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BMJ (Clinical Research Ed.) Oct 1998
Topics: Adult; Attitude to Health; Consensus Development Conferences as Topic; Female; Health Services Accessibility; History, 20th Century; Humans; Mammography; Middle Aged; Patient Education as Topic; Politics; Practice Guidelines as Topic; Public Opinion; Randomized Controlled Trials as Topic; United States
PubMed: 9794866
DOI: 10.1136/bmj.317.7167.1224 -
Health Physics Nov 2008The art, science, and technology of mammography have developed steadily over the past 35 y. Mammography is a central tool for diagnosis of symptoms of breast cancer. In...
The art, science, and technology of mammography have developed steadily over the past 35 y. Mammography is a central tool for diagnosis of symptoms of breast cancer. In addition, periodic screening of asymptomatic women in certain age groups has been clearly demonstrated to contribute to reduction of mortality from breast cancer. Technical improvements have allowed the examination to be carried out at substantially lower radiation dose than was necessary to obtain a good image in the 1970's, while at the same time providing greatly improved contrast, spatial resolution, dynamic range and tissue coverage. Digital mammography overcomes many of the technical limitations inherent in screen-film mammography and has been shown to offer increased accuracy for women under 50 and those with dense breasts. The radiation risk associated with mammography cannot be ignored, however, modern analysis suggests that it is very low, especially compared to the benefits from the exam. Nevertheless, imaging should be conducted with careful attention to efficient use of the radiation. New techniques, currently under development and evaluation, promise to add further to the value of mammography.
Topics: Breast; Breast Neoplasms; Equipment Design; Female; Humans; Mammography; Radiation Dosage
PubMed: 18849694
DOI: 10.1097/01.HP.0000327648.42431.75 -
Medical Physics Mar 2000Monte Carlo simulations of digital images of the contrast detail phantom and the ACR phantom are presented for two different x-ray digital mammography modalities: a... (Comparative Study)
Comparative Study
Monte Carlo simulations of digital images of the contrast detail phantom and the ACR phantom are presented for two different x-ray digital mammography modalities: a synchrotron mammography system and a next-generation scanning slot clinical system. A combination of variance reduction methods made it possible to simulate accurate images using real pixel dimensions within reasonable computation times. The complete method of image simulation, including a simple detector response model, a simple noise model, and the incorporation of system effects (MTF), is presented. The simulated images of the phantoms show good agreement with images measured on the two systems.
Topics: Algorithms; Mammography; Monte Carlo Method; Phantoms, Imaging; Radiographic Image Interpretation, Computer-Assisted; Scattering, Radiation; Software; Synchrotrons
PubMed: 10757608
DOI: 10.1118/1.598896 -
Radiologic Clinics of North America Jan 1992Two improvements in mammography equipment during the last 4 years will greatly affect the practice of mammography during the next decade: dose reduction and improved... (Review)
Review
Two improvements in mammography equipment during the last 4 years will greatly affect the practice of mammography during the next decade: dose reduction and improved testing equipment for monitoring the quality of mammography. The increased use of digital radiography has stimulated studies comparing digital mammography with screen-film mammography. Some digital algorithms for detecting clusters of calcifications may have application in screening mammography within the next decade.
Topics: Female; Humans; Mammography; X-Ray Intensifying Screens
PubMed: 1732935
DOI: No ID Found -
Ugeskrift For Laeger Jul 1991
Topics: Denmark; Female; Humans; Mammography; Mass Screening
PubMed: 1858195
DOI: No ID Found -
Health Devices 1990This evaluation was a cooperative effort between ECRI and the Swedish Testing Institute for Medical Supplies (Sprima AB), Stockholm. As noted in our last mammography...
This evaluation was a cooperative effort between ECRI and the Swedish Testing Institute for Medical Supplies (Sprima AB), Stockholm. As noted in our last mammography evaluation, we are initially focusing on mammography units in our series of radiology and imaging studies because (1) improvements in technology (e.g., lower radiation doses) now make routine screening feasible; (2) third-party payers are supporting screening programs, and (3) breast cancer is a major threat to women's health. Again ECRI will provide physicists and radiologists with our raw test data on request. In our previous evaluation, we discussed the role of mammography in reducing breast cancer mortality rates and tested the units for screen-film mammography and xeromammography capability, basing our ratings primarily on the units' ability to safely and consistently produce acceptable images with minimal patient dose during screen-film mammography. Below, we focus on the definition, measurement, and significance of image quality within the context of screen-film mammography. We evaluated seven mammography units from seven manufacturers. We also retested the Automatic Exposure Control (AEC) mode of the Soredex Mamex dc Mag, which we evaluated last year and rated Conditionally Acceptable because of its AEC performance (see "Soredex Mamex dc Mag"). Our ratings are based on our minimum criteria of acceptability: that the units safely and reliably produce the best possible image quality while delivering the lowest possible dose to the patient. Except for the Kramex HF-45, all of the evaluated units-the Acoma ESP-200, GE-CGR Senographe 600T, Instrumentarium/Ausonics (I/A) Alpha III, Lorad M II-D, Philips MammoDiagnost UC, Picker Sureview, and the Soredex Mamex dc Mag-exceed our minimum criteria and are rated Acceptable for both screening and magnification (diagnostic) applications. The Kramex HF-45, the only dedicated screening unit we evaluated, is rated Acceptable-Not Recommended because of its limitations in achieving optimal image quality. The units are ranked according to their AEC performance and human factors (ergonomic) design, as well as on technical phantom image quality results, within the two applications. Clinical phantom image quality results are listed, but were not used to rank the units. Refer to our previous study for further discussions of breast imaging technology and terminology, as well as radiation risks. Terms set below in small caps are defined in the Glossary.
Topics: Equipment Design; Evaluation Studies as Topic; Female; Humans; Mammography; Quality Assurance, Health Care; Radiographic Image Enhancement; Technology Assessment, Biomedical
PubMed: 2372321
DOI: No ID Found -
Health Expectations : An International... Aug 2017There is substantial expert disagreement about the use of mammography to screen for breast cancer, and this disagreement routinely plays out in the media. Evidence...
BACKGROUND
There is substantial expert disagreement about the use of mammography to screen for breast cancer, and this disagreement routinely plays out in the media. Evidence suggests that some women are aware of the controversy over mammography, but less is known about whether immigrant and other underserved women have heard about it and, if so, how they react to it.
OBJECTIVE
To explore immigrant women's awareness of and reactions to mammography controversy.
DESIGN
Community-engaged qualitative study: we conducted six focus groups with 53 women aged 35-55 from three immigrant communities (Somali, Latina and Hmong) in a major US metropolitan area. A grounded theory approach was used to identify themes; NVivo 10 was used to enhance analyses.
RESULTS
Several themes emerged: (i) low awareness of mammography controversy across groups, despite self-reported attention to health information; (ii) high intentions to be screened, even after being told about the controversy; (iii) few reported discussions of mammography's risks and benefits with clinicians; (iv) substantial interest in learning more about mammography and breast cancer, but some low self-efficacy to obtain such information; and (v) questions about whether health recommendations matter and what qualifies as evidence.
CONCLUSION
Given on-going expert disagreement about mammography screening, it is important for clinicians to help women understand mammography's risks and benefits so they can make an informed choice. This is particularly critical for immigrant and other underserved women, who may be less able to access, attend to, process, retain and act on health information (a phenomenon known as communication inequality).
Topics: Adult; Awareness; Breast Neoplasms; Early Detection of Cancer; Emigrants and Immigrants; Ethnicity; Female; Focus Groups; Health Knowledge, Attitudes, Practice; Humans; Mammography; Middle Aged; Socioeconomic Factors; United States
PubMed: 27561593
DOI: 10.1111/hex.12494 -
Radiation Protection Dosimetry Nov 2017The aim of this study is to explore the use of a quality (Q) factor in digital mammography as a figure-of-merit. Q factors take a reference value into account and can be... (Comparative Study)
Comparative Study
The aim of this study is to explore the use of a quality (Q) factor in digital mammography as a figure-of-merit. Q factors take a reference value into account and can be compared to a theoretical value. They are also intended to summarise the performance of any unit based on a number. The mean glandular dose (MGD)-normalised Q factors were also introduced based on the relationship of the Q factors with MGD. Interestingly, the automatic exposure control exposures did not render the maximum normalised Q factor values as expected, which could indicate the need for further optimisation. It was also noted that the Q factors and the CDMAM-related quality parameters can be confidently predicted for a given MGD which in turn may be compared to the measured values. This might be another way to consider or perform optimisation in digital mammography.
Topics: Equipment Design; Female; Humans; Mammography; Phantoms, Imaging; Radiation Dosage; Radiographic Image Interpretation, Computer-Assisted; Reference Values
PubMed: 28338934
DOI: 10.1093/rpd/ncx022 -
Medical Care Dec 2012Digital mammography is the dominant modality for breast cancer screening in the United States. No previous studies have investigated as to how introducing digital...
BACKGROUND
Digital mammography is the dominant modality for breast cancer screening in the United States. No previous studies have investigated as to how introducing digital mammography affects downstream breast-related care.
OBJECTIVE
Compare breast-related health care use after a screening mammogram before and after introduction of digital mammography.
RESEARCH DESIGN AND SUBJECTS
Longitudinal study of screening mammograms from 14 radiology facilities contributing data to the Breast Cancer Surveillance Consortium performed 1 year before and 4 years after each facility introduced digital mammography, along with linked Medicare claims. We included 30,211 mammograms for women aged 66 years and older without breast cancer.
MEASURES
Rates of false-positive recall and short-interval follow-up were based on radiologists' assessments and recommendations; rates of follow-up mammography, ultrasound, and breast biopsy use were based on Medicare claims.
RESULTS
False-positive recall rates increased after the introduction of digital mammography. Follow-up mammography use was significantly higher across all 4 years after a facility began using digital mammography compared with the year before [year 1 odds ratio (OR) = 1.7, 95% confidence interval (CI), 1.4-2.1]. Among women with false-positive mammography results, use of ultrasound decreased significantly in the second through fourth years after digital mammography began (year 2 OR = 0.4, 95% CI, 0.3-0.6).
CONCLUSIONS
Introduction of a new technology led to changes in health care use that persisted for at least 4 years. Comparative effectiveness research on new technologies should consider not only diagnostic performance but also downstream utilization attributable to this apparent learning curve.
Topics: Aged; Aged, 80 and over; Breast Neoplasms; Comparative Effectiveness Research; False Positive Reactions; Female; Humans; Insurance Claim Review; Mammography; Medicare; Radiographic Image Enhancement; Retrospective Studies; United States
PubMed: 23132199
DOI: 10.1097/MLR.0b013e318269e9c2 -
Investigative Radiology Jan 2005The emission spectrum of an x-ray tube is determined by the anode and filter materials as well as by the high voltage being used. For mammography, typical anode...
RATIONALE AND BACKGROUND
The emission spectrum of an x-ray tube is determined by the anode and filter materials as well as by the high voltage being used. For mammography, typical anode materials are molybdenum (Mo), rhodium (Rh), and tungsten (W); molybdenum, rhodium, and aluminum are favored for filters. Mammography is a soft tissue imaging modality demanding a high spatial resolution as well as a high detector sensitivity. Low-energy photons are only absorbed in tissue and have no contribution to the image; nevertheless, they increase the dose. High-energy photons mostly penetrate soft tissue and generate a background noise as a result of strong scattering that deteriorates the image quality. For mammography, the optimal energy window is in a range from 17 and 25 keV. From a theoretical perspective, one would favor monoenergetic x-rays (eg, the Mo-emission line at 17.5 keV). This article presents the realization of imaging with monochromatic x-rays using a diagnostic mammography unit.
METHODS
Basically, a monochromatic module was added to a conventional mammographic system. The monochromatic module can be mounted at the end of the x-ray tube and it consists of a curved HOPG (highly oriented pyrolytic graphite) crystal and a slit collimator. For image generation, the object is moved through the fan-shaped monochromatic radiation field. In addition to the conventional polychromatic 2-dimensional case, the polychromatic irradiation was also able to be performed under similar conditions. For image acquisition, image plates or a linear array detector were used. Exposure doses were measured for both poly- and monochromatic radiation. The initial evaluation of the system performance was carried out by imaging a contrast-detail phantom and biologic specimens.
RESULTS
The monochromatic x-ray beam has a size of approximately 35 mm x 200 mm in the object plane. The photon flux of the monochromatic x-rays is considerably lower than the photon flux of the polychromatic x-rays but adequate for initial studies of phantoms, biologic tissue, or small animals. The comparison of the results obtained with the monochromatic and polychromatic imaging modalities reveal a conspicuous increase of image contrast in the monochromatic case.
CONCLUSION
The results suggest that the experimental setup for monochromatic excitation shows clear potentials for improvements of the image in comparison to the conventional polychromatic case.
Topics: Equipment Design; Mammography; Radiographic Image Enhancement
PubMed: 15597018
DOI: No ID Found