Measurement of the Waveform in X-Ray Units

    International Nuclear Information System (INIS)

    Ramirez-Jimenez, Francisco J.; Martinez-Hernandez, Marco A.

    2004-01-01

    The experience gained in the quality control in X-ray units used in Radiology has demonstrated that the measurement of the waveform of the X-ray beam, measured as the response of a radiation detector is very helpful to decide if the unit fulfills the quality control requirements and also has been useful to define some kind of faults in the unit. Several instruments are available on the market to make this measurement but they need in general a storage or digital oscilloscope to see the waveform. In this work a stand alone new instrument is proposed in which the waveform is seen in a Liquid Crystal Display (LCD). The instrument is based in the X-ray response of a photo diode. The analog response depending on time is converted to digital numbers that are stored sequentially in a memory. The stored information is recovered with a microcontroller and reconstructed in the screen of the LCD. The instrument is able to measure in the mammographic range from 22 kV to 35 kV and in the conventional range from 40 kV to 120 kV in the different settings of current encountered on practical applications, the time range for the measurement of the X-ray shot is from 100 ms to 3 s. The instrument can be useful in quality control practices and in the verification and maintenance of X-ray units

  9. Comparison of marginal and internal fit of 3-unit ceramic fixed dental prostheses made with either a conventional or digital impression.

    Science.gov (United States)

    Su, Ting-Shu; Sun, Jian

    2016-09-01

    For 20 years, the intraoral digital impression technique has been applied to the fabrication of computer aided design and computer aided manufacturing (CAD-CAM) fixed dental prostheses (FDPs). Clinical fit is one of the main determinants of the success of an FDP. Studies of the clinical fit of 3-unit ceramic FDPs made by means of a conventional impression versus a digital impression technology are limited. The purpose of this in vitro study was to evaluate and compare the internal fit and marginal fit of CAD-CAM, 3-unit ceramic FDP frameworks fabricated from an intraoral digital impression and a conventional impression. A standard model was designed for a prepared maxillary left canine and second premolar and missing first premolar. The model was scanned with an intraoral digital scanner, exporting stereolithography (STL) files as the experimental group (digital group). The model was used to fabricate 10 stone casts that were scanned with an extraoral scanner, exporting STL files to a computer connected to the scanner as the control group (conventional group). The STL files were used to produce zirconia FDP frameworks with CAD-CAM. These frameworks were seated on the standard model and evaluated for marginal and internal fit. Each framework was segmented into 4 sections per abutment teeth, resulting in 8 sections per framework, and was observed using optical microscopy with ×50 magnification. Four measurement points were selected on each section as marginal discrepancy (P1), mid-axial wall (P2), axio-occusal edge (P3), and central-occlusal point (P4). Mean marginal fit values of the digital group (64 ±16 μm) were significantly smaller than those of the conventional group (76 ±18 μm) (Pdigital group (111 ±34 μm) were significantly smaller than those of the conventional group (132 ±44 μm) (Pdigital and conventional impressions showed clinically acceptable marginal and internal fit. The marginal and internal fit of frameworks fabricated from the intraoral

  10. Digital radiography

    International Nuclear Information System (INIS)

    Rath, M.; Lissner, J.; Rienmueller, R.; Haendle, J.; Siemens A.G., Erlangen

    1984-01-01

    Using a prototype of an electronic, universal examination unit equipped with a special X-ray TV installation, spotfilm exposures and digital angiographies with high spatial resolution and wide-range contrast could be made in the clinic for the first time. With transvenous contrast medium injection, the clinical results of digital angiography show excellent image quality in the region of the carotids and renal arteries as well as the arteries of the extremities. The electronic series exposures have an image quality almost comparable to the quality obtained with cutfilm changers in conventional angiography. There are certain limitations due to the input field of 25 cm X-ray image intensified used. In respect of the digital angiography imaging technique, the electronic universal unit is fully suitable for clinical application. (orig.) [de

  11. EnviroAtlas - Percentage of stream and water body shoreline lengths within 30 meters of >= 5% or >= 15% impervious cover by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the percentages of stream and water body shoreline lengths within 30 meters of impervious cover by 12-digit Hydrologic Unit (HUC)...

  12. Mammographic changes in postmenopausal women : comparative effects between continuous combined hormone and single estrogen replacement therapy

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sug; Choi, Jong Tae; Jung, Kyoon Soon; Jung, Seung Hye [Jeil Women' s Hospital, Seoul (Korea, Republic of)

    1997-06-01

    As the use of hormone replacement therapy for the menopausal women increases, some caution is advised, since there is an increased risk of breast cancer. Accordingly, the importance of regular mammography has been addressed. This cross-setional study analyzed the effects of different hormone therapies on mammographic density. Sixty-seven postemenopausal women who had completed one year of hormone therapy and had undergone follow-up mammography, were divided into two groups : Group I : continuous conjugated equine estrogen, 0.625mg, plus continuous medroxyprogesterone acetate, 2.5mg (n=48), Group II : continuous conjugated equine estrogen 0.625mg (n=19). The mammograms were read by two radiologists. With regard to the radiologists involved, interobserver reliabillity (kappa) was 0.70 and intraobserver reliability (kappa) was 0.51 and 0.67. Before hormone therapy, factors related to decreased mammographic density were age and number of full term pregnancies (p<0.05). After one year of hormone therapy, body fat showed a significant increase (p<0.05), but in spite of this, increased mammographic density induced by hormone therapy remained significantly high (p<0.05). Compared with Group II, Group I showed a significant increase in mammographic density (p<0.05). In Group I, mammographic density increased from P2 to DY pattern in two cases, but there was no such change in Group II. The increase of mammographic density seen in Group II was much more significant statistically than that seen in Group I. The mammograms of women who have undergone continuous combined hormone therapy should therefore be interpreted very cautiously.

  13. Mammographic changes in postmenopausal women : comparative effects between continuous combined hormone and single estrogen replacement therapy

    International Nuclear Information System (INIS)

    Oh, Sug; Choi, Jong Tae; Jung, Kyoon Soon; Jung, Seung Hye

    1997-01-01

    As the use of hormone replacement therapy for the menopausal women increases, some caution is advised, since there is an increased risk of breast cancer. Accordingly, the importance of regular mammography has been addressed. This cross-setional study analyzed the effects of different hormone therapies on mammographic density. Sixty-seven postemenopausal women who had completed one year of hormone therapy and had undergone follow-up mammography, were divided into two groups : Group I : continuous conjugated equine estrogen, 0.625mg, plus continuous medroxyprogesterone acetate, 2.5mg (n=48), Group II : continuous conjugated equine estrogen 0.625mg (n=19). The mammograms were read by two radiologists. With regard to the radiologists involved, interobserver reliabillity (kappa) was 0.70 and intraobserver reliability (kappa) was 0.51 and 0.67. Before hormone therapy, factors related to decreased mammographic density were age and number of full term pregnancies (p<0.05). After one year of hormone therapy, body fat showed a significant increase (p<0.05), but in spite of this, increased mammographic density induced by hormone therapy remained significantly high (p<0.05). Compared with Group II, Group I showed a significant increase in mammographic density (p<0.05). In Group I, mammographic density increased from P2 to DY pattern in two cases, but there was no such change in Group II. The increase of mammographic density seen in Group II was much more significant statistically than that seen in Group I. The mammograms of women who have undergone continuous combined hormone therapy should therefore be interpreted very cautiously

  14. Breast cancer detection using sonography in women with mammographically dense breasts

    International Nuclear Information System (INIS)

    Okello, Jimmy; Kisembo, Harriet; Bugeza, Sam; Galukande, Moses

    2014-01-01

    Mammography, the gold standard for breast cancer screening misses some cancers, especially in women with dense breasts. Breast ultrasonography as a supplementary imaging tool for further evaluation of symptomatic women with mammographically dense breasts may improve the detection of mass lesions otherwise missed at mammography. The purpose of this study was to determine the incremental breast cancer detection rate using US scanning in symptomatic women with mammographically dense breasts in a resource poor environment. A cross sectional descriptive study. Women referred for mammography underwent bilateral breast ultrasound, and mammography for symptom evaluation. The lesions seen by both modalities were described using sonographic BI-RADS lexicon and categorized. Ultrasound guided core biopsies were performed. IRB approval was obtained and all participants provided informed written consent. In total 148 women with mammographically dense breasts were recruited over six months. The prevalence of breast cancer in symptomatic women with mammographically dense breasts was 22/148 (15%). Mammography detected 16/22 (73%) of these cases and missed 6/22 (27%). The six breast cancer cases missed were correctly diagnosed on breast ultrasonography. Sonographic features typical of breast malignancy were irregular shape, non-parallel orientation, non circumscribed margin, echogenic halo, and increased lesion vascularity (p values < 0.005). Typical sonofeatures of benign mass lesions were: oval shape, parallel orientation and circumscribed margin (p values <0.005). Breast ultrasound scan as a supplementary imaging tool detected 27% more malignant mass lesions otherwise missed by mammography among these symptomatic women with mammographically dense breasts. We recommend that ultra sound scanning in routine evaluation of symptomatic women with mammographically dense breasts

  15. Background risk of breast cancer and the association between physical activity and mammographic density.

    Science.gov (United States)

    Trinh, Thang; Eriksson, Mikael; Darabi, Hatef; Bonn, Stephanie E; Brand, Judith S; Cuzick, Jack; Czene, Kamila; Sjölander, Arvid; Bälter, Katarina; Hall, Per

    2015-04-02

    High physical activity has been shown to decrease the risk of breast cancer, potentially by a mechanism that also reduces mammographic density. We tested the hypothesis that the risk of developing breast cancer in the next 10 years according to the Tyrer-Cuzick prediction model influences the association between physical activity and mammographic density. We conducted a population-based cross-sectional study of 38,913 Swedish women aged 40-74 years. Physical activity was assessed using the validated web-questionnaire Active-Q and mammographic density was measured by the fully automated volumetric Volpara method. The 10-year risk of breast cancer was estimated using the Tyrer-Cuzick (TC) prediction model. Linear regression analyses were performed to assess the association between physical activity and volumetric mammographic density and the potential interaction with the TC breast cancer risk. Overall, high physical activity was associated with lower absolute dense volume. As compared to women with the lowest total activity level (association was seen for any type of physical activity among women with association between total activity and absolute dense volume was modified by the TC breast cancer risk (P interaction = 0.05). As anticipated, high physical activity was also associated with lower non-dense volume. No consistent association was found between physical activity and percent dense volume. Our results suggest that physical activity may decrease breast cancer risk through reducing mammographic density, and that the physical activity needed to reduce mammographic density may depend on background risk of breast cancer.

  16. An analysis of United States K-12 stem education versus STEM workforce at the dawn of the digital revolution

    Science.gov (United States)

    Cataldo, Franca

    The world is at the dawn of a third industrial revolution, the digital revolution, that brings great changes the world over. Today, computing devices, the Internet, and the World Wide Web are vital technology tools that affect every aspect of everyday life and success. While computing technologies offer enormous benefits, there are equally enormous safety and security risks that have been growing exponentially since they became widely available to the public in 1994. Cybercriminals are increasingly implementing sophisticated and serious hack attacks and breaches upon our nation's government, financial institutions, organizations, communities, and private citizens. There is a great need for computer scientists to carry America's innovation and economic growth forward and for cybersecurity professionals to keep our nation safe from criminal hacking. In this digital age, computer science and cybersecurity are essential foundational ingredients of technological innovation, economic growth, and cybersecurity that span all industries. Yet, America's K-12 education institutions are not teaching the computer science and cybersecurity skills required to produce a technologically-savvy 21st century workforce. Education is the key to preparing students to enter the workforce and, therefore, American K-12 STEM education must be reformed to accommodate the teachings required in the digital age. Keywords: Cybersecurity Education, Cybersecurity Education Initiatives, Computer Science Education, Computer Science Education Initiatives, 21 st Century K-12 STEM Education Reform, 21st Century Digital Literacies, High-Tech Innovative Problem-Solving Skills, 21st Century Digital Workforce, Standardized Testing, Foreign Language and Culture Studies, Utica College, Professor Chris Riddell.

  17. Mammographic findings predicting an extensive intraductal component in early stage invasive breast cancer : analysis on microcalcification

    International Nuclear Information System (INIS)

    Kim, Jeong Ah; Kim, Mi Hye; Lee, Mi Kyung; Oh, Ki Keun; Kim, Eun Kyung

    2000-01-01

    To analyze the mammographic findings of extensive intraductal component (EIC)-positive early invasive breast carcinoma and to determine the mammographic features which predict an EIC positivity in an invasive carcinoma. The mammographic and pathologic findings in 71 patients aged 34-79 (mean 50) years in whom stage I or II invasive breast carcinoma had been diagnosed were retrospectively analysed. The mammographic findings were assigned to one of three groups: mass, mass with microcalcification, or microcalcification only. The shape and distribution of a calcification were classified according to the BI-RADS lexicon, and its extent was classified as either more or less than 3 cm. To detect the presence or absence of EIC and the type of ductal carcinoma in situ (DCIS), the findings were re-examined by means of slide mappings. Twenty-eight of 71 patients (39%) showed ECI positivity. The mammographic findings of EIC-positive invasive cancer (n=3D28) were mass with microcalcification (n=3D14), microcalcification only (n=3D7) and mass only (n=3D7). The mammographic finding which predicted EIC positivity was mass with microcalcification (PPV:0.67, NPV:0.33, p=3D0.02). A mammographic of mass only (n=3D39) showed a significantly high negative predictive value for EIC positivity. (PPV 0.18, NPV 0.82, P less than 0.01). A comparison of cases with or without calcification showed that those with microcalcifications (n=3D32) showed a significantly high PPV of 0.66 (NPV:0.34, p less than 0.01) while those without calcification (n=3D39) showed a significantly high NPV of 0.82 (PPV:0.18, p less than 0.01). There were no significant differences in positive predictive values for EIC between the shape, distribution and extent of calcifications. Whenever microcalcification with or without mass is seen on mammographs obtained during early breast cancer, we can predict EIC-positivity, regardless of shape or distribution according to the BI-RADS lexicon. (author)

  18. American College of Radiology Accreditation Program for mammographic screening sites: Physical evaluation criteria

    International Nuclear Information System (INIS)

    Hendrick, R.E.; Haus, A.G.; Hubbard, L.B.; Lasky, H.J.; McCrohan, J.; McLelland, R.; Rothenberg, L.N.; Tanner, R.L.; Zinninger, M.D.

    1987-01-01

    The American College of Radiology has initiated a program for the accreditation of mammographic screening sites, which includes evaluation by mail of image quality and average glandular breast dose. Image quality is evaluated by use of a specially designed phantom (a modified RMI 152D Mammographic Phantom) containing simulated microcalcifications, fibrils and masses. Average glandular dose to a simulated 4.5-cm-thick (50% glandular, 50% fat) compressed breast is evaluated by thermoluminescent dosimeter measurements of entrance exposure and half value layer. Standards for acceptable image quality and patient doses are presented and preliminary results of the accreditation program are discussed

  19. Mammographic and sonographic findings of breast cancer in women younger than 35 years

    International Nuclear Information System (INIS)

    Shaw de Paredes, E.; Marsteller, L.; Eden, B.

    1989-01-01

    Breast carcinoma is uncommon in women under 35 years of age and may be difficult to detect because clinically palpable masses are usually benign, and mammography may be limited by dense parenchyma. The purpose of this work was to evaluate the mammographic findings in young patients with breast cancer and the efficacy of mammography in identifying these lesions. During an 8-year period, 100 breast cancers were diagnosed mammography and sonography were performed in 678% and 19% of patients, respectively; mammography demonstrated the lesion in 90% of cases. Mammographic and sonographic findings are presented

  20. The use of ultrasonography and digital mammography in women under 40 years with symptomatic breast cancer: a 7-year Irish experience.

    Science.gov (United States)

    Redmond, C E; Healy, G M; Murphy, C F; O'Doherty, A; Foster, A

    2017-02-01

    Breast cancer in women under 40 years of age is rare and typically presents symptomatically. The optimal imaging modality for this patient group is controversial. Most women undergo ultrasonography with/without mammography. Young women typically have dense breasts, which can obscure the features of malignancy on film mammography, however, initial studies have suggested that digital mammography may have a more accurate diagnostic performance in younger women. Ultrasound generally performs well in this age group, although it is poor at detecting carcinoma in situ (DCIS). To evaluate the comparative diagnostic performance of ultrasonography and digital mammography in the initial diagnostic evaluation of women under 40 years of age with symptomatic breast cancer. Retrospective review of all women under the age of 40 years managed at our symptomatic breast cancer unit from January 2009 to December 2015. There were 120 patients that met the inclusion criteria for this study. The sensitivity of ultrasonography and digital mammography for breast cancer in this patient group was 95.8 and 87.5 %, respectively. The patients with a false negative mammographic examination were more likely to have dense breasts (p breast cancer in women under the age of 40 years, however, the results show that digital mammography has an important complimentary role in the comprehensive assessment of these patients, particularly in the diagnosis of DCIS.

  1. A study of mammographic appearance of the breast disease

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Kil Ho; Jung, Kyung Hee; Hwang, Mi Soo; Chang, Jae Chun; Kim, Myung Se; Shim, Min Chul; Min, Hyun Sik [College of Medicine, Yeung Nam University, Gyeongsan (Korea, Republic of)

    1985-08-15

    The history of the radiological examination of the breast has been long, and recently the methods for examining the breast are variable: mammography, thermography, xeroradiography, ultrasonography, water-path sonography, transillumination, mammary C.T., M.R imaging, infra-red scanning, nuclear medicine, and galactography. Most of these methods were not proven or have not been satisfied on their clinical testing but conventional mammography has been the gold standard for diagnosis of the breast cancer and no other method has reached its effectiveness. The authors performed mammography in 488 patients with breast abnormalities who had visited to Yeung Nam University hospital from May, 1983 to December, 1984. And we analyzed the mammographic findings and diagnostic accuracy in pathologically confirmed 53 cases by operations or biopsies. The results are as follows: 1. Among 16 cases of breast malignancies (1) the most prevalent age group is 6th decade (37.5%), followed by 5th decade (31.3%), (2) the most common pathologic type is ductal carcinoma (93.75%), (3) the masses are larger than 2cm in 8 cases, smaller than 2cm in 5 cases, and no visible mass is observed in 3 cases. 2. Among 37 cases of benign breast diseases, (1) the most prevalent age group is 4th and 5th decades (each 11 cases), and followed by 3rd decade (8 cases), (2) the most common disease is benign tumor (17 cases), followed by fibrocystic dysplasia (13 cases), and inflammating disease (7 cases), (3) radiologically visible masses are observed in 16 cases and the masses are smaller than 2cm in 11 cases. 3. The diagnostic accuracy of mammography compared with that of pathology, (1) in malignancy, the accuracy rate is 75% (12/16 cases), and 87% (32/37 cases) in benign diseases, (2) average accuracy rate is 81% (44/53 cases)

  2. A study of mammographic appearance of the breast disease

    International Nuclear Information System (INIS)

    Cho, Kil Ho; Jung, Kyung Hee; Hwang, Mi Soo; Chang, Jae Chun; Kim, Myung Se; Shim, Min Chul; Min, Hyun Sik

    1985-01-01

    The history of the radiological examination of the breast has been long, and recently the methods for examining the breast are variable: mammography, thermography, xeroradiography, ultrasonography, water-path sonography, transillumination, mammary C.T., M.R imaging, infra-red scanning, nuclear medicine, and galactography. Most of these methods were not proven or have not been satisfied on their clinical testing but conventional mammography has been the gold standard for diagnosis of the breast cancer and no other method has reached its effectiveness. The authors performed mammography in 488 patients with breast abnormalities who had visited to Yeung Nam University hospital from May, 1983 to December, 1984. And we analyzed the mammographic findings and diagnostic accuracy in pathologically confirmed 53 cases by operations or biopsies. The results are as follows: 1. Among 16 cases of breast malignancies (1) the most prevalent age group is 6th decade (37.5%), followed by 5th decade (31.3%), (2) the most common pathologic type is ductal carcinoma (93.75%), (3) the masses are larger than 2cm in 8 cases, smaller than 2cm in 5 cases, and no visible mass is observed in 3 cases. 2. Among 37 cases of benign breast diseases, (1) the most prevalent age group is 4th and 5th decades (each 11 cases), and followed by 3rd decade (8 cases), (2) the most common disease is benign tumor (17 cases), followed by fibrocystic dysplasia (13 cases), and inflammating disease (7 cases), (3) radiologically visible masses are observed in 16 cases and the masses are smaller than 2cm in 11 cases. 3. The diagnostic accuracy of mammography compared with that of pathology, (1) in malignancy, the accuracy rate is 75% (12/16 cases), and 87% (32/37 cases) in benign diseases, (2) average accuracy rate is 81% (44/53 cases)

  3. Mammographic and Ultrasonographic Findings of the Chemoport Insertion Site

    International Nuclear Information System (INIS)

    Kim, Seun Jung; Kang, Bong Joo; Cha, Eun Suk; Park, Hye Jung; Kim, Sung Hun; Choi, Jae Jeong; Lee, Ji Hye

    2010-01-01

    To describe mammographic and ultrasonographic findings of previous chemoport insertion sites. We included patients who had abnormal findings at chemoport insertion sites on mammography and ultrasonography from 224 patients who underwent chemoport insertion and breast imaging at our institution between January, 2005, and December, 2007. Abnormal findings were identified in 16 mammographies and 14 ultrasonographies in 10 patients. The mean age was 50.9 years and the age range was from 44 to 67 years. Abnormal findings on mammography and ultrasonography were retrospectively analyzed according to ACR/BI-RADS. All cases were followed up with imaging studies for 2 years to confirm changes after chemoport insertion. Of the abnormal findings identified on mammography, focal asymmetry (7/16) was the most common. Other abnormal findings included mass (6/16), skin retraction (2/16), residual chemoport tip (1/16), and trabecular thickening (1/16). Of the abnormal findings seen on ultrasonography, skin thickening (12/14) was the most common. Other abnormal findings included mass (5/14), diffuse increased echogenicity of subcutaneous tissue (1/14), and a localized skin nodule (1/14). Abnormal findings on mammography and ultrasonography were located in the upper outer quadrant in 5 patients, upper inner quadrant in 3 patients, and mid upper portion in 1 patient. In 1 patient, the abnormal finding was only identified in the mediolateral oblique view of her mammography. Radiologists should be aware of potential abnormal findings on mammography and ultrasonography following chemoport insertion. In particular, ultrasonography is a very useful modality for detecting skin complications after chemoport insertion

  4. Relevance analysis of mammographic parenchymal patterns and breast cancer

    International Nuclear Information System (INIS)

    Feng Rendong; Lv Xiangyang; Li Shaolin; Gao Ming; Miao Liqiong

    2009-01-01

    Objective: Discussing the relativity of Mammographic parenchymal patterns and breast cancer, implementing the intervention treatment and regularly traces to the breast high dangerous crowd, in order to reduce the occurrence rate of beast cancer and the mortality rate. Methods: Mammary gland type was marked according to X ray on 500 breast cancer subjects and 1000 control subjects. Peri-cancer histological sections of the subtypes of the breast cancer group and histological section of the subtypes of the control group were studied contrastively to analyze the breast cancer risk index in every subtype and the occurrence rate in every age group. The types and the occurrence rates were counted. Results: (1)The lowest risk group: the subtypes with OR 0.3 and the cancer incidence rate ranging from 5% to 10% were IV b, II b, III b. (4)High-risk group: the subtypes with OR> 1 and the cancer incidence rate above 10% were III c, IV c. High dangerous age sections of breast cancer: 35 to 55 years old in IVc and IIIc (the age section of IIIc may lengthen to 60 years old), 31 to 50 years old in IVb, 50 to 60 years old in IIIb and IIb. Conclusion: IIIc and IVc belong to the high dangerous subtypes. People of these subtypes reach 67.4% of all breast cancer examples, so these people are the main subjects of the mammary gland general survey and tracing. Patient aged from 35 to 55 should be reexamined once a year. When necessary, the intervention treatment may be carried out to prevent breast cancer and to reduce the occurrence rate of beast cancer. Discovery and treatment in early phase can improve the breast cancer's survival quality, and reduce the mortality rate. (authors)

  5. Breast ultrasonographic and histopathological characteristics without any mammographic abnormalities

    International Nuclear Information System (INIS)

    Tamaki, Kentaro; Kamada, Yoshihiko; Uehara, Kano; Tamaki, Nobumitsu; Ishida, Takanori; Miyashita, Minoru; Amari, Masakazu; Ohuchi, Noriaki; Sasano, Hironobu

    2012-01-01

    We evaluated ultrasonographic findings and the corresponding histopathological characteristics of breast cancer patients with Breast Imaging Reporting and Data System (BI-RADS) category 1 mammogram. We retrospectively reviewed the ultrasonographic findings and the corresponding histopathological features of 45 breast cancer patients with BI-RADS category 1 mammogram and 537 controls with mammographic abnormalities. We evaluated the ultrasonographic findings including mass shape, periphery, internal and posterior echo pattern, interruption of mammary borders and the distribution of low-echoic lesions, and the corresponding histopathological characteristics including histological classification, hormone receptor and human epidermal growth factor receptor 2 status of invasive ductal carcinoma and ductal carcinoma in situ, histological grade, mitotic counts and lymphovascular invasion in individual cases of BI-RADS category 1 mammograms and compared with those of the control group. The ultrasonographic characteristics of the BI-RADS category 1 group were characterized by a higher ratio of round shape (P<0.001), non-spiculated periphery (P=0.021), non-interruption of mammary borders (P<0.001) and non-attenuation (P=0.011) compared with the control group. A total of 52.6% of low-echoic lesions were associated with spotted distribution in the BI-RADS 1 group, whereas 25.8% of low-echoic lesions were associated with spotted distribution in the control group (P=0.012). As for histopathological characteristics, there was a statistically higher ratio of triple-negative subtype (P=0.021), and this particular tendency was detected in histological grade 3 in the BI-RADS category 1 group (P=0.094). We evaluated ultrasonographic findings and the corresponding histopathological characteristics for BI-RADS category 1 mammograms and noted significant differences among these findings in this study. Evaluation of these ultrasonographic and histopathological characteristics may provide

  6. Age as a predictive factor of mammographic breast density in Jamaican women

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Deanne; Reid, Marvin; James, Michael

    2002-06-01

    AIM: We sought to determine the relationship between age, and other clinical characteristics such as parity, oestrogen use, dietary factors and menstrual history on breast density in Jamaican women. METHODS AND MATERIALS: A retrospective study was done of 891 patients who attended the breast imaging unit. The clinical characteristics were extracted from the patient records. Mammograms were assessed independently by two radiologists who were blinded to the patient clinical characteristics. Breast densities were assigned using the American College of Radiology (ACR) classification. RESULTS: The concordance between the ACR classification of breast density between the two independent radiologists was 92% with k = 0.76 (SE = 0.02, P < 0.001). Women with low breast density were heavier (81.3 {+-} 15.5 kg vs 68.4 {+-} 14.3 kg,P < 0.0001, mean {+-} standard deviation (SD)) and more obese (body mass index (BMI), 30.3 {+-} 5.8 kg m{sup -2} vs 26.0 {+-} 5.2 kg m{sup -2}, P < 0.0001). Mammographic breast density decreased with age. The age adjusted odds ratios (ORs) for predictors significantly related to high breast density were parity, OR = 0.79 (95%CI:0.71, 0.88), weight, OR = 0.92 (95% CI:0.91, 0.95), BMI, OR = 0.83 (95% CI:0.78, 0.89), menopause, OR = 0.51 (95% CI:0.36, 0.74) and a history of previous breast surgery, OR 1.6 (95% CI:1.1, 2.3). CONCLUSION: The rate decline of breast density with age in our population was influenced by parity and body composition. Soares, D. et al. (2002)

  7. Comparison of subjective and fully automated methods for measuring mammographic density.

    Science.gov (United States)

    Moshina, Nataliia; Roman, Marta; Sebuødegård, Sofie; Waade, Gunvor G; Ursin, Giske; Hofvind, Solveig

    2018-02-01

    Background Breast radiologists of the Norwegian Breast Cancer Screening Program subjectively classified mammographic density using a three-point scale between 1996 and 2012 and changed into the fourth edition of the BI-RADS classification since 2013. In 2015, an automated volumetric breast density assessment software was installed at two screening units. Purpose To compare volumetric breast density measurements from the automated method with two subjective methods: the three-point scale and the BI-RADS density classification. Material and Methods Information on subjective and automated density assessment was obtained from screening examinations of 3635 women recalled for further assessment due to positive screening mammography between 2007 and 2015. The score of the three-point scale (I = fatty; II = medium dense; III = dense) was available for 2310 women. The BI-RADS density score was provided for 1325 women. Mean volumetric breast density was estimated for each category of the subjective classifications. The automated software assigned volumetric breast density to four categories. The agreement between BI-RADS and volumetric breast density categories was assessed using weighted kappa (k w ). Results Mean volumetric breast density was 4.5%, 7.5%, and 13.4% for categories I, II, and III of the three-point scale, respectively, and 4.4%, 7.5%, 9.9%, and 13.9% for the BI-RADS density categories, respectively ( P for trend density categories was k w  = 0.5 (95% CI = 0.47-0.53; P density increased with increasing density category of the subjective classifications. The agreement between BI-RADS and volumetric breast density categories was moderate.

  8. Evaluation of the marginal fit of single-unit, complete-coverage ceramic restorations fabricated after digital and conventional impressions: A systematic review and meta-analysis.

    Science.gov (United States)

    Tsirogiannis, Panagiotis; Reissmann, Daniel R; Heydecke, Guido

    2016-09-01

    the marginal discrepancy of single-unit ceramic restorations fabricated after digital or conventional impressions. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. Fit of 4-unit FDPs made of zirconia and CoCr-alloy after chairside and labside digitalization--a laboratory study.

    Science.gov (United States)

    Keul, Christine; Stawarczyk, Bogna; Erdelt, Kurt-Jürgen; Beuer, Florian; Edelhoff, Daniel; Güth, Jan-Frederik

    2014-04-01

    To analyse the marginal fit of 4-unit fixed dental prostheses (FDPs) and the accuracy of three-dimensional cast-datasets using both approaches to Computer Aided Design (CAD)/Computer Aided Manufacturing (CAM): direct and indirect digitalization. A titanium model of a 4-unit FDP was digitized by an intraoral scanning device (iTero, Align Technology, Carlstadt, US; DD, n=12). Additionally 12 conventional impressions were taken and referring master casts were digitized by a laboratory scanner (CS2, Straumann, Basel, Switzerland; ID, n=12). Frameworks were fabricated (CARES CADCAM GmbH, Straumann, Markkleeberg, Germany) from base metal alloy (coron, Straumann; DD-C: n=12; ID-C: n=12) and zirconia (zerion, Straumann; DD-Z: n=12; ID-Z: n=12) from the same datasets. The marginal fit of the resulting frameworks and the accuracy of the underlying datasets from DD and ID were evaluated. Data were analyzed by unpaired two sample Student's t-test with Levene-test (pdigitalization methods (DD-Z: 127.23±66.87 μm, ID-Z: 141.08±193.17 μm) could be observed. Base metal alloy frameworks exhibited significantly better marginal fit than zirconia frameworks (DD: pdigitalization lead to clinically acceptable marginal fit of 4-unit FDPs from base metal alloy and zirconia. Higher accuracy of datasets from DD leads to better marginal fit of frameworks from base metal alloy but not for ones from zirconia. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  10. Digital versus analog complete-arch impressions for single-unit premolar implant crowns : Operating time and patient preference

    NARCIS (Netherlands)

    Schepke, Ulf; Meijer, Henny J. A.; Kerdijk, Wouter; Cune, Marco S.

    Statement of problem. Digital impression-making techniques are supposedly more patient friendly and less time-consuming than analog techniques, but evidence is lacking to substantiate this assumption. Purpose. The purpose of this in vivo within-subject comparison study was to examine patient

  11. Comparison between the implementation of quality criteria of radiographic image in conventional and digital mammography equipments

    International Nuclear Information System (INIS)

    Alcantara, M.C.; Sordi, G.M.A.A.; Caldas, L.V.E.; Furquim, T.A.C.

    2008-01-01

    The mammographic examination needs a strict quality control. A publication of the European Commission provides guidelines on quality criteria for the images of the breast, quantifying the quality obtained in the image. Following the recommendations of the European Commission, two kinds of mammographic equipments, at a same institution, were evaluated to compare the quality of the conventional and digital images. Besides of that, the Average Glandular Dose (AGD) and the Entrance Surface Dose (ESD) were measured by using an ionization chamber (Radcal, 6M) in the radiation beams of each equipment. The digital equipment fulfills more quality criteria than the conventional equipment, provided ESD values, AGD values and a rejection index lower than the conventional equipment. Therefore, the digital mammography can be considered more adequate than the conventional one, both for criteria analyses and for dose optimization. (author)

  12. Basic digital signal processing

    CERN Document Server

    Lockhart, Gordon B

    1985-01-01

    Basic Digital Signal Processing describes the principles of digital signal processing and experiments with BASIC programs involving the fast Fourier theorem (FFT). The book reviews the fundamentals of the BASIC program, continuous and discrete time signals including analog signals, Fourier analysis, discrete Fourier transform, signal energy, power. The text also explains digital signal processing involving digital filters, linear time-variant systems, discrete time unit impulse, discrete-time convolution, and the alternative structure for second order infinite impulse response (IIR) sections.

  13. Detecting mammographically occult cancer in women with dense breasts using Radon Cumulative Distribution Transform: a preliminary analysis

    Science.gov (United States)

    Lee, Juhun; Nishikawa, Robert M.; Rohde, Gustavo K.

    2018-02-01

    We propose using novel imaging biomarkers for detecting mammographically-occult (MO) cancer in women with dense breast tissue. MO cancer indicates visually occluded, or very subtle, cancer that radiologists fail to recognize as a sign of cancer. We used the Radon Cumulative Distribution Transform (RCDT) as a novel image transformation to project the difference between left and right mammograms into a space, increasing the detectability of occult cancer. We used a dataset of 617 screening full-field digital mammograms (FFDMs) of 238 women with dense breast tissue. Among 238 women, 173 were normal with 2 - 4 consecutive screening mammograms, 552 normal mammograms in total, and the remaining 65 women had an MO cancer with a negative screening mammogram. We used Principal Component Analysis (PCA) to find representative patterns in normal mammograms in the RCDT space. We projected all mammograms to the space constructed by the first 30 eigenvectors of the RCDT of normal cases. Under 10-fold crossvalidation, we conducted quantitative feature analysis to classify normal mammograms and mammograms with MO cancer. We used receiver operating characteristic (ROC) analysis to evaluate the classifier's output using the area under the ROC curve (AUC) as the figure of merit. Four eigenvectors were selected via a feature selection method. The mean and standard deviation of the AUC of the trained classifier on the test set were 0.74 and 0.08, respectively. In conclusion, we utilized imaging biomarkers to highlight differences between left and right mammograms to detect MO cancer using novel imaging transformation.

  14. Fractal analysis of visual search activity for mass detection during mammographic screening.

    Science.gov (United States)

    Alamudun, Folami; Yoon, Hong-Jun; Hudson, Kathleen B; Morin-Ducote, Garnetta; Hammond, Tracy; Tourassi, Georgia D

    2017-03-01

    The objective of this study was to assess the complexity of human visual search activity during mammographic screening using fractal analysis and to investigate its relationship with case and reader characteristics. The study was performed for the task of mammographic screening with simultaneous viewing of four coordinated breast views as typically done in clinical practice. Eye-tracking data and diagnostic decisions collected for 100 mammographic cases (25 normal, 25 benign, 50 malignant) from 10 readers (three board certified radiologists and seven Radiology residents), formed the corpus for this study. The fractal dimension of the readers' visual scanning pattern was computed with the Minkowski-Bouligand box-counting method and used as a measure of gaze complexity. Individual factor and group-based interaction ANOVA analysis was performed to study the association between fractal dimension, case pathology, breast density, and reader experience level. The consistency of the observed trends depending on gaze data representation was also examined. Case pathology, breast density, reader experience level, and individual reader differences are all independent predictors of the complexity of visual scanning pattern when screening for breast cancer. No higher order effects were found to be significant. Fractal characterization of visual search behavior during mammographic screening is dependent on case properties and image reader characteristics. © 2017 American Association of Physicists in Medicine.

  15. Birth weight, childhood body mass index, and height in relation to mammographic density and breast cancer

    DEFF Research Database (Denmark)

    Andersen, Zorana Jovanovic; Baker, Jennifer Lyn; Bihrmann, Kristine

    2014-01-01

    High breast density, a strong predictor of breast cancer may be determined early in life. Childhood anthropometric factors have been related to breast cancer and breast density, but rarely simultaneously. We examined whether mammographic density (MD) mediates an association of birth weight, child...

  16. International Consortium on Mammographic Density : Methodology and population diversity captured across 22 countries

    NARCIS (Netherlands)

    McCormack, Valerie A; Burton, Anya; Dos-Santos-Silva, Isabel; Hipwell, John H; Dickens, Caroline; Salem, Dorria; Kamal, Rasha; Hartman, Mikael; Lee, Charmaine Pei Ling; Chia, Kee-Seng; Ozmen, Vahit; Aribal, Mustafa Erkin; Flugelman, Anath Arzee; Lajous, Martín; Lopez-Riduara, Ruy; Rice, Megan; Romieu, Isabelle; Ursin, Giske; Qureshi, Samera; Ma, Huiyan; Lee, Eunjung; van Gils, Carla H; Wanders, Johanna O P; Vinayak, Sudhir; Ndumia, Rose; Allen, Steve; Vinnicombe, Sarah; Moss, Sue; Won Lee, Jong; Kim, Jisun; Pereira, Ana; Garmendia, Maria Luisa; Sirous, Reza; Sirous, Mehri; Peplonska, Beata; Bukowska, Agnieszka; Tamimi, Rulla M; Bertrand, Kimberly; Nagata, Chisato; Kwong, Ava; Vachon, Celine; Scott, Christopher; Perez-Gomez, Beatriz; Pollan, Marina; Maskarinec, Gertraud; Giles, Graham; Hopper, John; Stone, Jennifer; Rajaram, Nadia; Teo, Soo-Hwang; Mariapun, Shivaani; Yaffe, Martin J; Schüz, Joachim; Chiarelli, Anna M; Linton, Linda; Boyd, Norman F

    2015-01-01

    Mammographic density (MD) is a quantitative trait, measurable in all women, and is among the strongest markers of breast cancer risk. The population-based epidemiology of MD has revealed genetic, lifestyle and societal/environmental determinants, but studies have largely been conducted in women with

  17. Immediate and delayed effects of mammographic screening on breast cancer mortality and incidence in birth cohorts

    NARCIS (Netherlands)

    Ripping, T. M.; Verbeek, A. L. M.; van der Waal, D.; Otten, J. D. M.; den Heeten, G. J.; Fracheboud, J.; de Koning, H. J.; Broeders, M. J. M.

    2013-01-01

    Trend studies investigating the impact of mammographic screening usually display age-specific mortality and incidence rates over time, resulting in an underestimate of the benefit of screening, that is, mortality reduction, and an overestimate of its major harmful effect, that is, overdiagnosis.

  18. Immediate and delayed effects of mammographic screening on breast cancer mortality and incidence in birth cohorts

    NARCIS (Netherlands)

    Ripping, T.M.; Verbeek, A.L.M.; Waal, D. van der; Otten, J.D.M.; Heeten, G.J. den; Fracheboud, J.; Koning, H.J. de; Broeders, M.J.M.

    2013-01-01

    Background:Trend studies investigating the impact of mammographic screening usually display age-specific mortality and incidence rates over time, resulting in an underestimate of the benefit of screening, that is, mortality reduction, and an overestimate of its major harmful effect, that is,

  19. Incremental clinical value of ultrasound in men with mammographically confirmed gynecomastia.

    Science.gov (United States)

    Chen, Po-Hao; Slanetz, Priscilla J

    2014-01-01

    To determine whether ultrasound is of any value in male patients presenting with focal symptoms who have classic features of gynecomastia but no concerning findings on mammography. Over a 3-year period, all male patients who underwent mammographic evaluation were identified in this retrospective study. Patients with a mammographic diagnosis of gynecomastia and subsequent breast ultrasound at a large tertiary academic medical center comprised the study cohort. Men whose ultrasound diagnosis differed from the initial mammographic evaluation were analyzed for both additional benign findings as well as findings that warranted biopsy. A total of 353 mammograms were obtained from 327 unique patients (ages 18-95, mean 51 years). Of all mammographic examinations, gynecomastia was the sole finding in 73% (259). In those 259 studies, 85% were further evaluated with ultrasound, in which 6 (2.7%) showed additional benign findings, and 4 (1.8%) showed suspicious findings for which biopsy was recommended. No malignancies were detected in those patients. Furthermore, no malignancies were detected in patients whose mammogram revealed only normal fatty parenchyma or only gynecomastia. In all cases of cancer, mammography revealed visible masses. Judicious use of breast ultrasound in men improves outcome. Our data suggest that targeted ultrasound is of limited value in symptomatic male patients where mammography is negative or reveals only gynecomastia and leads to unnecessary benign biopsies in these patients. When mammography reveals concerning findings, ultrasound adds positively to clinical management. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Incremental clinical value of ultrasound in men with mammographically confirmed gynecomastia

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Po-Hao, E-mail: howard_chen@post.harvard.edu [Harvard Medical School, 25 Shattuck Street, Boston, MA 02115 (United States); Department of Radiology, Hospital of University of Pennsylvania, 3400 Spruce Street, Philadlephia, PA 19104 (United States); Slanetz, Priscilla J., E-mail: pslanetz@bidmc.harvard.edu [Harvard Medical School, 25 Shattuck Street, Boston, MA 02115 (United States); Beth Israel Deaconess Medical Center, Department of Radiology, 330 Brookline Avenue, Boston, MA 02215 (United States)

    2014-01-15

    Purpose: To determine whether ultrasound is of any value in male patients presenting with focal symptoms who have classic features of gynecomastia but no concerning findings on mammography. Materials and Methods: Over a 3-year period, all male patients who underwent mammographic evaluation were identified in this retrospective study. Patients with a mammographic diagnosis of gynecomastia and subsequent breast ultrasound at a large tertiary academic medical center comprised the study cohort. Men whose ultrasound diagnosis differed from the initial mammographic evaluation were analyzed for both additional benign findings as well as findings that warranted biopsy. Results: A total of 353 mammograms were obtained from 327 unique patients (ages 18–95, mean 51 years). Of all mammographic examinations, gynecomastia was the sole finding in 73% (259). In those 259 studies, 85% were further evaluated with ultrasound, in which 6 (2.7%) showed additional benign findings, and 4 (1.8%) showed suspicious findings for which biopsy was recommended. No malignancies were detected in those patients. Furthermore, no malignancies were detected in patients whose mammogram revealed only normal fatty parenchyma or only gynecomastia. In all cases of cancer, mammography revealed visible masses. Conclusion: Judicious use of breast ultrasound in men improves outcome. Our data suggest that targeted ultrasound is of limited value in symptomatic male patients where mammography is negative or reveals only gynecomastia and leads to unnecessary benign biopsies in these patients. When mammography reveals concerning findings, ultrasound adds positively to clinical management.

  1. Residential traffic noise and mammographic breast density in the Diet, Cancer, and Health cohort

    DEFF Research Database (Denmark)

    Roswall, Nina; Andersen, Zorana Jovanovic; von Euler-Chelpin, My

    2018-01-01

    OBJECTIVES: Traffic is the most important source of community noise, and it has been proposed to be associated with a range of disease outcomes, including breast cancer. As mammographic breast density (MD) is one of the strongest risk factors for developing breast cancer, the present study...

  2. Remote Patient Management in a Mammographic Screening Environment in Underserved Areas

    Science.gov (United States)

    2005-09-01

    of 4,945 paired examinations. Radiology 2001; 218:873-880. 10. Malich A, Marx C, Facius M, Boehm T, Fleck M, Kaiser WA. Tumour 24. Venta LA, Hendrick...218:873-880. KF, Sickles EA. Mammographic character- factor determining the quality of com- 15. Venta LA, Hendrick RE, Adler YT, et al. iSicks of 115

  3. Ethnic differences in mammographic densities: an Asian cross-sectional study.

    Science.gov (United States)

    Mariapun, Shivaani; Li, Jingmei; Yip, Cheng Har; Taib, Nur Aishah Mohd; Teo, Soo-Hwang

    2015-01-01

    Mammographic density is a strong risk factor for breast cancer and is highly variable, but, to date, few studies have examined density in Asian women, particularly those in low and middle-income Asian countries where genetic and lifestyle determinants may be significantly different. A total of 1,240 women who attended an opportunistic mammogram screening programme were eligible for analysis. Mammographic density was estimated using a fully-automated thresholding method and differences across ethnic groups were examined using linear regression in 205 randomly selected Chinese women, 138 Malay and 199 Indian women. Percent density was significantly higher in Chinese women (28.5%; 95% CI 27.0%, 30.0%) compared to Malay (24.2%; 95% CI 22.5%, 26.0%) and Indian (24.3%; 95% CI 22.8%, 25.7%) women (pChinese (72.2cm2; 95% CI 67.9cm2, 76.5cm2) women compared to Malay (92.1cm2; 95% CI 86.9cm2, 97.2cm2) and Indian (97.7cm2; 95% CI 93.4cm2, 101.9cm2) women (pChinese compared to Malay and Indian women in Malaysia. Known lifestyle determinants of mammographic density do not fully account for the ethnic variations observed in mammographic density in this Asian cohort.

  4. Resolution effects on the morphology of calcifications in digital mammograms

    Energy Technology Data Exchange (ETDEWEB)

    Kallergi, Maria; He, Li; Gavrielides, Marios; Heine, John; Clarke, Laurence P [Department of Radiology, College of Medicine, and H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida, 12901 Bruce B. Downs Blvd., Box 17, Tampa, FL 33612 (United States)

    1999-12-31

    The development of computer assisted diagnosis (CAD) techniques and direct digital mammography systems have generated significant interest in the issue of the effect of image resolution on the detection and classification (benign vs malignant) of mammographic abnormalities. CAD in particular seems to heavily depend on image resolution, either due to the inherent algorithm design and optimization, which is almost always dependent, or due to the differences in image content at the various resolutions. This twofold dependence makes it even more difficult to answer the question of what is the minimum resolution required for successful detection and/or classification of a specific mammographic abnormality, such as calcifications. One may begin by evaluating the losses in the mammograms as the films are digitized with different pixel sizes and depths. In this paper we attempted to measure these losses for the case of calcifications at four different spatial resolutions through a simulation model and a classification scheme that is based only on morphological features. The results showed that a 60 {mu}m pixel size and 12 bits per pixel should at least be used if the morphology and distribution of the calcifications are essential components in the CAD algorithm design. These conclusions were tested with the use of a wavelet-based algorithm for the segmentation of simulated mammographic calcifications at various resolutions. The evaluation of the segmentation through shape analysis and classification supported the initial conclusion. (authors) 14 refs., 1 tabs.

  5. Functional needs which led to the use of digital computing devices in the protection system of 1300 MW units

    International Nuclear Information System (INIS)

    Dalle, H.

    1986-01-01

    After a review of classical protection functions used in 900 MW power plants, it is concluded that in order to have functioning margins it is useful to calculate more finely the controled parameters. These calculating needs lead to the use of digital computing devices. Drawing profit from the new possibilities one can improve the general performances of the protection system with regard to availability, safety and maintenance. These options in the case of PALUEL led to the realization of SPIN, described here

  6. Development of a prototype chest digital tomosynthesis (CDT) R/F system with fast image reconstruction using graphics processing unit (GPU) programming

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sunghoon, E-mail: choi.sh@yonsei.ac.kr [Department of Radiological Science, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of); Lee, Seungwan [Department of Radiological Science, College of Medical Science, Konyang University, 158 Gwanjeodong-ro, Daejeon, 308-812 (Korea, Republic of); Lee, Haenghwa [Department of Radiological Science, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of); Lee, Donghoon; Choi, Seungyeon [Department of Radiation Convergence Engineering, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of); Shin, Jungwook [LISTEM Corporation, 94 Donghwagongdan-ro, Munmak-eup, Wonju (Korea, Republic of); Seo, Chang-Woo [Department of Radiological Science, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of); Kim, Hee-Joung, E-mail: hjk1@yonsei.ac.kr [Department of Radiological Science, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of); Department of Radiation Convergence Engineering, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of)

    2017-03-11

    Digital tomosynthesis offers the advantage of low radiation doses compared to conventional computed tomography (CT) by utilizing small numbers of projections (~80) acquired over a limited angular range. It produces 3D volumetric data, although there are artifacts due to incomplete sampling. Based upon these characteristics, we developed a prototype digital tomosynthesis R/F system for applications in chest imaging. Our prototype chest digital tomosynthesis (CDT) R/F system contains an X-ray tube with high power R/F pulse generator, flat-panel detector, R/F table, electromechanical radiographic subsystems including a precise motor controller, and a reconstruction server. For image reconstruction, users select between analytic and iterative reconstruction methods. Our reconstructed images of Catphan700 and LUNGMAN phantoms clearly and rapidly described the internal structures of phantoms using graphics processing unit (GPU) programming. Contrast-to-noise ratio (CNR) values of the CTP682 module of Catphan700 were higher in images using a simultaneous algebraic reconstruction technique (SART) than in those using filtered back-projection (FBP) for all materials by factors of 2.60, 3.78, 5.50, 2.30, 3.70, and 2.52 for air, lung foam, low density polyethylene (LDPE), Delrin{sup ®} (acetal homopolymer resin), bone 50% (hydroxyapatite), and Teflon, respectively. Total elapsed times for producing 3D volume were 2.92 s and 86.29 s on average for FBP and SART (20 iterations), respectively. The times required for reconstruction were clinically feasible. Moreover, the total radiation dose from our system (5.68 mGy) was lower than that of conventional chest CT scan. Consequently, our prototype tomosynthesis R/F system represents an important advance in digital tomosynthesis applications.

  7. External validation of a publicly available computer assisted diagnostic tool for mammographic mass lesions with two high prevalence research datasets.

    Science.gov (United States)

    Benndorf, Matthias; Burnside, Elizabeth S; Herda, Christoph; Langer, Mathias; Kotter, Elmar

    2015-08-01

    Lesions detected at mammography are described with a highly standardized terminology: the breast imaging-reporting and data system (BI-RADS) lexicon. Up to now, no validated semantic computer assisted classification algorithm exists to interactively link combinations of morphological descriptors from the lexicon to a probabilistic risk estimate of malignancy. The authors therefore aim at the external validation of the mammographic mass diagnosis (MMassDx) algorithm. A classification algorithm like MMassDx must perform well in a variety of clinical circumstances and in datasets that were not used to generate the algorithm in order to ultimately become accepted in clinical routine. The MMassDx algorithm uses a naïve Bayes network and calculates post-test probabilities of malignancy based on two distinct sets of variables, (a) BI-RADS descriptors and age ("descriptor model") and (b) BI-RADS descriptors, age, and BI-RADS assessment categories ("inclusive model"). The authors evaluate both the MMassDx (descriptor) and MMassDx (inclusive) models using two large publicly available datasets of mammographic mass lesions: the digital database for screening mammography (DDSM) dataset, which contains two subsets from the same examinations-a medio-lateral oblique (MLO) view and cranio-caudal (CC) view dataset-and the mammographic mass (MM) dataset. The DDSM contains 1220 mass lesions and the MM dataset contains 961 mass lesions. The authors evaluate discriminative performance using area under the receiver-operating-characteristic curve (AUC) and compare this to the BI-RADS assessment categories alone (i.e., the clinical performance) using the DeLong method. The authors also evaluate whether assigned probabilistic risk estimates reflect the lesions' true risk of malignancy using calibration curves. The authors demonstrate that the MMassDx algorithms show good discriminatory performance. AUC for the MMassDx (descriptor) model in the DDSM data is 0.876/0.895 (MLO/CC view) and AUC

  8. Bilateral mammographic density asymmetry and breast cancer risk: A preliminary assessment

    International Nuclear Information System (INIS)

    Zheng, Bin; Sumkin, Jules H.; Zuley, Margarita L.; Wang, Xingwei; Klym, Amy H.; Gur, David

    2012-01-01

    To improve efficacy of breast cancer screening and prevention programs, it requires a risk assessment model with high discriminatory power. This study aimed to assess classification performance of using computed bilateral mammographic density asymmetry to predict risk of individual women developing breast cancer in near-term. The database includes 451 cases with multiple screening mammography examinations. The first (baseline) examinations of all case were interpreted negative. In the next sequential examinations, 187 cases developed cancer or surgically excised high-risk lesions, 155 remained negative (not-recalled), and 109 were recalled benign cases. From each of two bilateral cranio-caudal view images acquired from the baseline examination, we computed two features of average pixel value and local pixel value fluctuation. We then computed mean and difference of each feature computed from two images. When applying the computed features and other two risk factors (woman's age and subjectively rated mammographic density) to predict risk of cancer development, areas under receiver operating characteristic curves (AUC) were computed to evaluate the discriminatory/classification performance. The AUCs are 0.633 ± 0.030, 0.535 ± 0.036, 0.567 ± 0.031, and 0.719 ± 0.027 when using woman's age, subjectively rated, computed mean and asymmetry of mammographic density, to classify between two groups of cancer-verified and negative cases, respectively. When using an equal-weighted fusion method to combine woman's age and computed density asymmetry, AUC increased to 0.761 ± 0.025 (p < 0.05). The study demonstrated that bilateral mammographic density asymmetry could be a significantly stronger risk factor associated to the risk of women developing breast cancer in near-term than woman's age and assessed mean mammographic density.

  9. Size, node status and grade of breast tumours: association with mammographic parenchymal patterns

    Energy Technology Data Exchange (ETDEWEB)

    Sala, E.; Solomon, L.; McCann, J. [Department of Community Medicine, Strangeways Research Laboratory, Worts Causeway, Cambridge (United Kingdom); Warren, R. [Cambridge and Huntingdon Breast Screening Service, Rosie Maternity Hospital, Robinson Way, Cambridge (United Kingdom); Duffy, S. [MRC-Biostatistics Unit, Institute of Public Health, Cambridge (United Kingdom); Luben, R. [Department of Clinical Gerontology, Strangeways Research Laboratory, Cambridge (United Kingdom); Day, N. [Department of Community Medicine, Institute of Public Health, Robinson Way, Cambridge, CB2 2SR (United Kingdom)

    2000-01-01

    A case-control study was designed to assess the association of mammographic parenchymal patterns with the risk of in-situ and invasive breast cancer. In addition, the relationship between tumour characteristics and mammographic patterns were also investigated. A total of 875 patients with breast cancer were selected and matched with 2601 controls. Mammographic parenchymal patterns of breast tissue were assessed according to Wolfe's classification, and statistical analysis was by conditional logistic regression. Relative to the N1 pattern, the odds ratios of having an invasive breast cancer associated with the P2 and DY patterns were 1.8 and 1.4, respectively. In addition, the odd ratios of having an invasive grade 3 breast cancer associated with the P2 and DY patterns were 2.8 and 3.9, respectively. Relative to the combined N1/P1 pattern, the odd ratios of having a breast cancer smaller than 14 mm, 15-29 mm, or larger than 30 mm associated with the combined high-risk P2/DY pattern (P2 + DY) were 1.2, 1.6, and 2.0, respectively. Finally, women with the P2/DY pattern were twice as likely to have a breast cancer which had already spread to the axillary nodes, compared to women with women with the N1/P1 pattern (odds ratios of 2.1 and 1.4, respectively). Our results confirm previous findings suggesting that mammographic parenchymal patterns may serve as indicators of risk for breast cancer. Our results also suggest that mammographic parenchymal patterns are associated with the stage at which breast cancer is detected. (orig.)

  10. Bilateral mammographic density asymmetry and breast cancer risk: A preliminary assessment

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Bin, E-mail: zhengb@upmc.edu [Department of Radiology, University of Pittsburgh, 3362 Fifth Ave, Pittsburgh, PA 15213 (United States); Sumkin, Jules H., E-mail: jsumkin@mail.magee.edu [Department of Radiology, Magee Womens Hospital, 300 Halket Street, Pittsburgh, PA 15213 (United States); Zuley, Margarita L., E-mail: zuleyml@upmc.edu [Department of Radiology, Magee Womens Hospital, 300 Halket Street, Pittsburgh, PA 15213 (United States); Wang, Xingwei, E-mail: wangx6@upmc.edu [Department of Radiology, University of Pittsburgh, 3362 Fifth Ave, Pittsburgh, PA 15213 (United States); Klym, Amy H., E-mail: klymah@upmc.edu [Department of Radiology, University of Pittsburgh, 3362 Fifth Ave, Pittsburgh, PA 15213 (United States); Gur, David, E-mail: gurd@upmc.edu [Department of Radiology, University of Pittsburgh, 3362 Fifth Ave, Pittsburgh, PA 15213 (United States)

    2012-11-15

    To improve efficacy of breast cancer screening and prevention programs, it requires a risk assessment model with high discriminatory power. This study aimed to assess classification performance of using computed bilateral mammographic density asymmetry to predict risk of individual women developing breast cancer in near-term. The database includes 451 cases with multiple screening mammography examinations. The first (baseline) examinations of all case were interpreted negative. In the next sequential examinations, 187 cases developed cancer or surgically excised high-risk lesions, 155 remained negative (not-recalled), and 109 were recalled benign cases. From each of two bilateral cranio-caudal view images acquired from the baseline examination, we computed two features of average pixel value and local pixel value fluctuation. We then computed mean and difference of each feature computed from two images. When applying the computed features and other two risk factors (woman's age and subjectively rated mammographic density) to predict risk of cancer development, areas under receiver operating characteristic curves (AUC) were computed to evaluate the discriminatory/classification performance. The AUCs are 0.633 {+-} 0.030, 0.535 {+-} 0.036, 0.567 {+-} 0.031, and 0.719 {+-} 0.027 when using woman's age, subjectively rated, computed mean and asymmetry of mammographic density, to classify between two groups of cancer-verified and negative cases, respectively. When using an equal-weighted fusion method to combine woman's age and computed density asymmetry, AUC increased to 0.761 {+-} 0.025 (p < 0.05). The study demonstrated that bilateral mammographic density asymmetry could be a significantly stronger risk factor associated to the risk of women developing breast cancer in near-term than woman's age and assessed mean mammographic density.

  11. Size, node status and grade of breast tumours: association with mammographic parenchymal patterns

    International Nuclear Information System (INIS)

    Sala, E.; Solomon, L.; McCann, J.; Warren, R.; Duffy, S.; Luben, R.; Day, N.

    2000-01-01

    A case-control study was designed to assess the association of mammographic parenchymal patterns with the risk of in-situ and invasive breast cancer. In addition, the relationship between tumour characteristics and mammographic patterns were also investigated. A total of 875 patients with breast cancer were selected and matched with 2601 controls. Mammographic parenchymal patterns of breast tissue were assessed according to Wolfe's classification, and statistical analysis was by conditional logistic regression. Relative to the N1 pattern, the odds ratios of having an invasive breast cancer associated with the P2 and DY patterns were 1.8 and 1.4, respectively. In addition, the odd ratios of having an invasive grade 3 breast cancer associated with the P2 and DY patterns were 2.8 and 3.9, respectively. Relative to the combined N1/P1 pattern, the odd ratios of having a breast cancer smaller than 14 mm, 15-29 mm, or larger than 30 mm associated with the combined high-risk P2/DY pattern (P2 + DY) were 1.2, 1.6, and 2.0, respectively. Finally, women with the P2/DY pattern were twice as likely to have a breast cancer which had already spread to the axillary nodes, compared to women with women with the N1/P1 pattern (odds ratios of 2.1 and 1.4, respectively). Our results confirm previous findings suggesting that mammographic parenchymal patterns may serve as indicators of risk for breast cancer. Our results also suggest that mammographic parenchymal patterns are associated with the stage at which breast cancer is detected. (orig.)

  12. Establishment of quality assessment standard for mammographic equipment: evaluation of phantom and clinical images

    International Nuclear Information System (INIS)

    Lee, Sung Hoon; Choe, Yeon Hyeon; Chung, Soo Young

    2005-01-01

    The purpose of this study was to establish a quality standard for mammographic equipment Korea and to eventually improve mammographic quality in clinics and hospitals throughout Korea by educating technicians and clinic personnel. For the phantom test and on site assessment, we visited 37 sites and examined 43 sets of mammographic equipment. Items that were examined include phantom test, radiation dose measurement, developer assessment, etc. The phantom images were assessed visually and by optical density measurements. For the clinical image assessment, clinical images from 371 sites were examined following the new Korean standard for clinical image evaluation. The items examined include labeling, positioning, contrast, exposure, artifacts, collimation among others. Quality standard of mammographic equipment was satisfied in all equipment on site visits. Average mean glandular dose was 114.9 mRad. All phantom image test scores were over 10 points (average, 10.8 points). However, optical density measurements were below 1.2 in 9 sets of equipment (20.9%). Clinical image evaluation revealed appropriate image quality in 83.5%, while images from non-radiologist clinics were adequate in 74.6% (91/122), which was the lowest score of any group. Images were satisfactory in 59.0% (219/371) based on evaluation by specialists following the new Korean standard for clinical image evaluation. Satisfactory images had a mean score of 81.7 (1 S.D. =8.9) and unsatisfactory images had a mean score of 61.9 (1 S.D = 11). The correlation coefficient between the two observers was 0.93 (ρ < 0.01) in 49 consecutive cases. The results of the phantom tests suggest that optical density measurements should be performed as part of a new quality standard for mammographic equipment. The new clinical evaluation criteria that was used in this study can be implemented with some modifications for future mammography quality control by the Korean government

  13. Development of new process network for gas chromatograph and analyzers connected with SCADA system and Digital Control Computers at Cernavoda NPP Unit 1

    International Nuclear Information System (INIS)

    Deneanu, Cornel; Popa Nemoiu, Dragos; Nica, Dana; Bucur, Cosmin

    2007-01-01

    The continuous monitoring of gas mixture concentrations (deuterium/ hydrogen/oxygen/nitrogen) accumulated in 'Moderator Cover Gas', 'Liquid Control Zone' and 'Heat Transport D 2 O Storage Tank Cover Gas', as well as the continuous monitoring of Heavy Water into Light Water concentration in 'Boilers Steam', 'Boilers Blown Down', 'Moderator heat exchangers', and 'Recirculated Water System', sensing any leaks of Cernavoda NPP U1 led to requirement of developing a new process network for gas chromatograph and analyzers connected to the SCADA system and Digital Control Computers of Cernavoda NPP Unit 1. In 2005 it was designed and implemented the process network for gas chromatograph which connected the gas chromatograph equipment to the SCADA system and Digital Control Computers of the Cernavoda NPP Unit 1. Later this process network for gas chromatograph has been extended to connect the AE13 and AE14 Fourier Transform Infrared (FTIR) analyzers with either. The Gas Chromatograph equipment measures with best accuracy the mixture gases (deuterium/ hydrogen/oxygen/nitrogen) concentration. The Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers measure the Heavy Water into Light Water concentration in Boilers Steam, Boilers BlownDown, Moderator heat exchangers, and Recirculated Water System, monitoring and signaling any leaks. The Gas Chromatograph equipment and Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers use the new OPC (Object Link Embedded for Process Control) technologies available in ABB's VistaNet network for interoperability with automation equipment. This new process network has interconnected the ABB chromatograph and Fourier Transform Infrared analyzers with plant Digital Control Computers using new technology. The result was an increased reliability and capability for inspection and improved system safety

  14. Digital broadcasting

    International Nuclear Information System (INIS)

    Park, Ji Hyeong

    1999-06-01

    This book contains twelve chapters, which deals with digitization of broadcast signal such as digital open, digitization of video signal and sound signal digitization of broadcasting equipment like DTPP and digital VTR, digitization of equipment to transmit such as digital STL, digital FPU and digital SNG, digitization of transmit about digital TV transmit and radio transmit, digital broadcasting system on necessity and advantage, digital broadcasting system abroad and Korea, digital broadcasting of outline, advantage of digital TV, ripple effect of digital broadcasting and consideration of digital broadcasting, ground wave digital broadcasting of DVB-T in Europe DTV in U.S.A and ISDB-T in Japan, HDTV broadcasting, satellite broadcasting, digital TV broadcasting in Korea, digital radio broadcasting and new broadcasting service.

  15. Evidentiary Power and Propriety of Digital Identifiers and the Impact on Privacy Rights in the United States

    Directory of Open Access Journals (Sweden)

    Michael Losavio

    2014-09-01

    Full Text Available Media and network systems capture and store data about electronic activity in new, sometimes unprecedented ways; computational systems make for new means of analysis and knowledge development. These new forms offer new, powerful tactical tools for investigations of electronic malfeasance under traditional legal regulation of state power, particular that of Fourth Amendment limitations on police searches and seizures under the U.S. Constitution. But autonomy, identity and authenticity concerns with electronic data raise issues of public policy, privacy and proper police oversight of civil society. We examine those issues and their implications for digital and computational forensics.

  16. EnviroAtlas - Inorganic phosphorus fertilizer application for 2012 by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas national map displays the application rate of inorganic phosphorus (P) fertilizer on agricultural land in the conterminous United States (excluding...

  17. EnviroAtlas - Phosphorus application as manure for 2012 by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas national map displays the application rate of phosphorus (P) as manure on croplands in the conterminous United States (excluding Hawaii and Alaska)...

  18. EnviroAtlas - Crop phosphorus removal by 12-digit HUC for 2012 for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas national map displays the mean crop phosphorus (P) removal from croplands in the conterminous United States (excluding Hawaii and Alaska) for the...

  19. Common Input to Motor Units of Intrinsic and Extrinsic Hand Muscles During Two-Digit Object Hold

    OpenAIRE

    Winges, Sara A.; Kornatz, Kurt W.; Santello, Marco

    2008-01-01

    Anatomical and physiological evidence suggests that common input to motor neurons of hand muscles is an important neural mechanism for hand control. To gain insight into the synaptic input underlying the coordination of hand muscles, significant effort has been devoted to describing the distribution of common input across motor units of extrinsic muscles. Much less is known, however, about the distribution of common input to motor units belonging to different intrinsic muscles and to intrinsi...

  20. Geospatial compilation and digital map of centerpivot irrigated areas in the mid-Atlantic region, United States

    Science.gov (United States)

    Finkelstein, Jason S.; Nardi, Mark R.

    2015-01-01

    To evaluate water availability within the Northern Atlantic Coastal Plain, the U.S. Geological Survey, in cooperation with the University of Delaware Agricultural Extension, created a dataset that maps the number of acres under center-pivot irrigation in the Northern Atlantic Coastal Plain study area. For this study, the extent of the Northern Atlantic Coastal Plain falls within areas of the States of New York, New Jersey, Delaware, Maryland, Virginia, and North Carolina. The irrigation dataset maps about 271,900 acres operated primarily under center-pivot irrigation in 57 counties. Manual digitizing was performed against aerial imagery in a process where operators used observable center-pivot irrigation signatures—such as irrigation arms, concentric wheel paths through cropped areas, and differential colors—to identify and map irrigated areas. The aerial imagery used for digitizing came from a variety of sources and seasons. The imagery contained a variety of spatial resolutions and included online imagery from the U.S. Department of Agriculture National Agricultural Imagery Program, Microsoft Bing Maps, and the Google Maps mapping service. The dates of the source images ranged from 2010 to 2012 for the U.S. Department of Agriculture imagery, whereas maps from the other mapping services were from 2013.

  1. Comparative analysis among X-ray mammographic findings, nuclear and histologic grading, and TNM staging of breast carcinoma

    International Nuclear Information System (INIS)

    Park, Jin Sook; Sung, Ki Joon; Cho, Mee Yon; Hong, In Soo; Kim, Myung Soon; Oh, Ki Keun

    1996-01-01

    The purpose of this study was to evaluate the prognosis of breast carcinoma by comparison with X-ray mammographic findings, nuclear and histologic grade, and TNM staging. We retrospectively reviewed 114 cases (113 patients) of breast carcinoma, analysing X-ray mammographic findings of all cases with regard to mass, calcification, and spiculation. In 80 cases of scirrhous invasive ductal breast carcinoma. Black's nuclear and Bloom-Richardson's histologic grade were also evaluated. Mammographic findings and nuclear and histologic grade were compared with TNM staging which might suggest the prognosis of breast carcinoma. X-ray mammographic findings (mass, calcification and spiculation) did not significantly correlate with T staging, but the clinical staging of the spiculation was advanced. These X-ray findings did not significantly correlate with the nuclear grading and the histologic grading. Nuclear grade did not correlate with T and M staging, but correlated significantly with N staging and clinical stage(p < 0.05). Histologic grade did not significantly correlate with TNM staging. The clinical staging of spiculation was advanced and nuclear grade correlated significantly with N stage and clinical staging. X-ray mammographic findings did not directly correlate with nuclear and histologic grading, but combined studies of the evaluation of mammographic findings and nuclear and histologic grade were useful for prognosing breast carcinoma

  2. Microscopy system of atomic force based on a digital optical reading unit and a buzzer-scanner; Sistema de microscopia de fuerza atomica basada en una unidad de lectura optica digital y un escaner-zumbador

    Energy Technology Data Exchange (ETDEWEB)

    Dabirian, R.; Loza M, D. [Universidad de las Fuerzas Armadas-ESPE, Departamento de Ciencias de la Energia y Mecanica, Sangolqui (Ecuador); Wang, W. M.; Hwu, E. T., E-mail: whoand@gmail.com [Academia Sinica, Institute of Physics, Taipei, 11529 Taiwan (China)

    2015-07-01

    An astigmatic detection system (Ads) based on a compact disk/digital-versatile-disk (Cd-DVD) astigmatic optical pickup unit is presented. It can achieve a resolution better than 0.3 nm in detection of the vertical displacement and is able to detect the two-dimensional angular tilt of the object surface. Furthermore, a novel scanner design actuated by piezoelectric disk buzzers is presented. The scanner is composed of a quad-rod actuation structure and several piezoelectric disks. It can be driven directly with low-voltage and low-current sources, such as analogue outputs of a data acquisition card and enables a sufficient scanning range of up to μm. In addition, an economic, high-performance streamlined atomic force microscopy (AFM) was constructed, using the buzzer-scanner to move the sample relative to the probe, and using a Cd/DVD optical pickup unit to detect the mechanical resonance of a micro fabricated cantilever. The performance of the AFM is evaluated. The high sensitivity and high bandwidth of the detection system makes the equipment suitable for characterizing nano scale elements. An AFM using our detection system for detecting the deflection of micro fabricated cantilevers can resolve individual atomic steps on graphite surfaces. (Author)

  3. Delivering digital health and well-being at scale: lessons learned during the implementation of the dallas program in the United Kingdom.

    Science.gov (United States)

    Devlin, Alison M; McGee-Lennon, Marilyn; O'Donnell, Catherine A; Bouamrane, Matt-Mouley; Agbakoba, Ruth; O'Connor, Siobhan; Grieve, Eleanor; Finch, Tracy; Wyke, Sally; Watson, Nicholas; Browne, Susan; Mair, Frances S

    2016-01-01

    To identify implementation lessons from the United Kingdom Delivering Assisted Living Lifestyles at Scale (dallas) program-a large-scale, national technology program that aims to deliver a broad range of digital services and products to the public to promote health and well-being. Prospective, longitudinal qualitative research study investigating implementation processes. Qualitative data collected includes semi-structured e-Health Implementation Toolkit-led interviews at baseline/mid-point (n = 38), quarterly evaluation, quarterly technical and barrier and solutions reports, observational logs, quarterly evaluation alignment interviews with project leads, observational data collected during meetings, and ethnographic data from dallas events (n > 200 distinct pieces of qualitative data). Data analysis was guided by Normalization Process Theory, a sociological theory that aids conceptualization of implementation issues in complex healthcare settings. Five key challenges were identified: 1) The challenge of establishing and maintaining large heterogeneous, multi-agency partnerships to deliver new models of healthcare; 2) The need for resilience in the face of barriers and set-backs including the backdrop of continually changing external environments; 3) The inherent tension between embracing innovative co-design and achieving delivery at pace and at scale; 4) The effects of branding and marketing issues in consumer healthcare settings; and 5) The challenge of interoperability and information governance, when commercial proprietary models are dominant. The magnitude and ambition of the dallas program provides a unique opportunity to investigate the macro level implementation challenges faced when designing and delivering digital health and wellness services at scale. Flexibility, adaptability, and resilience are key implementation facilitators when shifting to new digitally enabled models of care. © The Author 2015. Published by Oxford University Press on behalf of

  4. Delivering digital health and well-being at scale: lessons learned during the implementation of the dallas program in the United Kingdom

    Science.gov (United States)

    Devlin, Alison M; McGee-Lennon, Marilyn; O’Donnell, Catherine A; Bouamrane, Matt-Mouley; Agbakoba, Ruth; O’Connor, Siobhan; Grieve, Eleanor; Finch, Tracy; Wyke, Sally; Watson, Nicholas; Browne, Susan

    2016-01-01

    Objective To identify implementation lessons from the United Kingdom Delivering Assisted Living Lifestyles at Scale (dallas) program—a large-scale, national technology program that aims to deliver a broad range of digital services and products to the public to promote health and well-being. Materials and Methods Prospective, longitudinal qualitative research study investigating implementation processes. Qualitative data collected includes semi-structured e-Health Implementation Toolkit–led interviews at baseline/mid-point (n = 38), quarterly evaluation, quarterly technical and barrier and solutions reports, observational logs, quarterly evaluation alignment interviews with project leads, observational data collected during meetings, and ethnographic data from dallas events (n > 200 distinct pieces of qualitative data). Data analysis was guided by Normalization Process Theory, a sociological theory that aids conceptualization of implementation issues in complex healthcare settings. Results Five key challenges were identified: 1) The challenge of establishing and maintaining large heterogeneous, multi-agency partnerships to deliver new models of healthcare; 2) The need for resilience in the face of barriers and set-backs including the backdrop of continually changing external environments; 3) The inherent tension between embracing innovative co-design and achieving delivery at pace and at scale; 4) The effects of branding and marketing issues in consumer healthcare settings; and 5) The challenge of interoperability and information governance, when commercial proprietary models are dominant. Conclusions The magnitude and ambition of the dallas program provides a unique opportunity to investigate the macro level implementation challenges faced when designing and delivering digital health and wellness services at scale. Flexibility, adaptability, and resilience are key implementation facilitators when shifting to new digitally enabled models of care. PMID:26254480

  5. A CAMAC unit for charge measuring and pulse shape recording based on a fast, 8-bit parallel analog-to-digital converter

    International Nuclear Information System (INIS)

    Kulka, Z.; Kreciejewski, M.; Nadachowski, M.

    1990-08-01

    A device designed mainly for measuring systems for testing parameters of some type of detectors used in the high energy physics is described. The device is one-module CAMAC unit. It is equipped in a fast, 8-bit parallel analog-to-digital converter ''flash''type with a gated integrator at the input and a static RAM (4096 x 8 bit) at the output. The device enables measurements of the charge in pulses from detectors or registration of the shape of these pulses. The construction, operation and parameters of the circuits of the device are described and the way of programming functions using CAMAC dataway is given. 8 refs., 9 figs. (author)

  6. Cigarette smoking and mammographic density in the Danish Diet, Cancer and Health cohort

    DEFF Research Database (Denmark)

    Jacobsen, Katja Kemp; Lynge, Elsebeth; Vejborg, Ilse

    2016-01-01

    with MD. METHODS: For the 5,356 women (4,489 postmenopausal) from the Danish Diet, Cancer and Health cohort (1993-1997) who attended mammographic screening in Copenhagen (1993-2001), we used MD (mixed/dense or fatty) assessed at the first screening after cohort entry. Active smoking (status, duration......PURPOSE: Smoking before first childbirth increases breast cancer risk, but the biological mechanism remains unknown and may involve mammographic density (MD), one of the strongest biomarkers of breast cancer risk. We aimed to examine whether active smoking and passive smoking were associated......, and intensity) and passive smoking were assessed at cohort baseline (1993-1997) via questionnaire, together with other breast cancer risk factors. Logistic regression was used to estimate associations (odds ratios, 95 % confidence intervals) between smoking and MD, adjusting for confounders. RESULTS: Two...

  7. Unsupervised deep learning applied to breast density segmentation and mammographic risk scoring

    DEFF Research Database (Denmark)

    Kallenberg, Michiel Gijsbertus J.; Petersen, Peter Kersten; Nielsen, Mads

    2016-01-01

    Mammographic risk scoring has commonly been automated by extracting a set of handcrafted features from mammograms, and relating the responses directly or indirectly to breast cancer risk. We present a method that learns a feature hierarchy from unlabeled data. When the learned features are used...... as the input to a simple classifier, two different tasks can be addressed: i) breast density segmentation, and ii) scoring of mammographic texture. The proposed model learns features at multiple scales. To control the models capacity a novel sparsity regularizer is introduced that incorporates both lifetime...... and population sparsity. We evaluated our method on three different clinical datasets. Our state-of-the-art results show that the learned breast density scores have a very strong positive relationship with manual ones, and that the learned texture scores are predictive of breast cancer. The model is easy...

  8. Positive predictive value of abnormal mammographic findings and role of assessment procedures

    International Nuclear Information System (INIS)

    Menna, S.; Marra, V.; Di Virgilio, M.R.; Macchia, G.; Frigerio, A.

    1999-01-01

    To investigate the positive predictive value for cancer of abnormal mammographic findings and the role of assessment, the authors reviewed a series of 962 patients recalled and examined in the first breast screening center of Turin (Italy), out of 18996 women aged 50-59 from 1991 to 1995, within a population-based mammography program. The results of this study confirm the accuracy of mammography in the early detection of breast cancer and the different role of assessment procedures in the various abnormal mammographic findings. The improvement in positive predictive value for screening demonstrates the importance of the learning curve within the screening team. Most of this improvement could be referred to refined diagnostic criteria for calcifications [it

  9. Breast calcifications. A standardized mammographic reporting and data system to improve positive predictive value

    International Nuclear Information System (INIS)

    Perugini, G.; Bonzanini, B.; Valentino, C.

    1999-01-01

    The purpose of this work is to investigate the usefulness of a standardized reporting and data system in improving the positive predictive value of mammography in breast calcifications. Using the Breast Imaging Reporting and Data System lexicon developed by the American College of Radiology, it is defined 5 descriptive categories of breast calcifications and classified diagnostic suspicion of malignancy on a 3-grade scale (low, intermediate and high). Two radiologists reviewed 117 mammographic studies selected from those of the patients submitted to surgical biopsy for mammographically detected calcifications from January 1993 to December 1997, and classified them according to the above criteria. The positive predictive value was calculated for all examinations and for the stratified groups. Defining a standardized system for assessing and describing breast calcifications helps improve the diagnostic accuracy of mammography in clinical practice [it

  10. A novel and automatic mammographic texture resemblance marker is an independent risk factor for breast cancer

    DEFF Research Database (Denmark)

    Nielsen, Mads; Karemore, Gopal; Loog, Marco

    2011-01-01

    Objective: We investigated whether breast cancer is predicted by a breast cancer risk mammographic texture resemblance (MTR) marker. Methods: A previously published case-control study included 495 women of which 245 were diagnosed with breast cancer. In baseline mammograms, 2-4 years prior...... to diagnosis, the following mammographic parameters were analysed for relation to breast cancer risk: (C) categorical parenchymal pattern scores; (R) radiologist's percentage density, (P) computer-based percentage density; (H) computer-based breast cancer risk MTR marker; (E) computer-based hormone replacement...... treatment MTR marker; and (A) an aggregate of P and H. Results: Density scores, C, R, and P correlated (tau=0.3-0.6); no other pair of scores showed large (tau>0.2) correlation. For the parameters, the odds ratios of future incidence of breast cancer comparing highest to lowest categories (146 and 106...

  11. Regional trends in breast cancer incidence and mortality in Denmark prior to mammographic screening

    DEFF Research Database (Denmark)

    Andreasen, A H; Andersen, K W; Madsen, Mette

    1994-01-01

    To provide a basis for the evaluation of mammographic screening programmes in Denmark, a study was undertaken of the regional differences in breast cancer incidence and mortality. All 16 regions were followed for the 20 year period, 1970-89, before the start of the first population...... among women below age 60. The mortality was more stable, changing only from 24 to 28 (per 100,000 standardised WSP), but a significant increase occurred in the late 1980s. The study showed regional differences in both incidence and mortality of breast cancer in Denmark. Both the incidence......-based mammographic screening programme in the Copenhagen municipality in 1991. Multiplicative Poisson models were used for the analysis. In general, the incidence increased during this period from 55 to 70 [per 100,000 standardised world standard population (WSP)], and the analysis shows this to be most pronounced...

  12. Citizen Science in the Digital Age: examples of Innovative Projects that are Saving Lives across the United States and Internationally.

    Science.gov (United States)

    Haines-Stiles, G.; Abdalati, W.; Akuginow, E.

    2017-12-01

    Citizen science and crowdsourcing can literally save lives, whether responding to natural or human-caused disasters, and their effectiveness is all the more enhanced when volunteer observers collaborate with professional researchers. The NSF-funded THE CROWD & THE CLOUD public television series premiered on PBS stations in April 2017, and is hosted by former NASA Chief Scientist Waleed Abdalati: it continues streaming at CrowdAndCloud.org. Its four episodes feature examples directly relevant to this session, vividly demonstrating the power and potential of "Citizen Science in the Digital Age." In "Citizens + Scientists" a peer-reviewed journal article, authored by a respected MD but based on Bucket Brigade citizen science data on air quality surrounding oil and gas developments, features prominently in New York State's ban on fracking. In the wake of the Flint disaster, Virginia Tech scientists support community monitoring of lead in Philadelphia's drinking water. Citizens begin to appreciate the arcane scientific and technical details of EPA's Lead and Copper Rule, and STEM is seen to be of vital, daily significance. In "Even Big Data Starts Small" OpenStreetMap volunteers digitize satellite data to help first responders following the devastating 2015 Nepal earthquake, and Public Lab members—enthusiastic Makers and Millennials—fly modified off-the-shelf cameras beneath balloons and kites to track the BP oil spill, continuing their environmental watchdog work up through the present. CoCoRaHS observers (the Community Collaborative Rain, Hail and Snow Network) submit high quality data that has come to be trusted by NOAA's NWS and other federal agencies, enhancing flash flood warnings while project volunteers begin to appreciate the extreme variabity of local weather. Today's citizen science is much more than birds, bees and butterflies, although all those are also being protected by volunteered citizen data that helps shape state and federal conservation policies

  13. Evaluation of the optimum region for mammographic system using computer simulation to study modulation transfer functions

    International Nuclear Information System (INIS)

    Oliveira, Isaura N. Sombra; Schiable, Homero; Porcel, Naider T.; Frere, Annie F.; Marques, Paulo M.A.

    1996-01-01

    An investigation of the 'optimum region' of the radiation field considering mammographic systems is studied. Such a region was defined in previous works as the field range where the system has its best performance and sharpest images. This study is based on a correlation of two methods for evaluating radiologic imaging systems, both using computer simulation in order to determine modulation transfer functions (MTFs) due to the X-ray tube focal spot in several field orientation and locations

  14. Vacuum-assisted breast biopsy of suspected mammographic breast diagnoses: predictive value of serum proteomic profile

    International Nuclear Information System (INIS)

    Schittulli, F.; Ventrella, V.

    2009-01-01

    The project planned a series of actions oriented to different scientific questions: to complete the prospective collection of serum samples for serum proteomic analysis according to SOPs needed for the Italy-USA program; the identification of different mammographic signs for prediction of histological diagnosis of breast lesions through mammotone; the analysis of relationship between serum proteomic profile and micro histology characteristics of breast lesions

  15. Fertility drug use and mammographic breast density in a mammography screening cohort of premenopausal women

    OpenAIRE

    Sprague, Brian L.; Trentham-Dietz, Amy; Terry, Mary Beth; Nichols, Hazel B.; Bersch, Andy J.; Buist, Diana S. M.

    2008-01-01

    The widespread use of ovulation-inducing drugs to enhance fertility has raised concerns regarding potential effects on breast cancer risk, as ovarian stimulation is associated with increases in estrogen and progesterone levels. We investigated the short-term relation between fertility drug use and mammographic breast density, a strong marker of breast cancer risk, among participants in the Group Health Breast Cancer Screening Program. Data linkage with Group Health’s automated pharmacy record...

  16. US and mammographic findings of myofibroblastoma in the female breast: a case report

    International Nuclear Information System (INIS)

    Ko, Seog Wan; Jeon, Soo Bin; Lee, Ji Shin; Kim, Dong Sug

    2005-01-01

    Myofibroblastoma is a rare benign mesenchymal tumor of the breast. It presents as a well circumscribed, solitary nodular mass, and it has been reported to mainly occur in male patients. To our knowledge, few reports have described the radiologic appearance of myofibroblastoma in the female breast and there has been no report from Korea. We describe the mammographic, sonographic and histologic findings of a case of myofibroblastoma that presented as a well defined mass mimicking fibroadenoma in a 44-year-old woman

  17. Prognosis for Mammographically Occult, Early-Stage Breast Cancer Patients Treated With Breast-Conservation Therapy

    International Nuclear Information System (INIS)

    Yang, Tzu-I. J.; Yang Qifeng; Haffty, Bruce G.; Moran, Meena S.

    2010-01-01

    Purpose: To compare mammographically occult (MamOcc) and mammographically positive (MamPos) early-stage breast cancer patients treated with breast-conservation therapy (BCT), to analyze differences between the two cohorts. Methods and Materials: Our two cohorts consisted of 214 MamOcc and 2168 MamPos patients treated with BCT. Chart reviews were conducted to assess mammogram reports and method of detection. All clinical-pathologic and outcome parameters were analyzed to detect differences between the two cohorts. Results: Median follow-up was 7 years. There were no differences in final margins, T stage, nodal status, estrogen/progesterone receptor status, or 'triple-negative' status. Significant differences included younger age at diagnosis (p o histology (p < 0.0001). At 10 years, the differences in overall survival, cause-specific survival, and distant relapse between the two groups did not differ significantly. The MamOcc cohort had more breast relapses (15% vs. 8%; p = 0.0357), but on multivariate analysis this difference was not significant (hazard ratio 1.0, 95% confidence interval 0.993-1.007, p = 0.9296). Breast relapses were mammographically occult in 32% of the MamOcc and 12% of the MamPos cohorts (p = 0.0136). Conclusions: Although our study suggests that there are clinical-pathologic variations for the MamOcc cohort vs. MamPos patients that may ultimately affect management, breast relapse after BCT was not significantly different. Breast recurrences were more often mammographically occult in the MamOcc cohort; consideration should be given to closer follow-up and alternative imaging strategies (ultrasound, breast MRI) for routine posttreatment examination. To our knowledge, this represents the largest series addressing the prognostic significance of MamOcc cancers treated with BCT.

  18. US and mammographic findings of myofibroblastoma in the female breast: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Seog Wan; Jeon, Soo Bin [Chonbuk University Medical College, Jeonju (Korea, Republic of); Lee, Ji Shin [Chonnam University Medicine College, Gwangju (Korea, Republic of); Kim, Dong Sug [Yeungnam University Medicine College, Daegu (Korea, Republic of)

    2005-07-15

    Myofibroblastoma is a rare benign mesenchymal tumor of the breast. It presents as a well circumscribed, solitary nodular mass, and it has been reported to mainly occur in male patients. To our knowledge, few reports have described the radiologic appearance of myofibroblastoma in the female breast and there has been no report from Korea. We describe the mammographic, sonographic and histologic findings of a case of myofibroblastoma that presented as a well defined mass mimicking fibroadenoma in a 44-year-old woman.

  19. 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

  20. Correlation between mammographic findings and corresponding histopathology. Potential predictors for biological characteristics of breast diseases

    International Nuclear Information System (INIS)

    Tamaki, Kentaro; Ishida, Takanori; Miyashita, Minoru; Amari, Masakazu; Ohuchi, Noriaki; Tamaki, Nobumitsu; Sasano, Hironobu

    2011-01-01

    The present study retrospectively evaluated the mammographic findings of 606 Japanese women with breast cancer (median age 50 years; range 27-89 years) and correlated them with histopathological characteristics. Mammographic findings were evaluated with an emphasis on mass shape, margin, density, calcification, and the presence of architectural distortion; these findings were correlated with histopathological characteristics such as intrinsic subtype, histological grade, lymphovascular invasion, and the Ki-67 labeling index. An irregular mass shape and masses with a spiculated margin were significantly higher in the group of patients with luminal A breast cancer than in patients with masses that were lobular or round, or in tumors with an indistinct or microlobulated periphery (P=0.017, P=0.024, P<0.001, and P=0.001, respectively). Irregular mass shape and spiculated periphery were significantly lower in patients with Grade 3 cancer (P<0.001 for both). In terms of lymphovascular invasion, there were significant differences between oval and irregular or round mass shape (P=0.008 and P=0.034), between tumors with a microlobulated and indistinct periphery (P=0.014), between tumors with a punctate and amorphous or pleomorphic calcification shape (P=0.030 and 0.038), and between the presence and absence of architectural distortion (P=0.027). Equivalent or low-density masses were also higher in Grade 1 breast cancers (P=0.007). There were significant differences in the Ki-67 labeling index between irregular and lobular or round tumors (P<0.001 and P=0.014), as well as between spiculated and indistinct or microlobulated tumors (P<0.001 for both). Significant differences were noted in the mammographic features of different primary breast cancer subtypes. These proposed mammographic diagnostic criteria based on biological characteristics may contribute to a more accurate prediction of biological behavior of breast malignancies. (author)

  1. Mammographic quantitative image analysis and biologic image composition for breast lesion characterization and classification

    Energy Technology Data Exchange (ETDEWEB)

    Drukker, Karen, E-mail: kdrukker@uchicago.edu; Giger, Maryellen L.; Li, Hui [Department of Radiology, University of Chicago, Chicago, Illinois 60637 (United States); Duewer, Fred; Malkov, Serghei; Joe, Bonnie; Kerlikowske, Karla; Shepherd, John A. [Radiology Department, University of California, San Francisco, California 94143 (United States); Flowers, Chris I. [Department of Radiology, University of South Florida, Tampa, Florida 33612 (United States); Drukteinis, Jennifer S. [Department of Radiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612 (United States)

    2014-03-15

    Purpose: To investigate whether biologic image composition of mammographic lesions can improve upon existing mammographic quantitative image analysis (QIA) in estimating the probability of malignancy. Methods: The study population consisted of 45 breast lesions imaged with dual-energy mammography prior to breast biopsy with final diagnosis resulting in 10 invasive ductal carcinomas, 5 ductal carcinomain situ, 11 fibroadenomas, and 19 other benign diagnoses. Analysis was threefold: (1) The raw low-energy mammographic images were analyzed with an established in-house QIA method, “QIA alone,” (2) the three-compartment breast (3CB) composition measure—derived from the dual-energy mammography—of water, lipid, and protein thickness were assessed, “3CB alone”, and (3) information from QIA and 3CB was combined, “QIA + 3CB.” Analysis was initiated from radiologist-indicated lesion centers and was otherwise fully automated. Steps of the QIA and 3CB methods were lesion segmentation, characterization, and subsequent classification for malignancy in leave-one-case-out cross-validation. Performance assessment included box plots, Bland–Altman plots, and Receiver Operating Characteristic (ROC) analysis. Results: The area under the ROC curve (AUC) for distinguishing between benign and malignant lesions (invasive and DCIS) was 0.81 (standard error 0.07) for the “QIA alone” method, 0.72 (0.07) for “3CB alone” method, and 0.86 (0.04) for “QIA+3CB” combined. The difference in AUC was 0.043 between “QIA + 3CB” and “QIA alone” but failed to reach statistical significance (95% confidence interval [–0.17 to + 0.26]). Conclusions: In this pilot study analyzing the new 3CB imaging modality, knowledge of the composition of breast lesions and their periphery appeared additive in combination with existing mammographic QIA methods for the distinction between different benign and malignant lesion types.

  2. Ethnic differences in mammographic densities: an Asian cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Shivaani Mariapun

    Full Text Available BACKGROUND: Mammographic density is a strong risk factor for breast cancer and is highly variable, but, to date, few studies have examined density in Asian women, particularly those in low and middle-income Asian countries where genetic and lifestyle determinants may be significantly different. METHODS: A total of 1,240 women who attended an opportunistic mammogram screening programme were eligible for analysis. Mammographic density was estimated using a fully-automated thresholding method and differences across ethnic groups were examined using linear regression in 205 randomly selected Chinese women, 138 Malay and 199 Indian women. RESULTS: Percent density was significantly higher in Chinese women (28.5%; 95% CI 27.0%, 30.0% compared to Malay (24.2%; 95% CI 22.5%, 26.0% and Indian (24.3%; 95% CI 22.8%, 25.7% women (p<0.001, after adjustment for age, BMI, menopausal status, parity and age at first full term pregnancy. Correspondingly, adjusted nondense area was significantly lower in Chinese (72.2cm2; 95% CI 67.9cm2, 76.5cm2 women compared to Malay (92.1cm2; 95% CI 86.9cm2, 97.2cm2 and Indian (97.7cm2; 95% CI 93.4cm2, 101.9cm2 women (p<0.001, but dense area did not differ across the three ethnic groups. CONCLUSIONS: Our study shows that higher percent density and lower nondense area reflect the higher incidence of breast cancer in Chinese compared to Malay and Indian women in Malaysia. Known lifestyle determinants of mammographic density do not fully account for the ethnic variations observed in mammographic density in this Asian cohort.

  3. Ethnic Differences in Mammographic Densities: An Asian Cross-Sectional Study

    Science.gov (United States)

    Mariapun, Shivaani; Li, Jingmei; Yip, Cheng Har; Taib, Nur Aishah Mohd; Teo, Soo-Hwang

    2015-01-01

    Background Mammographic density is a strong risk factor for breast cancer and is highly variable, but, to date, few studies have examined density in Asian women, particularly those in low and middle-income Asian countries where genetic and lifestyle determinants may be significantly different. Methods A total of 1,240 women who attended an opportunistic mammogram screening programme were eligible for analysis. Mammographic density was estimated using a fully-automated thresholding method and differences across ethnic groups were examined using linear regression in 205 randomly selected Chinese women, 138 Malay and 199 Indian women. Results Percent density was significantly higher in Chinese women (28.5%; 95% CI 27.0%, 30.0%) compared to Malay (24.2%; 95% CI 22.5%, 26.0%) and Indian (24.3%; 95% CI 22.8%, 25.7%) women (p<0.001), after adjustment for age, BMI, menopausal status, parity and age at first full term pregnancy. Correspondingly, adjusted nondense area was significantly lower in Chinese (72.2cm2; 95% CI 67.9cm2, 76.5cm2) women compared to Malay (92.1cm2; 95% CI 86.9cm2, 97.2cm2) and Indian (97.7cm2; 95% CI 93.4cm2, 101.9cm2) women (p<0.001), but dense area did not differ across the three ethnic groups. Conclusions Our study shows that higher percent density and lower nondense area reflect the higher incidence of breast cancer in Chinese compared to Malay and Indian women in Malaysia. Known lifestyle determinants of mammographic density do not fully account for the ethnic variations observed in mammographic density in this Asian cohort. PMID:25659139

  4. Rubble-mound breakwater armour units displacement analysis by means of digital images processing methods in scale models

    OpenAIRE

    Courela, J.M.; Carvalho, R.; Lemos, R.; Fortes, C. J. E. M.; Leandro, J.

    2015-01-01

    Rubble-mound structures are commonly used for coastal and port protection and needs a properly design as well as inspection and maintenance during its lifetime. The design of such breakwaters usually requires a physical scale model to be tested under different irregular incident wave and tide conditions in order to evaluate its hydraulic and structural behaviour, namely the stability of the proposed design. Armour units displacement and fall analysis in physical models are then a ...

  5. Easy digital engineering

    International Nuclear Information System (INIS)

    Jin, Dal Bok

    2002-02-01

    This book lists basic of digital engineering, number system and digital code, Boolean algebra and basic logic circuit, simplify of logical expression, combinational circuit, arithmetic circuit, multivibrator circuit, sequential circuit, memory unit of semiconductor and logical element for program, D/A converter and A/D converter, logic element and integrated circuit and logic circuit and micro controller. It has exercises and answers about digital engineering and summary in the end of each chapter.

  6. Mammographic density in asymptomatic menopausal women: correlation with clinical and sonographic findings

    Directory of Open Access Journals (Sweden)

    Beatriz Regina Alvares

    2012-06-01

    Full Text Available OBJECTIVE: To evaluate mammographic breast density in asymptomatic menopausal women in correlation with clinical and sonographic findings. MATERIALS AND METHODS: Mammograms and clinical and sonographic findings of 238 asymptomatic patients were retrospectively reviewed in the period from February/2022 to June/2006. The following variables were analyzed: mammographic density patterns, sonographic findings, patients' age, parity, body mass index and use of hormone replacement therapy. RESULTS: Age, parity and body mass index showed a negative correlation with breast density pattern, while use of hormone replacement therapy showed a positive correlation. Supplementary breast ultrasonography was performed in 103 (43.2% patients. Alterations which could not be visualized at mammography were found in 34 (33% of them, most frequently in women with breast density patterns 3 and 4. CONCLUSION: The authors concluded that breast density patterns were influenced by age, parity, body mass index and time of hormone replacement therapy. Despite not having found any malignant abnormality in the studied cases, the authors have observed a predominance of benign sonographic abnormalities in women with high breast density patterns and without mammographic abnormalities, proving the relevance of supplementary ultrasonography to identify breast lesions in such patients.

  7. Overview of the breast cancer and mammographic status in Asia and in Japan

    International Nuclear Information System (INIS)

    Endo, Tokiko

    2017-01-01

    Breast cancer is the top cancer in women both in the most Western and Asian countries. The incidence of the breast cancer is lower in Asia than in the western countries, but, is increasing due to increase life expectancy, increase urbanization and adoption of western life styles. Mammography screening is the only method that has proved to be effective and cost-effective. In Japan, the mammographic breast cancer screening was started in 2004, and quality control has been done by the Japan Central Organization on Quality Assurance of Breast Cancer Screening, which is consisted with nine major societies concerning the breast cancer diagnosis and treatment. The Japanese Society of Radiological Technology and the Japan Society of Medical Physics are the members of this organization and play impotent roles in mammographic quality control. The main activities of this organization are the education for radiological technicians and interpreters and the insurance the mammographic facilities meet radiation dose and image quality standard. I'll introduce the state of the breast cancer and the efforts for breast cancer screening in Asian countries and in Japan

  8. International Consortium on Mammographic Density: Methodology and Population Diversity captured across 22 Countries

    Science.gov (United States)

    McCormack, Valerie A.; Burton, Anya; dos-Santos-Silva, Isabel; Hipwell, John H.; Dickens, Caroline; Salem, Dorria; Kamal, Rasha; Hartman, Mikael; Ling Lee, Charmaine Pei; Chia, Kee-Seng; Ozmen, Vahit; Aribal, Mustafa Erkin; Flugelman, Anath Arzee; Lajous, Martín; Lopez-Riduara, Ruy; Rice, Megan; Romieu, Isabelle; Ursin, Giske; Qureshi, Samera; Ma, Huiyan; Lee, Eunjung; van Gils, Carla H.; Wanders, Johanna O.P.; Vinayak, Sudhir; Ndumia, Rose; Allen, Steve; Vinnicombe, Sarah; Moss, Sue; Lee, Jong Won; Kim, Jisun; Pereira, Ana; Garmendia, Maria Luisa; Sirous, Reza; Sirous, Mehri; Peplonska, Beata; Bukowska, Agnieszka; Tamimi, Rulla M.; Bertrand, Kimberly; Nagata, Chisato; Kwong, Ava; Vachon, Celine; Scott, Christopher; Perez-Gomez, Beatriz; Pollan, Marina; Maskarinec, Gertraud; Giles, Graham; Hopper, John; Stone, Jennifer; Rajaram, Nadia; Teo, Soo-Hwang; Mariapun, Shivaani; Yaffe, Martin J.; Schüz, Joachim; Chiarelli, Anna; Linton, Linda; Boyd, Norman F.

    2015-01-01

    Mammographic density (MD) is a quantitative trait, measurable in all women, and is among the strongest markers of breast cancer risk. The population-based epidemiology of MD has revealed genetic, lifestyle and societal/environmental determinants, but studies have largely been conducted in women with similar westernized lifestyles living in countries with high breast cancer incidence rates. To benefit from the heterogeneity in risk factors and their combinations worldwide, we created an International Consortium on Mammographic Density (ICMD) to pool individual-level epidemiological and MD data from general population studies worldwide. ICMD aims to characterize determinants of MD more precisely, and to evaluate whether they are consistent across populations worldwide. We included 11755 women, from 27 studies in 22 countries, on whom individual-level risk factor data were pooled and original mammographic images were re-read for ICMD by a core team to obtain standardized comparable MD data. In the present article, we present (i) the rationale for this consortium; (ii) characteristics of the studies and women included; and (iii) study methodology to obtain comparable MD data from original re-read films. We also highlight the risk factor heterogeneity captured by such an effort and, thus, the unique insight the pooled study promises to offer through wider exposure ranges, different confounding structures and enhanced power for sub-group analyses. PMID:26724463

  9. Mammographic features of screening detected pT1 (a–b) invasive breast cancer using BI-RADS lexicon

    Energy Technology Data Exchange (ETDEWEB)

    Bargalló, Xavier, E-mail: xbarga@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Santamaría, Gorane, E-mail: gsanta@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Velasco, Martín, E-mail: mvelasco@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Amo, Montse del, E-mail: mdelamo@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Arguis, Pedro, E-mail: parguis@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Burrel, Marta, E-mail: mburrel@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain); Capurro, Sebastian, E-mail: scapurro@clinic.ub.es [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/Villarroel, 170, 08036 Barcelona (Spain)

    2012-10-15

    Aim: To describe mammographic features in screening detected invasive breast cancer less than or equal to 10 mm using Breast Imaging Reporting and Data System lexicon in full-field digital mammography. Patients and methods: A retrospective analysis of 123 pT1 (a–b) invasive breast cancers in women aged 50–69 years from our screening program. Radiologic patterns were: masses, calcifications, distortions, asymmetries and mixed. Masses: shape, margins and density, and calcifications: morphology, number of flecks and size of the cluster were taken into account, following Breast Imaging Reporting and Data System terminology. Results: We found 61 masses (49.6%), 8 masses with calcifications (6.5%), 30 groups of calcifications (24.4%), 19 architectural distortions (15.4%), 1 architectural distortion with calcifications (0.8%), 4 asymmetries (3.2%). Sixty out of 69 masses were irregular in shape, 6 lobular, 2 ovals and 1 round. Thirty-four showed ill-defined margins, 29 spiculated and 6 microlobulated. Most of them showed a density similar to surrounding fibroglandular tissue. Calcifications were pleomorphic or fine linear in 24 of 30 (80%). Most of cases showed more than 10 flecks and a size greater than 1 cm. Conclusion: The predominant radiologic finding is an irregular, isodense mass those margins tend to share different descriptors, being ill-defined margins the most constant finding. Calcifications representing invasive cancer are predominantly pleomorphic with more than 10 flecks per cm. Architectural distortion and invasive tubular carcinoma are more common than reported in general series.

  10. Vitamin D intake, month the mammogram was taken and mammographic density in Norwegian women aged 50-69.

    Directory of Open Access Journals (Sweden)

    Merete Ellingjord-Dale

    Full Text Available The role of vitamin D in breast cancer etiology is unclear. There is some, but inconsistent, evidence that vitamin D is associated with both breast cancer risk and mammographic density (MD. We evaluated the associations of MD with month the mammogram was taken, and with vitamin D intake, in a population of women from Norway--a country with limited sunlight exposure for a large part of the year.3114 women aged 50-69, who participated in the Norwegian Breast Cancer Screening Program (NBCSP in 2004 or 2006/07, completed risk factor and food frequency (FFQ questionnaires. Dietary and total (dietary plus supplements vitamin D, calcium and energy intakes were estimated by the FFQ. Month when the mammogram was taken was recorded on the mammogram. Percent MD was assessed using a computer assisted method (Madena, University of Southern California after digitization of the films. Linear regression models were used to investigate percent MD associations with month the mammogram was taken, and vitamin D and calcium intakes, adjusting for age, body mass index (BMI, study year, estrogen and progestin therapy (EPT, education, parity, calcium intakes and energy intakes.There was no statistical significant association between the month the mammogram was taken and percent MD. Overall, there was no association between percent MD and quartiles of total or dietary vitamin D intakes, or of calcium intake. However, analysis restricted to women aged <55 years revealed a suggestive inverse association between total vitamin D intake and percent MD (p for trend = 0.03.Overall, we found no strong evidence that month the mammogram was taken was associated with percent MD. We found no inverse association between vitamin D intake and percent MD overall, but observed a suggestive inverse association between dietary vitamin D and MD for women less than 55 years old.

  11. Mammographic features of screening detected pT1 (a–b) invasive breast cancer using BI-RADS lexicon

    International Nuclear Information System (INIS)

    Bargalló, Xavier; Santamaría, Gorane; Velasco, Martín; Amo, Montse del; Arguis, Pedro; Burrel, Marta; Capurro, Sebastian

    2012-01-01

    Aim: To describe mammographic features in screening detected invasive breast cancer less than or equal to 10 mm using Breast Imaging Reporting and Data System lexicon in full-field digital mammography. Patients and methods: A retrospective analysis of 123 pT1 (a–b) invasive breast cancers in women aged 50–69 years from our screening program. Radiologic patterns were: masses, calcifications, distortions, asymmetries and mixed. Masses: shape, margins and density, and calcifications: morphology, number of flecks and size of the cluster were taken into account, following Breast Imaging Reporting and Data System terminology. Results: We found 61 masses (49.6%), 8 masses with calcifications (6.5%), 30 groups of calcifications (24.4%), 19 architectural distortions (15.4%), 1 architectural distortion with calcifications (0.8%), 4 asymmetries (3.2%). Sixty out of 69 masses were irregular in shape, 6 lobular, 2 ovals and 1 round. Thirty-four showed ill-defined margins, 29 spiculated and 6 microlobulated. Most of them showed a density similar to surrounding fibroglandular tissue. Calcifications were pleomorphic or fine linear in 24 of 30 (80%). Most of cases showed more than 10 flecks and a size greater than 1 cm. Conclusion: The predominant radiologic finding is an irregular, isodense mass those margins tend to share different descriptors, being ill-defined margins the most constant finding. Calcifications representing invasive cancer are predominantly pleomorphic with more than 10 flecks per cm. Architectural distortion and invasive tubular carcinoma are more common than reported in general series

  12. Adjustment of Measurements with Multiplicative Errors: Error Analysis, Estimates of the Variance of Unit Weight, and Effect on Volume Estimation from LiDAR-Type Digital Elevation Models

    Directory of Open Access Journals (Sweden)

    Yun Shi

    2014-01-01

    Full Text Available Modern observation technology has verified that measurement errors can be proportional to the true values of measurements such as GPS, VLBI baselines and LiDAR. Observational models of this type are called multiplicative error models. This paper is to extend the work of Xu and Shimada published in 2000 on multiplicative error models to analytical error analysis of quantities of practical interest and estimates of the variance of unit weight. We analytically derive the variance-covariance matrices of the three least squares (LS adjustments, the adjusted measurements and the corrections of measurements in multiplicative error models. For quality evaluation, we construct five estimators for the variance of unit weight in association of the three LS adjustment methods. Although LiDAR measurements are contaminated with multiplicative random errors, LiDAR-based digital elevation models (DEM have been constructed as if they were of additive random errors. We will simulate a model landslide, which is assumed to be surveyed with LiDAR, and investigate the effect of LiDAR-type multiplicative error measurements on DEM construction and its effect on the estimate of landslide mass volume from the constructed DEM.

  13. Anthropometric parameters: weight height, body mass index and mammary volume in relationship with the mammographic pattern

    International Nuclear Information System (INIS)

    Perez-Candela, V.; Busto, C.; Avila, R.; Marrero, M. G.; Liminana, J. M.; Orengo, J. C.

    2001-01-01

    A prospective study to attempt to relate the anthropometric parameters of height, weight, body mass index as well as age with the mammographic patterns obtained for the patients and obtain an anthropometric profile was carried out. The study was performed in 1.000 women who underwent a mammography in cranial-caudal and medial lateral oblique projection of both breasts, independently of whether they were screened or diagnosed. Prior to the performance of the mammography, weight and height were obtained, and this was also performed by the same technicians, and the patient were asked their bra size to deduce breast volume. With the weight, the body mass index of Quetelet was calculated (weight [kg]/height''2 (ml). After reading the mammography, the patient was assigned to one of the four mammographic patterns considered in the BIRADS (Breast Imaging Reporting and Data System) established by the ACR (American College of Radiology): type I (fat). type II (disperse fibroglandular densities), type III (fibroglandular densities distributed heterogeneously), type 4 (dense). The results were introduced into a computer database and the SPSS 8.0 statistical program was applied, using the statistical model of multivariant logistic regression. In women under 40 years, with normal weight, the dense breast pattern accounted for 67.8% and as the body mass index (BMI) increased, this pattern decreased to 25.1%. The fat pattern is 20% and as the BMI increases, this increased to 80%. In 40-60 year old women with normal weight, the dense pattern accounts for 44% and decreases to 20.9% in the grades II, III and IV obese. The fat pattern is 11.1% and increases to 53.7% in the grade II, III and IV obese. In women over 60 with normal, the dense pattern accounts for 19.3% and and decreases to 13% in the grade III obese. The fat pattern is 5.3% and increases to 20.2% in the grade iii of obesity. As age increases, the probability of presenting a mammographic pattern with a fat image in the

  14. Sclerosing adenosis: mammographic and ultrasonographic findings with clinical and histopathological correlation

    International Nuclear Information System (INIS)

    Guenhan-Bilgen, Isil; Memis, Aysenur; Uestuen, Esin Emin; Oezdemir, Necmettin; Erhan, Yildiz

    2002-01-01

    Objective: To evaluate the mammographic and ultrasonographic findings of sclerosing adenosis, a relatively uncommon entity which may sometimes mimic carcinoma. Materials and methods: A retrospective review of the records of 33700 women, who have undergone mammographic examination at our institution between January 1985 and July 2001 revealed 43 histopathologically proven sclerosing adenosis. The history, physical examination, mammographic and ultrasonographic findings were analyzed in all patients. In 30 patients, the nonpalpable lesions were preoperatively localized by the needle-hookwire system under the guidance of mammography (n=22) or ultrasonography (US) (n=8). Radiological features were correlated with histopathological findings. Results: The age of the patients varied between 32 and 55 years (mean, 43.7 years). Only two patients had a family history of breast cancer. In six patients, the presenting complaint was mastalgia. A palpable mass was present in 13 cases. The mammographic findings were; microcalcifications in 24 (55.8%) (clustered in 22, diffuse in two), mass in five (11.6%), asymmetric focal density in three (6.9%), and focal architectural distortion in three (6.9%) patients. Four of the masses were irregularly contoured, while one was well-circumscribed. On US, focal acoustic shadowing without a mass configuration was noted in the three patients who showed asymmetrical focal density on mammography. In eight patients, who showed normal mammograms, a solid mass was detected on US. Two masses had discrete well-circumscribed oval or lobulated contours, while six showed microlobulation and irregularity. In one case, the irregularly contoured mass had marked posterior acoustic shadowing. Two of the three patients, who had focal architectural distortion on mammograms, had an irregularly contoured solid mass, while the third presented as focal acoustic shadowing without a mass configuration. Conclusion: Sclerosing adenosis mostly presents as a nonpalpable

  15. Forensic examination of ink by high-performance thin layer chromatography--the United States Secret Service Digital Ink Library.

    Science.gov (United States)

    Neumann, Cedric; Ramotowski, Robert; Genessay, Thibault

    2011-05-13

    Forensic examinations of ink have been performed since the beginning of the 20th century. Since the 1960s, the International Ink Library, maintained by the United States Secret Service, has supported those analyses. Until 2009, the search and identification of inks were essentially performed manually. This paper describes the results of a project designed to improve ink samples' analytical and search processes. The project focused on the development of improved standardization procedures to ensure the best possible reproducibility between analyses run on different HPTLC plates. The successful implementation of this new calibration method enabled the development of mathematical algorithms and of a software package to complement the existing ink library. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Digital Citizen Participation within Schools in the United Kingdom and Indonesia: An Actor–Network Theory (ANT Perspective

    Directory of Open Access Journals (Sweden)

    Muhammad Yusuf

    2016-11-01

    Full Text Available Citizen engagement and participation are a key focus for government and government agencies, and with the advent of Internet technologies questions arise about the role and impact of technology on citizen participation. This paper aims to explore the role of technology in citizen participation within schools. This research used in-depth comparative case studies using examples from two different schools and school systems, one in the United Kingdom and one in Indonesia. The wider school systems are complex and dynamic environments with multiple stakeholders, media, and supporting systems, and the schools operate under geopolitical and social influences. This paper provides a framework, based on Actor-Network Theory (ANT, for capturing e-participation in schools, particularly identifying the influence of technology as a conduit for enabling, engaging, and empowering stakeholders.

  17. B2B marketing communications in emerging markets : content marketing in digital channels: a case study of the United Arab Emirates

    OpenAIRE

    Banjo, Olugbenga

    2013-01-01

    With the ever increasing online community and opportunities, digital marketing is fast becoming the mainstream in the field of marketing. At the same time marketers have to be up-to-date with the current digital trends in order to be able to improve themselves and make valuable contributions to their organisations. The significance of digital marketing thus should make any thoughtful organisation want to plan for, perform, evaluate and improve its digital marketing endeavours where necessary,...

  18. The implementation of an AR (augmented reality) approach to support mammographic interpretation training: an initial feasibility study

    Science.gov (United States)

    Tang, Qiang; Chen, Yan; Gale, Alastair G.

    2017-03-01

    Appropriate feedback plays an important role in optimising mammographic interpretation training whilst also ensuring good interpretation performance. The traditional keyboard, mouse and workstation technical approach has a critical limitation in providing supplementary image-related information and providing complex feedback in real time. Augmented Reality (AR) provides a possible superior approach in this situation, as feedback can be provided directly overlaying the displayed mammographic images so making a generic approach which can also be vendor neutral. In this study, radiological feedback was dynamically remapped virtually into the real world, using perspective transformation, in order to provide a richer user experience in mammographic interpretation training. This is an initial attempt of an AR approach to dynamically superimpose pre-defined feedback information of a DICOM image on top of a radiologist's view, whilst the radiologist is examining images on a clinical workstation. The study demonstrates the feasibility of the approach, although there are limitations on interactive operations which are due to the hardware used. The results of this fully functional approach provide appropriate feedback/image correspondence in a simulated mammographic interpretation environment. Thus, it is argued that employing AR is a feasible way to provide rich feedback in the delivery of mammographic interpretation training.

  19. EnviroAtlas - Reptile Biodiversity Ecosystem Services Metrics by 12-digit HUC for the Conterminous United States

    Science.gov (United States)

    This EnviroAtlas dataset contains biodiversity metrics reflecting ecosystem services or other aspects of biodiversity for reptile species, based on the number of reptile species as measured by predicted habitat present within a pixel. These metrics were created from grouping national level single species habitat models created by the USGS Gap Analysis Program into smaller ecologically based, phylogeny based, or stakeholder suggested composites. The dataset includes reptile species richness metrics for all reptile species, lizards, snakes, turtles, poisonous reptiles, Natureserve-listed G1,G2, and G3 reptile species, and reptile species listed by IUCN (International Union for Conservation of Nature), PARC (Partners in Amphibian and Reptile Conservation) and SWPARC (Southwest Partners in Amphibian and Reptile Conservation). This dataset was produced by a joint effort of New Mexico State University, US EPA, and USGS to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa

  20. Wavelet processing techniques for digital mammography

    Science.gov (United States)

    Laine, Andrew F.; Song, Shuwu

    1992-09-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis through multiresolution representations. We show that efficient (nonredundant) representations may be identified from digital mammography and used to enhance specific mammographic features within a continuum of scale space. The multiresolution decomposition of wavelet transforms provides a natural hierarchy in which to embed an interactive paradigm for accomplishing scale space feature analysis. Similar to traditional coarse to fine matching strategies, the radiologist may first choose to look for coarse features (e.g., dominant mass) within low frequency levels of a wavelet transform and later examine finer features (e.g., microcalcifications) at higher frequency levels. In addition, features may be extracted by applying geometric constraints within each level of the transform. Choosing wavelets (or analyzing functions) that are simultaneously localized in both space and frequency, results in a powerful methodology for image analysis. Multiresolution and orientation selectivity, known biological mechanisms in primate vision, are ingrained in wavelet representations and inspire the techniques presented in this paper. Our approach includes local analysis of complete multiscale representations. Mammograms are reconstructed from wavelet representations, enhanced by linear, exponential and constant weight functions through scale space. By improving the visualization of breast pathology we can improve the chances of early detection of breast cancers (improve quality) while requiring less time to evaluate mammograms for most patients (lower costs).

  1. Development of a sampling strategy and sample size calculation to estimate the distribution of mammographic breast density in Korean women.

    Science.gov (United States)

    Jun, Jae Kwan; Kim, Mi Jin; Choi, Kui Son; Suh, Mina; Jung, Kyu-Won

    2012-01-01

    Mammographic breast density is a known risk factor for breast cancer. To conduct a survey to estimate the distribution of mammographic breast density in Korean women, appropriate sampling strategies for representative and efficient sampling design were evaluated through simulation. Using the target population from the National Cancer Screening Programme (NCSP) for breast cancer in 2009, we verified the distribution estimate by repeating the simulation 1,000 times using stratified random sampling to investigate the distribution of breast density of 1,340,362 women. According to the simulation results, using a sampling design stratifying the nation into three groups (metropolitan, urban, and rural), with a total sample size of 4,000, we estimated the distribution of breast density in Korean women at a level of 0.01% tolerance. Based on the results of our study, a nationwide survey for estimating the distribution of mammographic breast density among Korean women can be conducted efficiently.

  2. Deep convolutional neural network for mammographic density segmentation

    Science.gov (United States)

    Wei, Jun; Li, Songfeng; Chan, Heang-Ping; Helvie, Mark A.; Roubidoux, Marilyn A.; Lu, Yao; Zhou, Chuan; Hadjiiski, Lubomir; Samala, Ravi K.

    2018-02-01

    Breast density is one of the most significant factors for cancer risk. In this study, we proposed a supervised deep learning approach for automated estimation of percentage density (PD) on digital mammography (DM). The deep convolutional neural network (DCNN) was trained to estimate a probability map of breast density (PMD). PD was calculated as the ratio of the dense area to the breast area based on the probability of each pixel belonging to dense region or fatty region at a decision threshold of 0.5. The DCNN estimate was compared to a feature-based statistical learning approach, in which gray level, texture and morphological features were extracted from each ROI and the least absolute shrinkage and selection operator (LASSO) was used to select and combine the useful features to generate the PMD. The reference PD of each image was provided by two experienced MQSA radiologists. With IRB approval, we retrospectively collected 347 DMs from patient files at our institution. The 10-fold cross-validation results showed a strong correlation r=0.96 between the DCNN estimation and interactive segmentation by radiologists while that of the feature-based statistical learning approach vs radiologists' segmentation had a correlation r=0.78. The difference between the segmentation by DCNN and by radiologists was significantly smaller than that between the feature-based learning approach and radiologists (p approach has the potential to replace radiologists' interactive thresholding in PD estimation on DMs.

  3. Comparison of synthetic mammography, reconstructed from digital breast tomosynthesis, and digital mammography: evaluation of lesion conspicuity and BI-RADS assessment categories.

    Science.gov (United States)

    Mariscotti, Giovanna; Durando, Manuela; Houssami, Nehmat; Fasciano, Mirella; Tagliafico, Alberto; Bosco, Davide; Casella, Cristina; Bogetti, Camilla; Bergamasco, Laura; Fonio, Paolo; Gandini, Giovanni

    2017-12-01

    To compare the interpretive performance of synthetic mammography (SM), reconstructed from digital breast tomosynthesis (DBT), and full-field digital mammography (FFDM) in a diagnostic setting, covering different conditions of breast density and mammographic signs. A retrospective analysis was conducted on 231 patients, who underwent FFDM and DBT (from which SM images were reconstructed) between September 2014-September 2015. The study included 250 suspicious breast lesions, all biopsy proven: 148 (59.2%) malignant and 13 (5.2%) high-risk lesions were confirmed by surgery, 89 (35.6%) benign lesions had radiological follow-up. Two breast radiologists, blinded to histology, independently reviewed all cases. Readings were performed with SM alone, then with FFDM, collecting data on: probability of malignancy for each finding, lesion conspicuity, mammographic features and dimensions of detected lesions. Agreement between readers was good for BI-RADS classification (Cohen's k-coefficient = 0.93 ± 0.02) and for lesion dimension (Wilcoxon's p = 0.76). Visibility scores assigned to SM and FFDM for each lesion were similar for non-dense and dense breasts, however, there were significant differences (p = 0.0009) in distribution of mammographic features subgroups. SM and FFDM had similar sensitivities in non-dense (respectively 94 vs. 91%) and dense breasts (88 vs. 80%) and for all mammographic signs (93 vs. 87% for asymmetric densities, 96 vs. 75% for distortion, 92 vs. 85% for microcalcifications, and both 94% for masses). Based on all data, there was a significant difference in sensitivity for SM (92%) vs. FFDM (87%), p = 0.02, whereas the two modalities yielded similar results for specificity (SM: 60%, FFDM: 62%, p = 0.21). SM alone showed similar interpretive performance to FFDM, confirming its potential role as an alternative to FFDM in women having tomosynthesis, with the added advantage of halving the patient's dose exposure.

  4. Association of Catechol-O-methyltransferase polymorphism Val158Met and mammographic density: A meta-analysis.

    Science.gov (United States)

    Kallionpää, Roope A; Uusitalo, Elina; Peltonen, Juha

    2017-08-15

    The Val158Met polymorphism in catechol-O-methyltransferase (COMT) enzyme reduces the methylation of catechol estrogens, which may affect mammographic density. High mammographic density is a known risk factor of breast cancer. Our aim was to perform meta-analysis of the effect of COMT Val158Met polymorphism on mammographic density. Original studies reporting data on mammographic density, stratified by the presence of COMT Val158Met polymorphism, were identified and combined using genetic models Met/Val vs. Val/Val, Met/Met vs. Val/Val, Val/Met+Met/Met vs. Val/Val (dominant model) and Met/Met vs. Val/Met+Val/Val (recessive model). Subgroup analyses by breast cancer status, menopausal status and use of hormone replacement therapy (HRT) were also performed. Eight studies were included in the meta-analysis. The overall effect in percent mammographic density was -1.41 (CI -2.86 to 0.05; P=0.06) in the recessive model. Exclusion of breast cancer patients increased the effect size to -1.93 (CI -3.49 to -0.37; P=0.02). The results suggested opposite effect of COMT Val158Met for postmenopausal users of HRT versus premenopausal women or postmenopausal non-users of HRT. COMT Val158Met polymorphism may be associated with mammographic density at least in healthy women. Menopausal status and HRT should be taken into account in future studies to avoid masking of the underlying effects. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Impact of contra-lateral breast reshaping on mammographic surveillance in women undergoing breast reconstruction following mastectomy for breast cancer.

    Science.gov (United States)

    Nava, Maurizio B; Rocco, Nicola; Catanuto, Giuseppe; Falco, Giuseppe; Capalbo, Emanuela; Marano, Luigi; Bordoni, Daniele; Spano, Andrea; Scaperrotta, Gianfranco

    2015-08-01

    The ultimate goal of breast reconstruction is to achieve symmetry with the contra-lateral breast. Contra-lateral procedures with wide parenchymal rearrangements are suspected to impair mammographic surveillance. This study aims to evaluate the impact on mammographic detection of mastopexies and breast reductions for contralateral adjustment in breast reconstruction. We retrospectively evaluated 105 women affected by uni-lateral breast cancer who underwent mastectomy and immediate two-stage reconstruction between 2002 and 2007. We considered three groups according to the contra-lateral reshaping technique: mastopexy or breast reduction with inferior dermoglandular flap (group 1); mastopexy or breast reduction without inferior dermoglandular flap (group 2); no contra-lateral reshaping (group 3). We assessed qualitative mammographic variations and breast density in the three groups. Statistically significant differences have been found when comparing reshaped groups with non reshaped groups regarding parenchymal distortions, skin thickening and stromal edema, but these differences did not affect cancer surveillance. The surveillance mammography diagnostic accuracy in contra-lateral cancer detection was not significantly different between the three groups (p = 0.56), such as the need for MRI for equivocal findings at mammographic contra-lateral breast (p = 0.77) and the need for core-biopsies to confirm mammographic suspect of contra-lateral breast cancer (p = 0.90). This study confirms previous reports regarding the safety of mastopexies and breast reductions when performed in the setting of contra-lateral breast reshaping after breast reconstruction. Mammographic accuracy, sensitivity and specificity are not affected by the glandular re-arrangement. These results provide a further validation of the safety of current reconstructive paradigms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Landscape unit based digital elevation model development for the freshwater wetlands within the Arthur C. Marshall Loxahatchee National Wildlife Refuge, Southeastern Florida

    Science.gov (United States)

    Xie, Zhixiao; Liu, Zhongwei; Jones, John W.; Higer, Aaron L.; Telis, Pamela A.

    2011-01-01

    The hydrologic regime is a critical limiting factor in the delicate ecosystem of the greater Everglades freshwater wetlands in south Florida that has been severely altered by management activities in the past several decades. "Getting the water right" is regarded as the key to successful restoration of this unique wetland ecosystem. An essential component to represent and model its hydrologic regime, specifically water depth, is an accurate ground Digital Elevation Model (DEM). The Everglades Depth Estimation Network (EDEN) supplies important hydrologic data, and its products (including a ground DEM) have been well received by scientists and resource managers involved in Everglades restoration. This study improves the EDEN DEMs of the Loxahatchee National Wildlife Refuge, also known as Water Conservation Area 1 (WCA1), by adopting a landscape unit (LU) based interpolation approach. The study first filtered the input elevation data based on newly available vegetation data, and then created a separate geostatistical model (universal kriging) for each LU. The resultant DEMs have encouraging cross-validation and validation results, especially since the validation is based on an independent elevation dataset (derived by subtracting water depth measurements from EDEN water surface elevations). The DEM product of this study will directly benefit hydrologic and ecological studies as well as restoration efforts. The study will also be valuable for a broad range of wetland studies.

  7. Clinical evaluation of digital displays for PACS work stations

    International Nuclear Information System (INIS)

    Highman, J.H.; Craig, J.O.M.C.; Dawood, R.M.; Todd-Pokropek, A.; Porter, A.; Glass, H.I.; Wadsworth, J.

    1989-01-01

    The requirements for display of radiographic images at PAVS work stations is critical if reporting at CRT terminal is to become routine practice. This study determines the accuracy of reporting for the digital images displayed on commercially available systems. A number of pathologic conditions were selected by virtue of the high demands they made on spatial and contrast resolution. They included hyperparathyroid subperiosteal resorption in the hands, pneumocystis pneumonia, and mammographic microcalcification. For each condition, a series of up to 100 films were collected; approximately half were normal controls. These were digitized at 200 μm. Original films and their digitized images displayed on a 1,280-line monitor have been reported

  8. Mammographic density and breast cancer risk by family history in women of white and Asian ancestry.

    Science.gov (United States)

    Maskarinec, Gertraud; Nakamura, Kaylae L; Woolcott, Christy G; Conroy, Shannon M; Byrne, Celia; Nagata, Chisato; Ursin, Giske; Vachon, Celine M

    2015-04-01

    Mammographic density, i.e., the radiographic appearance of the breast, is a strong predictor of breast cancer risk. To determine whether the association of breast density with breast cancer is modified by a first-degree family history of breast cancer (FHBC) in women of white and Asian ancestry, we analyzed data from four case-control studies conducted in the USA and Japan. The study population included 1,699 breast cancer cases and 2,422 controls, of whom 45% reported white (N = 1,849) and 40% Asian (N = 1,633) ancestry. To standardize mammographic density assessment, a single observer re-read all mammograms using one type of interactive thresholding software. Logistic regression was applied to estimate odds ratios (OR) while adjusting for confounders. Overall, 496 (12%) of participants reported a FHBC, which was significantly associated with breast cancer risk in the adjusted model (OR 1.51; 95% CI 1.23-1.84). There was a statistically significant interaction on a multiplicative scale between FHBC and continuous percent density (per 10 % density: p = 0.03). The OR per 10% increase in percent density was higher among women with a FHBC (OR 1.30; 95% CI 1.13-1.49) than among those without a FHBC (OR 1.14; 1.09-1.20). This pattern was apparent in whites and Asians. The respective ORs were 1.45 (95% CI 1.17-1.80) versus 1.22 (95% CI 1.14-1.32) in whites, whereas the values in Asians were only 1.24 (95% CI 0.97-1.58) versus 1.09 (95% CI 1.00-1.19). These findings support the hypothesis that women with a FHBC appear to have a higher risk of breast cancer associated with percent mammographic density than women without a FHBC.

  9. Ultrasound guided core biopsy of suspicious mammographic calcifications using high frequency and power Doppler ultrasound

    International Nuclear Information System (INIS)

    Teh, W.L.; Wilson, A.R.M; Evans, A.J.; Burrell, H.; Pinder, S.E.; Ellis, I.O.

    2000-01-01

    AIM: The pre-operative diagnosis of suspicious mammographic microcalcifications usually requires stereotactic needle biopsy. The aim of this study was to evaluate if high frequency 13 MHz ultrasound (HFUS) and power Doppler (PD) can aid visualization and biopsy of microcalcifications. MATERIALS AND METHODS: Forty-four consecutive patients presenting with microcalcifications without associated mammographic or palpable masses were examined with HFUS and PD. Ultrasound-guided core biopsy (USCB) was performed where possible. Stereotactic biopsy was carried out when US-guided biopsy was unsuccessful. Surgery was performed if a diagnosis of malignancy was made on core biopsy or if the repeat core biopsy was non-diagnostic. RESULTS: Forty-one patients (93%) had ultrasound abnormalities corresponding to mammographic calcification. USCB was performed on 37 patients. In 29/37, USCB obtained a definitive result (78.4%). USCB was non-diagnostic in 4/9 benign (44.4%) and 4/28 (14.3%) malignant lesions biopsied. The complete and absolute sensitivities for malignancy using USCB were 85.7% (24/28) and 81% (23/28), respectively. USCB correctly identified invasive disease in 12/23 (52.2%) cases. There was no significant difference in the presence of abnormal flow on PD between benign and malignant lesions. However, abnormal PD vascularity was present in 43.5% of invasive cancer and was useful in directing successful biopsy in eight cases. CONCLUSION: The combination of high frequency US with PD is useful in the detection and guidance of successful needle biopsy of microcalcifications particularly where there is an invasive focus within larger areas of DCIS. Teh, W.L. (2000)

  10. Smoking and high-risk mammographic parenchymal patterns: a case-control study

    International Nuclear Information System (INIS)

    Sala, Evis; Warren, Ruth; McCann, Jenny; Duffy, Stephen; Luben, Robert; Day, Nicholas

    2000-01-01

    Current smoking was strongly and inversely associated with high-risk patterns, after adjustment for concomitant risk factors. Relative to never smokers, current smokers were significantly less likely to have a high-risk pattern. Similar results were obtained when the analysis was confined to postmenopausal women. Past smoking was not related to the mammographic parenchymal patterns. The overall effect in postmenopausal women lost its significance when adjusted for other risk factors for P2/DY patterns that were found to be significant in the present study, although the results are still strongly suggestive. The present data indicate that adjustment for current smoking status is important when evaluating the relationship between mammographic parenchymal pattern and breast cancer risk. They also indicate that smoking is a prominent potential confounder when analyzing effects of other risk factors such as obesity-related variables. It appears that parenchymal patterns may act as an informative biomarker of the effect of cigarette smoking on breast cancer risk. Overall, epidemiological studies [1,2,3,4] have reported no substantial association between cigarette smoking and the risk of breast cancer. Some studies [5,6,7] reported a significant increase of breast cancer risk among smokers. In recent studies that addressed the association between breast cancer and cigarette smoking, however, there was some suggestion of a decreased risk [8,9,10], especially among current smokers, ranging from approximately 10 to 30% [9,10]. Brunet et al [11] reported that smoking might reduce the risk of breast cancer by 44% in carriers of BRCA1 or BRCA2 gene mutations. Wolfe [12] described four different mammographic patterns created by variations in the relative amounts of fat, epithelial and connective tissue in the breast, designated N1, P1, P2 and DY. Women with either P2 or DY pattern are considered at greater risk for breast cancer than those with N1 or P1 pattern [12

  11. Varying performance in mammographic interpretation across two countries: Do results indicate reader or population variances?

    Science.gov (United States)

    Soh, BaoLin P.; Lee, Warwick B.; Wong, Jill; Sim, Llewellyn; Hillis, Stephen L.; Tapia, Kriscia A.; Brennan, Patrick C.

    2016-03-01

    Aim: To compare the performance of Australian and Singapore breast readers interpreting a single test-set that consisted of mammographic examinations collected from the Australian population. Background: In the teleradiology era, breast readers are interpreting mammographic examinations from different populations. The question arises whether two groups of readers with similar training backgrounds, demonstrate the same level of performance when presented with a population familiar only to one of the groups. Methods: Fifty-three Australian and 15 Singaporean breast radiologists participated in this study. All radiologists were trained in mammogram interpretation and had a median of 9 and 15 years of experience in reading mammograms respectively. Each reader interpreted the same BREAST test-set consisting of sixty de-identified mammographic examinations arising from an Australian population. Performance parameters including JAFROC, ROC, case sensitivity as well as specificity were compared between Australian and Singaporean readers using a Mann Whitney U test. Results: A significant difference (P=0.036) was demonstrated between the JAFROC scores of the Australian and Singaporean breast radiologists. No other significant differences were observed. Conclusion: JAFROC scores for Australian radiologists were higher than those obtained by the Singaporean counterparts. Whilst it is tempting to suggest this is down to reader expertise, this may be a simplistic explanation considering the very similar training and audit backgrounds of the two populations of radiologists. The influence of reading images that are different from those that radiologists normally encounter cannot be ruled out and requires further investigation, particularly in the light of increasing international outsourcing of radiologic reporting.

  12. 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.

  13. Risk stratification of women with false-positive test results in mammography screening based on mammographic morphology and density

    DEFF Research Database (Denmark)

    Winkel, Rikke Rass; von Euler-Chelpin, My Catarina; Lynge, Elsebeth

    2017-01-01

    a case-control study nested in the population-based screening programme in Copenhagen, Denmark. We included 288 cases and 288 controls based on a cohort of 4743 women with at least one FP-test result in 1991–2005 who were followed up until 17 April 2008. Film-based mammograms were assessed using...... the Breast Imaging-Reporting and Data System (BI-RADS) density classification, the Tabár classification, and two automated techniques quantifying percentage mammographic density (PMD) and mammographic texture (MTR), respectively. The association with breast cancer was estimated using binary logistic...

  14. Local breast density assessment using reacquired mammographic images.

    Science.gov (United States)

    García, Eloy; Diaz, Oliver; Martí, Robert; Diez, Yago; Gubern-Mérida, Albert; Sentís, Melcior; Martí, Joan; Oliver, Arnau

    2017-08-01

    The aim of this paper is to evaluate the spatial glandular volumetric tissue distribution as well as the density measures provided by Volpara™ using a dataset composed of repeated pairs of mammograms, where each pair was acquired in a short time frame and in a slightly changed position of the breast. We conducted a retrospective analysis of 99 pairs of repeatedly acquired full-field digital mammograms from 99 different patients. The commercial software Volpara™ Density Maps (Volpara Solutions, Wellington, New Zealand) is used to estimate both the global and the local glandular tissue distribution in each image. The global measures provided by Volpara™, such as breast volume, volume of glandular tissue, and volumetric breast density are compared between the two acquisitions. The evaluation of the local glandular information is performed using histogram similarity metrics, such as intersection and correlation, and local measures, such as statistics from the difference image and local gradient correlation measures. Global measures showed a high correlation (breast volume R=0.99, volume of glandular tissue R=0.94, and volumetric breast density R=0.96) regardless the anode/filter material. Similarly, histogram intersection and correlation metric showed that, for each pair, the images share a high degree of information. Regarding the local distribution of glandular tissue, small changes in the angle of view do not yield significant differences in the glandular pattern, whilst changes in the breast thickness between both acquisition affect the spatial parenchymal distribution. This study indicates that Volpara™ Density Maps is reliable in estimating the local glandular tissue distribution and can be used for its assessment and follow-up. Volpara™ Density Maps is robust to small variations of the acquisition angle and to the beam energy, although divergences arise due to different breast compression conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Comparison of Mammographic Changes Across Three Different Fractionation Schedules for Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Sibo [Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States); Paster, Lina F. [Department of Radiology, Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States); Kim, Sinae [Biometrics Division, Rutgers Cancer Institute of New Jersey, and Department of Biostatistics, Rutgers School of Public Health, Rutgers, New Jersey (United States); Kirstein, Laurie [Division of Surgical Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States); Haffty, Bruce G.; Ferro, Adam [Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States); Amorosa, Judith [Department of Radiology, Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States); Goyal, Sharad, E-mail: goyalsh@rutgers.edu [Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey and Rutgers Robert Wood Johnson Medical School, Rutgers, New Jersey (United States)

    2016-06-01

    Purpose: As the use of hypofractionated breast radiation therapy (RT) increases, so will the need for long-term data on post-RT mammographic changes. The purpose of the present study was to longitudinally compare the incidence of common mammographic sequelae seen after breast conserving surgery and RT in patients treated with accelerated partial breast irradiation (APBI), hypofractionated whole breast irradiation (HWBI), and conventionally fractionated whole breast irradiation (WBI). Methods and Materials: Patients treated with either APBI or HWBI after breast conserving therapy and with ≥3 mammograms of the treated breast were identified. They were matched 1:1 by age ±5 years to patients treated with WBI. The mammograms were evaluated for common post-RT breast findings by a mammographer who was unaware of the treatment. The outcomes were analyzed using a cumulative logistic regression model; P<.05 indicated statistically significance. Results: Of 89 patients treated with RT from 2006 to 2011, 29 had received APBI, 30 had received HWBI, and 30 had received WBI. Their median age was 60 years (range 33-83). A total of 605 mammograms were evaluated, with a median follow-up of 48 months. The treatment technique did not affect the severity of architectural distortion when the groups were evaluated longitudinally. The likelihood of finding skin thickening decreased with increasing follow-up duration (odds ratio 0.6; P<.001) adjusted for fractionation schemes. No differences were seen with respect to changes in skin thickening, fluid collections, or calcifications among the treatment groups, after adjustment for the follow-up time. The clinical characteristics, including age, race, T stage, and chemotherapy use, were not linked to the likelihood of finding several mammographic phenomena over time. Conclusions: Although specific post-treatment imaging findings evolved over time, RT fractionation did not alter the relative incidence or severity of architectural

  16. Controlled single-blind clinical evaluation of low-dose mammographic screen: film systems

    International Nuclear Information System (INIS)

    Sickles, E.A.; Genant, H.K.

    1979-01-01

    The ability of five low-dose mammographic screen-film systems to portray normal and abnormal breast structures was evaluated in parallel with a study of physical image properties. Single-blind evaluations of the visibility of normal breast architecture, mass lesions, and calcifications were made on the mammograms of 100 patients radiographed with each of the systems. There was increased noise and slightly poorer resolution of the faster recording systems, but there was no difference in final diagnostic impressions among the five systems. These results suggest that the faster systems will result in substantial dose reduction without sacrificing diagnostic accuracy

  17. Combining different views of mammographic texture resemblance (MTR) marker of breast cancer risk

    DEFF Research Database (Denmark)

    Sun, S.; Karemore, Gopal; Chernoff, Konstantin

    the subsequent 4 years whereas 245 cases had a diagnosis 2-4 years post mammography. We employed the MTR supervised texture learning framework to perform risk evaluation from a single mammography view. In the framework 20,000 pixels were sampled and classified by a kNN pixel classifier. A feature selection step......PURPOSE Mammographic density is a well established breast cancer risk factor. Texture analysis in terms of the Mammographoc Texture Resemblance (MTR) marker has recently shown to add to risk segregation. Hitherto only single view MTR analysis has been performed. Standard mammography examinations...

  18. A comparison of five methods of measuring mammographic density: a case-control study.

    Science.gov (United States)

    Astley, Susan M; Harkness, Elaine F; Sergeant, Jamie C; Warwick, Jane; Stavrinos, Paula; Warren, Ruth; Wilson, Mary; Beetles, Ursula; Gadde, Soujanya; Lim, Yit; Jain, Anil; Bundred, Sara; Barr, Nicola; Reece, Valerie; Brentnall, Adam R; Cuzick, Jack; Howell, Tony; Evans, D Gareth

    2018-02-05

    High mammographic density is associated with both risk of cancers being missed at mammography, and increased risk of developing breast cancer. Stratification of breast cancer prevention and screening requires mammographic density measures predictive of cancer. This study compares five mammographic density measures to determine the association with subsequent diagnosis of breast cancer and the presence of breast cancer at screening. Women participating in the "Predicting Risk Of Cancer At Screening" (PROCAS) study, a study of cancer risk, completed questionnaires to provide personal information to enable computation of the Tyrer-Cuzick risk score. Mammographic density was assessed by visual analogue scale (VAS), thresholding (Cumulus) and fully-automated methods (Densitas, Quantra, Volpara) in contralateral breasts of 366 women with unilateral breast cancer (cases) detected at screening on entry to the study (Cumulus 311/366) and in 338 women with cancer detected subsequently. Three controls per case were matched using age, body mass index category, hormone replacement therapy use and menopausal status. Odds ratios (OR) between the highest and lowest quintile, based on the density distribution in controls, for each density measure were estimated by conditional logistic regression, adjusting for classic risk factors. The strongest predictor of screen-detected cancer at study entry was VAS, OR 4.37 (95% CI 2.72-7.03) in the highest vs lowest quintile of percent density after adjustment for classical risk factors. Volpara, Densitas and Cumulus gave ORs for the highest vs lowest quintile of 2.42 (95% CI 1.56-3.78), 2.17 (95% CI 1.41-3.33) and 2.12 (95% CI 1.30-3.45), respectively. Quantra was not significantly associated with breast cancer (OR 1.02, 95% CI 0.67-1.54). Similar results were found for subsequent cancers, with ORs of 4.48 (95% CI 2.79-7.18), 2.87 (95% CI 1.77-4.64) and 2.34 (95% CI 1.50-3.68) in highest vs lowest quintiles of VAS, Volpara and Densitas

  19. Mammographic and sonographic findings of unilateral breast edema in congestive heart failure : a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Kyung; Lee, Seung Koo; Oh, Ki Keun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-06-01

    Unilateral breast edema has many causes, though among these, congestive heart failure is rare. We report mammographic and sonographic findings of unilateral breast edema due to congestive heart failure. Mammography showed diffuse increase density and skin thickening but no evidence of mass or calcification. Ultrasonography showed skin thickening and increased echogenicity in the subcutaneous fat layer, while in the dermal layer, with tubular and reticular anechoic structures suggestive of dilated lymphatics were seen. After treatment of the heart failure, resolution of the abnormalities seen on mammogram established that these were secondary findings.

  20. Mammographic and sonographic findings of unilateral breast edema in congestive heart failure : a case report

    International Nuclear Information System (INIS)

    Kim, Eun Kyung; Lee, Seung Koo; Oh, Ki Keun

    1997-01-01

    Unilateral breast edema has many causes, though among these, congestive heart failure is rare. We report mammographic and sonographic findings of unilateral breast edema due to congestive heart failure. Mammography showed diffuse increase density and skin thickening but no evidence of mass or calcification. Ultrasonography showed skin thickening and increased echogenicity in the subcutaneous fat layer, while in the dermal layer, with tubular and reticular anechoic structures suggestive of dilated lymphatics were seen. After treatment of the heart failure, resolution of the abnormalities seen on mammogram established that these were secondary findings

  1. Volumetric mammographic density: heritability and association with breast cancer susceptibility loci.

    Science.gov (United States)

    Brand, Judith S; Humphreys, Keith; Thompson, Deborah J; Li, Jingmei; Eriksson, Mikael; Hall, Per; Czene, Kamila

    2014-12-01

    Mammographic density is a strong heritable trait, but data on its genetic component are limited to area-based and qualitative measures. We studied the heritability of volumetric mammographic density ascertained by a fully-automated method and the association with breast cancer susceptibility loci. Heritability of volumetric mammographic density was estimated with a variance component model in a sib-pair sample (N pairs = 955) of a Swedish screening based cohort. Associations with 82 established breast cancer loci were assessed in an independent sample of the same cohort (N = 4025 unrelated women) using linear models, adjusting for age, body mass index, and menopausal status. All tests were two-sided, except for heritability analyses where one-sided tests were used. After multivariable adjustment, heritability estimates (standard error) for percent dense volume, absolute dense volume, and absolute nondense volume were 0.63 (0.06) and 0.43 (0.06) and 0.61 (0.06), respectively (all P associated with rs10995190 (ZNF365; P = 9.0 × 10(-6) and 8.9 × 10(-7), respectively) and rs9485372 (TAB2; P = 1.8 × 10(-5) and 1.8 × 10(-3), respectively). We also observed associations of rs9383938 (ESR1) and rs2046210 (ESR1) with the absolute dense volume (P = 2.6 × 10(-4) and 4.6 × 10(-4), respectively), and rs6001930 (MLK1) and rs17356907 (NTN4) with the absolute nondense volume (P = 6.7 × 10(-6) and 8.4 × 10(-5), respectively). Our results support the high heritability of mammographic density, though estimates are weaker for absolute than percent dense volume. We also demonstrate that the shared genetic component with breast cancer is not restricted to dense tissues only. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Mucinous (colloid) breast cancer: mammographic and US features with histologic correlation

    International Nuclear Information System (INIS)

    Memis, Aysenur; Ozdemir, Necmettin; Parildar, Mustafa; Ustun, Esin Emin; Erhan, Yildiz

    2000-01-01

    Objective: Mucinous carcinoma of the breast presents with different survival rates in pure and mixed types. The purpose of this study was to correlate the mammographic and ultrasonographic findings of mucinous carcinoma with histologic features in different types and mucin rates. Material and methods: Thirty-four patients (2.3%) had mucinous cancer after retrospective review of the 1439 breast cancers diagnosed between 1990 and 1996. Twenty-seven patients, 19 pure and eight mixed type of mucinous carcinomas of the breast, were included in this study to evaluate the imaging findings. In 22 of these, the microscopic slides were available and re-evaluated to estimate the volume of extracellular mucin. The volume of the extracellular mucin was classified histologically as: (+), less than 50% of mucin; (++), 50-80% of mucin; and (+++), more than 80% of mucin. Mammographic features with emphasis on margin characteristics and sonographic echo pattern of tumors were correlated with histologic findings. Results: Ten cases (53%) of pure mucinous type carcinomas had a circumscribed mass lesion on the mammograms. The well-defined, lobulated margins of the masses were well correlated with pure histologic type (P 2 analysis) Two-thirds of these tumors had high volume extracellular mucin. All mixed type mucinous carcinomas demonstrated poorly defined or spiculated margins with no relation to the mucin rates (P<0.01). The sonographic appearances of the tumors showed correlation with histologic types. Most of the pure type carcinomas (53%) were seen with isoechogenic echo texture relative to that of subcutaneous fat, while all of the mixed type carcinomas were hypoechogenic (P<0.01). Conclusion: The mammographic and sonographic features of mucinous breast carcinoma show differences in pure and mixed types of the tumor. The most common mammographic appearance of pure mucinous carcinomas with high percentages of mucin is a mass lesion having well-defined margins, which is

  3. Image simulation and a model of noise power spectra across a range of mammographic beam qualities

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, Alistair, E-mail: alistairmackenzie@nhs.net; Dance, David R.; Young, Kenneth C. [National Coordinating Centre for the Physics of Mammography, Royal Surrey County Hospital, Guildford GU2 7XX, United Kingdom and Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Diaz, Oliver [Centre for Vision, Speech and Signal Processing, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom and Computer Vision and Robotics Research Institute, University of Girona, Girona 17071 (Spain)

    2014-12-15

    Purpose: The aim of this work is to create a model to predict the noise power spectra (NPS) for a range of mammographic radiographic factors. The noise model was necessary to degrade images acquired on one system to match the image quality of different systems for a range of beam qualities. Methods: Five detectors and x-ray systems [Hologic Selenia (ASEh), Carestream computed radiography CR900 (CRc), GE Essential (CSI), Carestream NIP (NIPc), and Siemens Inspiration (ASEs)] were characterized for this study. The signal transfer property was measured as the pixel value against absorbed energy per unit area (E) at a reference beam quality of 28 kV, Mo/Mo or 29 kV, W/Rh with 45 mm polymethyl methacrylate (PMMA) at the tube head. The contributions of the three noise sources (electronic, quantum, and structure) to the NPS were calculated by fitting a quadratic at each spatial frequency of the NPS against E. A quantum noise correction factor which was dependent on beam quality was quantified using a set of images acquired over a range of radiographic factors with different thicknesses of PMMA. The noise model was tested for images acquired at 26 kV, Mo/Mo with 20 mm PMMA and 34 kV, Mo/Rh with 70 mm PMMA for three detectors (ASEh, CRc, and CSI) over a range of exposures. The NPS were modeled with and without the noise correction factor and compared with the measured NPS. A previous method for adapting an image to appear as if acquired on a different system was modified to allow the reference beam quality to be different from the beam quality of the image. The method was validated by adapting the ASEh flat field images with two thicknesses of PMMA (20 and 70 mm) to appear with the imaging characteristics of the CSI and CRc systems. Results: The quantum noise correction factor rises with higher beam qualities, except for CR systems at high spatial frequencies, where a flat response was found against mean photon energy. This is due to the dominance of secondary quantum noise

  4. Acceptance testing in digital systems of mammography. Protocols applicability; Pruebas de aceptacion en equipos digitales de mamografia. Aplicabilidad de protocolos

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, R.; Espana, M.L.; Garcia Castanon, P.; Gomez Barrado, A.; Rodriguez Martin, G.; Fernandez Bedoya, B.

    2011-07-01

    Acceptance testing of mammographic imaging systems technical is the first approach in order to guarantee that mammograms will be achieved with the minimum radiation dose compatible with an image quality suitable for diagnose purposes. The aim of this study is to assess the practical applicability of different protocols in acceptance test of digital mammographic systems. This study has been carried out on the results of the acceptance tests of five flat panel digital mammographic systems. Parameters established in the systems technical specifications and those evaluated in the consulted protocols were tested. Due to the fact that the legislation in our country does not demand to consider a specific protocol, the results obtained were also compared considering different existing protocols. Results show discrepancies between manufacturers limiting values and those established in the protocols. Some parameters, such as the automatic exposure control compensation and the detector noise, were found out to meet or not the limiting value, depending on the selected protocol. From our results we could suggest, that protocols from manufacturers should be adapted to acknowledged documents on acceptance testing in digital mammography. They buyer representative could even specify the protocol to be followed during the acceptance tests. (Author). 25 refs.

  5. Hexagonal wavelet processing of digital mammography

    Science.gov (United States)

    Laine, Andrew F.; Schuler, Sergio; Huda, Walter; Honeyman-Buck, Janice C.; Steinbach, Barbara G.

    1993-09-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis through overcomplete multiresolution representations. We show that efficient representations may be identified from digital mammograms and used to enhance features of importance to mammography within a continuum of scale-space. We present a method of contrast enhancement based on an overcomplete, non-separable multiscale representation: the hexagonal wavelet transform. Mammograms are reconstructed from transform coefficients modified at one or more levels by local and global non-linear operators. Multiscale edges identified within distinct levels of transform space provide local support for enhancement. We demonstrate that features extracted from multiresolution representations can provide an adaptive mechanism for accomplishing local contrast enhancement. We suggest that multiscale detection and local enhancement of singularities may be effectively employed for the visualization of breast pathology without excessive noise amplification.

  6. Evaluation of mammographic surveillance services in women aged 40-49 years with a moderate family history of breast cancer: a single-arm cohort study.

    Science.gov (United States)

    Duffy, S W; Mackay, J; Thomas, S; Anderson, E; Chen, T H H; Ellis, I; Evans, G; Fielder, H; Fox, R; Gui, G; Macmillan, D; Moss, S; Rogers, C; Sibbering, M; Wallis, M; Warren, R; Watson, E; Whynes, D; Allgood, P; Caunt, J

    2013-03-01

    Women with a significant family history of breast cancer are often offered more intensive and earlier surveillance than is offered to the general population in the National Breast Screening Programme. Up to now, this strategy has not been fully evaluated. To evaluate the benefit of mammographic surveillance for women aged 40-49 years at moderate risk of breast cancer due to family history. The study is referred to as FH01. This was a single-arm cohort study with recruitment taking place between January 2003 and February 2007. Recruits were women aged women were offered annual mammography for at least 5 years and observed for the occurrence of breast cancer during the surveillance period. The age group 40-44 years was targeted so that they would still be aged women, 94% of whom were aged women aged 40-49 years with a significant family history of breast or ovarian cancer is both clinically effective in reducing breast cancer mortality and cost-effective. There is a need to further standardise familial risk assessment, to research the impact of digital mammography and to clarify the role of breast density in this population. National Research Register N0484114809. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 11. See the HTA programme website for further project information.

  7. Likelihood of early detection of breast cancer in relation to false-positive risk in life-time mammographic screening: population-based cohort study.

    Science.gov (United States)

    Otten, J D M; Fracheboud, J; den Heeten, G J; Otto, S J; Holland, R; de Koning, H J; Broeders, M J M; Verbeek, A L M

    2013-10-01

    Women require balanced, high-quality information when making an informed decision on screening benefits and harms before attending biennial mammographic screening. The cumulative risk of a false-positive recall and/or (small) screen-detected or interval cancer over 13 consecutive screening examinations for women aged 50 from the start of screening were estimated using data from the Nijmegen programme, the Netherlands. Women who underwent 13 successive screens in the period 1975-1976 had a 5.3% cumulative chance of a screen-detected cancer, with a 4.2% risk of at least one false-positive recall. The risk of being diagnosed with interval cancer was 3.7%. Two decades later, these estimates were 6.9%, 7.3% and 2.9%, respectively. The chance of detection of a small, favourable invasive breast cancer, anticipating a normal life-expectancy, rose from 2.3% to 3.7%. Extrapolation to digital screening mammography indicates that the proportion of false-positive results will rise to 16%. Dutch women about to participate in the screening programme can be reassured that the chance of false-positive recall in the Netherlands is relatively low. A new screening policy and improved mammography have increased the detection of an early screening carcinoma and lowering the risk of interval carcinoma.

  8. Computer aided system for segmentation and visualization of microcalcifications in digital mammograms

    International Nuclear Information System (INIS)

    Reljin, B.; Reljin, I.; Milosevic, Z.; Stojic, T.

    2009-01-01

    Two methods for segmentation and visualization of microcalcifications in digital or digitized mammograms are described. First method is based on modern mathematical morphology, while the second one uses the multifractal approach. In the first method, by using an appropriate combination of some morphological operations, high local contrast enhancement, followed by significant suppression of background tissue, irrespective of its radiology density, is obtained. By iterative procedure, this method highly emphasizes only small bright details, possible microcalcifications. In a multifractal approach, from initial mammogram image, a corresponding multifractal 'images' are created, from which a radiologist has a freedom to change the level of segmentation. An appropriate user friendly computer aided visualization (CAV) system with embedded two methods is realized. The interactive approach enables the physician to control the level and the quality of segmentation. Suggested methods were tested through mammograms from MIAS database as a gold standard, and from clinical praxis, using digitized films and digital images from full field digital mammograph. (authors)

  9. Clinicopathogical characteristics and mammographic features of breast cancer showing architectural distortion on a mammogram

    International Nuclear Information System (INIS)

    Kanzaki, Masao; Hirose, Naoko; Suwa, Kaori; Yoshida, Masayuki; Otuki, Yoshiro; Kobayashi, Hiroshi

    2012-01-01

    Seven hundred and twenty-seven cases of breast cancer were diagnosed in this clinic between January 2003 and December 2010. Of those, 97 patients who showed architectural distortion on mammography were examined regarding the clinicopathological characteristics and mammographic features. The overall rate of architectural distortion was 13.3%, which became higher with progression of the clinical stage. The rate of lymph node metastasis was 50.5% histologically, and the most common histological type was scirrhous carcinoma at 36.2%, papillotubular carcinoma at 33%, invasive lobular carcinoma at 12.1%, and ductal carcinoma in situ at 11%. Cases of extensive ductal spread beyond the breast quadrant, accompanied by microcalcifications or showing architectural distortion in two views on mammography, were present at significantly high rates. Cases showing architectural distortion in two views on mammography accounted for 66% of the total, and, when these cases were not associated with any other mammographic findings, the most suspected histology of the lesion was invasive lobular carcinoma or carcinoma in situ. (author)

  10. The power and the pain: Mammographic compression research from the service-users' perspective

    International Nuclear Information System (INIS)

    Robinson, Leslie; Hogg, Peter; Newton-Hughes, Ann

    2013-01-01

    Purpose: to explore the value service-users can add to our understanding of inter-practitioner compression variability in mammography. Imaging of the breast for the screening and detection of breast carcinoma is generally carried out by mammographic examination the technique for which includes compression of the breast. Evolving research calls into question compression practice in terms of practitioner consistency thus raising the possibility that strong compression may not be required. We were interested to know whether this was important to service-users and if such knowledge might influence their behaviour. Methods: and sample: A qualitative study involving 3 focus groups interviews (n = 4, 6 and 5). Participants were first asked to reflect on their own experiences of breast compression within the context of a breast screening examination, then interpret the results of the evolving research detailed above. We then explored whether these participants might behave differently during future mammography in light being appraised of these research findings. Results: A grounded approach was used to analyse the data into themes. The two overarching themes were i) Service-User Empowerment, which illustrates the difficulties participants believe women would encounter in exercising power in the breast screening mammographic examination; and ii) Service User Experience of Mammography, which unearthed unanticipated aspects of the examination, other than compression, that contribute to pain and discomfort and which therefore need investigation. Conclusion: Involving service-users more collaboratively in research can help investigators understand the impact of their work and highlight patient-relevant areas for further investigation

  11. Computer-aided diagnosis of mammographic masses using geometric verification-based image retrieval

    Science.gov (United States)

    Li, Qingliang; Shi, Weili; Yang, Huamin; Zhang, Huimao; Li, Guoxin; Chen, Tao; Mori, Kensaku; Jiang, Zhengang

    2017-03-01

    Computer-Aided Diagnosis of masses in mammograms is an important indicator of breast cancer. The use of retrieval systems in breast examination is increasing gradually. In this respect, the method of exploiting the vocabulary tree framework and the inverted file in the mammographic masse retrieval have been proved high accuracy and excellent scalability. However it just considered the features in each image as a visual word and had ignored the spatial configurations of features. It greatly affect the retrieval performance. To overcome this drawback, we introduce the geometric verification method to retrieval in mammographic masses. First of all, we obtain corresponding match features based on the vocabulary tree framework and the inverted file. After that, we grasps the main point of local similarity characteristic of deformations in the local regions by constructing the circle regions of corresponding pairs. Meanwhile we segment the circle to express the geometric relationship of local matches in the area and generate the spatial encoding strictly. Finally we judge whether the matched features are correct or not, based on verifying the all spatial encoding are whether satisfied the geometric consistency. Experiments show the promising results of our approach.

  12. Mammographic features and misdiagnosed analysis on 92 cases with breast cancer

    International Nuclear Information System (INIS)

    Liu Mingjuan; Zhang Xiaoling; Guo Yan

    2010-01-01

    Objective: To investigate the atypical X-ray features in breast cancer and improve the accuracy of diagnosis. Methods: Mammographic features of 92 cases with pathologically confirmed breast cancer were analyzed retrospectively. Results: High-density mass with speculated margined, clusters of small calcification, stellate-like lesions were found in 51 cases, the rate of correct diagnosis was 96%-100%. Lobulated high-density mass were found in 17 cases, the correct diagnosis rate was about 88.3% cases with skin thickening were all correctly diagnosed. Round mass, focal parenchymal asymmetry and unidentified lesions were found in 20 cases, the diagnosing rate was less than 20%. Conclusion: Round mass, focal parenchymal asymmetry and unidentified lesions were atypical mammographic features of breast cancer. These lesions were misdiagnosed frequently. It is essential to find the indirect signs and associated finding to avoid misdiagnosis. On the other hand, further ultrasound or MRI were helpful to improve the diagnosis by detecting mass in breast, showing cystic lesions and blood supply. (authors)

  13. Identification of a novel percent mammographic density locus at 12q24.

    Science.gov (United States)

    Stevens, Kristen N; Lindstrom, Sara; Scott, Christopher G; Thompson, Deborah; Sellers, Thomas A; Wang, Xianshu; Wang, Alice; Atkinson, Elizabeth; Rider, David N; Eckel-Passow, Jeanette E; Varghese, Jajini S; Audley, Tina; Brown, Judith; Leyland, Jean; Luben, Robert N; Warren, Ruth M L; Loos, Ruth J F; Wareham, Nicholas J; Li, Jingmei; Hall, Per; Liu, Jianjun; Eriksson, Louise; Czene, Kamila; Olson, Janet E; Pankratz, V Shane; Fredericksen, Zachary; Diasio, Robert B; Lee, Adam M; Heit, John A; DeAndrade, Mariza; Goode, Ellen L; Vierkant, Robert A; Cunningham, Julie M; Armasu, Sebastian M; Weinshilboum, Richard; Fridley, Brooke L; Batzler, Anthony; Ingle, James N; Boyd, Norman F; Paterson, Andrew D; Rommens, Johanna; Martin, Lisa J; Hopper, John L; Southey, Melissa C; Stone, Jennifer; Apicella, Carmel; Kraft, Peter; Hankinson, Susan E; Hazra, Aditi; Hunter, David J; Easton, Douglas F; Couch, Fergus J; Tamimi, Rulla M; Vachon, Celine M

    2012-07-15

    Percent mammographic density adjusted for age and body mass index (BMI) is one of the strongest risk factors for breast cancer and has a heritable component that remains largely unidentified. We performed a three-stage genome-wide association study (GWAS) of percent mammographic density to identify novel genetic loci associated with this trait. In stage 1, we combined three GWASs of percent density comprised of 1241 women from studies at the Mayo Clinic and identified the top 48 loci (99 single nucleotide polymorphisms). We attempted replication of these loci in 7018 women from seven additional studies (stage 2). The meta-analysis of stage 1 and 2 data identified a novel locus, rs1265507 on 12q24, associated with percent density, adjusting for age and BMI (P = 4.43 × 10(-8)). We refined the 12q24 locus with 459 additional variants (stage 3) in a combined analysis of all three stages (n = 10 377) and confirmed that rs1265507 has the strongest association in the 12q24 region (P = 1.03 × 10(-8)). Rs1265507 is located between the genes TBX5 and TBX3, which are members of the phylogenetically conserved T-box gene family and encode transcription factors involved in developmental regulation. Understanding the mechanism underlying this association will provide insight into the genetics of breast tissue composition.

  14. Affinity proteomic profiling of plasma for proteins associated to area-based mammographic breast density.

    Science.gov (United States)

    Byström, Sanna; Eklund, Martin; Hong, Mun-Gwan; Fredolini, Claudia; Eriksson, Mikael; Czene, Kamila; Hall, Per; Schwenk, Jochen M; Gabrielson, Marike

    2018-02-14

    Mammographic breast density is one of the strongest risk factors for breast cancer, but molecular understanding of how breast density relates to cancer risk is less complete. Studies of proteins in blood plasma, possibly associated with mammographic density, are well-suited as these allow large-scale analyses and might shed light on the association between breast cancer and breast density. Plasma samples from 1329 women in the Swedish KARMA project, without prior history of breast cancer, were profiled with antibody suspension bead array (SBA) assays. Two sample sets comprising 729 and 600 women were screened by two different SBAs targeting a total number of 357 proteins. Protein targets were selected through searching the literature, for either being related to breast cancer or for being linked to the extracellular matrix. Association between proteins and absolute area-based breast density (AD) was assessed by quantile regression, adjusting for age and body mass index (BMI). Plasma profiling revealed linear association between 20 proteins and AD, concordant in the two sets of samples (p density and processes of tissue homeostasis, DNA repair, cancer development and/or progression in breast cancer. Further validation and follow-up studies of the shortlisted protein candidates in independent cohorts will be needed to infer their role in breast density and its progression in premenopausal and postmenopausal women.

  15. Mammographic breast density in recent and longer-standing ethiopian immigrants to israel.

    Science.gov (United States)

    Sklair-Levy, Miri; Segev, Anat; Sella, Tamar; Calderon-Margalit, Ronit; Zippel, Douglas

    2018-04-23

    High breast density is associated with an increased risk of breast cancer development. Little is known concerning ethnic variations in breast density and its relevant contributing factors. We aimed to study breast density among Ethiopian immigrants to Israel in comparison with Israeli-born women and to determine any effect on breast density of the length of residency in the immigrant population. Mammographic breast density using the BI-RADS system was estimated and compared between 77 women of Ethiopian origin who live in Israel and 177 Israeli-born controls. Logistic regression analysis was performed to estimate the odds ratios (OR) for high density (BI-RADS score ≥ 3) vs low density (BI-RADS score density compared with Israeli-born women. Adjustments for various cofounders did not affect the results. Time since immigration to Israel seemed to modify the relationship, with a stronger association for women who immigrated within 2 years prior to mammography (OR:0.07, 95% CI: 0.03-0.17) as opposed to women with a longer residency stay in Israel (OR:0.23, 95% CI:0.10-0.50). Adjustments of various confounders did not alter these findings. Breast density in Ethiopian immigrants to Israel is significantly lower than that of Israeli-born controls. Our study suggests a positive association between time since immigration and breast density. Future studies are required to define the possible effects of dietary change on mammographic density following immigration. © 2018 Wiley Periodicals, Inc.

  16. Mammographic Screening of Women Attending a Reference Service Center in Southern Brazil.

    Science.gov (United States)

    Romeiro Lopes, Tiara Cristina; Franca Gravena, Angela Andreia; Demitto, Marcela de Oliveira; Brischiliari, Sheila Cristina Rocha; Borghesan, Deise Helena Pelloso; Dell Agnolo, Catia Millene; Carvalho, Maria Dalva de Barros; Pelloso, Sandra Marisa

    2016-01-01

    To investigate the prevalence of and factors associated with performance of annual mammography by women above 40 years of age. This cross-sectional retrospective study was conducted at an oncology reference service in Southern Brazil from October 2013 to October 2014 with 525 women aged 40 years or older. The prevalence of annual mammography was 54.1%; annual mammographic screening was performed for women without private medical insurance, who were under hormone replacement therapy and who had used contraception in the past. An association was found between non-performance of breast clinical and self-examination and non-performance of mammographic screening. Use of mammography for breast cancer screening in the public health care setting proved to be accessible; nevertheless, the proportion of screened women was low, and they exhibited poor adherence to the basic measures of care recommended for breast assessment. Thus, control of breast cancer requires implementing actions targeting the population most vulnerable to non-adherence to screening in addition to continuously monitoring and assessing that population to reduce the prevalence of this disease.

  17. Sea-level rise and archaeological site destruction: An example from the southeastern United States using DINAA (Digital Index of North American Archaeology).

    Science.gov (United States)

    Anderson, David G; Bissett, Thaddeus G; Yerka, Stephen J; Wells, Joshua J; Kansa, Eric C; Kansa, Sarah W; Myers, Kelsey Noack; DeMuth, R Carl; White, Devin A

    2017-01-01

    The impact of changing climate on terrestrial and underwater archaeological sites, historic buildings, and cultural landscapes can be examined through quantitatively-based analyses encompassing large data samples and broad geographic and temporal scales. The Digital Index of North American Archaeology (DINAA) is a multi-institutional collaboration that allows researchers online access to linked heritage data from multiple sources and data sets. The effects of sea-level rise and concomitant human population relocation is examined using a sample from nine states encompassing much of the Gulf and Atlantic coasts of the southeastern United States. A 1 m rise in sea-level will result in the loss of over >13,000 recorded historic and prehistoric archaeological sites, as well as over 1000 locations currently eligible for inclusion on the National Register of Historic Places (NRHP), encompassing archaeological sites, standing structures, and other cultural properties. These numbers increase substantially with each additional 1 m rise in sea level, with >32,000 archaeological sites and >2400 NRHP properties lost should a 5 m rise occur. Many more unrecorded archaeological and historic sites will also be lost as large areas of the landscape are flooded. The displacement of millions of people due to rising seas will cause additional impacts where these populations resettle. Sea level rise will thus result in the loss of much of the record of human habitation of the coastal margin in the Southeast within the next one to two centuries, and the numbers indicate the magnitude of the impact on the archaeological record globally. Construction of large linked data sets is essential to developing procedures for sampling, triage, and mitigation of these impacts.

  18. Measurement of food colour in L*a*b* units from RGB digital image using least squares support vector machine regression

    Directory of Open Access Journals (Sweden)

    Roberto Romaniello

    2015-12-01

    Full Text Available The aim of this work is to evaluate the potential of least squares support vector machine (LS-SVM regression to develop an efficient method to measure the colour of food materials in L*a*b* units by means of a computer vision systems (CVS. A laboratory CVS, based on colour digital camera (CDC, was implemented and three LS-SVM models were trained and validated, one for each output variables (L*, a*, and b* required by this problem, using the RGB signals generated by the CDC as input variables to these models. The colour target-based approach was used to camera characterization and a standard reference target of 242 colour samples was acquired using the CVS and a colorimeter. This data set was split in two sets of equal sizes, for training and validating the LS-SVM models. An effective two-stage grid search process on the parameters space was performed in MATLAB to tune the regularization parameters γ and the kernel parameters σ2 of the three LS-SVM models. A 3-8-3 multilayer feed-forward neural network (MFNN, according to the research conducted by León et al. (2006, was also trained in order to compare its performance with those of LS-SVM models. The LS-SVM models developed in this research have been shown better generalization capability then the MFNN, allowed to obtain high correlations between L*a*b* data acquired using the colorimeter and the corresponding data obtained by transformation of the RGB data acquired by the CVS. In particular, for the validation set, R2 values equal to 0.9989, 0.9987, and 0.9994 for L*, a* and b* parameters were obtained. The root mean square error values were 0.6443, 0.3226, and 0.2702 for L*, a*, and b* respectively, and the average of colour differences ΔEab was 0.8232±0.5033 units. Thus, LS-SVM regression seems to be a useful tool to measurement of food colour using a low cost CVS.

  19. The significance of circumscribed malignant mammographic masses in the surveillance of BRCA 1/2 gene mutation carriers

    International Nuclear Information System (INIS)

    Kaas, R.; Kroger, R.; Besnard, A.P.E.; Koops, W.; Pameijer, F.A.; Prevoo, W.; Loo, C.E.; Muller, S.H.; Hendriks, J.H.C.L.

    2004-01-01

    Breast cancers in gene mutation carriers may escape mammographic detection because of rapid growth and tumor expansion. Therefore, they may mimic benign lesions on the mammogram. Twenty-nine BRCA 1/2 mutation carriers under surveillance developed 31 breast cancers between 1994 and 2001 at a mean age of 44.2 years. Controls were 63 women with 67 breast cancers in the same period at a mean age of 53.8 years, also under surveillance because of a life time risk of at least 15%. In 26% of the carriers vs. 48% of the controls, mammography was the method that first suspected a malignancy. Seven radiologists performed a retrospective review of the original mammograms to establish technical assessment, with special attention for circumscribed lesions and estimated probability of malignancy. In the mutation carriers seven (23%) circumscribed non-calcified mammographic masses were found and three in the controls (4.5%) P=0.01. These masses were proven to be malignant. In both groups around 70% of these fast-growing circumscribed lesions were detected by the patients. The masses were situated in breasts with a good interpretable breast pattern. BRCA 1/2 mutation carriers had a significantly higher percentage of circumscribed non-calcified mammographic masses that proved to be malignant. These mammographic lesions in women at high risk should be described as at least Birads 0 and worked-up with ultrasound and needle biopsy. (orig.)

  20. Mammographic density changes following discontinuation of tamoxifen in premenopausal women with oestrogen receptor-positive breast cancer.

    Science.gov (United States)

    Kim, Won Hwa; Cho, Nariya; Kim, Young-Seon; Yi, Ann

    2018-04-06

    To evaluate the changes in mammographic density after tamoxifen discontinuation in premenopausal women with oestrogen receptor-positive breast cancers and the underlying factors METHODS: A total of 213 consecutive premenopausal women with breast cancer who received tamoxifen treatment after curative surgery and underwent three mammograms (baseline, after tamoxifen treatment, after tamoxifen discontinuation) were included. Changes in mammographic density after tamoxifen discontinuation were assessed qualitatively (decrease, no change, or increase) by two readers and measured quantitatively by semi-automated software. The association between % density change and clinicopathological factors was evaluated using univariate and multivariate regression analyses. After tamoxifen discontinuation, a mammographic density increase was observed in 31.9% (68/213, reader 1) to 22.1% (47/213, reader 2) by qualitative assessment, with a mean density increase of 1.8% by quantitative assessment compared to density before tamoxifen discontinuation. In multivariate analysis, younger age (≤ 39 years) and greater % density decline after tamoxifen treatment (≥ 17.0%) were independent factors associated with density change after tamoxifen discontinuation (p density change with a mean density increase of 1.8%, which was associated with younger age and greater density change after tamoxifen treatment. • Increased mammographic density after tamoxifen discontinuation can occur in premenopausal women. • Mean density increase after tamoxifen discontinuation was 1.8%. • Density increase is associated with age and density decrease after tamoxifen.

  1. Average glandular dose in patients submitted to mammographic examinations

    International Nuclear Information System (INIS)

    Nogueira, M.S.; Silva, T.A. da; Oliveira, M. de; Joana, G.S.; Oliveira, A.L.K.

    2008-01-01

    Doses in mammography should be maintained as low as possible without reducing the high image quality needed to the early detection of the breast cancer. As the breast is composed of tissues with very soft composition and densities, it increases the difficulty to detect small changes in the normal anatomical structures that may be associated with breast cancer. To achieve the standards of resolution and contrast for mammography, the quality and intensity of the X-ray beam, the breast positioning and compression, the film screen system, and the film processing must be in optimal operational conditions. This study intended to evaluate the mean glandular dose of patients undergoing routine exams in one mammography unit. Patient image analyses were done by a radiologist doctor who took into account 10 evaluation criteria for each CC and MLO incidences. For estimating each patient glandular dose the radiographic technique parameters (kV and mAs) and the thickness of the compressed breast were recorded. European image quality criteria were adopted by the radiologist doctor to accept the image for diagnostic purpose. For breast densities of 50% adipose and 50% glandular tissues the incident air-kerma was measured and the glandular dose calculated considering the x-ray output during the exam. In the study of 50 patients the mean glandular dose varied from 0.90 to 3.27 mGy with a mean value of 1.98 mGy for CC incidences. For MLO incidences the mean glandular doses ranged from 0.97 to 3.98 mGy and a mean value of 2.60 mGy. (author)

  2. Interaction of mammographic breast density with menopausal status and postmenopausal hormone use in relation to the risk of aggressive breast cancer subtypes.

    Science.gov (United States)

    Yaghjyan, Lusine; Tamimi, Rulla M; Bertrand, Kimberly A; Scott, Christopher G; Jensen, Matthew R; Pankratz, V Shane; Brandt, Kathy; Visscher, Daniel; Norman, Aaron; Couch, Fergus; Shepherd, John; Fan, Bo; Chen, Yunn-Yi; Ma, Lin; Beck, Andrew H; Cummings, Steven R; Kerlikowske, Karla; Vachon, Celine M

    2017-09-01

    We examined the associations of mammographic breast density with breast cancer risk by tumor aggressiveness and by menopausal status and current postmenopausal hormone therapy. This study included 2596 invasive breast cancer cases and 4059 controls selected from participants of four nested case-control studies within four established cohorts: the Mayo Mammography Health Study, the Nurses' Health Study, Nurses' Health Study II, and San Francisco Mammography Registry. Percent breast density (PD), absolute dense (DA), and non-dense areas (NDA) were assessed from digitized film-screen mammograms using a computer-assisted threshold technique and standardized across studies. We used polytomous logistic regression to quantify the associations of breast density with breast cancer risk by tumor aggressiveness (defined as presence of at least two of the following tumor characteristics: size ≥2 cm, grade 2/3, ER-negative status, or positive nodes), stratified by menopausal status and current hormone therapy. Overall, the positive association of PD and borderline inverse association of NDA with breast cancer risk was stronger in aggressive vs. non-aggressive tumors (≥51 vs. 11-25% OR 2.50, 95% CI 1.94-3.22 vs. OR 2.03, 95% CI 1.70-2.43, p-heterogeneity = 0.03; NDA 4th vs. 2nd quartile OR 0.54, 95% CI 0.41-0.70 vs. OR 0.71, 95% CI 0.59-0.85, p-heterogeneity = 0.07). However, there were no differences in the association of DA with breast cancer by aggressive status. In the stratified analysis, there was also evidence of a stronger association of PD and NDA with aggressive tumors among postmenopausal women and, in particular, current estrogen+progesterone users (≥51 vs. 11-25% OR 3.24, 95% CI 1.75-6.00 vs. OR 1.93, 95% CI 1.25-2.98, p-heterogeneity = 0.01; NDA 4th vs. 2nd quartile OR 0.43, 95% CI 0.21-0.85 vs. OR 0.56, 95% CI 0.35-0.89, p-heterogeneity = 0.01), even though the interaction was not significant. Our findings suggest that associations of mammographic

  3. Mammographic image reject rate analysis and cause – A National Maltese Study

    International Nuclear Information System (INIS)

    Mercieca, N.; Portelli, J.L.; Jadva-Patel, H.

    2017-01-01

    Mammography is used as a first-line investigation in the detection of breast cancer and imaging is required to be of optimal quality and achieved without adverse effects on the health of individuals. Repeated images come at a cost in terms of radiation dose, discomfort to clients and unnecessary financial burdens. No studies investigating mammography quality in Malta had been previously undertaken. Hence, this research aimed to investigate whether mammography is being performed at an acceptable level, through the investigation of reject rates. Quantitative methodology was used to collect data from eight participating mammography units, which were utilising screen film (SFM), computed radiography (CR) and direct digital mammography (DDM). Data relating to the total number of images performed, rejects and causes was prospectively collected over two weeks, resulting in a sample of 2291 images. All units were also asked to answer a questionnaire which provided other data that could be used for analysis. The national mammography reject rate was found to be 2.62%; within the 3% acceptable range. Individual rates' analysis revealed unacceptably high or low reject rates in some units. Positioning was the main reject cause. No significant difference in rejection was found between different types of mammography units or radiographers' experience. Alternatively, radiographers' qualifications, employment conditions and use of rejection criteria were proven to affect reject rates. Whilst on a national level, images are being rejected at an acceptable rate, individual units revealed suboptimal rates; at the cost of extra radiation, added discomfort and financial burden. - Highlights: • The national reject rate complied with the European Guidelines. • Reject rates in different units were found to vary. • Positioning was the commonest cause for repeats. • The equipment used and radiographers' experience did not affect reject rates. • Qualifications

  4. Fast transient digitizer

    International Nuclear Information System (INIS)

    Villa, F.

    1982-01-01

    Method and apparatus for sequentially scanning a plurality of target elements with an electron scanning beam modulated in accordance with variations in a high-frequency analog signal to provide discrete analog signal samples representative of successive portions of the analog signal; coupling the discrete analog signal samples from each of the target elements to a different one of a plurality of high speed storage devices; converting the discrete analog signal samples to equivalent digital signals; and storing the digital signals in a digital memory unit for subsequent measurement or display

  5. 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)

  6. 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)

  7. Digital communication system

    Science.gov (United States)

    Monford, L. G., Jr. (Inventor)

    1974-01-01

    A digital communication system is reported for parallel operation of 16 or more transceiver units with the use of only four interconnecting wires. A remote synchronization circuit produces unit address control words sequentially in data frames of 16 words. Means are provided in each transceiver unit to decode calling signals and to transmit calling and data signals. The transceivers communicate with each other over one data line. The synchronization unit communicates the address control information to the transceiver units over an address line and further provides the timing information over a clock line. A reference voltage level or ground line completes the interconnecting four wire hookup.

  8. Quality assurance in digital radiography

    International Nuclear Information System (INIS)

    Busch, H.P.; Lehmann, K.J.

    1989-01-01

    At present, there is no standard way of evaluating performance characteristics of digital radiography systems. Continuous measurements of performance parameters are necessary in order to obtain images of high quality. Parameters of quality assurance in digital radiography, which can be evaluated with simple, quick methods, are spatial resolution, low-contrast detectability, dynamic range and exposure dose. Spatial resolution was determined by a lead bar pattern, whereas the other parameters were measured by commercially available phantoms. Performance measurements of 10 digital subtraction angiography (DSA) units and one digital radiography system for unsubtracted digital radiography were assessed. From these results, recommendations for performance parameter levels will be discussed. (author)

  9. Mammographic Features of Local Recurrence after Conservative Surgery and Radiation Therapy: Comparison with that of the Primary Tumor

    International Nuclear Information System (INIS)

    Guenhan-Bilgen, I.; Oktay, A.

    2007-01-01

    Purpose: To compare the mammographic features of recurrent breast cancer with those of the primary tumor and to determine whether certain mammographic features are associated with a higher risk of local recurrence after breast-conserving therapy. Material and Methods: A retrospective review of mammograms of 421 patients who were treated with conservative surgery and radiotherapy revealed 41 recurrent tumors. Mammographic findings, location, and histopathologic characteristics were retrospectively compared between primary and recurrent tumors. Results: Recurrent tumors were similar in mammographic appearance to primary tumors in 27 (66%) cases. Of 27 primary tumors that occurred as masses without calcifications, 19 (70%) recurred as a mass, and of the six isolated calcifications, five (83%) recurred with calcifications. Ten (53%) of the 19 recurrent masses and five (100%) of the five recurrent calcifications had morphologic features that were similar to those of the primary tumor. Ninety-two percent (11/12) of the recurrences containing microcalcifications (isolated or associated with a mass) had microcalcifications in their primary tumor. Of 27 masses that recurred, the morphology of the primary tumor was obscured in 13 (48%), ill defined in 10 (37%), and spiculated in four (15%) of the masses. Seventy-six percent (31/41) of recurrences were within the lumpectomy quadrant. In 25 (61%) cases, the histologic findings from the primary tumor and the recurrence were identical. Conclusion: The majority of recurrent tumors appear to be mammographically similar to primary tumors. Therefore, it is important to review preoperative mammograms during follow-up of these patients. Although the study population is small, it was noted that mass with spiculated contour is associated with a lower risk for local recurrence

  10. Digital radiography

    International Nuclear Information System (INIS)

    Brody, W.R.

    1984-01-01

    Digital Radiography begins with an orderly introduction to the fundamental concepts of digital imaging. The entire X-ray digital imagining system is described, from an overall characterization of image quality to specific components required for a digital radiographic system. Because subtraction is central to digital radiographic systems, the author details the use of various subtraction methods for image enhancement. Complex concepts are illustrated with numerous examples and presented in terms that can readily be understood by physicians without an advanced mathematics background. The second part of the book discusses implementations and applications of digital imagining systems based on area and scanned detector technologies. This section includes thorough coverage of digital fluoroscopy, scanned projection radiography, and film-based digital imaging systems, and features a state-of-the-art synopsis of the applications of digital subtraction angiography. The book concludes with a timely assessment of anticipated technological advances

  11. EnviroAtlas - Frequency and Density of Candidate Areas for Ecological Restoration by 12-digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the number and density of candidate areas for ecological restoration in each 12-digit HUC. Ecological restoration may become a more...

  12. Digital Culture and Digital Library

    Directory of Open Access Journals (Sweden)

    Yalçın Yalçınkaya

    2016-12-01

    Full Text Available In this study; digital culture and digital library which have a vital connection with each other are examined together. The content of the research consists of the interaction of culture, information, digital culture, intellectual technologies, and digital library concepts. The study is an entry work to integrity of digital culture and digital library theories and aims to expand the symmetry. The purpose of the study is to emphasize the relation between the digital culture and digital library theories acting intersection of the subjects that are examined. Also the perspective of the study is based on examining the literature and analytical evaluation in both studies (digital culture and digital library. Within this context, the methodology of the study is essentially descriptive and has an attribute for the transmission and synthesis of distributed findings produced in the field of the research. According to the findings of the study results, digital culture is an inclusive term that describes the effects of intellectual technologies in the field of information and communication. Information becomes energy and the spectrum of the information is expanding in the vertical rise through the digital culture. In this context, the digital library appears as a new living space of a new environment. In essence, the digital library is information-oriented; has intellectual technology support and digital platform; is in a digital format; combines information resources and tools in relationship/communication/cooperation by connectedness, and also it is the dynamic face of the digital culture in time and space independence. Resolved with the study is that the digital libraries are active and effective in the formation of global knowing and/or mass wisdom in the process of digital culture.

  13. Mammographic and ultrasound features of invasive lobular carcinoma of the breast

    International Nuclear Information System (INIS)

    Porter, Alan J.; Evans, Elizabeth B.; Foxcraft, Loani M.; Simpson, Peter T.; Lakhani, Sunil R.

    2014-01-01

    Invasive lobular cancer (ILC) is an important contributor to false negative mammography. This study aims to assess the value of digital mammography and to identify imaging features that could assist the radiologist to suggest the diagnosis of ILC prior to biopsy. Three hundred sixty-one cases of pure ILC diagnosed at the Wesley Breast Clinic during the period 1995–2010 were reviewed by one of the authors (AP). Radiological features were categorized, and clinical features and needle sampling results were recorded. Mammography was negative in 29.9% of ILCs. The commonest positive finding was a localized spiculated mass (41.8%). Thirty-four point nine per cent of lesions were visible in only one view, usually cranio-caudal. Calcification was not a feature of ILC. The use of digital mammography in 30% of cases did not decrease the false negative rate for ILC. Breast ultrasound (BUS) showed an abnormality in 97.8%, most commonly a localized irregular hypoechoic mass with shadowing. Digital mammography does not reduce false negative mammography in ILC. The poor visibility of ILCs may be partly related to their low density (mass/unit volume). ILCs may sometimes be poor attenuators of X-rays but excellent attenuators of ultrasound, causing marked acoustic shadowing. Bilateral whole BUS has a very low false negative rate in experienced hands and is mandatory in symptomatic women. The combination of poor visibility on mammography with high visibility on ultrasound, as well as certain characteristic ultrasound appearances of ILC, may enable the radiologist to suggest ILC as a diagnostic possibility, prior to biopsy.

  14. Diagnostic imaging of lobular carcinoma of the breast. Mammographic, US and MR findings

    International Nuclear Information System (INIS)

    Bazzocchi, M.; Facecchia, I.; Zuiani, C.; Smania, S.; Puglisi, F.; Di Loreto, C.

    2000-01-01

    Purpose of this article is to evaluate the most frequent mammographic, US and MR findings of invasive lobular carcinoma and the role of MRI in defining multifocality and/or multi centricity of this tumor histotype. 45 lobular carcinomas in 39 patients were studied and selected from 421 breast cancers. Core biopsy with a 14G needle was performed in 39 cases, under US guidance in 36/39 and under mammographic guidance in 3/39 cases. Surgical biopsy was performed in 2 cases and the diagnosis could be made only after mastectomy in 5 cases. All patients were examined with mammography and US and (10-13 MHz) and 8 also with MRI. 28/46 palpable lesions (60.9%). Core biopsy correctly diagnosed 38/39 lesions (97.4%). The most frequent mammographic findings was that of a nodular opacity without microcalcifications (34.8%), followed by a mass with spiculate d borders (30.4%). Microcalcifications were seen in one case only (2.2%). Mammography detected no abnormalities in 15.2% of cases, but US showed a lesion in 2 of these cases. The most frequent US pattern was that of a hypoechoic lesion (43.5%), followed by posterior US beam attenuation. No US signs of abnormality were seen 15.2%. MRI correctly detected 13 lesions. Contrast enhancement was greater than 70% at one minute in 10 cases and greater than 40% in one case; two lesions exhibited atypical slow contrast enhancement, peaking at 5 minutes. MRI detected 5 lesions missed both mammography and US and showed multifocal (3 and 2) lesions where the other techniques had detected one lesion only. At mammography and US invasive lobular carcinoma exhibits no different features than ductal carcinoma but is difficult to identify especially in its early stages. US is a useful tool especially to characterize mammography-detected lesions but in the experience it also demonstrated 2 lesions missed at mammography. MRI is a precious examination to define the multifocal, multi centric or bilateral character of invasive lobular carcinoma

  15. Mammographic density and risk of breast cancer by tumor characteristics: a case-control study.

    Science.gov (United States)

    Krishnan, Kavitha; Baglietto, Laura; Stone, Jennifer; McLean, Catriona; Southey, Melissa C; English, Dallas R; Giles, Graham G; Hopper, John L

    2017-12-16

    In a previous paper, we had assumed that the risk of screen-detected breast cancer mostly reflects inherent risk, and the risk of whether a breast cancer is interval versus screen-detected mostly reflects risk of masking. We found that inherent risk was predicted by body mass index (BMI) and dense area (DA) or percent dense area (PDA), but not by non-dense area (NDA). Masking, however, was best predicted by PDA but not BMI. In this study, we aimed to investigate if these associations vary by tumor characteristics and mode of detection. We conducted a case-control study nested within the Melbourne Collaborative Cohort Study of 244 screen-detected cases matched to 700 controls and 148 interval cases matched to 446 controls. DA, NDA and PDA were measured using the Cumulus software. Tumor characteristics included size, grade, lymph node involvement, and ER, PR, and HER2 status. Conditional and unconditional logistic regression were applied as appropriate to estimate the Odds per Adjusted Standard Deviation (OPERA) adjusted for age and BMI, allowing the association with BMI to be a function of age at diagnosis. For screen-detected cancer, both DA and PDA were associated to an increased risk of tumors of large size (OPERA ~ 1.6) and positive lymph node involvement (OPERA ~ 1.8); no association was observed for BMI and NDA. For risk of interval versus screen-detected breast cancer, the association with risk for any of the three mammographic measures did not vary by tumor characteristics; an association was observed for BMI for positive lymph nodes (OPERA ~ 0.6). No associations were observed for tumor grade and ER, PR and HER2 status of tumor. Both DA and PDA were predictors of inherent risk of larger breast tumors and positive nodal status, whereas for each of the three mammographic density measures the association with risk of masking did not vary by tumor characteristics. This might raise the hypothesis that the risk of breast tumours with poorer prognosis

  16. Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density.

    Science.gov (United States)

    Chew, G L; Huo, C W; Huang, D; Hill, P; Cawson, J; Frazer, H; Hopper, J L; Haviv, I; Henderson, M A; Britt, K; Thompson, E W

    2015-08-01

    Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast ca