Rationale And Objectives: Synthesized mammography with digital breast tomosynthesis (SM+DBT) and full-field digital mammography with DBT were prospectively evaluated for recall rate (RR), cancer detection rate (CDR), positive predictive value 1 (PPV1), lesion recall differences, and disagreements in recall for additional imaging.
Materials And Methods: From December 15, 2015 to January 15, 2017, after informed consent was obtained for this Health Insurance Portability and Accountability Act compliant study, each enrolled patient's SM+DBT and FFDM+DBT were interpreted sequentially by one of eight radiologists. RR, CDR, PPV1, and imaging findings (asymmetry, focal asymmetry, mass, architectural distortion, and calcifications) recalled were reviewed.
Computer-aided detection (CAD) alerts radiologists to findings potentially associated with breast cancer but is notorious for creating false-positive marks. Although a previous paper found that radiologists took more time to interpret mammograms with more CAD marks, our impression was that this was not true in actual interpretation. We hypothesized that radiologists would selectively disregard these marks when present in larger numbers.
View Article and Find Full Text PDFPurpose: Grid artifacts occur in digital mammography when synchronization between the grid assembly and generator is not achieved, including when malfunctions occur in the grid assembly or generator subsystems. Such artifacts are not explicitly monitored or evaluated by existing mammography quality control programs. In this study, we developed an automated method for quantifying the presence of grid artifacts in two-dimensional (2D) digital mammography images and assessed its utility as a supplement to existing quality control programs.
View Article and Find Full Text PDFObjective: Artifacts in digital breast tomosynthesis and synthesized 2D imaging reduce image quality. This article describes the appearance of these unique artifacts, reviews their causes, and discusses methods to ameliorate these artifacts.
Conclusion: Artifacts in digital breast tomosynthesis and synthesized 2D imaging can obscure important findings on mammograms.
Objective: To determine whether the type of projection used-same as or orthogonal to the projection used during a stereotactic-guided core needle biopsy procedure-to obtain the first view on a 2-view postbiopsy mammogram affects biopsy marker clip migration.
Patients And Methods: We prospectively recruited women scheduled to undergo stereotactic-guided core needle breast biopsy with marker clip deployment and categorized the women randomly into one of the following 2 groups: first view on the postbiopsy mammogram obtained in the same projection as that used during the biopsy procedure (group 1), or first view on the postbiopsy mammogram obtained orthogonally to the projection used during the biopsy procedure (group 2). Masks of the prebiopsy and postbiopsy mammograms were used to determine whether and how far the biopsy marker clip moved from the biopsy cavity.
Quality control (QC) in medical imaging is an ongoing process and not just a series of infrequent evaluations of medical imaging equipment. The QC process involves designing and implementing a QC program, collecting and analyzing data, investigating results that are outside the acceptance levels for the QC program, and taking corrective action to bring these results back to an acceptable level. The QC process involves key personnel in the imaging department, including the radiologist, radiologic technologist, and the qualified medical physicist (QMP).
View Article and Find Full Text PDFJ Opt Soc Am A Opt Image Sci Vis
November 2014
Current literature shows that radiologist experience does not affect detection tasks when the object does not require medical training to detect. However, the research was never sufficiently detailed to examine if the contrast detection threshold is also the same for radiologists versus nonradiologists. Previously, contrast threshold research was performed predominantly on nonradiologists.
View Article and Find Full Text PDFThe radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population.
View Article and Find Full Text PDFThe purpose of this study was to evaluate stereoscopic perception of low-dose breast tomosynthesis projection images. In this Institutional Review Board exempt study, craniocaudal breast tomosynthesis cases (N = 47), consisting of 23 biopsy-proven malignant mass cases and 24 normal cases, were retrospectively reviewed. A stereoscopic pair comprised of two projection images that were ±4° apart from the zero angle projection was displayed on a Planar PL2010M stereoscopic display (Planar Systems, Inc.
View Article and Find Full Text PDFObjective: The purpose of this article is to describe how to establish a cost-effective mobile mammography program on the basis of examples from a 20-year experience with film-screen and digital mammography units.
Conclusion: Mobile mammography programs can reduce many barriers to breast cancer screening faced by medically underserved women. Finding and maintaining resources, having appropriate equipment and infrastructure, and having a dedicated team with an efficient workflow are the key elements of establishing a cost-effective mobile mammography program.
Published information on contrast detection threshold is based primarily on research using a location-known methodology. In previous work on testing the Digital Imaging and Communications in Medicine (DICOM) Grayscale Standard Display Function (GSDF) for perceptual linearity, this research group used a location-unknown methodology to more closely reflect clinical practice. A high false-positive rate resulted in a high variance leading to the conclusion that the impact on results of employing a location-known methodology needed to be explored.
View Article and Find Full Text PDFWhile previous research has determined the contrast detection threshold in medical images, it has focused on uniform backgrounds, has not used calibrated monitors, or has involved a low number of readers. With complex clinical images, how the Grayscale Standard Display Function (GSDF) affects the detection threshold and whether the median background intensity shift has been minimized by GSDF remains unknown. We set out to determine if the median background affected the detection of a low-contrast object in a clustered lumpy background, which simulated a mammography image, and to define the contrast detection threshold for these complex images.
View Article and Find Full Text PDFPurpose: The scan equalization digital mammography (SEDM) technique combines slot scanning and exposure equalization to improve low-contrast performance of digital mammography in dense tissue areas. In this study, full-field digital mammography (FFDM) images of an anthropomorphic breast phantom acquired with an anti-scatter grid at various exposure levels were superimposed to simulate SEDM images and investigate the improvement of low-contrast performance as quantified by primary signal-to-noise ratios (PSNRs).
Methods: We imaged an anthropomorphic breast phantom (Gammex 169 "Rachel," Gammex RMI, Middleton, WI) at various exposure levels using a FFDM system (Senographe 2000D, GE Medical Systems, Milwaukee, WI).
AJR Am J Roentgenol
December 2011
Objective: Early detection of breast cancer is directly related to the radiologist's ability to detect abnormalities visible only on mammograms. Artifacts on mammograms reduce image quality and may present clinical and technical difficulties for the radiologist, mammography technologist, medical physicist, and equipment service personnel.
Conclusion: In this article, we will illustrate the appearance of artifacts in full field digital mammography, review the causes of these artifacts, and discuss methods to eliminate artifacts in digital mammography.
Purpose: To prospectively determine the interpretation time associated with computer-aided detection (CAD) and to analyze how CAD affected radiologists' decisions and their level of confidence in their interpretations of digital screening mammograms.
Materials And Methods: An Institutional Review Board exemption was obtained, and patient consent was waived in this HIPAA compliant study. The participating radiologists gave informed consent.
Rationale And Objectives: American College of Radiology guidelines suggest that digital screening mammographic images should be viewed at the full resolution at which they were acquired. This slows interpretation speed. The aim of this study was to examine the effect of various levels of zooming on the detection and conspicuity of microcalcifications.
View Article and Find Full Text PDFThe purpose of this study was to evaluate and compare microcalcification detectability of two commercial full-field digital mammography (DM) systems. The first unit was a flat panel based DM system (FFDM) which employed an anti-scatter grid method to reject scatter, and the second unit was a charge-coupled device-based DM system (SSDM) which used scanning slot imaging geometry to reduce scatter radiation. Both systems have comparable scatter-to-primary ratios.
View Article and Find Full Text PDFThe purpose of this study was to evaluate the use of digital x-ray imaging detectors for the measurement of diagnostic x-ray tube focal spot size using a slit camera. Slit camera images of two focal spots for a radiographic x-ray tube were acquired with direct-exposure film (DF) (as specified by the National Electrical Manufacturers Association [NEMA] Standards Publication No. XR 5, 1992), computed radiography (CR) imaging plates, and an a-Si:H/CsI:Tl-based flat-panel (FP) detector.
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