Computer-aided detection system applied to full-field digital mammograms

Energy Technology Data Exchange (ETDEWEB)

Vega Bolivar, Alfonso; Sanchez Gomez, Sonia; Merino, Paula; Alonso-Bartolome, Pilar; Ortega Garcia, Estrella (Dept. of Radiology, Univ. Marques of Valdecilla Hospital, Santander (Spain)), e-mail: avegab@telefonica.net; Munoz Cacho, Pedro (Dept. of Statistics, Univ. Marques of Valdecilla Hospital, Santander (Spain)); Hoffmeister, Jeffrey W. (iCAD, Inc., Nashua, NH (United States))

2010-12-15

Background: Although mammography remains the mainstay for breast cancer screening, it is an imperfect examination with a sensitivity of 75-92% for breast cancer. Computer-aided detection (CAD) has been developed to improve mammographic detection of breast cancer. Purpose: To retrospectively estimate CAD sensitivity and false-positive rate with full-field digital mammograms (FFDMs). Material and Methods: CAD was used to evaluate 151 cases of ductal carcinoma in situ (DCIS) (n=48) and invasive breast cancer (n=103) detected with FFDM. Retrospectively, CAD sensitivity was estimated based on breast density, mammographic presentation, histopathology type, and lesion size. CAD false-positive rate was estimated with screening FFDMs from 200 women. Results: CAD detected 93% (141/151) of cancer cases: 97% (28/29) in fatty breasts, 94% (81/86) in breasts containing scattered fibroglandular densities, 90% (28/31) in heterogeneously dense breasts, and 80% (4/5) in extremely dense breasts. CAD detected 98% (54/55) of cancers manifesting as calcifications, 89% (74/83) as masses, and 100% (13/13) as mixed masses and calcifications. CAD detected 92% (73/79) of invasive ductal carcinomas, 89% (8/9) of invasive lobular carcinomas, 93% (14/15) of other invasive carcinomas, and 96% (46/48) of DCIS. CAD sensitivity for cancers 1-10 mm was 87% (47/54); 11-20 mm, 99% (70/71); 21-30 mm, 86% (12/14); and larger than 30 mm, 100% (12/12). The CAD false-positive rate was 2.5 marks per case. Conclusion: CAD with FFDM showed a high sensitivity in identifying cancers manifesting as calcifications or masses. CAD sensitivity was maintained in small lesions (1-20 mm) and invasive lobular carcinomas, which have lower mammographic sensitivity

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...

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.

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)

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.

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.

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

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.

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.

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

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

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

Low energy mammogram obtained in contrast-enhanced digital mammography (CEDM) is comparable to routine full-field digital mammography (FFDM)

Energy Technology Data Exchange (ETDEWEB)

Francescone, Mark A., E-mail: maf2184@columbia.edu [Columbia University Medical Center, ColumbiaDoctors Midtown, 51 West 51st Street, Suite 300, New York, NY 10019 (United States); Jochelson, Maxine S., E-mail: jochelsm@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Dershaw, D. David, E-mail: dershawd@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Sung, Janice S., E-mail: sungj@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Hughes, Mary C., E-mail: hughesm@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Zheng, Junting, E-mail: zhengj@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Moskowitz, Chaya, E-mail: moskowc1@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Morris, Elizabeth A., E-mail: morrise@mskcc.org [Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States)

2014-08-15

Purpose: Contrast enhanced digital mammography (CEDM) uses low energy and high energy exposures to produce a subtracted contrast image. It is currently performed with a standard full-field digital mammogram (FFDM). The purpose is to determine if the low energy image performed after intravenous iodine injection can replace the standard FFDM. Methods: And Materials: In an IRB approved HIPAA compatible study, low-energy CEDM images of 170 breasts in 88 women (ages 26–75; mean 50.3) undergoing evaluation for elevated risk or newly diagnosed breast cancer were compared to standard digital mammograms performed within 6 months. Technical parameters including posterior nipple line (PNL) distance, compression thickness, and compression force on the MLO projection were compared. Mammographic findings were compared qualitatively and quantitatively. Mixed linear regression using generalized estimating equation (GEE) method was performed. Intraclass correlation coefficients (ICC) with 95% confidence interval (95%CI) were estimated to assess agreement. Results: No statistical difference was found in the technical parameters compression thickness, PNL distance, compression force (p-values: 0.767, 0.947, 0.089). No difference was found in the measured size of mammographic findings (p-values 0.982–0.988). Grouped calcifications had a mean size/extent of 2.1 cm (SD 0.6) in the low-energy contrast images, and a mean size/extent of 2.2 cm (SD 0.6) in the standard digital mammogram images. Masses had a mean size of 1.8 cm (SD 0.2) in both groups. Calcifications were equally visible on both CEDM and FFDM. Conclusion: Low energy CEDM images are equivalent to standard FFDM despite the presence of intravenous iodinated contrast. Low energy CEDM images may be used for interpretation in place of the FFDM, thereby reducing patient dose.

Low energy mammogram obtained in contrast-enhanced digital mammography (CEDM) is comparable to routine full-field digital mammography (FFDM)

International Nuclear Information System (INIS)

Francescone, Mark A.; Jochelson, Maxine S.; Dershaw, D. David; Sung, Janice S.; Hughes, Mary C.; Zheng, Junting; Moskowitz, Chaya; Morris, Elizabeth A.

2014-01-01

Purpose: Contrast enhanced digital mammography (CEDM) uses low energy and high energy exposures to produce a subtracted contrast image. It is currently performed with a standard full-field digital mammogram (FFDM). The purpose is to determine if the low energy image performed after intravenous iodine injection can replace the standard FFDM. Methods: And Materials: In an IRB approved HIPAA compatible study, low-energy CEDM images of 170 breasts in 88 women (ages 26–75; mean 50.3) undergoing evaluation for elevated risk or newly diagnosed breast cancer were compared to standard digital mammograms performed within 6 months. Technical parameters including posterior nipple line (PNL) distance, compression thickness, and compression force on the MLO projection were compared. Mammographic findings were compared qualitatively and quantitatively. Mixed linear regression using generalized estimating equation (GEE) method was performed. Intraclass correlation coefficients (ICC) with 95% confidence interval (95%CI) were estimated to assess agreement. Results: No statistical difference was found in the technical parameters compression thickness, PNL distance, compression force (p-values: 0.767, 0.947, 0.089). No difference was found in the measured size of mammographic findings (p-values 0.982–0.988). Grouped calcifications had a mean size/extent of 2.1 cm (SD 0.6) in the low-energy contrast images, and a mean size/extent of 2.2 cm (SD 0.6) in the standard digital mammogram images. Masses had a mean size of 1.8 cm (SD 0.2) in both groups. Calcifications were equally visible on both CEDM and FFDM. Conclusion: Low energy CEDM images are equivalent to standard FFDM despite the presence of intravenous iodinated contrast. Low energy CEDM images may be used for interpretation in place of the FFDM, thereby reducing patient dose

Practical digital mammography

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-01

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

Practical digital mammography

International Nuclear Information System (INIS)

Hashimoto, Beverly E.

2008-01-01

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

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)

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.

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.)

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.

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.

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.

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.

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.

Performances of different digital mammography imaging systems: Evaluation and comparison

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

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

Performances of different digital mammography imaging systems: Evaluation and comparison

International Nuclear Information System (INIS)

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

2005-01-01

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

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

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)

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...

Mapping 3D breast lesions from full-field digital mammograms using subject-specific finite element models

Science.gov (United States)

García, E.; Oliver, A.; Diaz, O.; Diez, Y.; Gubern-Mérida, A.; Martí, R.; Martí, J.

2017-03-01

Patient-specific finite element (FE) models of the breast have received increasing attention due to the potential capability of fusing images from different modalities. During the Magnetic Resonance Imaging (MRI) to X-ray mammography registration procedure, the FE model is compressed mimicking the mammographic acquisition. Subsequently, suspicious lesions in the MRI volume can be projected into the 2D mammographic space. However, most registration algorithms do not provide the reverse information, avoiding to obtain the 3D geometrical information from the lesions localized in the mammograms. In this work we introduce a fast method to localize the 3D position of the lesion within the MRI, using both cranio-caudal (CC) and medio-lateral oblique (MLO) mammographic projections, indexing the tetrahedral elements of the biomechanical model by means of an uniform grid. For each marked lesion in the Full-Field Digital Mammogram (FFDM), the X-ray path from source to the marker is calculated. Barycentric coordinates are computed in the tetrahedrons traversed by the ray. The list of elements and coordinates allows to localize two curves within the MRI and the closest point between both curves is taken as the 3D position of the lesion. The registration errors obtained in the mammographic space are 9.89 +/- 3.72 mm in CC- and 8.04 +/- 4.68 mm in MLO-projection and the error in the 3D MRI space is equal to 10.29 +/- 3.99 mm. Regarding the uniform grid, it is computed spending between 0.1 and 0.7 seconds. The average time spent to compute the 3D location of a lesion is about 8 ms.

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

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

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.

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).

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.

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

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.

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.

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

Mammographic casting-type calcification associated with small screen-detected invasive breast cancers: is this a reliable prognostic indicator?

International Nuclear Information System (INIS)

Peacock, C.; Given-Wilson, R.M.; Duffy, S.W.

2004-01-01

AIM: The aim of the present study was to establish whether mammographic casting-type calcification associated with small screen-detected invasive breast cancers is a reliable prognostic indicator. METHODS AND MATERIALS: We retrospectively identified 50 consecutive women diagnosed with an invasive cancer less than 15 mm who showed associated casting calcification on their screening mammograms. Controls were identified that showed no microcalcification and were matched for tumour size, histological type and lymph node status. A minimum of 5 years follow-up was obtained, noting recurrence and outcome. Conditional and unconditional logistic regression, depending on the outcome variable, were used to analyse the data, taking the matched design into account in both cases. Where small numbers prohibited the use of logistic regression, Fisher's exact test was used. RESULTS: Five deaths from breast cancer occurred out of the 50 cases, of which three were lymph node positive, two were lymph node negative and none were grade 3. None of the 78 control cases died from breast cancer. The difference in breast cancer death rates was significant by Fisher's exact test (p=0.02). Risk of recurrence was also significantly increased in the casting cases (OR=3.55, 95% CI 1.02-12.33, p=0.046). CONCLUSION: Although the overall outcome for small screen-detected breast cancers is good, our study suggests that casting calcification is a poorer prognostic factor. The advantage of a mammographic feature as an independent prognostic indicator lies in early identification of high-risk patients, allowing optimization of management

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

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

International Nuclear Information System (INIS)

Skaane, P.

2009-01-01

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

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....

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

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

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

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)

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...

Is the presence of mammographic comedo calcification really a prognostic factor for small screen-detected invasive breast cancers?

International Nuclear Information System (INIS)

James, J.J.; Evans, A.J.; Pinder, S.E.; Macmillan, R.D.; Wilson, A.R.M.; Ellis, I.O.

2003-01-01

AIM: It has been suggested that the use of traditional prognostic factors such as histological grade and lymph node stage are not reliable predictors of outcome for small ( 2 = 9.68,P = 0.008). No significant association was demonstrated between the presence of comedo calcification and survival. Multivariate analysis confirmed lymph node stage as the only independent prognostic factor for these small screen-detected breast cancers (χ 2 = 7.18,P = 0.007). There were significant associations between the presence of comedo calcification on the screening mammogram and high histological grade and small tumour size. CONCLUSION: Although the overall outcome for small screen-detected breast cancers (<15 mm diameter) is excellent, the presence of lymph node metastases is associated with a significant reduction in long-term survival. The presence of mammographic comedo calcification is not an independent prognostic factor, but is closely related to histological grade. James, J. J. et al. (2003). Clinical Radiology, 58, 54-62

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)

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.

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.

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

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.

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.

Miniaturized digital fluxgate magnetometer for small spacecraft applications

International Nuclear Information System (INIS)

Forslund, Åke; Ivchenko, Nickolay; Olsson, Göran; Edberg, Terry; Belyayev, Serhiy; Marusenkov, Andriy

2008-01-01

A novel design of an Earth field digital fluxgate magnetometer is presented, the small magnetometer in low-mass experiment (SMILE). The combination of a number of new techniques results in significant miniaturization of both sensor and electronics. The design uses a sensor with volume compensation, combining three dual rod cores in a Macor® cube with the side dimension of 20 mm. Use of volume compensation provides high geometrical stability of the axes and improved performance compared to component compensated sensors. The sensor is operated at an excitation frequency of 8 kHz. Most of the instrument functionality is combined in a digital signal processing core, implemented in a field programmable gate array (FPGA). The pick-up signal is digitized after amplification and filtering, and values of compensation currents for each of the axes are determined by a digital correlation algorithm, equivalent to a matched filter, and are fed to a hybrid pulse-width modulation/delta-sigma digital-to-analogue converter driving the currents through the compensation coils. Using digital design makes the instrument very flexible, reduces power consumption and opens possibilities for the customization of the operation modes. The current implementation of the design is based on commercial off-the-shelf components. A calibration of the SMILE instrument was carried out at the Nurmijärvi Geophysical Observatory, showing high linearity (within 6 nT on the whole ±50 µT scale), good orthogonality (22 arcmin) and very good temperature stability of the axes

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.

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

International Nuclear Information System (INIS)

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

2002-01-01

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

A Survey On Mean Glandular Dose From Full-Field Digital Mammography Systems, Operate Using Mo/ Mo And W/Rh Target/ Filter Combinations

International Nuclear Information System (INIS)

Noriah Jamal; Siti Selina Abdul Hamid; Humairah Samad Cheung; Siti Kamariah Che Mohamed; Ellyda Muhammed Nordin; Radhiana Hassan; Rehir Dahalan

2013-01-01

We had conducted a survey on Mean Glandular Dose (MGD) from Full-Field Digital Mammography systems (FFDM) operate using Molybdenum/ Molybdenum (Mo/ Mo) and Tungsten/ Rhodium (W/ Rh) target/ filter combinations. A survey was carried out at two randomly selected mammography centres in Malaysia, namely National Cancer Society and International Islamic University of Malaysia. The first centre operates using a W/ Rh, while the second centre operates using an Mo/ Mo target/ filter combinations. On the basis of recorded information, data on mammographic views, MGD, age and Compressed Breast Thickness (CBT) were recorded for 100 patients, for each mammographic centre respectively. The MGD data were analyzed for variation with age group, with 5 years increment. The MGD data were also analyzed for variation with CBT, with 5 mm increment. We found that for both CC and MLO views, FFDM systems operated using Mo/ Mo and W/ Rh target/ filter combinations present the same trend on MGD. The average MGD decreases as age increases. While average MGD increases with the increasing of CBT. However, FFDM system operates using Mo/ Mo gives higher MGD as compared with FFDM system operates using W/ Rh. (author)

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.

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

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)

Small fields measurements with radiochromic films.

Science.gov (United States)

Gonzalez-Lopez, Antonio; Vera-Sanchez, Juan-Antonio; Lago-Martin, Jose-Domingo

2015-01-01

The small fields in radiotherapy are widely used due to the development of techniques such as intensity-modulated radiotherapy and stereotactic radio surgery. The measurement of the dose distributions for small fields is a challenge. A perfect dosimeter should be independent of the radiation energy and the dose rate and should have a negligible volume effect. The radiochromic (RC) film characteristics fit well to these requirements. However, the response of RC films and their digitizing processes present a significant spatial inhomogeneity problem. The present work uses a method for two-dimensional (2D) measurement with RC films based on the reduction of the spatial inhomogeneity of both the film and the film digitizing process. By means of registering and averaging several measurements of the same field, the inhomogeneities are mostly canceled. Measurements of output factors (OFs), dose profiles (in-plane and cross-plane), and 2D dose distributions are presented. The field sizes investigated are 0.5 × 0.5 cm(2), 0.7 × 0.7 cm(2), 1 × 1 cm(2), 2 × 2 cm(2), 3 × 3 cm(2), 6 × 6 cm(2), and 10 × 10 cm(2) for 6 and 15 MV photon beams. The OFs measured with the RC film are compared with the measurements carried out with a PinPoint ionization chamber (IC) and a Semiflex IC, while the measured transversal dose profiles were compared with Monte Carlo simulations. The results obtained for the OFs measurements show a good agreement with the values obtained from RC films and the PinPoint and Semiflex chambers when the field size is greater or equal than 2 × 2 cm(2). These agreements give confidence on the accuracy of the method as well as on the results obtained for smaller fields. Also, good agreement was found between the measured profiles and the Monte Carlo calculated profiles for the field size of 1 × 1 cm(2). We expect, therefore, that the presented method can be used to perform accurate measurements of small fields.

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

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.

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.)

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...

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.

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

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.

Deep learning in breast cancer risk assessment: evaluation of convolutional neural networks on a clinical dataset of full-field digital mammograms.

Science.gov (United States)

Li, Hui; Giger, Maryellen L; Huynh, Benjamin Q; Antropova, Natalia O

2017-10-01

To evaluate deep learning in the assessment of breast cancer risk in which convolutional neural networks (CNNs) with transfer learning are used to extract parenchymal characteristics directly from full-field digital mammographic (FFDM) images instead of using computerized radiographic texture analysis (RTA), 456 clinical FFDM cases were included: a "high-risk" BRCA1/2 gene-mutation carriers dataset (53 cases), a "high-risk" unilateral cancer patients dataset (75 cases), and a "low-risk dataset" (328 cases). Deep learning was compared to the use of features from RTA, as well as to a combination of both in the task of distinguishing between high- and low-risk subjects. Similar classification performances were obtained using CNN [area under the curve [Formula: see text]; standard error [Formula: see text

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.)

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.

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.

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.

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.

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.

The Place of Digital Marketing on Turkish Small Businesses

Directory of Open Access Journals (Sweden)

Serhat Karatum

2017-12-01

Full Text Available In the 21st century, technology develops rapidly and continuously and it affects every aspect of our lives. Marketing concept has been affected by these developments. What we want from marketing and reaching in an increasingly virtualized world is to be a lot faster than the past. Also, new marketing channels have emerged as well. Turkish small businesses, the building blocks of Turkish economy, have the chance of addressing the marketing problems and solving the problems with the digital marketing channels. Small businesses have time and cash money limitations and this restricts their development. It is aimed to inform Turkish small businesses about Turkish population’s digital channel usage and the benefits of using digital marketing channels. As a result, digital marketing is going to improve the speed of renewal process of the Turkish small businesses and competition between them will improve the economy of Turkey. In the 21st century, technology develops rapidly and continuously and it affects every aspect of our lives. Marketing concept has been affected by these developments. What we want from marketing and reaching in an increasingly virtualized world is to be a lot faster than the past. Also, new marketing channels have emerged as well. Turkish small businesses, the building blocks of Turkish economy, have the chance of addressing the marketing problems and solving the problems with the digital marketing channels. Small businesses have time and cash money limitations and this restricts their development. It is aimed to inform Turkish small businesses about Turkish population’s digital channel usage and the benefits of using digital marketing channels. As a result, digital marketing is going to improve the speed of renewal process of the Turkish small businesses and competition between them will improve the economy of Turkey.

[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.

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...

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

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

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.

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.

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

Comparing the visualization of microcalcifications with direct magnification in digital full-field mammography vs. film-screen mammography

International Nuclear Information System (INIS)

Diekmann, F.; Diekmann, S.; Rogalla, P.; Hamm, B.; Bick, U.; Blohmer, J.U.; Winzer, K.J.

2002-01-01

Purpose: To evaluate the conspicuity of microcalcifications in magnified mammographic views of preparations obtained with full field digital mammography (FFDM), film-screen mammography (FSM), and the DIMA technique. Material and Methods: Twelve preparations were examined by FFDM and FSM using 1.8 x magnification and DIMA using 7 x magnification. Parameter settings were identical for all three techniques. The number of visible microcalcifications was then determined for each modality by three radiologists. As far as possible, all preparations were X-rayed at 22 kV and 10 mAS. Results: Altogether 9705 calcifications were counted (DIMA: 1609/1542/1534; FFDM: 1020/753/881; FSM: 901/643/822). The total number of microcalcifications identified with the DIMA technique was 4685 as compared to 2654 with FFDM and 2366 with FSM. The calcifications counted with FFDM and FSM thus corresponded to 56.6% and 50.5%, respectively, of those identified with DIMA. The differences between the groups were statistically significant (F-Test, p [de

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

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.)

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)

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

International Nuclear Information System (INIS)

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

2012-01-01

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

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.

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.

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

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

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

International Nuclear Information System (INIS)

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

2006-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2006-04-15

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

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.

Digital archaeology field recording in the 4th dimension: ArchField C++ a 4D GIS for digital field work

KAUST Repository

Smith, Neil; Howland, Matthew; Levy, Thomas E.

2016-01-01

With the rapid adoption of laser scanning and photogrammetry among the archaeological community the creation of point cloud `data scaffolds' and digital documentation of archaeological sites is now becoming common. In field excavations, however, the continual exposure of archaeological layers requires a digital toolset in which to record, categorize and spatially locate artifacts, installations, and loci within a site's daily 3D or aerial scan. We present ArchField C++, the latest version of our digital field recording software that enables real-time digital GIS 3D Top Plan production within a rendering engine designed for visualizing massive 3D datasets. ArchField directly connects to Total Stations and our RTK GPS units to record sub-centimeter measurements for artifacts, scanning markers, loci boundaries, and camera positions. The processing pipeline enables the generation of publishable orthographic and perspective maps from the first day of excavation to the last. As a backend it uses a PostGIS database and the ability to export and import various vector, raster, DEM and 3D datasets that can be hosted by on-line geo-referenced databases. We present the application of ArchField C++ to our 2014 field excavations of the early Iron Age site of Khirbat al-Jariyah located in Southern Jordan.

Digital archaeology field recording in the 4th dimension: ArchField C++ a 4D GIS for digital field work

KAUST Repository

Smith, Neil

2016-02-25

With the rapid adoption of laser scanning and photogrammetry among the archaeological community the creation of point cloud `data scaffolds\\' and digital documentation of archaeological sites is now becoming common. In field excavations, however, the continual exposure of archaeological layers requires a digital toolset in which to record, categorize and spatially locate artifacts, installations, and loci within a site\\'s daily 3D or aerial scan. We present ArchField C++, the latest version of our digital field recording software that enables real-time digital GIS 3D Top Plan production within a rendering engine designed for visualizing massive 3D datasets. ArchField directly connects to Total Stations and our RTK GPS units to record sub-centimeter measurements for artifacts, scanning markers, loci boundaries, and camera positions. The processing pipeline enables the generation of publishable orthographic and perspective maps from the first day of excavation to the last. As a backend it uses a PostGIS database and the ability to export and import various vector, raster, DEM and 3D datasets that can be hosted by on-line geo-referenced databases. We present the application of ArchField C++ to our 2014 field excavations of the early Iron Age site of Khirbat al-Jariyah located in Southern Jordan.

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)

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.

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.

False Negative Mammogram of Breast Cancer : Analysis of Mammographic and Sonographic Findings and Correlation with Clinical Findings

International Nuclear Information System (INIS)

Lee, Kil Jun; Lee, Ji Yeon; Han, Sung Nim; Jeong, Seong Ki; Tae, Seok; Shin, Kyoung Ja; Lee, Sang Chun

1995-01-01

Recent mammographic equipment have been of good quality and yielded high diagnostic accuracy for the detection of breast cancer. However, negative mammogram does not necessarily rule out breast cancer. Therefore were viewed cause of false negative mammography in confirmed breast cancer to improve diagnostic accuracy and for adequate clinical approach. We reviewed 19 cases of confirmed breast cancer, which showed false negative mammography with positive sonographic findings. Retrospective analysis was done by correlating the patient's age, sonographic finding and mass size, mammographic breast pattern and cause of false negative mammogram, and clinical symptoms. Among the 5 patients below 35 years in age, mass was not visible due to dense breast in 4 and due to small size in 1 case. In 14 patients over 35 years in age, 11 had normal mammographic findings, 4 had dense breast, and 7 had small sized mass. Remaining 3 cases showed asymmetric density in 2 and architecture distortion in 1 case. All showed mass lesion in sonography : ill defined malignant appearance in 14,well defined malignant appearance in 2, and well defined benign in 3 cases. Negative mammogram should be correlated with sonography in case of dense breast, below 35 years in age with palpable mass and under risk for breast cancer

A field guide to digital color

CERN Document Server

Stone, Maureen

2013-01-01

Maureen Stone's field guide to digital color presents a survey of digital color with special emphasis on those fields important for computer graphics. The book provides the foundation for understanding color and its applications, discusses color media and color management and the use of color in computer graphics, including color design and selection. The book provides a guide for anyone who wants to understand and apply digital color. An annotated bibliography provides in-depth references for further study on each topic.

Preliminary Clinical Experience with a Combined Automated Breast Ultrasound and Digital Breast Tomosynthesis System.

Science.gov (United States)

Larson, Eric D; Lee, Won-Mean; Roubidoux, Marilyn A; Goodsitt, Mitchell M; Lashbrook, Chris; Davis, Cynthia E; Kripfgans, Oliver D; Carson, Paul L

2018-03-01

We analyzed the performance of a mammographically configured, automated breast ultrasound (McABUS) scanner combined with a digital breast tomosynthesis (DBT) system. The GE Invenia ultrasound system was modified for integration with GE DBT systems. Ultrasound and DBT imaging were performed in the same mammographic compression. Our small preliminary study included 13 cases, six of whom had contained invasive cancers. From analysis of these cases, current limitations and corresponding potential improvements of the system were determined. A registration analysis was performed to compare the ease of McABUS to DBT registration for this system with that of two systems designed previously. It was observed that in comparison to data from an earlier study, the McABUS-to-DBT registration alignment errors for both this system and a previously built combined system were smaller than those for a previously built standalone McABUS system. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

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

Investigation on location-dependent detectability of a small mass for digital breast tomosynthesis evaluation

Science.gov (United States)

Lee, Changwoo; Baek, Jongduk; Park, Subok

2016-03-01

Digital breast tomosynthesis (DBT) is an emerging imaging modality for improved breast cancer detection and diagnosis [1-5]. Numerous efforts have been made to find quantitative metrics associated with mammographic image quality assessment, such as the exponent β of anatomical noise power spectrum, glandularity, contrast noise ratio, etc. [6-8]. In addition, with the use of Fourier-domain detectability for a task-based assessment of DBT, a stationarity assumption on reconstructed image statistics was often made [9-11], resulting in the use of multiple regions-of-interest (ROIs) from different locations in order to increase sample size. While all these metrics provide some information on mammographic image characteristics and signal detection, the relationship between these metrics and detectability in DBT evaluation has not been fully understood. In this work, we investigated spatial-domain detectability trends and levels as a function of the number of slices Ns at three different ROI locations on the same image slice, where background statistics differ in terms of the aforementioned metrics. Detectabilities for the three ROI locations were calculated using multi-slice channelized Hotelling observers with 2D/3D Laguerre-Gauss channels. Our simulation results show that detectability levels and trends as a function of Ns vary across these three ROI locations. They also show that the exponent β, mean glandularity, and mean attenuation coefficient vary across the three ROI locations but they do not necessarily predict the ranking of detectability levels and trends across these ROI locations.

Digital tripwire: a small automated human detection system

Science.gov (United States)

Fischer, Amber D.; Redd, Emmett; Younger, A. Steven

2009-05-01

A low cost, lightweight, easily deployable imaging sensor that can dependably discriminate threats from other activities within its field of view and, only then, alert the distant duty officer by transmitting a visual confirmation of the threat would provide a valuable asset to modern defense. At present, current solutions suffer from a multitude of deficiencies - size, cost, power endurance, but most notably, an inability to assess an image and conclude that it contains a threat. The human attention span cannot maintain critical surveillance over banks of displays constantly conveying such images from the field. DigitalTripwire is a small, self-contained, automated human-detection system capable of running for 1-5 days on two AA batteries. To achieve such long endurance, the DigitalTripwire system utilizes an FPGA designed with sleep functionality. The system uses robust vision algorithms, such as a partially unsupervised innovative backgroundmodeling algorithm, which employ several data reduction strategies to operate in real-time, and achieve high detection rates. When it detects human activity, either mounted or dismounted, it sends an alert including images to notify the command center. In this paper, we describe the hardware and software design of the DigitalTripwire system. In addition, we provide detection and false alarm rates across several challenging data sets demonstrating the performance of the vision algorithms in autonomously analyzing the video stream and classifying moving objects into four primary categories - dismounted human, vehicle, non-human, or unknown. Performance results across several challenging data sets are provided.

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

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

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

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...

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

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.

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

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.

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.

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 ...

Small Organisations and Cultural Institutions--A Digital Future?

Science.gov (United States)

Spence, Jaqueline

2005-01-01

Purpose: This paper aims to examine how technology presents both problems and opportunities for the historian, the researcher, small organisations, and cultural heritage institutions. Ways of safeguarding historical material in digital form are suggested, and the role of cultural heritage bodies as managers of sustainable digital collections is…

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)

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

Small Field of View Scintimammography Gamma Camera Integrated to a Stereotactic Core Biopsy Digital X-ray System

Energy Technology Data Exchange (ETDEWEB)

Andrew Weisenberger; Fernando Barbosa; T. D. Green; R. Hoefer; Cynthia Keppel; Brian Kross; Stanislaw Majewski; Vladimir Popov; Randolph Wojcik

2002-10-01

A small field of view gamma camera has been developed for integration with a commercial stereotactic core biopsy system. The goal is to develop and implement a dual-modality imaging system utilizing scintimammography and digital radiography to evaluate the reliability of scintimammography in predicting the malignancy of suspected breast lesions from conventional X-ray mammography. The scintimammography gamma camera is a custom-built mini gamma camera with an active area of 5.3 cm /spl times/ 5.3 cm and is based on a 2 /spl times/ 2 array of Hamamatsu R7600-C8 position-sensitive photomultiplier tubes. The spatial resolution of the gamma camera at the collimator surface is < 4 mm full-width at half-maximum and a sensitivity of /spl sim/ 4000 Hz/mCi. The system is also capable of acquiring dynamic scintimammographic data to allow for dynamic uptake studies. Sample images of preliminary clinical results are presented to demonstrate the performance of the system.

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

Real-time visualization and analysis of airflow field by use of digital holography

Science.gov (United States)

Di, Jianglei; Wu, Bingjing; Chen, Xin; Liu, Junjiang; Wang, Jun; Zhao, Jianlin

2013-04-01

The measurement and analysis of airflow field is very important in fluid dynamics. For airflow, smoke particles can be added to visually observe the turbulence phenomena by particle tracking technology, but the effect of smoke particles to follow the high speed airflow will reduce the measurement accuracy. In recent years, with the advantage of non-contact, nondestructive, fast and full-field measurement, digital holography has been widely applied in many fields, such as deformation and vibration analysis, particle characterization, refractive index measurement, and so on. In this paper, we present a method to measure the airflow field by use of digital holography. A small wind tunnel model made of acrylic glass is built to control the velocity and direction of airflow. Different shapes of samples such as aircraft wing and cylinder are placed in the wind tunnel model to produce different forms of flow field. With a Mach-Zehnder interferometer setup, a series of digital holograms carrying the information of airflow filed distributions in different states are recorded by CCD camera and corresponding holographic images are numerically reconstructed from the holograms by computer. Then we can conveniently obtain the velocity or pressure information of the airflow deduced from the quantitative phase information of holographic images and visually display the airflow filed and its evolution in the form of a movie. The theory and experiment results show that digital holography is a robust and feasible approach for real-time visualization and analysis of airflow field.

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....

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)

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

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)

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....

Digital portal radiography in mantle-field irradiation

International Nuclear Information System (INIS)

Scheck, R.J.; Wendt, T.; Panzer, M.

1991-01-01

This paper evaluates the potential of digital luminescence radiography to improve image quality of portal films in mantle-field irradiation. Conventional and digital verification films of an anthropomorphic phantom and 20 patients treated for Hodgkin disease with mantle radiation therapy were obtained with high-energy photon beams. Both conventional films and storage phosphor screens were placed into a cassette with steel intensifier screens. Exposed storage phosphor screens were processed in a semiautomatic mode, with an optimized contrast curve with moderate edge enhancement, and printed as hard copies in a double-image output format. Images were evaluated according to contrast resolution, delineation of anatomic structures, and accuracy of field alignment. Digital portal radiographs were superior to conventional ones with regard to contrast resolution. Thus, they allowed quick and easy detection of relevant structures, although delineation of anatomic structures and field alignments were judged to be equivalent with both techniques. Shorter exposure times for digital images resulted in a reduction in motion artifacts

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

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

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

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

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

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

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

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

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.

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)

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)

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

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

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

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.

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.

Design and testing of a 750 MHz CW-EPR digital console for small animal imaging

Science.gov (United States)

Sato-Akaba, Hideo; Emoto, Miho C.; Hirata, Hiroshi; Fujii, Hirotada G.

2017-11-01

This paper describes the development of a digital console for three-dimensional (3D) continuous wave electron paramagnetic resonance (CW-EPR) imaging of a small animal to improve the signal-to-noise ratio and lower the cost of the EPR imaging system. A RF generation board, an RF acquisition board and a digital signal processing (DSP) & control board were built for the digital EPR detection. Direct sampling of the reflected RF signal from a resonator (approximately 750 MHz), which contains the EPR signal, was carried out using a band-pass subsampling method. A direct automatic control system to reduce the reflection from the resonator was proposed and implemented in the digital EPR detection scheme. All DSP tasks were carried out in field programmable gate array ICs. In vivo 3D imaging of nitroxyl radicals in a mouse's head was successfully performed.

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.

Quantitative Assessment of Mammary Gland Density in Rodents Using Digital Image Analysis

Directory of Open Access Journals (Sweden)

Thompson Henry J

2011-06-01

Full Text Available Abstract Background Rodent models have been used extensively to study mammary gland development and for studies of toxicology and carcinogenesis. Mammary gland gross morphology can visualized via the excision of intact mammary gland chains following fixation and staining with carmine using a tissue preparation referred to as a whole mount. Methods are described for the automated collection of digital images from an entire mammary gland whole mount and for the interrogation of digital data using a "masking" technique available with Image-Pro® plus image analysis software (Mediacybernetics. Silver Spring, MD. Results Parallel to mammographic analysis in humans, measurements of rodent mammary gland density were derived from area-based or volume-based algorithms and included: total circumscribed mammary fat pad mass, mammary epithelial mass, and epithelium-free fat pad mass. These values permitted estimation of absolute mass of mammary epithelium as well as breast density. The biological plausibility of these measurements was evaluated in mammary whole mounts from rats and mice. During mammary gland development, absolute epithelial mass increased linearly without significant changes in mammographic density. Treatment of rodents with tamoxifen, 9-cis-retinoic acid, or ovariectomy, and occurrence of diet induced obesity decreased both absolute epithelial mass and mammographic density. The area and volumetric methods gave similar results. Conclusions Digital image analysis can be used for screening agents for potential impact on reproductive toxicity or carcinogenesis as well as for mechanistic studies, particularly for cumulative effects on mammary epithelial mass as well as translational studies of mechanisms that explain the relationship between epithelial mass and cancer risk.

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)

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.

Iso-precision scaling of digitized mammograms to facilitate image analysis

International Nuclear Information System (INIS)

Karssmeijer, N.; van Erning, L.

1991-01-01

This paper reports on a 12 bit CCD camera equipped with a linear sensor of 4096 photodiodes which is used to digitize conventional mammographic films. An iso-precision conversion of the pixel values is preformed to transform the image data to a scale on which the image noise is equal at each level. For this purpose film noise and digitization noise have been determined as a function of optical density and pixel size. It appears that only at high optical densities digitization noise is comparable to or larger than film noise. The quantization error caused by compression of images recorded with 12 bits per pixel to 8 bit images by an iso-precision conversion has been calculated as a function of the number of quantization levels. For mammograms digitized in a 4096 2 matrix the additional error caused by such a scale transform is only about 1.5 percent. An iso-precision scale transform can be advantageous when automated procedures for quantitative image analysis are developed. Especially when detection of signals in noise is aimed at, a constant noise level over the whole pixel value range is very convenient. This is demonstrated by applying local thresholding to detect small microcalcifications. Results are compared to those obtained by using logarithmic or linearized scales

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.

Design and testing of a 750MHz CW-EPR digital console for small animal imaging.

Science.gov (United States)

Sato-Akaba, Hideo; Emoto, Miho C; Hirata, Hiroshi; Fujii, Hirotada G

2017-11-01

This paper describes the development of a digital console for three-dimensional (3D) continuous wave electron paramagnetic resonance (CW-EPR) imaging of a small animal to improve the signal-to-noise ratio and lower the cost of the EPR imaging system. A RF generation board, an RF acquisition board and a digital signal processing (DSP) & control board were built for the digital EPR detection. Direct sampling of the reflected RF signal from a resonator (approximately 750MHz), which contains the EPR signal, was carried out using a band-pass subsampling method. A direct automatic control system to reduce the reflection from the resonator was proposed and implemented in the digital EPR detection scheme. All DSP tasks were carried out in field programmable gate array ICs. In vivo 3D imaging of nitroxyl radicals in a mouse's head was successfully performed. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

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....

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.

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.

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

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.

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

The impact of digital imaging in the field of cytopathology.

Science.gov (United States)

Pantanowitz, Liron; Hornish, Maryanne; Goulart, Robert A

2009-03-06

With the introduction of digital imaging, pathology is undergoing a digital transformation. In the field of cytology, digital images are being used for telecytology, automated screening of Pap test slides, training and education (e.g. online digital atlases), and proficiency testing. To date, there has been no systematic review on the impact of digital imaging on the practice of cytopathology. This article critically addresses the emerging role of computer-assisted screening and the application of digital imaging to the field of cytology, including telecytology, virtual microscopy, and the impact of online cytology resources. The role of novel diagnostic techniques like image cytometry is also reviewed.

Dose and risk evaluation in digital mammography using computer modeling

Energy Technology Data Exchange (ETDEWEB)

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

2010-07-01

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

Dose and risk evaluation in digital mammography using computer modeling

International Nuclear Information System (INIS)

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

2010-01-01

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

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)

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.

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.

Automatic Estimation of Volumetric Breast Density Using Artificial Neural Network-Based Calibration of Full-Field Digital Mammography: Feasibility on Japanese Women With and Without Breast Cancer.

Science.gov (United States)

Wang, Jeff; Kato, Fumi; Yamashita, Hiroko; Baba, Motoi; Cui, Yi; Li, Ruijiang; Oyama-Manabe, Noriko; Shirato, Hiroki

2017-04-01

Breast cancer is the most common invasive cancer among women and its incidence is increasing. Risk assessment is valuable and recent methods are incorporating novel biomarkers such as mammographic density. Artificial neural networks (ANN) are adaptive algorithms capable of performing pattern-to-pattern learning and are well suited for medical applications. They are potentially useful for calibrating full-field digital mammography (FFDM) for quantitative analysis. This study uses ANN modeling to estimate volumetric breast density (VBD) from FFDM on Japanese women with and without breast cancer. ANN calibration of VBD was performed using phantom data for one FFDM system. Mammograms of 46 Japanese women diagnosed with invasive carcinoma and 53 with negative findings were analyzed using ANN models learned. ANN-estimated VBD was validated against phantom data, compared intra-patient, with qualitative composition scoring, with MRI VBD, and inter-patient with classical risk factors of breast cancer as well as cancer status. Phantom validations reached an R 2 of 0.993. Intra-patient validations ranged from R 2 of 0.789 with VBD to 0.908 with breast volume. ANN VBD agreed well with BI-RADS scoring and MRI VBD with R 2 ranging from 0.665 with VBD to 0.852 with breast volume. VBD was significantly higher in women with cancer. Associations with age, BMI, menopause, and cancer status previously reported were also confirmed. ANN modeling appears to produce reasonable measures of mammographic density validated with phantoms, with existing measures of breast density, and with classical biomarkers of breast cancer. FFDM VBD is significantly higher in Japanese women with cancer.

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.

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.

Description and benefits of dynamic collimation in digital breast tomosynthesis

International Nuclear Information System (INIS)

Popova, Y.; Hersemeule, G.; Klausz, R.; Souchay, H.

2015-01-01

X-ray field to image receptor active area alignment is usually tested in mammographic QC. In digital breast tomosynthesis (dBT), the source moves during the acquisition, generating a displacement of the X-ray beam edges relative to the detector, in or out of the detector active area. To minimise unnecessary radiation while maximising the useful field of view, a solution consisting in adjusting the collimation with the source rotation was implemented on the GE SenoClaire dBT system. This solution is described and tested using three different methods based on: (1) images from the detector, (2) a non-screen film and (3) a semiconductor tool providing the X-ray intensity profile. Method 1 demonstrated a maximum positioning error of 0.3 mm. Method 2 was found non-applicable; Method 3 provided measurements within 1.5 mm. Dynamic collimation enables maintaining an X-ray field to detector congruence comparable with 2D. Measuring the position of the X-ray field edges using a dedicated tool makes routine QC possible. (authors)

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

Digital maintenance field technology for the maintenance of nuclear power plant

International Nuclear Information System (INIS)

Sato, Tomomasa; Asama, Hajime; Kita, Nobuyuki; Numano, Masayoshi

2002-01-01

This paper proposes a concept of 'Digital Maintenance Field Technology', which enables human beings and working robots making fully use of the necessary information for maintenance activity not only in any location of the maintenance field (seamless in location) but also in any moment from the past to the future (seamless in time) and in any format in presenting to human (seamless in semantics). The paper points out the following three essential components of the technology: 1) 'Digital Field Construction Technology', 2) 'Digital Field Archival Technology' and 3) 'Digital Field Presentation Technology'. The necessary capabilities are extracted and our approaches and state of the art of realizing these capabilities are introduced in addition to present the state of the art of home application example. The future extension is also illustrated. (author)

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

Hough transform for clustered microcalcifications detection in full-field digital mammograms

Science.gov (United States)

Fanizzi, A.; Basile, T. M. A.; Losurdo, L.; Amoroso, N.; Bellotti, R.; Bottigli, U.; Dentamaro, R.; Didonna, V.; Fausto, A.; Massafra, R.; Moschetta, M.; Tamborra, P.; Tangaro, S.; La Forgia, D.

2017-09-01

Many screening programs use mammography as principal diagnostic tool for detecting breast cancer at a very early stage. Despite the efficacy of the mammograms in highlighting breast diseases, the detection of some lesions is still doubtless for radiologists. In particular, the extremely minute and elongated salt-like particles of microcalcifications are sometimes no larger than 0.1 mm and represent approximately half of all cancer detected by means of mammograms. Hence the need for automatic tools able to support radiologists in their work. Here, we propose a computer assisted diagnostic tool to support radiologists in identifying microcalcifications in full (native) digital mammographic images. The proposed CAD system consists of a pre-processing step, that improves contrast and reduces noise by applying Sobel edge detection algorithm and Gaussian filter, followed by a microcalcification detection step performed by exploiting the circular Hough transform. The procedure performance was tested on 200 images coming from the Breast Cancer Digital Repository (BCDR), a publicly available database. The automatically detected clusters of microcalcifications were evaluated by skilled radiologists which asses the validity of the correctly identified regions of interest as well as the system error in case of missed clustered microcalcifications. The system performance was evaluated in terms of Sensitivity and False Positives per images (FPi) rate resulting comparable to the state-of-art approaches. The proposed model was able to accurately predict the microcalcification clusters obtaining performances (sensibility = 91.78% and FPi rate = 3.99) which favorably compare to other state-of-the-art approaches.

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

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)

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

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

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

Evaluation of using digital gravity field models for zoning map creation

Science.gov (United States)

Loginov, Dmitry

2018-05-01

At the present time the digital cartographic models of geophysical fields are taking a special significance into geo-physical mapping. One of the important directions to their application is the creation of zoning maps, which allow taking into account the morphology of geophysical field in the implementation automated choice of contour intervals. The purpose of this work is the comparative evaluation of various digital models in the creation of integrated gravity field zoning map. For comparison were chosen the digital model of gravity field of Russia, created by the analog map with scale of 1 : 2 500 000, and the open global model of gravity field of the Earth - WGM2012. As a result of experimental works the four integrated gravity field zoning maps were obtained with using raw and processed data on each gravity field model. The study demonstrates the possibility of open data use to create integrated zoning maps with the condition to eliminate noise component of model by processing in specialized software systems. In this case, for solving problem of contour intervals automated choice the open digital models aren't inferior to regional models of gravity field, created for individual countries. This fact allows asserting about universality and independence of integrated zoning maps creation regardless of detail of a digital cartographic model of geo-physical fields.

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.

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.

Digital reporting by small private companies in the UK

OpenAIRE

Alkhatib, Esraa

2016-01-01

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London. Abstract This thesis investigates the factors that affect the take-up of statutory digital reporting of statutory accounts and returns to the tax authority (HM Revenue and Customs) and voluntary digital reporting to the company registry (Companies House) by small private companies in the UK. In doing so, it identifies the costs and benefits of this innovation from the perspective...

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

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.

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

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 ...

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

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.

A three-frame digital image correlation (DIC) method for the measurement of small displacements and strains

International Nuclear Information System (INIS)

Cofaru, C; Philips, W; Van Paepegem, W

2012-01-01

Digital image correlation (DIC) has become a well-established approach for the calculation of full-field displacement and strains within the field of experimental mechanics. Since their introduction, DIC methods have been relying on only two images to measure the displacements and strains that materials undergo under load. It can be foreseen that the use of additional image information for the calculus of displacements and strains, although computationally more expensive, can positively impact DIC method accuracy under both ideal and challenging experimental conditions. Such accuracy improvements are especially important when measuring very small deformations, which still constitutes a great challenge: small displacements and strains translate into equally small digital image intensity changes on the material’s surface, which are affected by the digitization processes of the imaging hardware and by other image acquisition effects such as image noise. This paper proposes a new three-frame Newton–Raphson DIC method and evaluates it from the standpoints of accuracy and speed. The method models the deformations that are to be measured under the assumption that the deformation occurs at approximately the same rate between each two consecutive images in the three image sequences that are employed. The aim is to investigate how the use of image data from more than two images impacts accuracy and what is the effect on the computational speed. The proposed method is compared with the classic two-frame Newton–Raphson method in three experiments. Two experiments rely on numerically deformed images that simulate heterogeneous deformations. The third experiment uses images from a real deformation experiment. Results indicate that although it is computationally more demanding, the three-frame method significantly improves displacement and strain accuracy and is less sensitive to image noise. (paper)

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.

Dual-energy digital mammography for calcification imaging: Scatter and nonuniformity corrections

International Nuclear Information System (INIS)

Kappadath, S. Cheenu; Shaw, Chris C.

2005-01-01

Mammographic images of small calcifications, which are often the earliest signs of breast cancer, can be obscured by overlapping fibroglandular tissue. We have developed and implemented a dual-energy digital mammography (DEDM) technique for calcification imaging under full-field imaging conditions using a commercially available aSi:H/CsI:Tl flat-panel based digital mammography system. The low- and high-energy images were combined using a nonlinear mapping function to cancel the tissue structures and generate the dual-energy (DE) calcification images. The total entrance-skin exposure and mean-glandular dose from the low- and high-energy images were constrained so that they were similar to screening-examination levels. To evaluate the DE calcification image, we designed a phantom using calcium carbonate crystals to simulate calcifications of various sizes (212-425 μm) overlaid with breast-tissue-equivalent material 5 cm thick with a continuously varying glandular-tissue ratio from 0% to 100%. We report on the effects of scatter radiation and nonuniformity in x-ray intensity and detector response on the DE calcification images. The nonuniformity was corrected by normalizing the low- and high-energy images with full-field reference images. Correction of scatter in the low- and high-energy images significantly reduced the background signal in the DE calcification image. Under the current implementation of DEDM, utilizing the mammography system and dose level tested, calcifications in the 300-355 μm size range were clearly visible in DE calcification images. Calcification threshold sizes decreased to the 250-280 μm size range when the visibility criteria were lowered to barely visible. Calcifications smaller than ∼250 μm were usually not visible in most cases. The visibility of calcifications with our DEDM imaging technique was limited by quantum noise, not system noise

A novel deep learning-based approach to high accuracy breast density estimation in digital mammography

Science.gov (United States)

Ahn, Chul Kyun; Heo, Changyong; Jin, Heongmin; Kim, Jong Hyo

2017-03-01

Mammographic breast density is a well-established marker for breast cancer risk. However, accurate measurement of dense tissue is a difficult task due to faint contrast and significant variations in background fatty tissue. This study presents a novel method for automated mammographic density estimation based on Convolutional Neural Network (CNN). A total of 397 full-field digital mammograms were selected from Seoul National University Hospital. Among them, 297 mammograms were randomly selected as a training set and the rest 100 mammograms were used for a test set. We designed a CNN architecture suitable to learn the imaging characteristic from a multitudes of sub-images and classify them into dense and fatty tissues. To train the CNN, not only local statistics but also global statistics extracted from an image set were used. The image set was composed of original mammogram and eigen-image which was able to capture the X-ray characteristics in despite of the fact that CNN is well known to effectively extract features on original image. The 100 test images which was not used in training the CNN was used to validate the performance. The correlation coefficient between the breast estimates by the CNN and those by the expert's manual measurement was 0.96. Our study demonstrated the feasibility of incorporating the deep learning technology into radiology practice, especially for breast density estimation. The proposed method has a potential to be used as an automated and quantitative assessment tool for mammographic breast density in routine practice.

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.

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

Field-Deployable Acoustic Digital Systems for Noise Measurement

Science.gov (United States)

Shams, Qamar A.; Wright, Kenneth D.; Lunsford, Charles B.; Smith, Charlie D.

2000-01-01

Langley Research Center (LaRC) has for years been a leader in field acoustic array measurement technique. Two field-deployable digital measurement systems have been developed to support acoustic research programs at LaRC. For several years, LaRC has used the Digital Acoustic Measurement System (DAMS) for measuring the acoustic noise levels from rotorcraft and tiltrotor aircraft. Recently, a second system called Remote Acquisition and Storage System (RASS) was developed and deployed for the first time in the field along with DAMS system for the Community Noise Flight Test using the NASA LaRC-757 aircraft during April, 2000. The test was performed at Airborne Airport in Wilmington, OH to validate predicted noise reduction benefits from alternative operational procedures. The test matrix was composed of various combinations of altitude, cutback power, and aircraft weight. The DAMS digitizes the acoustic inputs at the microphone site and can be located up to 2000 feet from the van which houses the acquisition, storage and analysis equipment. Digitized data from up to 10 microphones is recorded on a Jaz disk and is analyzed post-test by microcomputer system. The RASS digitizes and stores acoustic inputs at the microphone site that can be located up to three miles from the base station and can compose a 3 mile by 3 mile array of microphones. 16-bit digitized data from the microphones is stored on removable Jaz disk and is transferred through a high speed array to a very large high speed permanent storage device. Up to 30 microphones can be utilized in the array. System control and monitoring is accomplished via Radio Frequency (RF) link. This paper will present a detailed description of both systems, along with acoustic data analysis from both systems.

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.)

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.)

Small format digital photogrammetry for applications in the earth sciences

Science.gov (United States)

Rieke-Zapp, Dirk

2010-05-01

Small format digital photogrammetry for applications in the earth sciences Photogrammetry is often considered one of the most precise and versatile surveying techniques. The same camera and analysis software can be used for measurements from sub-millimetre to kilometre scale. Such a measurement device is well suited for application by earth scientists working in the field. In this case a small toolset and a straight forward setup best fit the needs of the operator. While a digital camera is typically already part of the field equipment of an earth scientist the main focus of the field work is often not surveying. Lack in photogrammetric training at the same time requires an easy to learn, straight forward surveying technique. A photogrammetric method was developed aimed primarily at earth scientists for taking accurate measurements in the field minimizing extra bulk and weight of the required equipment. The work included several challenges. A) Definition of an upright coordinate system without heavy and bulky tools like a total station or GNS-Sensor. B) Optimization of image acquisition and geometric stability of the image block. C) Identification of a small camera suitable for precise measurements in the field. D) Optimization of the workflow from image acquisition to preparation of images for stereo measurements. E) Introduction of students and non-photogrammetrists to the workflow. Wooden spheres were used as target points in the field. They were more rugged and available in different sizes than ping pong balls used in a previous setup. Distances between three spheres were introduced as scale information in a photogrammetric adjustment. The distances were measured with a laser distance meter accurate to 1 mm (1 sigma). The vertical angle between the spheres was measured with the same laser distance meter. The precision of the measurement was 0.3° (1 sigma) which is sufficient, i.e. better than inclination measurements with a geological compass. The upright

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.

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

Early detection of breast cancer: benefits and risks of supplemental breast ultrasound in asymptomatic women with mammographically dense breast tissue. A systematic review

International Nuclear Information System (INIS)

Nothacker, Monika; Duda, Volker; Hahn, Markus; Warm, Mathias; Degenhardt, Friedrich; Madjar, Helmut; Weinbrenner, Susanne; Albert, Ute-Susann

2009-01-01

the application to women age 50-69 years as proposed for mammographic screening could result in less striking benefit. Further validation studies should employ a uniform assessment system such as BI-RADS and report not only PPV, but also negative predictive value, sensitivity and specificity. Supplemental breast ultrasound in the population of women with mammographically dense breast tissue (ACR 3 and 4) permits detection of small, otherwise occult, breast cancers. Potential adverse impacts for women in this intermediate risk group are associated with an increased biopsy rate

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.)

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.)

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.

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

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.

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 ...

Retrospective analysis of a Computer-Aided Detection (CAD) system in full-field digital mammography in correlation to tumor histology

International Nuclear Information System (INIS)

Obenauer, S.; Sohns, C.; Grabbe, E.; Werner, C.

2005-01-01

Purpose: to evaluate the usefulness of a computer-aided detection (CAD) system in full-field digital mammography in correlation to tumor histology. Material and methods: a total of 476 patients (226 patients with histologically proven malignant tumors, 250 healthy women) took part in this study. The mammograms were studied retrospectively, using the CAD system Image Checker. For 226 patients digital mammograms in MLO-projection were available. For 186 of these patients the CC-projection was also available. CAD markers that correlated with histologically proven carcinomas were considered to be true-positive markers. All other CAD markers were considered to be false-positive. Histologically proven carcinomas without markers were false-negative results. The dependence of the CAD markers placement upon the different carcinoma histologies was studied using the Chi-square test. Results: no significant difference could be proven for the detectability of malignant breast lesions of different histologic types. For the detectability of ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), lobular carcinoma in situ (LCIS), tubular carcinoma and ductulo-lobular carcinoma, the true positives were 71.1%, 75%, 70.7%, 70%, 60% and 80%, respectively, in the MLO projection and 83.9%, 75.9%, 81.8%, 77.8%, 87.5% and 33.3%, respectively, in the CC projection. There was an average of 0.5 false-positive markers per mammographic image. Conclusion: The histologic type of carcinoma seems to have no influence on detectability when using the CAD system. The high rate of false-positive markers shows, however, the limited specificity of the CAD system and that improvements are necessary. (orig.)

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

Mammographic and sonographic findings of steatocystoma multiplex presenting as breast lumps.

Science.gov (United States)

Wan, John Mun Chin; Wong, Jill Su Lin; Tee, Shang-Ian

2012-12-01

Steatocystoma multiplex (SM) is an uncommon cutaneous disorder characterised by multiple intradermal cysts distributed over the trunk and proximal extremities. This condition affects both genders and is often inherited as an autosomal dominant trait, although sporadic cases have been described. This report describes the mammographic and sonographic features of the cysts, which presented as breast lumps, for evaluation. The cysts appeared as numerous well-circumscribed, radiolucent nodules with thin radiodense rims on mammography. On sonography, the cysts could be hypoechoic, isoechoic or demonstrate mixed echoes containing debris-fluid levels, depending on the amount of clear oily liquid and keratinous material. SM can be diagnosed based on a clinical setting of multiple asymptomatic small intradermal nodules over the trunk and proximal extremities, positive family history and imaging findings.

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.

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

A new approach to develop computer-aided detection schemes of digital mammograms

Science.gov (United States)

Tan, Maxine; Qian, Wei; Pu, Jiantao; Liu, Hong; Zheng, Bin

2015-06-01

The purpose of this study is to develop a new global mammographic image feature analysis based computer-aided detection (CAD) scheme and evaluate its performance in detecting positive screening mammography examinations. A dataset that includes images acquired from 1896 full-field digital mammography (FFDM) screening examinations was used in this study. Among them, 812 cases were positive for cancer and 1084 were negative or benign. After segmenting the breast area, a computerized scheme was applied to compute 92 global mammographic tissue density based features on each of four mammograms of the craniocaudal (CC) and mediolateral oblique (MLO) views. After adding three existing popular risk factors (woman’s age, subjectively rated mammographic density, and family breast cancer history) into the initial feature pool, we applied a sequential forward floating selection feature selection algorithm to select relevant features from the bilateral CC and MLO view images separately. The selected CC and MLO view image features were used to train two artificial neural networks (ANNs). The results were then fused by a third ANN to build a two-stage classifier to predict the likelihood of the FFDM screening examination being positive. CAD performance was tested using a ten-fold cross-validation method. The computed area under the receiver operating characteristic curve was AUC = 0.779   ±   0.025 and the odds ratio monotonically increased from 1 to 31.55 as CAD-generated detection scores increased. The study demonstrated that this new global image feature based CAD scheme had a relatively higher discriminatory power to cue the FFDM examinations with high risk of being positive, which may provide a new CAD-cueing method to assist radiologists in reading and interpreting screening mammograms.

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]).

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

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.

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...

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 ...

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.)

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.

General temperature field measurement by digital holography

Czech Academy of Sciences Publication Activity Database

Doleček, Roman; Psota, Pavel; Lédl, Vít; Vít, Tomáš; Václavík, Jan; Kopecký, V.

2013-01-01

Roč. 52, č. 1 (2013), A319-A325 ISSN 1559-128X Institutional support: RVO:61389021 Keywords : digital holography * temperature field measurement * tomography Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.649, year: 2013

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...

Towards 3C-3D digital holographic fluid velocity vector field measurement—tomographic digital holographic PIV (Tomo-HPIV)

International Nuclear Information System (INIS)

Soria, J; Atkinson, C

2008-01-01

Most unsteady and/or turbulent flows of geophysical and engineering interest have a highly three-dimensional (3D) complex topology and their experimental investigation is in pressing need of quantitative velocity measurement methods that are robust and can provide instantaneous 3C-3D velocity field data over a significant volumetric domain of the flow. This paper introduces and demonstrates a new method that uses multiple digital CCD array cameras to record in-line digital holograms of the same volume of seed particles from multiple orientations. This technique uses the same basic equipment as Tomo-PIV minus the camera lenses, it overcomes the depth-of-field problem of digital in-line holography and does not require the complex optical calibration of Tomo-PIV. The digital sensors can be oriented in an optimal manner to overcome the depth-of-field limitation of in-line holograms recorded using digital CCD or CMOS array cameras, resulting in a 3D reconstruction of the seed particles within the volume of interest, which can subsequently be analysed using 3D cross-correlation PIV analysis to yield a 3C-3D velocity field. A demonstration experiment of Tomo-HPIV using uniform translation with nominally 11 µm diameter seed particles shows that the 3D displacement derived from 3D cross-correlation Tomo-HPIV analysis can be measured within 5% of the imposed uniform translation, where the imposed uniform translation has an estimated standard uncertainty of 4.3%. So this paper proposes a multi-camera digital holographic imaging 3C-3D PIV method, which is identified as tomographic digital holographic PIV or Tomo-HPIV

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

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

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.

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

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

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

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....

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)

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)

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.

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

Small forest cuttings mapped with Landsat digital data

Science.gov (United States)

Bryant, E.; Dodge, A. G.; Eger, M. J. E.

1979-01-01

The Cooperative Landsat Applications Research Group used computer classification of Landsat digital data to map forest cuttings (clearcuts) in northern New Hampshire. Cuttings as small as 3 hectares were identified. Several ages or conditions of clearcuts could be distinguished. Progress in two methods of duplicating classification categories from one Landsat pass to another are discussed. One method was used in making maps of areas in 1973, 1975, and 1978.

Effect of the Availability of Prior Full-Field Digital Mammography and Digital Breast Tomosynthesis Images on the Interpretation of Mammograms

Science.gov (United States)

Catullo, Victor J.; Chough, Denise M.; Ganott, Marie A.; Kelly, Amy E.; Shinde, Dilip D.; Sumkin, Jules H.; Wallace, Luisa P.; Bandos, Andriy I.; Gur, David

2015-01-01

Purpose To assess the effect of and interaction between the availability of prior images and digital breast tomosynthesis (DBT) images in decisions to recall women during mammogram interpretation. Materials and Methods Verbal informed consent was obtained for this HIPAA-compliant institutional review board–approved protocol. Eight radiologists independently interpreted twice deidentified mammograms obtained in 153 women (age range, 37–83 years; mean age, 53.7 years ± 9.3 [standard deviation]) in a mode by reader by case-balanced fully crossed study. Each study consisted of current and prior full-field digital mammography (FFDM) images and DBT images that were acquired in our facility between June 2009 and January 2013. For one reading, sequential ratings were provided by using (a) current FFDM images only, (b) current FFDM and DBT images, and (c) current FFDM, DBT, and prior FFDM images. The other reading consisted of (a) current FFDM images only, (b) current and prior FFDM images, and (c) current FFDM, prior FFDM, and DBT images. Fifty verified cancer cases, 60 negative and benign cases (clinically not recalled), and 43 benign cases (clinically recalled) were included. Recall recommendations and interaction between the effect of prior FFDM and DBT images were assessed by using a generalized linear model accounting for case and reader variability. Results Average recall rates in noncancer cases were significantly reduced with the addition of prior FFDM images by 34% (145 of 421) and 32% (106 of 333) without and with DBT images, respectively (P < .001). However, this recall reduction was achieved at the cost of a corresponding 7% (23 of 345) and 4% (14 of 353) reduction in sensitivity (P = .006). In contrast, availability of DBT images resulted in a smaller reduction in recall rates (false-positive interpretations) of 19% (76 of 409) and 26% (71 of 276) without and with prior FFDM images, respectively (P = .001). Availability of DBT images resulted in 4% (15 of

Spectral distribution of particle fluence in small field detectors and its implication on small field dosimetry.

Science.gov (United States)

Benmakhlouf, Hamza; Andreo, Pedro

2017-02-01

Correction factors for the relative dosimetry of narrow megavoltage photon beams have recently been determined in several publications. These corrections are required because of the several small-field effects generally thought to be caused by the lack of lateral charged particle equilibrium (LCPE) in narrow beams. Correction factors for relative dosimetry are ultimately necessary to account for the fluence perturbation caused by the detector. For most small field detectors the perturbation depends on field size, resulting in large correction factors when the field size is decreased. In this work, electron and photon fluence differential in energy will be calculated within the radiation sensitive volume of a number of small field detectors for 6 MV linear accelerator beams. The calculated electron spectra will be used to determine electron fluence perturbation as a function of field size and its implication on small field dosimetry analyzed. Fluence spectra were calculated with the user code PenEasy, based on the PENELOPE Monte Carlo system. The detectors simulated were one liquid ionization chamber, two air ionization chambers, one diamond detector, and six silicon diodes, all manufactured either by PTW or IBA. The spectra were calculated for broad (10 cm × 10 cm) and narrow (0.5 cm × 0.5 cm) photon beams in order to investigate the field size influence on the fluence spectra and its resulting perturbation. The photon fluence spectra were used to analyze the impact of absorption and generation of photons. These will have a direct influence on the electrons generated in the detector radiation sensitive volume. The electron fluence spectra were used to quantify the perturbation effects and their relation to output correction factors. The photon fluence spectra obtained for all detectors were similar to the spectrum in water except for the shielded silicon diodes. The photon fluence in the latter group was strongly influenced, mostly in the low-energy region, by

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

Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

International Nuclear Information System (INIS)

Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina

2012-01-01

Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., “FOR PROCESSING”) and vendor postprocessed (i.e., “FOR PRESENTATION”), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely fibroglandular, which

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...

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

Digitizing specimens in a small herbarium: A viable workflow for collections working with limited resources.

Science.gov (United States)

Harris, Kari M; Marsico, Travis D

2017-04-01

Small herbaria represent a significant portion of herbaria in the United States, but many are not digitizing their collections. At the Arkansas State University Herbarium (STAR), we have created a viable workflow to help small herbaria begin the digitization process, including suggestions for publishing data on the Internet. We calculated hourly rates of each phase of the digitization process. We also mapped accessions at the county level to determine geographic strengths in the collection. All 17,678 accessioned flowering plant specimens at STAR are imaged, databased in Specify, and available electronically on the herbarium's website. Students imaged the specimens at a mean rate of 145/h. We found differences in databasing rates between the graduate student leading the project (47/h) and undergraduate assistants (25/h). The majority of specimens at STAR were collected within the counties neighboring the institution. With this workflow, we estimate that one person can digitize a 20,000-specimen collection in less than 2.5 yr by working only 10 h/wk. Because STAR is a small herbarium with limited resources, the application of the workflow described should assist curators of similar-sized collections as they contemplate and undertake the digitization process.

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.

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...

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...

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...

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...

Field-Programmable Gate Array-based fluxgate magnetometer with digital integration

Science.gov (United States)

Butta, Mattia; Janosek, Michal; Ripka, Pavel

2010-05-01

In this paper, a digital magnetometer based on printed circuit board fluxgate is presented. The fluxgate is pulse excited and the signal is extracted by gate integration. We investigate the possibility to perform integration on very narrow gates (typically 500 ns) by using digital techniques. The magnetometer is based on field-programmable gate array (FPGA) card: we will show all the advantages and disadvantages, given by digitalization of fluxgate output voltage by means of analog-to-digital converter on FPGA card, as well as digitalization performed by external digitizer. Due to very narrow gate, it is shown that a magnetometer entirely based on a FPGA card is preferable, because it avoids noise due to trigger instability. Both open loop and feedback operative mode are described and achieved results are presented.

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

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

International Nuclear Information System (INIS)

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

2009-01-01

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

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

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

Development of a volumetric projection technique for the digital evaluation of field of view.

Science.gov (United States)

Marshall, Russell; Summerskill, Stephen; Cook, Sharon

2013-01-01

Current regulations for field of view requirements in road vehicles are defined by 2D areas projected on the ground plane. This paper discusses the development of a new software-based volumetric field of view projection tool and its implementation within an existing digital human modelling system. In addition, the exploitation of this new tool is highlighted through its use in a UK Department for Transport funded research project exploring the current concerns with driver vision. Focusing specifically on rearwards visibility in small and medium passenger vehicles, the volumetric approach is shown to provide a number of distinct advantages. The ability to explore multiple projections of both direct vision (through windows) and indirect vision (through mirrors) provides a greater understanding of the field of view environment afforded to the driver whilst still maintaining compatibility with the 2D projections of the regulatory standards. Field of view requirements for drivers of road vehicles are defined by simplified 2D areas projected onto the ground plane. However, driver vision is a complex 3D problem. This paper presents the development of a new software-based 3D volumetric projection technique and its implementation in the evaluation of driver vision in small- and medium-sized passenger vehicles.

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

Assessing diabetic retinopathy using two-field digital photography and the influence of JPEG-comoression

NARCIS (Netherlands)

Stellingwerf, C; Hardus, PLLJ; Hooymans, JMM

Objective: To study the effectiveness of two digital 50degrees photographic fields per eye, stored compressed or integrally, in the grading of diabetic retinopathy, in comparison to 35-mm colour slides. Subjects and methods: Two-field digital non-stereoscopic retinal photographs and two-field 35-mm

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%

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.

The measurement of the modal strain fields using digital shearography

Directory of Open Access Journals (Sweden)

Gomes J.M.

2010-06-01

Full Text Available This work presents a Michelson shearography interferometer configuration associated with stroboscopic double illumination technique for the measurement of modal rotation fields and their strain fields on a clamped circular aluminium plate. The speckle pattern is frozen by the synchronization between the LASER illumination and the modal vibration of the object. The quantitative evaluation is performed for each digital shearogram using a time modulation technique. The setup of double illumination LASER with out-of-plane opposite sensitivity allows the two phase maps measurement of the modal spatial gradient. The modal rotation and strain fields are extracted by the combination of this two digital phase maps. Image processing techniques are applied on the phase maps to obtain full-field measurements using a dedicated post-processing algorithm. Finally, is presented a comparison between the experimental measurement and the numerical solution.

Red clover-derived isoflavones and mammographic breast density: a double-blind, randomized, placebo-controlled trial [ISRCTN42940165

International Nuclear Information System (INIS)

Atkinson, Charlotte; Warren, Ruth ML; Sala, Evis; Dowsett, Mitch; Dunning, Alison M; Healey, Catherine S; Runswick, Shirley; Day, Nicholas E; Bingham, Sheila A

2004-01-01

Isoflavones are hypothesized to protect against breast cancer, but it is not clear whether they act as oestrogens or anti-oestrogens in breast tissue. Our aim was to determine the effects of taking a red clover-derived isoflavone supplement daily for 1 year on mammographic breast density. Effects on oestradiol, follicle-stimulating hormone (FSH), luteinizing hormone (LH), lymphocyte tyrosine kinase activity and menopausal symptoms were also assessed. A total of 205 women (age range 49–65 years) with Wolfe P2 or DY mammographic breast patterns were randomly assigned to receive either a red clover-derived isoflavone tablet (26 mg biochanin A, 16 mg formononetin, 1 mg genistein and 0.5 mg daidzein) or placebo. Change in mammographic breast density, serum oestradiol, FSH, LH, menopausal symptoms and lymphocyte tyrosine kinase activity from baseline to 12 months were assessed. A total of 177 women completed the trial. Mammographic breast density decreased in both groups but the difference between the treatment and placebo was not statistically significant. There was a significant interaction between treatment group and oestrogen receptor (ESR1) PvuII polymorphism for the change in estimated percentage breast density (mean ± standard deviation): TT isoflavone 1.4 ± 12.3% and TT placebo -9.6 ± 14.2%; CT isoflavone -5.2 ± 12.0% and CT placebo -2.8 ± 10.3%; and CC isoflavone -3.4 ± 9.7% and CC placebo -1.1 ± 9.5%. There were no statistically significant treatment effects on oestradiol, FSH, or LH (assessed only in postmenopausal women), or on lymphocyte tyrosine kinase activity. Baseline levels of menopausal symptoms were low, and there were no statistically significant treatment effects on frequency of hot flushes or other menopausal symptoms. In contrast to studies showing that conventional hormone replacement therapies increase mammographic breast density, the isoflavone supplement did not increase mammographic breast density in this population of women

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 ...

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

The sensitivity and specificity of one field non-mydriatic digital fundus photography for DR screening

Directory of Open Access Journals (Sweden)

Bin-Bin Li

2013-07-01

Full Text Available AIM:To evaluate the sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy for diabetic retinopathy(DRscreening, compared with fundus fluorescein angiography( FFA .METHODS:All 93 patients of type 1 or 2 diabetic who have underwent one-field non-mydriatic digital fundus photography, and direct ophthalmoscopy with dilation of their pupils, and FFA by ophthalmologists. The sensitivity and specificity of one-field non-mydriatic digital fundus photography and direct ophthalmoscopy were calculated respectively, compared with FFA.RESULTS: The sensitivity and specificity of one-field non-mydriatic digital fundus photography for detection of any DR were 80.4% and 94.7%; The sensitivity and specificity of direct ophthalmoscopy for detection of any DR were 64.2% and 84.2%; After the standard for referable DR being lowered down to the moderate non-proliferative diabetic retinopathy(M-NPDR, the sensitivity and specificity of non-mydriatic digital fundus photography for detection were 88.9% and 98.4%, the sensitivity and specificity of direct ophthalmoscopy for detection were 71.5% and 96.7%.CONCLUSION: One-field non-mydriatic digital fundus photography is an effective method for DR screening.

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.

Acceptance testing in digital systens 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 minimun radiation dose compatible with an image quality sutiable for diagnose purposes. The aim of this study is to assess the practical applicability of different protocols in acceptance test of digital mammographyc systems. This study has been carried out on the results of ltyhe 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 oin 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 authomatic 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.

Digital Field Mapping with the British Geological Survey

Science.gov (United States)

Leslie, Graham; Smith, Nichola; Jordan, Colm

2014-05-01

The BGS•SIGMA project was initiated in 2001 in response to a major stakeholder review of onshore mapping within the British Geological Survey (BGS). That review proposed a significant change for BGS with the recommendation that digital methods should be implemented for field mapping and data compilation. The BGS•SIGMA project (System for Integrated Geoscience MApping) is an integrated workflow for geoscientific surveying and visualisation using digital methods for geological data visualisation, recording and interpretation, in both 2D and 3D. The project has defined and documented an underpinning framework of best practice for survey and information management, best practice that has then informed the design brief and specification for a toolkit to support this new methodology. The project has now delivered BGS•SIGMA2012. BGS•SIGMA2012 is a integrated toolkit which enables assembly and interrogation/visualisation of existing geological information; capture of, and integration with, new data and geological interpretations; and delivery of 3D digital products and services. From its early days as a system which used PocketGIS run on Husky Fex21 hardware, to the present day system which runs on ruggedized tablet PCs with integrated GPS units, the system has evolved into a complete digital mapping and compilation system. BGS•SIGMA2012 uses a highly customised version of ESRI's ArcGIS 10 and 10.1 with a fully relational Access 2007/2010 geodatabase. BGS•SIGMA2012 is the third external release of our award-winning digital field mapping toolkit. The first free external release of the award-winning digital field mapping toolkit was in 2009, with the third version (BGS-SIGMAmobile2012 v1.01) released on our website (http://www.bgs.ac.uk/research/sigma/home.html) in 2013. The BGS•SIGMAmobile toolkit formed the major part of the first two releases but this new version integrates the BGS•SIGMAdesktop functionality that BGS routinely uses to transform our field

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.

Methods for small RNA preparation for digital gene expression profiling by next-generation sequencing

NARCIS (Netherlands)

Linsen, S.E.V.; Cuppen, E.

2012-01-01

Digital gene expression (DGE) profiling techniques are playing an eminent role in the detection, localization, and differential expression quantification of many small RNA species, including microRNAs (1-3). Procedures in small RNA library preparation techniques typically include adapter ligation by

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.

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.

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

International Nuclear Information System (INIS)

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

2005-01-01

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

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Digitizing specimens in a small herbarium: A viable workflow for collections working with limited resources1

Science.gov (United States)

Harris, Kari M.; Marsico, Travis D.

2017-01-01

Premise of the study: Small herbaria represent a significant portion of herbaria in the United States, but many are not digitizing their collections. Methods: At the Arkansas State University Herbarium (STAR), we have created a viable workflow to help small herbaria begin the digitization process, including suggestions for publishing data on the Internet. We calculated hourly rates of each phase of the digitization process. We also mapped accessions at the county level to determine geographic strengths in the collection. Results: All 17,678 accessioned flowering plant specimens at STAR are imaged, databased in Specify, and available electronically on the herbarium’s website. Students imaged the specimens at a mean rate of 145/h. We found differences in databasing rates between the graduate student leading the project (47/h) and undergraduate assistants (25/h). The majority of specimens at STAR were collected within the counties neighboring the institution. Discussion: With this workflow, we estimate that one person can digitize a 20,000-specimen collection in less than 2.5 yr by working only 10 h/wk. Because STAR is a small herbarium with limited resources, the application of the workflow described should assist curators of similar-sized collections as they contemplate and undertake the digitization process. PMID:28439474

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

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

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

International Nuclear Information System (INIS)

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

2014-01-01

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

THE HIGH-PERFORMANCE RESOURCE-SPARING TECHNOLOGIES IN THE DIAGNOSTIC MAMMOLOGY (On the fifth anniversary of the Russian association of mammologists

Directory of Open Access Journals (Sweden)

N. I. Rozhkova

2008-01-01

Full Text Available There have been presented the main achievements in the field of mammologic service development in Russia owing to creation and introduction of the domestic mammographic stationary digital and mobile mammographs, organization of the system of the continuous education of the specialists on basis of interdisciplinary integration, as well as introduction of the novel technologies of the radiologi- cal examination, interventional radiology, molecular biology, informational technologies, realization of the wide-ranging information- al educational work. The diagnostic mammology development perspectives are outlined.

Stellarator fields with small PS current at small rotational transform

International Nuclear Information System (INIS)

Herrnegger, F.

2001-01-01

One aspect of the optimization concept of stellarators is the reduction of the normalized Pfirsch-Schlueter current density p arallel 2 / j p erpendikular 2 > 1/2 to a reasonable level but obeying other side conditions, e.g., concerning small bootstrap currents, good stability properties, reasonable aspect ratio, etc. This problem is addressed in the present work. Various stellarator vacuum field are given analytically for M 2, 3, 5, 10, 12 (M is the number of field period around the torus) where the PS-current density is reduced by more than a factor of ten to rather small values around 0.3 even at small i-values

An iPad and Android-based Application for Digitally Recording Geologic Field Data

Science.gov (United States)

Malinconico, L. L.; Sunderlin, D.; Liew, C.; Ho, A. S.; Bekele, K. A.

2011-12-01

Field experience is a significant component in most geology courses, especially sed/strat and structural geology. Increasingly, the spatial presentation, analysis and interpretation of geologic data is done using digital methodologies (GIS, Google Earth, stereonet and spreadsheet programs). However, students and professionals continue to collect field data manually on paper maps and in the traditional "orange field notebooks". Upon returning from the field, data are then manually transferred into digital formats for processing, mapping and interpretation. The transfer process is both cumbersome and prone to transcription error. In conjunction with the computer science department, we are in the process of developing an application (App) for iOS (the iPad) and Android platforms that can be used to digitally record data measured in the field. This is not a mapping program, but rather a way of bypassing the field book step to acquire digital data directly that can then be used in various analysis and display programs. Currently, the application allows the user to select from five different structural data situations: contact, bedding, fault, joints and "other". The user can define a folder for the collection and separation of data for each project. Observations are stored as individual records of field measurements in each folder. The exact information gathered depends on the nature of the observation, but common to all pages is the ability to log date, time, and lat/long directly from the tablet. Information like strike and dip are entered using scroll wheels and formation names are also entered using scroll wheels that access easy-to-modify lists of the area's stratigraphic units. This insures uniformity in the creation of the digital records from day-to-day and across field teams. Pictures can also be taken using the tablet's camera that are linked to each record. Once the field collection is complete the data (including images) can be easily exported to a .csv file

Probing Dense Sprays with Gated, Picosecond, Digital Particle Field Holography

Directory of Open Access Journals (Sweden)

James Trolinger

2011-12-01

Full Text Available This paper describes work that demonstrated the feasibility of producing a gated digital holography system that is capable of producing high-resolution images of three-dimensional particle and structure details deep within dense particle fields of a spray. We developed a gated picosecond digital holocamera, using optical Kerr cell gating, to demonstrate features of gated digital holography that make it an exceptional candidate for this application. The Kerr cell gate shuttered the camera after the initial burst of ballistic and snake photons had been recorded, suppressing longer path, multiple scattered illumination. By starting with a CW laser without gating and then incorporating a picosecond laser and an optical Kerr gate, we were able to assess the imaging quality of the gated holograms, and determine improvement gained by gating. We produced high quality images of 50–200 μm diameter particles, hairs and USAF resolution charts from digital holograms recorded through turbid media where more than 98% of the light was scattered from the field. The system can gate pulses as short as 3 mm in pathlength (10 ps, enabling image-improving features of the system. The experiments lead us to the conclusion that this method has an excellent capability as a diagnostics tool in dense spray combustion research.

An overview of digital image processing in the field of nuclear medicine

International Nuclear Information System (INIS)

Okuyama, Yasuo

1992-01-01

The current status and remaining problems of digital image processing in nuclear medicine were discussed. Digitalization of nuclear medicine images has made it possible, in conjunction with computers, to obtain new information (Fourier analysis, Factor analysis, etc.) with added value from images, in place of the fixed concepts that had formerly been drawn only from images. However, the basis of this technology is the special QC and QA of nuclear medicine examinations, and those techniques have not yet been adequately established. The advantage of digitalization is the flexibility that comes from the programs, but the element of the subjectivity of each individual plays a large role, and it can be said that there is also the risk that the logic of image diagnosis established to date will be destroyed. Accordingly, the creation of digital image processing technique with specifications will give birth to standardized digital nuclear medicine images, and these development will certainly lead to progress in nuclear medicine diagnosis. In addition, in comparison with other modalities, the field of nuclear medicine involves a lesser amount of information, and this simplifiers the digitalization of images. At present, equipment is being designed and developed with incorporation of the concept of a work station. A serious problem that remains in this field is the standardization of image transmission. In summary, the main problem that must be solved in the field of nuclear medicine examinations is the establishment of QC and QA methods and practical algorithms for the software. It is hoped that there will be open access to information, etc., related to the software. (author)

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...

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.

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.

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

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

International Nuclear Information System (INIS)

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

2006-01-01

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

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

Field-programmable beam reconfiguring based on digitally-controlled coding metasurface

Science.gov (United States)

Wan, Xiang; Qi, Mei Qing; Chen, Tian Yi; Cui, Tie Jun

2016-02-01

Digital phase shifters have been applied in traditional phased array antennas to realize beam steering. However, the phase shifter deals with the phase of the induced current; hence, it has to be in the path of each element of the antenna array, making the phased array antennas very expensive. Metamaterials and/or metasurfaces enable the direct modulation of electromagnetic waves by designing subwavelength structures, which opens a new way to control the beam scanning. Here, we present a direct digital mechanism to control the scattered electromagnetic waves using coding metasurface, in which each unit cell loads a pin diode to produce binary coding states of “1” and “0”. Through data lines, the instant communications are established between the coding metasurface and the internal memory of field-programmable gate arrays (FPGA). Thus, we realize the digital modulation of electromagnetic waves, from which we present the field-programmable reflective antenna with good measurement performance. The proposed mechanism and functional device have great application potential in new-concept radar and communication systems.

Digital Controller For Acoustic Levitation

Science.gov (United States)

Tarver, D. Kent

1989-01-01

Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

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

The Place of Digital Marketing on Turkish Small Businesses

OpenAIRE

Serhat Karatum

2017-01-01

In the 21st century, technology develops rapidly and continuously and it affects every aspect of our lives. Marketing concept has been affected by these developments. What we want from marketing and reaching in an increasingly virtualized world is to be a lot faster than the past. Also, new marketing channels have emerged as well. Turkish small businesses, the building blocks of Turkish economy, have the chance of addressing the marketing problems and solving the problems with the digital mar...

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).

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...

Model-based estimation of breast percent density in raw and processed full-field digital mammography images from image-acquisition physics and patient-image characteristics

Science.gov (United States)

Keller, Brad M.; Nathan, Diane L.; Conant, Emily F.; Kontos, Despina

2012-03-01

Breast percent density (PD%), as measured mammographically, is one of the strongest known risk factors for breast cancer. While the majority of studies to date have focused on PD% assessment from digitized film mammograms, digital mammography (DM) is becoming increasingly common, and allows for direct PD% assessment at the time of imaging. This work investigates the accuracy of a generalized linear model-based (GLM) estimation of PD% from raw and postprocessed digital mammograms, utilizing image acquisition physics, patient characteristics and gray-level intensity features of the specific image. The model is trained in a leave-one-woman-out fashion on a series of 81 cases for which bilateral, mediolateral-oblique DM images were available in both raw and post-processed format. Baseline continuous and categorical density estimates were provided by a trained breast-imaging radiologist. Regression analysis is performed and Pearson's correlation, r, and Cohen's kappa, κ, are computed. The GLM PD% estimation model performed well on both processed (r=0.89, p<0.001) and raw (r=0.75, p<0.001) images. Model agreement with radiologist assigned density categories was also high for processed (κ=0.79, p<0.001) and raw (κ=0.76, p<0.001) images. Model-based prediction of breast PD% could allow for a reproducible estimation of breast density, providing a rapid risk assessment tool for clinical practice.

Monte Carlo simulation of small field electron beams for small animal irradiation

International Nuclear Information System (INIS)

Lee, Chung-Chi; Chen, Ai-Mei; Tung, Chuan-Jong; Chao, Tsi-Chian

2011-01-01

The volume effect of detectors in the dosimetry of small fields for photon beams has been well studied due to interests in radiosurgery and small beamlets used in IMRT treatments; but there is still an unexplored research field for small electron beams used in small animal irradiation. This study proposes to use the BEAM Monte Carlo (MC) simulation to assess characteristics of small electron beams (4, 6, 14, 30 mm in diameter) with the kinetic energies of 6 and 18 MeV. Three factors influencing beam characteristics were studied (1) AE and ECUT settings, (2) photon jaw settings and (3) simulation pixel sizes. Study results reveal that AE/ECUT settings at 0.7 MeV are adequate for linear accelerator treatment head simulation, while 0.521 MeV is more favorable to be used for the phantom study. It is also demonstrated that voxel size setting at 1/4 of the simulation field width in all directions is sufficient to achieve accurate results. As for the photon jaw setting, it has great impact on the absolute output of different field size setting (i.e. output factor) but with minimum effect on the relative lateral distribution.

Dose reduction through gridless technique in digital full-field mammography

International Nuclear Information System (INIS)

Diekmann, F.; Diekmann, S.; Berzeg, S.; Blick, U.; Fischer, T.; Hamm, B.

2003-01-01

Purpose: To determine the role of the scatter grid in digital full-field mammography with respect to image quality and dose and to compare the experimental results with initial clinical experience. Materials and Methods: A phantom consisting of 205 fields that enclose gold dots of different thickness and size (CD-Mam phantom, Medical Department, Nijmegen, Netherlands) was used for digital full-field mammography with the conventional grid module and a special gridless module. Four different breast thicknesses were simulated using Plexiglas as scatter material. First, the phantom was exposed at the parameter and dose settings automatically selected in each experimental setup (with and without grid). Subsequently, the phantom was exposed at the different simulated breast thicknesses using the gridless module in combination with the parameters automatically selected for the grid module. This was followed by a series of phantom mammograms obtained with the experimental setup reversed. The 16 mammograms were evaluated by 3 readers and the results compared considering breast thickness, radiation dose, and quality. The gridless module was used for preoperative labeling in 16 patients for comparison of mammograms obtained with and without a grid. Results: For the same entrance dose used in routine mammography, digital mammography without grid is superior to digital mammography with grid when performed on simulated thin breasts (Plexiglas less than 3 cm), with no difference found when performed on simulated large breasts. The advantages of gridless mammography are more pronounced at a markedly reduced entrance dose (identical parenchymal dose without and with grid using the dose automatically selected for the gridless module). This tendency is confirmed by the initial clinical comparison. (orig.) [de

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

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.)

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

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)

Can we see enough? A comparative study of film-screen vs digital radiographs in small lesions in rheumatoid arthritis

International Nuclear Information System (INIS)

Jagt, E.J. van der; Hofman, S.; Kraft, B.M.; Leeuwen, M.A. van

2000-01-01

The aim of this study was to evaluate the performance of digital radiography in the detection of early very small erosions and joint space narrowing in the hands and feet in rheumatoid arthritis. Fifty-three sets of film-screen and digital radiographs of the same hands and feet with very small and sometimes questionable lesions (possible erosions and cysts) were scored independently two times by four investigators. The percentage of lesions found in exactly the same position for each investigator was calculated. Intra-observer agreement between first and second reading in film-screen radiography was 64-76 % (mean 67 %), and in digital radiographs 60-71 % (mean 64 %). Agreement between film-screen and digital radiographs ranged from 54 to 64 % (mean 58 %) in the first reading and from 56 to 66 % (mean 62 %) in the second reading. Overall agreement between both techniques between first and second reading ranged between 62 and 73 % (mean 65 %). Digital radiography of the hands and feet can be used in patients suspected of rheumatoid arthritis and in follow-up of those patients, because small and early erosions can be seen equally well with the digital technique as compared with the conventional film-screen technique. (orig.)

Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

Energy Technology Data Exchange (ETDEWEB)

Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina [Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Applied Mathematics and Computational Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2012-08-15

Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., 'FOR PROCESSING') and vendor postprocessed (i.e., 'FOR PRESENTATION'), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely

Application of Field programmable Gate Array to Digital Signal ...

African Journals Online (AJOL)

Journal of Research in National Development ... This work shows how one parallel technology Field Programmable Gate Array (FPGA) can be applied to digital signal processing problem to increase computational speed. ... In this research work FPGA typically exploits parallelism because FPGA is a parallel device. With the ...

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)

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

Digital loyalty card "big data' and small business marketing: Formal versus informal or complementary?

OpenAIRE

Donnelly, Christina; Simmons, Geoff; Armstrong, Gillian; Fearne, Andrew

2015-01-01

This article proposes that a complementary relationship exists between the formalised nature of digital loyalty card data, and the informal nature of small business market orientation. A longitudinal, case-based research approach analysed this relationship in small firms given access to Tesco Clubcard data. The findings reveal a new-found structure and precision in small firm marketing planning from data exposure; this complemented rather than conflicted with an intuitive feel for markets. In...

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.

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

Breast Imaging Reporting and Data System (BI-RADS) breast composition descriptors: Automated measurement development for full field digital mammography

International Nuclear Information System (INIS)

Fowler, E. E.; Sellers, T. A.; Lu, B.; Heine, J. J.

2013-01-01

Purpose: The Breast Imaging Reporting and Data System (BI-RADS) breast composition descriptors are used for standardized mammographic reporting and are assessed visually. This reporting is clinically relevant because breast composition can impact mammographic sensitivity and is a breast cancer risk factor. New techniques are presented and evaluated for generating automated BI-RADS breast composition descriptors using both raw and calibrated full field digital mammography (FFDM) image data.Methods: A matched case-control dataset with FFDM images was used to develop three automated measures for the BI-RADS breast composition descriptors. Histograms of each calibrated mammogram in the percent glandular (pg) representation were processed to create the new BR pg measure. Two previously validated measures of breast density derived from calibrated and raw mammograms were converted to the new BR vc and BR vr measures, respectively. These three measures were compared with the radiologist-reported BI-RADS compositions assessments from the patient records. The authors used two optimization strategies with differential evolution to create these measures: method-1 used breast cancer status; and method-2 matched the reported BI-RADS descriptors. Weighted kappa (κ) analysis was used to assess the agreement between the new measures and the reported measures. Each measure's association with breast cancer was evaluated with odds ratios (ORs) adjusted for body mass index, breast area, and menopausal status. ORs were estimated as per unit increase with 95% confidence intervals.Results: The three BI-RADS measures generated by method-1 had κ between 0.25–0.34. These measures were significantly associated with breast cancer status in the adjusted models: (a) OR = 1.87 (1.34, 2.59) for BR pg ; (b) OR = 1.93 (1.36, 2.74) for BR vc ; and (c) OR = 1.37 (1.05, 1.80) for BR vr . The measures generated by method-2 had κ between 0.42–0.45. Two of these measures were significantly

Volumetric breast density estimation from full-field digital mammograms.

NARCIS (Netherlands)

Engeland, S. van; Snoeren, P.R.; Huisman, H.J.; Boetes, C.; Karssemeijer, N.

2006-01-01

A method is presented for estimation of dense breast tissue volume from mammograms obtained with full-field digital mammography (FFDM). The thickness of dense tissue mapping to a pixel is determined by using a physical model of image acquisition. This model is based on the assumption that the breast

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

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

International Nuclear Information System (INIS)

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

2014-01-01

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

High-resolution digital dosimetric system for spatial characterization of radiation fields using a thermoluminescent CaF2:Dy crystal

International Nuclear Information System (INIS)

Atari, N.A.; Svensson, G.K.

1986-01-01

A high-resolution digital dosimetric system has been developed for the spatial characterization of radiation fields. The system comprises the following: 0.5-mm-thick, 25-mm-diam CaF2:Dy thermoluminescent crystal; intensified charge coupled device video camera; video cassette recorder; and a computerized image processing subsystem. The optically flat single crystal is used as a radiation imaging device and the subsequent thermally stimulated phosphorescence is viewed by the intensified camera for further processing and analysis. Parameters governing the performance characteristics of the system were measured. A spatial resolution limit of 31 +/- 2 microns (1 sigma) corresponding to 16 +/- 1 line pairs/mm measured at the 4% level of the modulation transfer function has been achieved. The full width at half maximum of the line spread function measured independently by the slit method or derived from the edge response function was found to be 69 +/- 4 microns (1 sigma). The high resolving power, speed of readout, good precision, wide dynamic range, and the large image storage capacity make the system suitable for the digital mapping of the relative distribution of absorbed doses for various small radiation fields and the edges of larger fields

High-resolution digital dosimetric system for spatial characterization of radiation fields using a thermoluminescent CaF2:Dy crystal

International Nuclear Information System (INIS)

Atari, N.A.; Svensson, G.K.

1986-01-01

A high-resolution digital dosimetric system has been developed for the spatial characterization of radiation fields. The system comprises the following: 0.5-mm-thick, 25-mm-diam CaF 2 :Dy thermoluminescent crystal; intensified charge coupled device video camera; video cassette recorder; and a computerized image processing subsystem. The optically flat single crystal is used as a radiation imaging device and the subsequent thermally stimulated phosphorescence is viewed by the intensified camera for further processing and analysis. Parameters governing the performance characteristics of the system were measured. A spatial resolution limit of 31 +- 2 μm (1sigma) corresponding to 16 +- 1 line pair/mm measured at the 4% level of the modulation transfer function has been achieved. The full width at half maximum of the line spread function measured independently by the slit method or derived from the edge response function was found to be 69 +- 4 μm (1sigma). The high resolving power, speed of readout, good precision, wide dynamic range, and the large image storage capacity make the system suitable for the digital mapping of the relative distribution of absorbed doses for various small radiation fields and the edges of larger fields

Genome-wide association study identifies multiple loci associated with both mammographic density and breast cancer risk

Science.gov (United States)

Lindström, Sara; Thompson, Deborah J.; Paterson, Andrew D.; Li, Jingmei; Gierach, Gretchen L.; Scott, Christopher; Stone, Jennifer; Douglas, Julie A.; dos-Santos-Silva, Isabel; Fernandez-Navarro, Pablo; Verghase, Jajini; Smith, Paula; Brown, Judith; Luben, Robert; Wareham, Nicholas J.; Loos, Ruth J.F.; Heit, John A.; Pankratz, V. Shane; Norman, Aaron; Goode, Ellen L.; Cunningham, Julie M.; deAndrade, Mariza; Vierkant, Robert A.; Czene, Kamila; Fasching, Peter A.; Baglietto, Laura; Southey, Melissa C.; Giles, Graham G.; Shah, Kaanan P.; Chan, Heang-Ping; Helvie, Mark A.; Beck, Andrew H.; Knoblauch, Nicholas W.; Hazra, Aditi; Hunter, David J.; Kraft, Peter; Pollan, Marina; Figueroa, Jonine D.; Couch, Fergus J.; Hopper, John L.; Hall, Per; Easton, Douglas F.; Boyd, Norman F.; Vachon, Celine M.; Tamimi, Rulla M.

2015-01-01

Mammographic density reflects the amount of stromal and epithelial tissues in relation to adipose tissue in the breast and is a strong risk factor for breast cancer. Here we report the results from meta-analysis of genome-wide association studies (GWAS) of three mammographic density phenotypes: dense area, non-dense area and percent density in up to 7,916 women in stage 1 and an additional 10,379 women in stage 2. We identify genome-wide significant (P<5×10−8) loci for dense area (AREG, ESR1, ZNF365, LSP1/TNNT3, IGF1, TMEM184B, SGSM3/MKL1), non-dense area (8p11.23) and percent density (PRDM6, 8p11.23, TMEM184B). Four of these regions are known breast cancer susceptibility loci, and four additional regions were found to be associated with breast cancer (P<0.05) in a large meta-analysis. These results provide further evidence of a shared genetic basis between mammographic density and breast cancer and illustrate the power of studying intermediate quantitative phenotypes to identify putative disease susceptibility loci. PMID:25342443

Screening for diabetic retinopathy in rural area using single-field, digital fundus images.

Science.gov (United States)

Ruamviboonsuk, Paisan; Wongcumchang, Nattapon; Surawongsin, Pattamaporn; Panyawatananukul, Ekchai; Tiensuwan, Montip

2005-02-01

To evaluate the practicability of using single-field, 2.3 million-pixel, digital fundus images for screening of diabetic retinopathy in rural areas. All diabetic patients who regularly attended the diabetic clinic at Kabcheang Community Hospital, located at 15 kilometers from the Thailand-Cambodia border, were appointed to the hospital for a 3-day diabetic retinopathy screening programme. The fundi of all patients were captured in single-field, 45 degrees, 2.3 million-pixel images using nonmydriatic digital fundus camera and then sent to a reading center in Bangkok. The fundi were also examined through dilated pupils by a retinal specialist at this hospital. The grading of diabetic retinopathy from two methods was compared for an exact agreement. The average duration of single digital fundus image capture was 2 minutes. The average file size of each image was 750 kilobytes. The average duration of single image transmission to a reading center in Bangkok via satellite was 3 minutes; via a conventional telephone line was 8 minutes. Of all 150 patients, 130 were assessed for an agreement between dilated fundus examination and digital fundus images in diagnosis of diabetic retinopathy. The exact agreement was 0.87, the weighted kappa statistics was 0.74. The sensitivity of digital fundus images in detecting diabetic retinopathy was 80%, the specificity was 96%. For diabetic macular edema the exact agreement was 0.97, the weighted kappa was 0.43, the sensitivity was 43%, and the specificity was 100%. The image capture of the nonmydriatic digital fundus camera is suitable for screening of diabetic retinopathy and single-field digital fundus images are potentially acceptable tools for the screening. The real-time image transmission via telephone lines to remote reading center, however, may not be practical for routine diabetic retinopathy screening in rural areas.

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

1-Million droplet array with wide-field fluorescence imaging for digital PCR.

Science.gov (United States)

Hatch, Andrew C; Fisher, Jeffrey S; Tovar, Armando R; Hsieh, Albert T; Lin, Robert; Pentoney, Stephen L; Yang, David L; Lee, Abraham P

2011-11-21

Digital droplet reactors are useful as chemical and biological containers to discretize reagents into picolitre or nanolitre volumes for analysis of single cells, organisms, or molecules. However, most DNA based assays require processing of samples on the order of tens of microlitres and contain as few as one to as many as millions of fragments to be detected. Presented in this work is a droplet microfluidic platform and fluorescence imaging setup designed to better meet the needs of the high-throughput and high-dynamic-range by integrating multiple high-throughput droplet processing schemes on the chip. The design is capable of generating over 1-million, monodisperse, 50 picolitre droplets in 2-7 minutes that then self-assemble into high density 3-dimensional sphere packing configurations in a large viewing chamber for visualization and analysis. This device then undergoes on-chip polymerase chain reaction (PCR) amplification and fluorescence detection to digitally quantify the sample's nucleic acid contents. Wide-field fluorescence images are captured using a low cost 21-megapixel digital camera and macro-lens with an 8-12 cm(2) field-of-view at 1× to 0.85× magnification, respectively. We demonstrate both end-point and real-time imaging ability to perform on-chip quantitative digital PCR analysis of the entire droplet array. Compared to previous work, this highly integrated design yields a 100-fold increase in the number of on-chip digitized reactors with simultaneous fluorescence imaging for digital PCR based assays.

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.

Small field electron beam dosimetry using MOSFET detector.

Science.gov (United States)

Amin, Md Nurul; Heaton, Robert; Norrlinger, Bern; Islam, Mohammad K

2010-10-04

The dosimetry of very small electron fields can be challenging due to relative shifts in percent depth-dose curves, including the location of dmax, and lack of lateral electronic equilibrium in an ion chamber when placed in the beam. Conventionally a small parallel plate chamber or film is utilized to perform small field electron beam dosimetry. Since modern radiotherapy departments are becoming filmless in favor of electronic imaging, an alternate and readily available clinical dosimeter needs to be explored. We have studied the performance of MOSFET as a relative dosimeter in small field electron beams. The reproducibility, linearity and sensitivity of a high-sensitivity microMOSFET were investigated for clinical electron beams. In addition, the percent depth doses, output factors and profiles have been measured in a water tank with MOSFET and compared with those measured by an ion chamber for a range of field sizes from 1 cm diameter to 10 cm × 10 cm for 6, 12, 16 and 20 MeV beams. Similar comparative measurements were also per-formed with MOSFET and films in solid water phantom. The MOSFET sensitivity was found to be practically constant over the range of field sizes investigated. The dose response was found to be linear and reproducible (within ± 1% for 100 cGy). An excellent agreement was observed among the central axis depth dose curves measured using MOSFET, film and ion chamber. The output factors measured with MOSFET for small fields agreed to within 3% with those measured by film dosimetry. Overall results indicate that MOSFET can be utilized to perform dosimetry for small field electron beam.

Digital Image Collections for Asian Religion and Art History in a Small-Sized Liberal Arts College

Directory of Open Access Journals (Sweden)

May Chang

2002-10-01

Full Text Available

頁次：6-15

small;">This paper reviews the establishment of a digital image library from 35mm slides to support faculty and student needs in a small-sized liberal arts college. The framework consists of central local resources, distributed faculty collections, and external resources. Standards and guidelines for digital preservation and access are also discussed. The pilot collections were multi-disciplinary resources in Middle East art and architecture and faculty slide collections in East Asian religions and Asian art history. Technical and management issues of integrating digital technology in the traditional slide library are also discussed.

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

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.

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.

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...

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.

A highly sensitive CMOS digital Hall sensor for low magnetic field applications.

Science.gov (United States)

Xu, Yue; Pan, Hong-Bin; He, Shu-Zhuan; Li, Li

2012-01-01

Integrated CMOS Hall sensors have been widely used to measure magnetic fields. However, they are difficult to work with in a low magnetic field environment due to their low sensitivity and large offset. This paper describes a highly sensitive digital Hall sensor fabricated in 0.18 μm high voltage CMOS technology for low field applications. The sensor consists of a switched cross-shaped Hall plate and a novel signal conditioner. It effectively eliminates offset and low frequency 1/f noise by applying a dynamic quadrature offset cancellation technique. The measured results show the optimal Hall plate achieves a high current related sensitivity of about 310 V/AT. The whole sensor has a remarkable ability to measure a minimum ± 2 mT magnetic field and output a digital Hall signal in a wide temperature range from -40 °C to 120 °C.

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

Comparison of breast percent density estimation from raw versus processed digital mammograms

Science.gov (United States)

Li, Diane; Gavenonis, Sara; Conant, Emily; Kontos, Despina

2011-03-01

We compared breast percent density (PD%) measures obtained from raw and post-processed digital mammographic (DM) images. Bilateral raw and post-processed medio-lateral oblique (MLO) images from 81 screening studies were retrospectively analyzed. Image acquisition was performed with a GE Healthcare DS full-field DM system. Image post-processing was performed using the PremiumViewTM algorithm (GE Healthcare). Area-based breast PD% was estimated by a radiologist using a semi-automated image thresholding technique (Cumulus, Univ. Toronto). Comparison of breast PD% between raw and post-processed DM images was performed using the Pearson correlation (r), linear regression, and Student's t-test. Intra-reader variability was assessed with a repeat read on the same data-set. Our results show that breast PD% measurements from raw and post-processed DM images have a high correlation (r=0.98, R2=0.95, p<0.001). Paired t-test comparison of breast PD% between the raw and the post-processed images showed a statistically significant difference equal to 1.2% (p = 0.006). Our results suggest that the relatively small magnitude of the absolute difference in PD% between raw and post-processed DM images is unlikely to be clinically significant in breast cancer risk stratification. Therefore, it may be feasible to use post-processed DM images for breast PD% estimation in clinical settings. Since most breast imaging clinics routinely use and store only the post-processed DM images, breast PD% estimation from post-processed data may accelerate the integration of breast density in breast cancer risk assessment models used in clinical practice.

Comparison of mammographic and sonographic findings in typical and atypical medullary carcinomas of the breast

International Nuclear Information System (INIS)

Yilmaz, E.; Lebe, B.; Balci, P.; Sal, S.; Canda, T.

2002-01-01

AIM: The aim of this study was to describe the contribution of mammographic and sonographic findings to the discrimination of typical and atypical histopathologic groups of medullary carcinomas of the breast. MATERIALS AND METHODS: Imaging findings were retrospectively assessed in 33 women with medullary carcinomas (15 typical medullary carcinomas and 18 atypical medullary carcinomas) identified during pre-operative mammography. Twenty-nine of these women also had ultrasound and these findings were reviewed. RESULTS: Mammography showed a well circumscribed mass in 10 of the 15 (67%) typical medullary carcinomas and in four of the 17 (24%) atypical medullary carcinomas (P < 0.02). One small tumour in a woman with atypical medullary carcinoma was missed on mammography and was shown only on sonography. Sonographically, an irregular margin surrounding the whole mass or part of it was seen in three out of 14 (21%) patients with typical medullary carcinoma and in nine out of 15 (60%) patients with atypical medullary carcinomas (P < 0.05). Posterior acoustic shadowing was more often observed in the typical medullary carcinoma group than in atypical medullary carcinoma and the difference was found to be statistically significant (P < 0.05). None of the other mammographic and sonographic findings were sufficiently characteristic to allow for a differentiation between two groups. CONCLUSION: When typical medullary carcinomas were compared with atypical medullary carcinomas according to imaging features, they tended to be well circumscribed masses on both mammography and sonography, and a posterior acoustic shadow was not found on sonography. However, the imaging findings in these two subgroups often resembled each other and histopathology will always be required to confirm the diagnosis. Yilmaz, E. et al. (2002)

Comparison of mammographic and sonographic findings in typical and atypical medullary carcinomas of the breast

Energy Technology Data Exchange (ETDEWEB)

Yilmaz, E.; Lebe, B.; Balci, P.; Sal, S.; Canda, T

2002-07-01

AIM: The aim of this study was to describe the contribution of mammographic and sonographic findings to the discrimination of typical and atypical histopathologic groups of medullary carcinomas of the breast. MATERIALS AND METHODS: Imaging findings were retrospectively assessed in 33 women with medullary carcinomas (15 typical medullary carcinomas and 18 atypical medullary carcinomas) identified during pre-operative mammography. Twenty-nine of these women also had ultrasound and these findings were reviewed. RESULTS: Mammography showed a well circumscribed mass in 10 of the 15 (67%) typical medullary carcinomas and in four of the 17 (24%) atypical medullary carcinomas (P < 0.02). One small tumour in a woman with atypical medullary carcinoma was missed on mammography and was shown only on sonography. Sonographically, an irregular margin surrounding the whole mass or part of it was seen in three out of 14 (21%) patients with typical medullary carcinoma and in nine out of 15 (60%) patients with atypical medullary carcinomas (P < 0.05). Posterior acoustic shadowing was more often observed in the typical medullary carcinoma group than in atypical medullary carcinoma and the difference was found to be statistically significant (P < 0.05). None of the other mammographic and sonographic findings were sufficiently characteristic to allow for a differentiation between two groups. CONCLUSION: When typical medullary carcinomas were compared with atypical medullary carcinomas according to imaging features, they tended to be well circumscribed masses on both mammography and sonography, and a posterior acoustic shadow was not found on sonography. However, the imaging findings in these two subgroups often resembled each other and histopathology will always be required to confirm the diagnosis. Yilmaz, E. et al. (2002)

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

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...

Micro-Structure Measurement and Imaging Based on Digital Holography

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyeong Suk; Jung, Hyun Chul; Chang, Ho Seob; Akhter, Naseem [Chosun University, Gwangju (Korea, Republic of); Kee, Chang Doo [Chonnam National University, Gwangju (Korea, Republic of)

2010-06-15

Advancements in the imaging and computing technology have opened the path to digital holography for non-destructive investigations of technical samples, material property measurement, vibration analysis, flow visualization and stress analysis in aerospace industry which has widened the application of digital holography in the above fields. In this paper, we demonstrate the non-destructive investigation and micro-structure measurement application of digital holography to the small particles and a biological sample. This paper gives a brief description of the digital holograms recorded with this system and illustratively demonstrated

Micro-Structure Measurement and Imaging Based on Digital Holography

International Nuclear Information System (INIS)

Kim, Kyeong Suk; Jung, Hyun Chul; Chang, Ho Seob; Akhter, Naseem; Kee, Chang Doo

2010-01-01

Advancements in the imaging and computing technology have opened the path to digital holography for non-destructive investigations of technical samples, material property measurement, vibration analysis, flow visualization and stress analysis in aerospace industry which has widened the application of digital holography in the above fields. In this paper, we demonstrate the non-destructive investigation and micro-structure measurement application of digital holography to the small particles and a biological sample. This paper gives a brief description of the digital holograms recorded with this system and illustratively demonstrated

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.

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.

Software Defined Radio (SDR) and Direct Digital Synthesizer (DDS) for NMR/MRI Instruments at Low-Field

Science.gov (United States)

Asfour, Aktham; Raoof, Kosai; Yonnet, Jean-Paul

2013-01-01

A proof-of-concept of the use of a fully digital radiofrequency (RF) electronics for the design of dedicated Nuclear Magnetic Resonance (NMR) systems at low-field (0.1 T) is presented. This digital electronics is based on the use of three key elements: a Direct Digital Synthesizer (DDS) for pulse generation, a Software Defined Radio (SDR) for a digital receiving of NMR signals and a Digital Signal Processor (DSP) for system control and for the generation of the gradient signals (pulse programmer). The SDR includes a direct analog-to-digital conversion and a Digital Down Conversion (digital quadrature demodulation, decimation filtering, processing gain…). The various aspects of the concept and of the realization are addressed with some details. These include both hardware design and software considerations. One of the underlying ideas is to enable such NMR systems to “enjoy” from existing advanced technology that have been realized in other research areas, especially in telecommunication domain. Another goal is to make these systems easy to build and replicate so as to help research groups in realizing dedicated NMR desktops for a large palette of new applications. We also would like to give readers an idea of the current trends in this field. The performances of the developed electronics are discussed throughout the paper. First FID (Free Induction Decay) signals are also presented. Some development perspectives of our work in the area of low-field NMR/MRI will be finally addressed. PMID:24287540

Software Defined Radio (SDR and Direct Digital Synthesizer (DDS for NMR/MRI Instruments at Low-Field

Directory of Open Access Journals (Sweden)

Aktham Asfour

2013-11-01

Full Text Available A proof-of-concept of the use of a fully digital radiofrequency (RF electronics for the design of dedicated Nuclear Magnetic Resonance (NMR systems at low-field (0.1 T is presented. This digital electronics is based on the use of three key elements: a Direct Digital Synthesizer (DDS for pulse generation, a Software Defined Radio (SDR for a digital receiving of NMR signals and a Digital Signal Processor (DSP for system control and for the generation of the gradient signals (pulse programmer. The SDR includes a direct analog-to-digital conversion and a Digital Down Conversion (digital quadrature demodulation, decimation filtering, processing gain…. The various aspects of the concept and of the realization are addressed with some details. These include both hardware design and software considerations. One of the underlying ideas is to enable such NMR systems to “enjoy” from existing advanced technology that have been realized in other research areas, especially in telecommunication domain. Another goal is to make these systems easy to build and replicate so as to help research groups in realizing dedicated NMR desktops for a large palette of new applications. We also would like to give readers an idea of the current trends in this field. The performances of the developed electronics are discussed throughout the paper. First FID (Free Induction Decay signals are also presented. Some development perspectives of our work in the area of low-field NMR/MRI will be finally addressed.

Effects of Different Compression Techniques on Diagnostic Accuracies of Breast Masses on Digitized Mammograms

International Nuclear Information System (INIS)

Zhigang Liang; Xiangying Du; Jiabin Liu; Yanhui Yang; Dongdong Rong; Xinyu Y ao; Kuncheng Li

2008-01-01

Background: The JPEG 2000 compression technique has recently been introduced into the medical imaging field. It is critical to understand the effects of this technique on the detection of breast masses on digitized images by human observers. Purpose: To evaluate whether lossless and lossy techniques affect the diagnostic results of malignant and benign breast masses on digitized mammograms. Material and Methods: A total of 90 screen-film mammograms including craniocaudal and lateral views obtained from 45 patients were selected by two non-observing radiologists. Of these, 22 cases were benign lesions and 23 cases were malignant. The mammographic films were digitized by a laser film digitizer, and compressed to three levels (lossless and lossy 20:1 and 40:1) using the JPEG 2000 wavelet-based image compression algorithm. Four radiologists with 10-12 years' experience in mammography interpreted the original and compressed images. The time interval was 3 weeks for each reading session. A five-point malignancy scale was used, with a score of 1 corresponding to definitely not a malignant mass, a score of 2 referring to not a malignant mass, a score of 3 meaning possibly a malignant mass, a score of 4 being probably a malignant mass, and a score of 5 interpreted as definitely a malignant mass. The radiologists' performance was evaluated using receiver operating characteristic analysis. Results: The average Az values for all radiologists decreased from 0.8933 for the original uncompressed images to 0.8299 for the images compressed at 40:1. This difference was not statistically significant. The detection accuracy of the original images was better than that of the compressed images, and the Az values decreased with increasing compression ratio. Conclusion: Digitized mammograms compressed at 40:1 could be used to substitute original images in the diagnosis of breast cancer

Design and development of a digital farmer field school. Experiences with a digital learning environment for cocoa production and certification in Sierra Leone

NARCIS (Netherlands)

Witteveen, Loes; Lie, Rico; Goris, Margriet; Ingram, Verina

2017-01-01

This article reports on the design and development of the Digital Farmer Field School (DFFS). The DFFS offers a tablet-based digital learning environment for farmers and extension agents for knowledge sharing and knowledge co-creation. It provides an alternative to conventional agricultural

Intravenous digital subtraction angiography of the lower limbs combined with field movement (2-field DSA)

International Nuclear Information System (INIS)

Fritschy, P.; Terrier, F.

1988-01-01

We evaluated a bolus-chase technique designed to reduce the volume of contrast material and to shorten examination time during intravenous digital subtraction angiography (IV-DSA) of the lower limbs. With this technique, after a single injection of contrast material, two contiguous fields can be sequentially imaged (two-field DAS) using a step translated X-ray tube. 67 patients with peripheral vascular disease were studied. All examinations provided diagnostic information, so that in no instance additional intra-arterial injections were required. With the two-field DSA only 3.49 injections were needed in the average for five fields examined in each patient, resulting in a 30% reduction of contrast agent used. (orig.) [de

Primary breast osteosarcoma mimicking calcified fibroadenoma on screening digital breast tomosynthesis mammogram

Directory of Open Access Journals (Sweden)

Debbie Lee Bennett, MD

2017-12-01

Full Text Available Primary breast osteosarcoma is a rare malignancy, with mostly case reports in the literature. The appearance of breast osteosarcoma on digital breast tomosynthesis imaging has not yet been described. A 69-year-old woman presents for routine screening mammography and is found to have a calcified mass in her right breast. Pattern of calcification appeared “sunburst” on digital breast tomosynthesis images. This mass was larger than on the previous year's mammogram, at which time it had been interpreted as a benign calcified fibroadenoma. The subsequent workup demonstrated the mass to reflect primary breast osteosarcoma. The patient's workup and treatment are detailed in this case. Primary breast osteosarcoma, although rare, should be included as a diagnostic consideration for breast masses with a sunburst pattern of calcifications, particularly when the mammographic appearance has changed.

Wide field of view common-path lateral-shearing digital holographic interference microscope.

Science.gov (United States)

Vora, Priyanka; Trivedi, Vismay; Mahajan, Swapnil; Patel, Nimit; Joglekar, Mugdha; Chhaniwal, Vani; Moradi, Ali-Reza; Javidi, Bahram; Anand, Arun

2017-12-01

Quantitative three-dimensional (3-D) imaging of living cells provides important information about the cell morphology and its time variation. Off-axis, digital holographic interference microscopy is an ideal tool for 3-D imaging, parameter extraction, and classification of living cells. Two-beam digital holographic microscopes, which are usually employed, provide high-quality 3-D images of micro-objects, albeit with lower temporal stability. Common-path digital holographic geometries, in which the reference beam is derived from the object beam, provide higher temporal stability along with high-quality 3-D images. Self-referencing geometry is the simplest of the common-path techniques, in which a portion of the object beam itself acts as the reference, leading to compact setups using fewer optical elements. However, it has reduced field of view, and the reference may contain object information. Here, we describe the development of a common-path digital holographic microscope, employing a shearing plate and converting one of the beams into a separate reference by employing a pin-hole. The setup is as compact as self-referencing geometry, while providing field of view as wide as that of a two-beam microscope. The microscope is tested by imaging and quantifying the morphology and dynamics of human erythrocytes. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

A fast continuous magnetic field measurement system based on digital signal processors

International Nuclear Information System (INIS)

Velev, G.V.; Carcagno, R.; DiMarco, J.; Kotelnikov, S.; Lamm, M.; Makulski, A.; Maroussov, V.; Nehring, R.; Nogiec, J.; Orris, D.; Poukhov, O.; Prakoshyn, F.; Schlabach, P.; Tompkins, J.C.

2005-01-01

In order to study dynamic effects in accelerator magnets, such as the decay of the magnetic field during the dwell at injection and the rapid so-called ''snapback'' during the first few seconds of the resumption of the energy ramp, a fast continuous harmonics measurement system was required. A new magnetic field measurement system, based on the use of digital signal processors (DSP) and Analog to Digital (A/D) converters, was developed and prototyped at Fermilab. This system uses Pentek 6102 16 bit A/D converters and the Pentek 4288 DSP board with the SHARC ADSP-2106 family digital signal processor. It was designed to acquire multiple channels of data with a wide dynamic range of input signals, which are typically generated by a rotating coil probe. Data acquisition is performed under a RTOS, whereas processing and visualization are performed under a host computer. Firmware code was developed for the DSP to perform fast continuous readout of the A/D FIFO memory and integration over specified intervals, synchronized to the probe's rotation in the magnetic field. C, C++ and Java code was written to control the data acquisition devices and to process a continuous stream of data. The paper summarizes the characteristics of the system and presents the results of initial tests and measurements

Standard guide for data fields for computerized transfer of digital radiological examination data

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This guide provides a listing and description of the fields that are recommended for inclusion in a digital radiological examination data base to facilitate the transfer of such data. This guide sets guidelines for the format of data fields for computerized transfer of digital image files obtained from radiographic, radioscopic, computed radiographic, or other radiological examination systems. The field listing includes those fields regarded as necessary for inclusion in the data base: (1) regardless of the radiological examination method (as indicated by Footnote C in Table 1), (2) for radioscopic examination (as indicated by Footnote E in Table 1), and (3) for radiographic examination (as indicated by Footnote D in Table 1). In addition, other optional fields are listed as a reminder of the types of information that may be useful for additional understanding of the data or applicable to a limited number of applications. 1.2 It is recognized that organizations may have in place an internal format for the...

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.

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)

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)

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.

FROST: an ASIC for digital mammography with synchrotron radiation

International Nuclear Information System (INIS)

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

2003-01-01

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

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

Development of a Motorized Digital Cone Penetrometer

OpenAIRE

Chung, Sun–Ok; Cho, Jin–Woong; Yamakawa, Takeo; 山川, 武夫

2012-01-01

Quantification and management of variability in soil strength, or soil compaction, is an important issue in countries such as Korea and Japan where typical field sizes are small, but tractor mounted on–the–go sensors that have been developed in USA and European countries are not practical. Therefore, hand–operated digital penetrometers have been widely used in Asian countries, but maintaining standard penetration rate and angle would be difficult. In this study, a motorized digital cone penet...

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

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.

Minimization of small bowel volume within treatment fields using customized small bowel displacement system (SBDS)

International Nuclear Information System (INIS)

Lim, D. H.; Huh, S. J.; Ahn, Y. C.; Kim, D. Y.; Wu, H. G.; Kim, M. K.; Choi, D. R.; Shin, K. H.

1997-01-01

Authors designed a customized Small Bowel Displacement System(SBDS) to displace the small bowel from the pelvic radiation fields and minimize treatment-related bowel morbidities. From August 1995 to May 1996, 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized styrofoam compression device which can displace the small bowel from the radiation fields and an individualized immobilization abdominal board for easy daily setup in prone position. After opacifying the small bowel with Barium, the patients were laid prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The areas of the small bowel included in the radiation fields with and without the SBDS were compared. Using the SBDS, the mean small bowel area was reduced by 59% on PA and 51% on LAT films (P=0.0001). In six patients (6/55, 11%), it was possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Only 15% (8/55) of patients treated with the SBDS manifested diarrhea requiring medication. The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and reduce the radiation therapy morbidities. Compliance with setup is excellent when the SBDS is used. (author)

Genotypes and haplotypes in the insulin-like growth factors, their receptors and binding proteins in relation to plasma metabolic levels and mammographic density

Directory of Open Access Journals (Sweden)

Chanock Stephen J

2010-03-01

Full Text Available Abstract Background Increased mammographic density is one of the strongest independent risk factors for breast cancer. It is believed that one third of breast cancers are derived from breasts with more than 50% density. Mammographic density is affected by age, BMI, parity, and genetic predisposition. It is also greatly influenced by hormonal and growth factor changes in a woman's life cycle, spanning from puberty through adult to menopause. Genetic variations in genes coding for hormones and growth factors involved in development of the breast are therefore of great interest. The associations between genetic polymorphisms in genes from the IGF pathway on mammographic density and circulating levels of IGF1, its binding protein IGFBP3, and their ratio in postmenopausal women are reported here. Methods Samples from 964 postmenopausal Norwegian women aged 55-71 years were collected as a part of the Tromsø Mammography and Breast Cancer Study. All samples were genotyped for 25 SNPs in IGF1, IGF2, IGF1R, IGF2R, IGFALS and IGFBP3 using Taqman (ABI. The main statistical analyses were conducted with the PROC HAPLOTYPE procedure within SAS/GENETICS™ (SAS 9.1.3. Results The haplotype analysis revealed six haploblocks within the studied genes. Of those, four had significant associations with circulating levels of IGF1 or IGFBP3 and/or mammographic density. One haplotype variant in the IGF1 gene was found to be associated with mammographic density. Within the IGF2 gene one haplotype variant was associated with levels of both IGF1 and IGFBP3. Two haplotype variants in the IGF2R were associated with the level of IGF1. Both variants of the IGFBP3 haplotype were associated with the IGFBP3 level and indicate regulation in cis. Conclusion Polymorphisms within the IGF1 gene and related genes were associated with plasma levels of IGF1, IGFBP3 and mammographic density in this study of postmenopausal women.

A Personal Digital Assistant (PDA) system for data acquisition during shoreline assessment field surveys

International Nuclear Information System (INIS)

Lamarche, A.; Owens, E.H.; Laflamme, A.; Laforest, S.; Clement, S.

2004-01-01

The Shoreline Cleanup Assessment Technique (SCAT) is a recognized method in North America to collect shoreline information and report observations on an oil spill. The long processing time required to analyze SCAT observations sometimes causes delays in oil spill response. Computerized systems have been developed to address this problem, but data entry of SCAT within such system involves much effort and is subject to potential errors. This paper described the development of a tool dedicated to the field capture of SCAT data on a Windows CE based Personal Digital Assistant (PDA). The system is compatible with both the SCAT methodology and Global Positioning System technology. A prototype of the system was tested during oil spills in Ontario and Nova Scotia. This paper described how the field data collection system was designed, developed and tested. Details of some user interfaces were provided to demonstrate how the large paper Shoreline Oiling Summary forms were made to fit on the small display screen of pocket-size devices. 8 refs., 1 tab., 12 figs

Facebook levels the playing field: Dyslexic students learning through digital literacies

Directory of Open Access Journals (Sweden)

Owen Barden

2014-02-01

Full Text Available Dyslexia has an ambivalent relationship with learning technology. Any potential gains may be nullified if the technology is perceived to exacerbate stigma. This paper examines the use of an ‘everyday’ technology, Facebook, by a small group of sixth form students labelled as dyslexic. ‘Levelling the playing field’ is a phrase the participants used often when discussing what they wanted from learning technology. Because dyslexia usually is defined in terms of significant difficulties with literacy, we might reasonably anticipate that the participants would see Facebook as stigmatising rather than levelling the playing field, because of the very public literacy events that it demands. However, the data indicate that far from shying away from Facebook because of fear of their difficulties with literacy being exposed, the participants enthusiastically embraced it. The students saw Facebook as a desirable presence in their education, one that supported inclusion. For them, levelling the playing field with Facebook had five dimensions: keeping up to date and meeting deadlines; increased control over learning; developing metacognitive awareness; greater control over literacy process and demands; and being experts and helpers. The findings perhaps challenge some assumptions about dyslexia, literacy and learning, and may be of interest to teachers working with dyslexic students, or researchers studying learning in digitally mediated social networks.

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...

a Survey on Topics, Researchers and Cultures in the Field of Digital Heritage

Science.gov (United States)

Münster, S.

2017-08-01

Digital heritage comprises a broad variety of approaches and topics and involves researchers from multiple disciplines. While the use of digital methods in the text-oriented disciplines dealing with cultural heritage is widely discussed and canonized, an up-to-date investigation on cultural heritage as a scholarly field is currently missing. The extended abstract is about a three-stage investigation on standards, publications, disciplinary cultures as well as scholars in the field of digital heritage, carried out in 2016 and 2017. It includes results of a workshop-based survey involving 44 researchers, 15 qualitative interviews as well as an online survey with nearly 1000 participants. As an overall finding, a community is driven by researchers from European countries and especially Italy with a background in humanities, dealing with topics of data acquisition, data management and visualization. Moreover, conference series are most relevant for a scientific discourse, and especially EU projects set pace as most important research endeavours.

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)

A fast continuous magnetic field measurement system based on digital signal processors

Energy Technology Data Exchange (ETDEWEB)

Velev, G.V.; Carcagno, R.; DiMarco, J.; Kotelnikov, S.; Lamm, M.; Makulski, A.; /Fermilab; Maroussov, V.; /Purdue U.; Nehring, R.; Nogiec, J.; Orris, D.; /Fermilab; Poukhov,; Prakoshyn, F.; /Dubna, JINR; Schlabach, P.; Tompkins, J.C.; /Fermilab

2005-09-01

In order to study dynamic effects in accelerator magnets, such as the decay of the magnetic field during the dwell at injection and the rapid so-called ''snapback'' during the first few seconds of the resumption of the energy ramp, a fast continuous harmonics measurement system was required. A new magnetic field measurement system, based on the use of digital signal processors (DSP) and Analog to Digital (A/D) converters, was developed and prototyped at Fermilab. This system uses Pentek 6102 16 bit A/D converters and the Pentek 4288 DSP board with the SHARC ADSP-2106 family digital signal processor. It was designed to acquire multiple channels of data with a wide dynamic range of input signals, which are typically generated by a rotating coil probe. Data acquisition is performed under a RTOS, whereas processing and visualization are performed under a host computer. Firmware code was developed for the DSP to perform fast continuous readout of the A/D FIFO memory and integration over specified intervals, synchronized to the probe's rotation in the magnetic field. C, C++ and Java code was written to control the data acquisition devices and to process a continuous stream of data. The paper summarizes the characteristics of the system and presents the results of initial tests and measurements.

Exploring Digital Health Use and Opinions of University Students: Field Survey Study.

Science.gov (United States)

Montagni, Ilaria; Cariou, Tanguy; Feuillet, Tiphaine; Langlois, Emmanuel; Tzourio, Christophe

2018-03-15

During university, students face some potentially serious health risks, and their lifestyle can have a direct effect on health and health behaviors later in life. Concurrently, university students are digital natives having easy access to the internet and new technologies. Digital health interventions offer promising new opportunities for health promotion, disease prevention, and care in this specific population. The description of the current use of and opinions on digital health among university students can inform future digital health strategies and interventions within university settings. The aim of this exploratory study was to report on university students' use and opinions regarding information and communication technologies for health and well-being, taking into account sociodemographic and self-rated general and mental health correlates. This field survey was conducted from March to April 2017. An informed consent form and a paper questionnaire were given to students aged 18 to 24 years in 4 university campuses in Bordeaux, France. The survey was formulated in 3 sections: (1) sociodemographic characteristics and self-rated general and mental health, (2) information about the use of digital health, and (3) opinions about digital health. Data were analyzed using descriptive statistics and tests of independence. A total of 59.8% (303/507 females) students completed the questionnaire. Concerning digital health use, 34.9% (174/498) had at least 1 health app mostly for physical activity (49.4%, 86/174) and general health monitoring (41.4%, 72/174,), but only 3.9% (20/507) of students had a wearable device. Almost all (94.8%, 450/476) had searched for Web-based health-related information at least once in the last 12 months. The most sought health-related topics were nutrition (68.1%, 324/476); pain and illnesses (64.5%, 307/476); and stress, anxiety, or depression (51.1%, 243/476). Although Wikipedia (79.7%, 357/448) and general health websites (349/448, 77

Exploring Digital Health Use and Opinions of University Students: Field Survey Study

Science.gov (United States)

Cariou, Tanguy; Feuillet, Tiphaine; Langlois, Emmanuel; Tzourio, Christophe

2018-01-01

Background During university, students face some potentially serious health risks, and their lifestyle can have a direct effect on health and health behaviors later in life. Concurrently, university students are digital natives having easy access to the internet and new technologies. Digital health interventions offer promising new opportunities for health promotion, disease prevention, and care in this specific population. The description of the current use of and opinions on digital health among university students can inform future digital health strategies and interventions within university settings. Objective The aim of this exploratory study was to report on university students’ use and opinions regarding information and communication technologies for health and well-being, taking into account sociodemographic and self-rated general and mental health correlates. Methods This field survey was conducted from March to April 2017. An informed consent form and a paper questionnaire were given to students aged 18 to 24 years in 4 university campuses in Bordeaux, France. The survey was formulated in 3 sections: (1) sociodemographic characteristics and self-rated general and mental health, (2) information about the use of digital health, and (3) opinions about digital health. Data were analyzed using descriptive statistics and tests of independence. Results A total of 59.8% (303/507 females) students completed the questionnaire. Concerning digital health use, 34.9% (174/498) had at least 1 health app mostly for physical activity (49.4%, 86/174) and general health monitoring (41.4%, 72/174,), but only 3.9% (20/507) of students had a wearable device. Almost all (94.8%, 450/476) had searched for Web-based health-related information at least once in the last 12 months. The most sought health-related topics were nutrition (68.1%, 324/476); pain and illnesses (64.5%, 307/476); and stress, anxiety, or depression (51.1%, 243/476). Although Wikipedia (79.7%, 357/448) and

Population-based mammography screening: comparison of screen-film and full-field digital mammography with soft-copy reading--Oslo I study.

Science.gov (United States)

Skaane, Per; Young, Kari; Skjennald, Arnulf

2003-12-01

To compare screen-film and full-field digital mammography with soft-copy reading in a population-based screening program. Full-field digital and screen-film mammography were performed in 3,683 women aged 50-69 years. Two standard views of each breast were acquired with each modality. Images underwent independent double reading with use of a five-point rating scale for probability of cancer. Recall rates and positive predictive values were calculated. Cancer detection rates determined with both modalities were compared by using the McNemar test for paired proportions. Retrospective side-by-side analysis for conspicuity of cancers was performed by an external independent radiologist group with experience in both modalities. In 3,683 cases, 31 cancers were detected. Screen-film mammography depicted 28 (0.76%) malignancies, and full-field digital mammography depicted 23 (0.62%) malignancies. The difference between cancer detection rates was not significant (P =.23). The recall rate for full-field digital mammography (4.6%; 168 of 3,683 cases) was slightly higher than that for screen-film mammography (3.5%; 128 of 3,683 cases). The positive predictive value based on needle biopsy results was 46% for screen-film mammography and 39% for full-field digital mammography. Side-by-side image comparison for cancer conspicuity led to classification of 19 cancers as equal for probability of malignancy, six cancers as slightly better demonstrated at screen-film mammography, and six cancers as slightly better demonstrated at full-field digital mammography. There was no statistically significant difference in cancer detection rate between screen-film and full-field digital mammography. Cancer conspicuity was equal with both modalities. Full-field digital mammography with soft-copy reading is comparable to screen-film mammography in population-based screening.

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.

Sub-millimetre DOI detector based on monolithic LYSO and digital SiPM for a dedicated small-animal PET system

International Nuclear Information System (INIS)

Marcinkowski, Radosław; Mollet, Pieter; Van Holen, Roel; Vandenberghe, Stefaan

2016-01-01

The mouse model is widely used in a vast range of biomedical and preclinical studies. Thanks to the ability to detect and quantify biological processes at the molecular level in vivo, PET has become a well-established tool in these investigations. However, the need to visualize and quantify radiopharmaceuticals in anatomic structures of millimetre or less requires good spatial resolution and sensitivity from small-animal PET imaging systems. In previous work we have presented a proof-of-concept of a dedicated high-resolution small-animal PET scanner based on thin monolithic scintillator crystals and Digital Photon Counter photosensor. The combination of thin monolithic crystals and MLE positioning algorithm resulted in an excellent spatial resolution of 0.7 mm uniform in the entire field of view (FOV). However, the limitation of the scanner was its low sensitivity due to small thickness of the lutetium-yttrium oxyorthosilicate (LYSO) crystals (2 mm). Here we present an improved detector design for a small-animal PET system that simultaneously achieves higher sensitivity and sustains a sub-millimetre spatial resolution. The proposed detector consists of a 5 mm thick monolithic LYSO crystal optically coupled to a Digital Photon Counter. Mean nearest neighbour (MNN) positioning combined with depth of interaction (DOI) decoding was employed to achieve sub-millimetre spatial resolution. To evaluate detector performance the intrinsic spatial resolution, energy resolution and coincidence resolving time (CRT) were measured. The average intrinsic spatial resolution of the detector was 0.60 mm full-width-at-half-maximum (FWHM). A DOI resolution of 1.66 mm was achieved. The energy resolution was 23% FWHM at 511 keV and CRT of 529 ps were measured. The improved detector design overcomes the sensitivity limitation of the previous design by increasing the nominal sensitivity of the detector block and retains an excellent intrinsic spatial resolution. (paper)

11-gauge vacuum assisted directional biopsy of breast calcifications, using upright stereotactic guidance

International Nuclear Information System (INIS)

Nisbet, A.P.; Borthwick-Clarke, A.; Scott, N.

2000-01-01

To assess the use of a prototype vacuum assisted biopsy device on a standard upright mammography unit, using a slightly modified digital stereotactic add-on component. A group comprised of 42 sequential patients, who had been recalled from an asymptomatic mammographic screening programme, were studied. All 42 were recalled for assessment of small clusters of microcalcification, graded as indeterminate. Group 1 (21 patients) were biopsied using 14-gauge automated large core needle biopsy. Group 2 (21 patients) were biopsied using 11-gauge vacuum assisted biopsy. Both groups had mammographic guidance on the same upright mammographic unit (Siemens 3000), with Opdima Digital Stereotactic add-on. A total of 86% of specimen radiographs in Group 2 patients (vacuum assisted biopsy) showed successful sampling of the calcifications, compared to 62% of Group 1 patients (14-gauge automated large core biopsies). This study shows that vacuum assisted biopsy is possible using upright stereotactic mammography units. The technique shows promise as a biopsy tool, offering larger cores compared to 14-gauge automated large core biopsy, while requiring less space and lower purchase price compared to dedicated prone biopsy tables. The technique also offers access to biopsy in patients with posterior lesions and for patients who cannot tolerate prone positioning

Multimodal breast cancer imaging using coregistered dynamic diffuse optical tomography and digital breast tomosynthesis

Science.gov (United States)

Zimmermann, Bernhard B.; Deng, Bin; Singh, Bhawana; Martino, Mark; Selb, Juliette; Fang, Qianqian; Sajjadi, Amir Y.; Cormier, Jayne; Moore, Richard H.; Kopans, Daniel B.; Boas, David A.; Saksena, Mansi A.; Carp, Stefan A.

2017-04-01

Diffuse optical tomography (DOT) is emerging as a noninvasive functional imaging method for breast cancer diagnosis and neoadjuvant chemotherapy monitoring. In particular, the multimodal approach of combining DOT with x-ray digital breast tomosynthesis (DBT) is especially synergistic as DBT prior information can be used to enhance the DOT reconstruction. DOT, in turn, provides a functional information overlay onto the mammographic images, increasing sensitivity and specificity to cancer pathology. We describe a dynamic DOT apparatus designed for tight integration with commercial DBT scanners and providing a fast (up to 1 Hz) image acquisition rate to enable tracking hemodynamic changes induced by the mammographic breast compression. The system integrates 96 continuous-wave and 24 frequency-domain source locations as well as 32 continuous wave and 20 frequency-domain detection locations into low-profile plastic plates that can easily mate to the DBT compression paddle and x-ray detector cover, respectively. We demonstrate system performance using static and dynamic tissue-like phantoms as well as in vivo images acquired from the pool of patients recalled for breast biopsies at the Massachusetts General Hospital Breast Imaging Division.

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.

Tumor characteristics and family history in relation to mammographic density and breast cancer: The French E3N cohort.

Science.gov (United States)

Maskarinec, Gertraud; Dartois, Laureen; Delaloge, Suzette; Hopper, John; Clavel-Chapelon, Françoise; Baglietto, Laura

2017-08-01

Mammographic density is a known heritable risk factor for breast cancer, but reports how tumor characteristics and family history may modify this association are inconsistent. Dense and total breast areas were assessed using Cumulus™ from pre-diagnostic mammograms for 820 invasive breast cancer cases and 820 matched controls nested within the French E3N cohort study. To allow comparisons across models, percent mammographic density (PMD) was standardized to the distribution of the controls. Odds ratios (OR) and 95% confidence intervals (CI) of breast cancer risk for mammographic density were estimated by conditional logistic regression while adjusting for age and body mass index. Heterogeneity according to tumor characteristic and family history was assessed using stratified analyses. Overall, the OR per 1 SD for PMD was 1.50 (95% CI, 1.33-1.69). No evidence for significant heterogeneity by tumor size, lymph node status, grade, and hormone receptor status (estrogen, progesterone, and HER2) was detected. However, the association of PMD was stronger for women reporting a family history of breast cancer (OR 1SD =2.25; 95% CI, 1.67-3.04) than in women reporting none (OR 1SD =1.41; 95% CI, 1.24-1.60; p heterogeneity =0.002). Similarly, effect modification by FHBC was observed using categories of PMD (p heterogeneity =0.02) with respective ORs of 15.16 (95% CI, 4.23-54.28) vs. 3.14 (95% CI, 1.89-5.22) for ≥50% vs. breast cancer risk with a family history supports the hypothesis of shared genetic factors responsible for familial aggregation of breast cancer and the heritable component of mammographic density. Copyright © 2017 Elsevier Ltd. All rights reserved.

SU-E-T-471: Small Field Jaw/MLC Reference Data

International Nuclear Information System (INIS)

Kerns, J; Alvarez, P; Followill, D; Lowenstein, J; Molineu, A; Summers, P; Kry, S

2014-01-01

Purpose: In recent years the need for small field data of MLCs has increased due to the use of intensity-modulated radiation (IMRT), but moreover the use of stereotactic body radiation (SBRT) has increased, which uses not simply small field sizes, but small jaw and field sizes together. Having reference data for these small fields that is reliable would be invaluable to the physics community. Our study has gathered these values and the data distributions from the Radiological Physics Center's (RPC) site visits between 1990 and the present. Methods: For all measurements, the RPC used a 25 × 25 × 25cm water phantom placed at 100cm SSD. All measurements were made with an Exradin A16 cylindrical ion chamber at an effective depth of 10 cm. A total of 42 Varian machine measurements were used to compose the data for a 6 MV beam and 5 TrueBeam 6 MV flattening filter free (FFF) beams were used for FFF data. Results: Jaw/MLC fields were measured for both 6 MV and 6 MF FFF beams with the jaws and MLCs both at the following field sizes: 6×6, 4×4, 3×3, and 2×2cm. Measurements were normalized to the 10×10 field readings (defined by the jaws and MLC). Spread in the data was minimal and demonstrates a high level of accuracy of acquired data. Conclusion: Small field Jaw/MLC reference data for Varian 6MV and 6 MV FFF beams has been analyzed and presented here, composed of the aggregation of numerous RPC site visits. Obtaining reliable small field data remains difficult, however the RPC has collected high fidelity small field Jaw/MLC data. The data are presented as a reference along with their distributions, in such a way that the physicist can act based upon their own desired agreement with the reference data

Digital Signal Processing in Beam Instrumentation Latest Trends and Typical Applications

CERN Document Server

Angoletta, Maria Elena

2003-01-01

The last decade has seen major improvements in digital hardware, algortithms and software, which have trickled down to the Beam Instrumentation (BI) area. An advantageous transition is taking place towards systems with an ever-stronger digital presence. Digital systems are assembled by means of a rather small number of basic building blocks, with improved speed, precision, signal-to-noise ratio, dynamic range, flexibility, and accompanied by a range of powerful and user-friendly development tools. The paper reviews current digital BI trends, including using Digital Signal Processors, Field Programmable Gate Arrays, Digital Receivers and General Purpose Processors as well as some useful processing algorithms. Selected digital applications are illustrated on control/feedback and beam diagnostics.

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)

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.

Radiologic-pathologic correlation of the mammographic findings retrospectively detected in inflammatory breast cancer. Usefulness in clinical practice

International Nuclear Information System (INIS)

Caumo, F.; Manfrin, E.; Bonetti, F.; Pinali, L.; Procacci, C.

2002-01-01

Background. The aim of this study was to describe the clinical, mammographical and pathological characteristics of inflammatory carcinoma. Patients and methods. Clinical, mammographical and histological sections of twenty-two women (age range 28-60 years) were reviewed. The examinations had been performed over a period of four years. Results. The clinical findings were: erythema, edema, thickening of the skin and breast heat in ten patients; palpable mass in nine patients; nipple discharge in one patient; absent in two patients. Pathological findings were: tumor emboli in the dermal lymphatics in eight patients; tumor emboli in the vessels in ten patients; tumor emboli both in the dermal lymphatics and in the vessels in four patients. The radiologic findings were: skin thickening, trabecular thickening and blurring of structure in ten patients (common presentation); mass in nine patients; malignant-type calcifications in two patients (uncommon presentation); absent in one patient. The follow-up examination (eighteen months) detected that only one patient with common presentation of inflammatory carcinoma had no local or systemic recurrence against eight patients with uncommon presentation. Conclusions. The clinical and mammographical aspects, which suggest the presence of an inflammatory carcinoma, occur only in 45.4% of the patients. The radiological aspect seems to correlate with the different prognosis of the tumour, resulting in a better prognosis in those with an uncommon aspect. (author)

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...

An Inverse MOOC Model: Small Virtual Field Geology Classes with Many Teachers (Invited)

Science.gov (United States)

De Paor, D. G.; Whitmeyer, S. J.; Bentley, C.

2013-12-01

In the Massive Open Online Courses (MOOCs) mode of instruction, one or a small group of collaborating instructors lecture online to a large (often extremely large) number of students. We are experimenting with an inverse concept: an online classroom in which a small group of collaborating students are taught by dozens of collaborating instructors. This experiment is part of a new NSF TUES Type 3 project titled 'Google Earth for Onsite and Distance Education (GEODE).' Among the goals of the project are the development of an online course called the 'Grand Tour.' We are inviting dozens of colleagues to record virtual field trips (VFTs) and upload them to Google Earth. Students enrolled in the course will be assigned to a small group and tasked with a research project--for example to write a report on foreland thrust belts. They will select a small subset of available VFTs to follow and will be scaffolded by virtual specimens, emergent cross sections, analytical simulations (virtual tricorders), and a game style environment. Instant feedback based on auto-logging will enable adaptive learning. The design is suited to both onsite and distance education and will facilitate access to iconic geologic sites around the world to persons with mobility constraints. We invite input from the community to help guide the design phase of this project. Prototypes of the above-listed learning resources have already been developed and are freely available at http://www.DigitalPlanet.org.

Digital field mapping for stimulating Secondary School students in the recognition of geological features and landforms

Science.gov (United States)

Giardino, Marco; Magagna, Alessandra; Ferrero, Elena; Perrone, Gianluigi

2015-04-01

Digital field mapping has certainly provided geoscientists with the opportunity to map and gather data in the field directly using digital tools and software rather than using paper maps, notebooks and analogue devices and then subsequently transferring the data to a digital format for subsequent analysis. But, the same opportunity has to be recognized for Geoscience education, as well as for stimulating and helping students in the recognition of landforms and interpretation of the geological and geomorphological components of a landscape. More, an early exposure to mapping during school and prior to university can optimise the ability to "read" and identify uncertainty in 3d models. During 2014, about 200 Secondary School students (aged 12-15) of the Piedmont region (NW Italy) participated in a research program involving the use of mobile devices (smartphone and tablet) in the field. Students, divided in groups, used the application Trimble Outdoors Navigators for tracking a geological trail in the Sangone Valley and for taking georeferenced pictures and notes. Back to school, students downloaded the digital data in a .kml file for the visualization on Google Earth. This allowed them: to compare the hand tracked trail on a paper map with the digital trail, and to discuss about the functioning and the precision of the tools; to overlap a digital/semitransparent version of the 2D paper map (a Regional Technical Map) used during the field trip on the 2.5D landscape of Google Earth, as to help them in the interpretation of conventional symbols such as contour lines; to perceive the landforms seen during the field trip as a part of a more complex Pleistocene glacial landscape; to understand the classical and innovative contributions from different geoscientific disciplines to the generation of a 3D structural geological model of the Rivoli-Avigliana Morainic Amphitheatre. In 2013 and 2014, some other pilot projects have been carried out in different areas of the

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.)

Digital approximation to extended depth of field in no telecentric imaging systems

International Nuclear Information System (INIS)

Meneses, J E; Contreras, C R

2011-01-01

A method used to digitally extend the depth of field of an imaging system consists to move the object of study along the optical axis of the system and different images will contain different areas that are sharp; those images are stored and processed digitally to obtain a fused image, in that image will be sharp all regions of the object. The implementation of this method, although widely used, imposes certain experimental conditions that should be evaluated for to study the degree of validity of the image final obtained. An experimental condition is related with the conservation of the geometric magnification factor when there is a relative movement between the object and the observation system; this implies that the system must be telecentric, which leads to a reduction of the observation field and the use of expensive systems if the application includes microscopic observation. This paper presents a technique that makes possible to extend depth of filed of an imaging system non telecentric; this system is used to realize applications in Optical Metrology with systems that have great observation field.

Electromagnetic fields in small systems from a multiphase transport model

Science.gov (United States)

Zhao, Xin-Li; Ma, Yu-Gang; Ma, Guo-Liang

2018-02-01

We calculate the electromagnetic fields generated in small systems by using a multiphase transport (AMPT) model. Compared to A +A collisions, we find that the absolute electric and magnetic fields are not small in p +Au and d +Au collisions at energies available at the BNL Relativistic Heavy Ion Collider and in p +Pb collisions at energies available at the CERN Large Hadron Collider. We study the centrality dependencies and the spatial distributions of electromagnetic fields. We further investigate the azimuthal fluctuations of the magnetic field and its correlation with the fluctuating geometry using event-by-event simulations. We find that the azimuthal correlation 〈" close="〉cos(ϕα+ϕβ-2 ΨRP)〉">cos2 (ΨB-Ψ2) between the magnetic field direction and the second-harmonic participant plane is almost zero in small systems with high multiplicities, but not in those with low multiplicities. This indicates that the charge azimuthal correlation is not a valid probe to study the chiral magnetic effect (CME) in small systems with high multiplicities. However, we suggest searching for possible CME effects in small systems with low multiplicities.

Development of small and inexpensive digital data acquisition systems using a microcontroller-based approach.

Science.gov (United States)

Naivar, Mark A; Wilder, Mark E; Habbersett, Robert C; Woods, Travis A; Sebba, David S; Nolan, John P; Graves, Steven W

2009-12-01

Fully digital data acquisition systems for use in flow cytometry provide excellent flexibility and precision. Here, we demonstrate the development of a low cost, small, and low power digital flow cytometry data acquisition system using a single microcontroller chip with an integrated analog to digital converter (ADC). Our demonstration system uses a commercially available evaluation board making the system simple to integrate into a flow cytometer. We have evaluated this system using calibration microspheres analyzed on commercial, slow-flow, and CCD-based flow cytometers. In our evaluations, our demonstration data system clearly resolves all eight peaks of a Rainbow microsphere set on both a slow-flow flow cytometer and a retrofitted BD FACScalibur, which indicates it has the sensitivity and resolution required for most flow cytometry applications. It is also capable of millisecond time resolution, full waveform collection, and selective triggering of data collection from a CCD camera. The capability of our demonstration system suggests that the use of microcontrollers for flow cytometry digital data-acquisition will be increasingly valuable for extending the life of older cytometers and provides a compelling data-system design approach for low-cost, portable flow cytometers.

Development of small and inexpensive digital data acquisition systems using a microcontroller-based approach†

Science.gov (United States)

Naivar, Mark A.; Wilder, Mark E.; Habbersett, Robert C.; Woods, Travis A.; Sebba, David S.; Nolan, John P.; Graves, Steven W.

2014-01-01

Fully digital data acquisition systems for use in flow cytometry provide excellent flexibility and precision. Here, we demonstrate the development of a low cost, small, and low power digital flow cytometry data acquisition system using a single microcontroller chip with an integrated analog to digital converter (ADC). Our demonstration system uses a commercially available evaluation board making the system simple to integrate into a flow cytometer. We have evaluated this system using calibration microspheres analyzed on commercial, slow-flow, and CCD based flow cytometers. In our evaluations, our demonstration data system clearly resolves all eight peaks of a Rainbow microsphere set on both a slow-flow flow cytometer and a retrofitted BD FACScalibur, which indicates it has the sensitivity and resolution required for most flow cytometry applications. It is also capable of millisecond time resolution, full waveform collection, and selective triggering of data collection from a CCD camera. The capability of our demonstration system suggests that the use of microcontrollers for flow cytometry digital data-acquisition will be increasingly valuable for extending the life of older cytometers and provides a compelling data-system design approach for low-cost, portable flow cytometers. PMID:19852060

Quantification of breast arterial calcification using full field digital mammography

International Nuclear Information System (INIS)

Molloi, Sabee; Xu Tong; Ducote, Justin; Iribarren, Carlos

2008-01-01

Breast arterial calcification is commonly detected on some mammograms. Previous studies indicate that breast arterial calcification is evidence of general atherosclerotic vascular disease and it may be a useful marker of coronary artery disease. It can potentially be a useful tool for assessment of coronary artery disease in women since mammography is widely used as a screening tool for early detection of breast cancer. However, there are currently no available techniques for quantification of calcium mass using mammography. The purpose of this study was to determine whether it is possible to quantify breast arterial calcium mass using standard digital mammography. An anthropomorphic breast phantom along with a vessel calcification phantom was imaged using a full field digital mammography system. Densitometry was used to quantify calcium mass. A calcium calibration measurement was performed at each phantom thickness and beam energy. The known (K) and measured (M) calcium mass on 5 and 9 cm thickness phantoms were related by M=0.964K-0.288 mg (r=0.997 and SEE=0.878 mg) and M=1.004K+0.324 mg (r=0.994 and SEE=1.32 mg), respectively. The results indicate that accurate calcium mass measurements can be made without correction for scatter glare as long as careful calcium calibration is made for each breast thickness. The results also indicate that composition variations and differences of approximately 1 cm between calibration phantom and breast thickness introduce only minimal error in calcium measurement. The uncertainty in magnification is expected to cause up to 5% and 15% error in calcium mass for 5 and 9 cm breast thicknesses, respectively. In conclusion, a densitometry technique for quantification of breast arterial calcium mass was validated using standard full field digital mammography. The results demonstrated the feasibility and potential utility of the densitometry technique for accurate quantification of breast arterial calcium mass using standard digital

A 3D technique for simulation of irregular electron treatment fields using a digital camera

International Nuclear Information System (INIS)

Bassalow, Roustem; Sidhu, Narinder P.

2003-01-01

Cerrobend inserts, which define electron field apertures, are manufactured at our institution using perspex templates. Contours are reproduced manually on these templates at the simulator from the field outlines drawn on the skin or mask of a patient. A previously reported technique for simulation of electron treatment fields uses a digital camera to eliminate the need for such templates. However, avoidance of the image distortions introduced by non-flat surfaces on which the electron field outlines were drawn could only be achieved by limiting the application of this technique to surfaces which were flat or near flat. We present a technique that employs a digital camera and allows simulation of electron treatment fields contoured on an anatomical surface of an arbitrary three-dimensional (3D) shape, such as that of the neck, extremities, face, or breast. The procedure is fast, accurate, and easy to perform

Digital Materialisms: Frameworks for Digital Media Studies

OpenAIRE

Casemajor, Nathalie

2015-01-01

Since the 1980s, digital materialism has received increasing interest in the field of media studies. Materialism as a theoretical paradigm assumes that all things in the world are tied to physical processes and matter. Yet within digital media studies, the understanding of what should be the core object of a materialist analysis is debated. This paper proposes to untangle some of the principal theoretical propositions that compose the field of digital materialism. It outlines six frameworks t...

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.

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

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...

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.

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,

The New Digital Divide For Digital BioMarkers.

Science.gov (United States)

Torous, John; Rodriguez, Jorge; Powell, Adam

2017-09-01

As smartphone and sensors continue to become more ubiquitous across the world, digital biomarkers have emerged as a scalable and practical tool to explore disease states and advance health. But as the digital divide of access and ownership begins to fade, a new digital divide is emerging. Who are the types of people that own smartphones or smart watches, who are the types of people that download health apps or partake in digital biomarker studies, and who are the types of people that are actually active with digital biomarkers apps and sensors - the people providing the high quality and longitudinal data that this field is being founded upon? Understanding the people behind digital biomarkers, the very people this emerging field aims to help, may actually be the real challenge as well as opportunity for digital biomarkers.

Possible effects of insulin-like growth factor-I, IGF-binding protein-3 and IGF-1/IGFBP-3 molar ratio on mammographic density: a cross-sectional study.

Science.gov (United States)

Meggiorini, M L; Cipolla, V; Borgoni, G; Nofroni, I; Pala, A; de Felice, C

2012-01-01

The purpose of this study was to examine the possible effects of IGF-1, IGFBP-3 and IGF-1/IGFBP-3 molar ratio on mammographic density and assess whether this relationship was similar in subgroups of pre- and postmenopausal women. A group of 341 Italian women of childbearing age or naturally postmenopausal who had performed mammographic examination at the section of radiology of our department a maximum three months prior to recruitment were enrolled. A blood sample was drawn for determination of IGF-1, IGFBP-3 levels and IGF-1/IGFBP-3 molar ratio was calculated. On the basis of recent mammograms the women were divided into two groups: dense breast (DB) and non-dense breast (NDB). To assess the association between mammographic density and IGF-1, IGFBP-3 and Molar ratio Student's t-test was employed before and after stratified by menopausal status. The analysis of the relationship between mammographic density and plasma levels of IGF-1, IGFBP-3 and IGF-1/IGFBP-3 molar ratio showed that IGF-1 levels and molar ratio varied in the two groups resulting in higher mean values in the DB group whereas IGFBP-3 showed similar values in both groups (DB and NDB). After stratification of the study population by menopausal status, no association was found. Our study provides strong evidence of a crude association between breast density, and plasma levels of IGF-1 and molar ratio. IGF-1 and molar ratio might increase mammographic density and thus the risk of developing breast cancer.

Breast Cancer Risk Estimation Using Parenchymal Texture Analysis in Digital Breast Tomosynthesis

International Nuclear Information System (INIS)

Ikejimba, Lynda C.; Kontos, Despina; Maidment, Andrew D. A.

2010-01-01

Mammographic parenchymal texture has been shown to correlate with genetic markers of developing breast cancer. Digital breast tomosynthesis (DBT) is a novel x-ray imaging technique in which tomographic images of the breast are reconstructed from multiple source projections acquired at different angles of the x-ray tube. Compared to digital mammography (DM), DBT eliminates breast tissue overlap, offering superior parenchymal tissue visualization. We hypothesize that texture analysis in DBT could potentially provide a better assessment of parenchymal texture and ultimately result in more accurate assessment of breast cancer risk. As a first step towards validating this hypothesis, we investigated the association between DBT parenchymal texture and breast percent density (PD), a known breast cancer risk factor, and compared it to DM. Bilateral DBT and DM images from 71 women participating in a breast cancer screening trial were analyzed. Filtered-backprojection was used to reconstruct DBT tomographic planes in 1 mm increments with 0.22 mm in-plane resolution. Corresponding DM images were acquired at 0.1 mm pixel resolution. Retroareolar regions of interest (ROIs) equivalent to 2.5 cm 3 were segmented from the DBT images and corresponding 2.5 cm 2 ROIs were segmented from the DM images. Breast PD was mammographically estimated using the Cumulus scale. Overall, DBT texture features demonstrated a stronger correlation than DM to PD. The Pearson correlation coefficients for DBT were r = 0.40 (p 2 = 0.39) compared to DM (R 2 = 0.33). We attribute these observations to the superior parenchymal tissue visualization in DBT. Our study is the first to perform DBT texture analysis in a screening population of women, showing that DBT could potentially provide better breast cancer risk assessment in the future.

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

International Nuclear Information System (INIS)

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

2013-01-01

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

Simple concept for a wide-field lensless digital holographic microscope using a laser diode

Directory of Open Access Journals (Sweden)

Adinda-Ougba A.

2015-09-01

Full Text Available Wide-field, lensless digital holographic microscopy is a new microscopic imaging technique for telemedicine and for resource limited setting [1]. In this contribution we propose a very simple wide-field lensless digital holographic microscope using a laser diode. It is based on in-line digital holography which is capable to provide amplitude and phase images of a sample resulting from numerical reconstruction. The numerical reconstruction consists of the angular spectrum propagation method together with a phase retrieval algorithm. Amplitude and phase images of the sample with a resolution of ∽2 µm and with ∽24 mm2 field of view are obtained. We evaluate our setup by imaging first the 1951 USAF resolution test chart to verify the resolution. Second, we record holograms of blood smear and diatoms. The individual specimen can be easily identified after the numerical reconstruction. Our system is a very simple, compact and low-cost possibility of realizing a microscope capable of imaging biological samples. The availability of the phase provide topographic information of the sample extending the application of this system to be not only for biological sample but also for transparent microstructure. It is suitable for fault detection, shape and roughness measurements of these structures.

Digital Risk Inventory and Evaluation (RIE) : a Dutch approach offering valuable support for small business owners

NARCIS (Netherlands)

Meeuwsen, J.M.

2008-01-01

The Dutch Working Conditions Act requires employers to perform a Risk Inventory and Evaluation (RIE). Until recently, small business owners (SMEs) in particular were unhappy about this rather time-consuming obligation. However, the introduction of digital RIE instruments disseminated through the web

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

Digital cytology: current state of the art and prospects for the future.

Science.gov (United States)

Wilbur, David C

2011-01-01

The growth of digital methods in pathology is accelerating. Digital images can be used for a variety of applications in cytology, including rapid interpretations, primary diagnosis and second opinions, continuing education and proficiency testing. All of these functions can be performed using small static digital images, real-time dynamic digital microscopy, or whole-slide images. This review will discuss the general principles of digital pathology, its methods and applications to cytologic specimens. As cytologic specimens have unique features compared to histopathology specimens, the key differences will be discussed. Technical and administrative issues in digital pathology applications and the outlook for the future of the field will be presented. Copyright © 2011 S. Karger AG, Basel.

Use of Iodine-based contrast media in digital full-field mammography - initial experience

International Nuclear Information System (INIS)

Diekmann, F.; Diekmann, S.; Taupitz, M.; Bick, U.; Winzer, K.-J.; Huettner, C.; Muller, S.; Jeunehomme, F.; Hamm, B.

2003-01-01

Aim: To investigate the use of iodine-based contrast media in digital full-field mammography. Methods: After performing initial phantom studies, seven patients underwent digital mammography (Senographe 2000D, GE Medical Systems, Milwaukee, USA) using a specially filtered beam before as well as 60, 120, and 180 seconds after injection of 80 ml of iodine contrast medium (Ultravist 370, Schering AG, Germany). The precontrast mammograms were then subtracted from the postcontrast mammograms and the resulting images compared with a contrast-enhanced dynamic MRI study, performed on all women. Results: Contrast medium accumulation within the tumors was visualized with a good quality in all cases. The conditions under which successful contrast-enhanced digital mammography can be performed were determined in phantom studies. Conclusions: Contrast-enhanced digital mammography has a potential for improving the visualization of breast tumors in mammography using special beam filtering, adjusted X-ray parameters, proper timing, and suitable subtraction software. (orig.) [de

A fully-automated software pipeline for integrating breast density and parenchymal texture analysis for digital mammograms: parameter optimization in a case-control breast cancer risk assessment study

Science.gov (United States)

Zheng, Yuanjie; Wang, Yan; Keller, Brad M.; Conant, Emily; Gee, James C.; Kontos, Despina

2013-02-01

Estimating a woman's risk of breast cancer is becoming increasingly important in clinical practice. Mammographic density, estimated as the percent of dense (PD) tissue area within the breast, has been shown to be a strong risk factor. Studies also support a relationship between mammographic texture and breast cancer risk. We have developed a fullyautomated software pipeline for computerized analysis of digital mammography parenchymal patterns by quantitatively measuring both breast density and texture properties. Our pipeline combines advanced computer algorithms of pattern recognition, computer vision, and machine learning and offers a standardized tool for breast cancer risk assessment studies. Different from many existing methods performing parenchymal texture analysis within specific breast subregions, our pipeline extracts texture descriptors for points on a spatial regular lattice and from a surrounding window of each lattice point, to characterize the local mammographic appearance throughout the whole breast. To demonstrate the utility of our pipeline, and optimize its parameters, we perform a case-control study by retrospectively analyzing a total of 472 digital mammography studies. Specifically, we investigate the window size, which is a lattice related parameter, and compare the performance of texture features to that of breast PD in classifying case-control status. Our results suggest that different window sizes may be optimal for raw (12.7mm2) versus vendor post-processed images (6.3mm2). We also show that the combination of PD and texture features outperforms PD alone. The improvement is significant (p=0.03) when raw images and window size of 12.7mm2 are used, having an ROC AUC of 0.66. The combination of PD and our texture features computed from post-processed images with a window size of 6.3 mm2 achieves an ROC AUC of 0.75.

An experimental investigation on reduced radiological penumbra for intermediate energy x-rays: Implications for small field radiosurgery

Science.gov (United States)

Keller, Brian Michael

Current day external beam radiation therapy typically uses x-ray energies in the megavoltage (6--18 MV) or in the superficial/orthovoltage (80--350 kVp) energy ranges. It has been found that intermediate energy x-rays (those greater than orthovoltage but sub-megavoltage) may offer an advantage in the field of high precision radiation therapy such as in radiosurgery. This advantage is a reduction in the radiological penumbra associated with small (less than about 3 cm) radiation dose fields. A consequence of reduced radiological penumbra is a more homogenous, conformal dose distribution in the patient with dose escalation and organ sparing made more feasible. The objectives of this thesis were as follows: to produce and to characterize an intermediate energy x-ray beam, to establish a method of accurate penumbra measurement at the micron level for millimeter size fields, to measure the radiological penumbra of single small intermediate energy x-ray fields, and to show the clinical consequences of a multiple beam irradiation in a stereotactic head phantom. A maximum photon energy of 1.2 +/- 0.1 MeV was determined for the intermediate energy x-ray spectrum at the expense of a low dose rate. A digital microscope with a computer controlled translation stage was investigated for its ability to resolve steep dose gradients in Gafchromic EBT film for field sizes as small as 1 mm and for photon energies as low as 100 kVp. The microscope-film system resolved gradients to within about 30 mum, limited by the inherent spatial resolution of the film, the noise of the system, and the uncertainties of measurement. Penumbra widths were compared for 1.2 MV versus 6 MV for identical irradiation conditions. In some instances, there was a five-fold reduction in the radiological penumbra of single 1.2 MV x-ray beams. A multiple beam arc irradiation demonstrated that the advantages seen with single beams carry over to multiple beams. The benefits of reduced radiological penumbra for

Mammographic features and subsequent risk of breast cancer: a comparison of qualitative and quantitative evaluations in the Guernsey prospective studies.

Science.gov (United States)

Torres-Mejía, Gabriela; De Stavola, Bianca; Allen, Diane S; Pérez-Gavilán, Juan J; Ferreira, Jorge M; Fentiman, Ian S; Dos Santos Silva, Isabel

2005-05-01

Mammographic features are known to be associated with breast cancer but the magnitude of the effect differs markedly from study to study. Methods to assess mammographic features range from subjective qualitative classifications to computer-automated quantitative measures. We used data from the UK Guernsey prospective studies to examine the relative value of these methods in predicting breast cancer risk. In all, 3,211 women ages > or =35 years who had a mammogram taken in 1986 to 1989 were followed-up to the end of October 2003, with 111 developing breast cancer during this period. Mammograms were classified using the subjective qualitative Wolfe classification and several quantitative mammographic features measured using computer-based techniques. Breast cancer risk was positively associated with high-grade Wolfe classification, percent breast density and area of dense tissue, and negatively associated with area of lucent tissue, fractal dimension, and lacunarity. Inclusion of the quantitative measures in the same model identified area of dense tissue and lacunarity as the best predictors of breast cancer, with risk increasing by 59% [95% confidence interval (95% CI), 29-94%] per SD increase in total area of dense tissue but declining by 39% (95% CI, 53-22%) per SD increase in lacunarity, after adjusting for each other and for other confounders. Comparison of models that included both the qualitative Wolfe classification and these two quantitative measures to models that included either the qualitative or the two quantitative variables showed that they all made significant contributions to prediction of breast cancer risk. These findings indicate that breast cancer risk is affected not only by the amount of mammographic density but also by the degree of heterogeneity of the parenchymal pattern and, presumably, by other features captured by the Wolfe classification.

Small Form Factor Information Storage Devices for Mobile Applications in Korea

Science.gov (United States)

Park, Young-Pil; Park, No-Cheol; Kim, Chul-Jin

Recently, the ubiquitous environment in which anybody can reach a lot of information data without any limitations on the place and time has become an important social issue. There are two basic requirements in the field of information storage devices which have to be satisfied; the first is the demand for the improvement of memory capacity to manage the increased data capacity in personal and official purposes. The second is the demand for new development of information storage devices small enough to be applied to mobile multimedia digital electronics, including digital camera, PDA and mobile phones. To summarize, for the sake of mobile applications, it is necessary to develop information storage devices which have simultaneously a large capacity and a small size. Korea possesses the necessary infrastructure for developing such small sized information storage devices. It has a good digital market, major digital companies, and various research institutes. Nowadays, many companies and research institutes including university cooperate together in the research on small sized information storage devices. Thus, it is expected that small form factor optical disk drives will be commercialized in the very near future in Korea.

Radiation field mapping in mammography units with TLDs

Energy Technology Data Exchange (ETDEWEB)

Castro, J.C.O.; Silva, J.O., E-mail: jonas.silva@ufg.br [Universidade Federal de Goiás (IFG), Goiânia (Brazil). Instituto de Física; Veneziani, G.R. [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo-SP (Brazil). Centro de Metrologia das Radiações

2017-07-01

Mammography is the most common imaging technique for breast cancer detection and its tracking. For dosimetry, is important to know the field intensity variation. In this work, TLD-100 were used to made a field mapping of a mammographic system from a hospital in Goiânia/GO. The maximum radiation intensity was 8 cm far from chest wall. The results obtained could be used in the optimization of the dosimetry in the equipment used in this work. (author)

Stereotaxic percutaneous core biopsy versus surgical biopsy of nonpalpable breast lesions using a standard mammographic table with an add-on device

International Nuclear Information System (INIS)

Levin, M.F.; Papoff, W.J.; Doan, L.; Eliasziw, M.

2001-01-01

To determine the accuracy of using a regular mammographic table with an add-on device for biopsy of nonpalpable breast lesions in women in a community hospital setting. During a 3-year period, 70 consenting women (39-80 years of age) with a nonpalpable mammographically suspicious lesion on routine screening mammography underwent 14-gauge automated percutaneous core biopsies, immediate needle localization and lumpectomy. The needle and surgical biopsy results were independently classified into 1 of 5 categories: cancer, fibroadenomal fibrocystic change, normal or other. The procedure was well tolerated, and all core specimens yielded adequate tissue for pathologic evaluation. There were 3 episodes of vasovagal reaction. There was complete agreement in histologic findings in 64 cases (91%), including 22 of 24 cancers (92%). The overall agreement for categorizing lesions was 91% (k 0.88), and there was 97% agreement (k = 0.94) for the classification of cancer versus benign lesion. The results are similar to those of studies performed with dedicated prone equipment. Stereotaxic core biopsies can be done safely and accurately in a community hospital setting with relatively inexpensive nondedicated mammographic equipment. (author)

Stereotaxic percutaneous core biopsy versus surgical biopsy of nonpalpable breast lesions using a standard mammographic table with an add-on device

Energy Technology Data Exchange (ETDEWEB)

Levin, M.F.; Papoff, W.J.; Doan, L.; Eliasziw, M. [St. Thomas-Elgin General Hospital, St. Thomas, Ontario (Canada)

2001-02-01

To determine the accuracy of using a regular mammographic table with an add-on device for biopsy of nonpalpable breast lesions in women in a community hospital setting. During a 3-year period, 70 consenting women (39-80 years of age) with a nonpalpable mammographically suspicious lesion on routine screening mammography underwent 14-gauge automated percutaneous core biopsies, immediate needle localization and lumpectomy. The needle and surgical biopsy results were independently classified into 1 of 5 categories: cancer, fibroadenomal fibrocystic change, normal or other. The procedure was well tolerated, and all core specimens yielded adequate tissue for pathologic evaluation. There were 3 episodes of vasovagal reaction. There was complete agreement in histologic findings in 64 cases (91%), including 22 of 24 cancers (92%). The overall agreement for categorizing lesions was 91% (k 0.88), and there was 97% agreement (k = 0.94) for the classification of cancer versus benign lesion. The results are similar to those of studies performed with dedicated prone equipment. Stereotaxic core biopsies can be done safely and accurately in a community hospital setting with relatively inexpensive nondedicated mammographic equipment. (author)

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

MMS Multipoint Electric Field Observations of Small-Scale Magnetic Holes

Science.gov (United States)

Goodrich, Katherine A.; Ergun, Robert E.; Wilder, Frederick; Burch, James; Torbert, Roy; Khotyaintsev, Yuri; Lindqvist, Per-Arne; Russell, Christopher; Strangeway, Robert; Magnus, Werner

2016-01-01

Small-scale magnetic holes (MHs), local depletions in magnetic field strength, have been observed multiple times in the Earths magnetosphere in the bursty bulk flow (BBF) braking region. This particular subset of MHs has observed scale sizes perpendicular to the background magnetic field (B) less than the ambient ion Larmor radius (p(sib i)). Previous observations by Time History of Events and Macroscale Interactions during Substorms (THEMIS) indicate that this subset of MHs can be supported by a current driven by the E x B drift of electrons. Ions do not participate in the E x B drift due to the small-scale size of the electric field. While in the BBF braking region, during its commissioning phase, the Magnetospheric Multiscale (MMS) spacecraft observed a small-scale MH. The electric field observations taken during this event suggest the presence of electron currents perpendicular to the magnetic field. These observations also suggest that these currents can evolve to smaller spatial scales.

Results of conservative surgery and radiation for mammographically detected ductal carcinoma in situ (DCIS)

International Nuclear Information System (INIS)

Fowble, B.; Hanlon, A.L.; Fein, D.A.; Hoffman, J.P.; Sigurdson, E.R.; Patchefsky, A.; Kessler, H.

1996-01-01

Purpose: The role of conservative surgery and radiation for mammographically detected DCIS is controversial. In particular, there is a paucity of data for outcome with radiation in a group of patients comparable to those treated with local excision and surveillance (mammographically detected DCIS ≤2.5 cm, negative resection margins, negative post-biopsy mammogram). The purpose of this study is to report long term outcome of conservative surgery and radiation for mammographically detected DCIS with emphasis on the results in patients (pts.) considered candidates for excision alone. Materials and Methods: From 1983 to 1992, 110 women with mammographically detected DCIS (calcifications 72%, mass ± calcifications 27%) and no prior history of breast cancer underwent needle localization biopsy followed by radiation. The median age of the patient population was 56 yrs. (range 37-81). The median followup was 5.3 yrs. (range .5-12). Re-excision was performed in 55%. Final margins of resection were negative in 62%, positive 7%, close 11%, and unknown 20%. Axillary dissection was performed in 31 pts. and all had negative nodes. 31% had a positive family history of breast cancer (1 affected relative-25 pts., two-7 pts., three-2 pts.). The most common predominant histologic subtype was comedo (54%) followed by cribriform (22%). The median pathologic tumor size was 8 mm (range 2 mm to 5 cm). A post-biopsy mammogram prior to radiation was performed in 46% of the patients. Radiation consisted of treatment to the entire breast (median 5000 cGy) with a boost to the primary site (97%) of an additional 1000 cGy. The median total dose to the primary site was 6040 cGy (range 5000 to 6660). Results: Three patients developed a recurrence in the treated breast at 52, 106, and 107 months. All 3 recurrences were invasive ductal cancers and all were treated with mastectomy. The location of the recurrence was in the same quadrant as the primary in 1 pt. and in a separate quadrant in 2 pts

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.

Normalized Noise Power Spectrum of Full Field Digital Mammography System

International Nuclear Information System (INIS)

Isa, Norriza Mohd; Wan Hassan, Wan Muhamad Saridan

2010-01-01

A method to measure noise power spectrum of a full field digital mammography system is presented. The effect of X-ray radiation dose, size and configuration of region of interest on normalized noise power spectrum (NNPS) was investigated. Flat field images were acquired using RQA-M2 beam quality technique (Mo/Mo anode-filter, 28 kV, 2 mm Al) with different clinical radiation doses. The images were cropped at about 4 cm from the edge of the breast wall and then divided into different size of non-overlapping or overlapping segments. NNPS was determined through detrending, 2-D fast Fourier transformation and normalization. Our measurement shows that high radiation dose gave lower NNPS at a specific beam quality.

Preliminary evaluation of a prototype stereoscopic a-Si:H-based X-ray imaging system for full-field digital mammography

International Nuclear Information System (INIS)

Darambara, D.G.; Speller, R.D.; Horrocks, J.A.; Godber, S.; Wilson, R.; Hanby, A.

2001-01-01

In a pre-clinical study, we have been investigating the potential of a-Si:H active matrix, flat panel imagers for X-ray full-field digital mammography through the development of an advanced 3D X-ray imaging system and have measured a number of their important imaging characteristics. To enhance the information embodied into the digital images produced by the a-Si array, stereoscopic images, created by viewing the object under examination from two angles and recombining the images, were obtained. This method provided us with a full 3D X-ray image of the test object as well as left and right perspective 2D images all at the same time. Within this scope, images of fresh, small human breast tissue specimens--normal and diseased--were obtained at ±2 deg., processed and stereoscopically displayed for a pre-clinical evaluation by radiologists. It was demonstrated that the stereoscopic presentation of the images provides important additional information and has potential benefits over the more traditional 2D data

Mammographic Density Reduction as a Prognostic Marker for Postmenopausal Breast Cancer: Results Using a Joint Longitudinal-Survival Modeling Approach.

Science.gov (United States)

Andersson, Therese M-L; Crowther, Michael J; Czene, Kamila; Hall, Per; Humphreys, Keith

2017-11-01

Previous studies have linked reductions in mammographic density after a breast cancer diagnosis to an improved prognosis. These studies focused on short-term change, using a 2-stage process, treating estimated change as a fixed covariate in a survival model. We propose the use of a joint longitudinal-survival model. This enables us to model long-term trends in density while accounting for dropout as well as for measurement error. We studied the change in mammographic density after a breast cancer diagnosis and its association with prognosis (measured by cause-specific mortality), overall and with respect to hormone replacement therapy and tamoxifen treatment. We included 1,740 women aged 50-74 years, diagnosed with breast cancer in Sweden during 1993-1995, with follow-up until 2008. They had a total of 6,317 mammographic density measures available from the first 5 years of follow-up, including baseline measures. We found that the impact of the withdrawal of hormone replacement therapy on density reduction was larger than that of tamoxifen treatment. Unlike previous studies, we found that there was an association between density reduction and survival, both for tamoxifen-treated women and women who were not treated with tamoxifen. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Sloan Digital Sky Survey Photometric Calibration Revisited

International Nuclear Information System (INIS)

Marriner, John

2012-01-01

The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

Sloan Digital Sky Survey Photometric Calibration Revisited

Energy Technology Data Exchange (ETDEWEB)

Marriner, John; /Fermilab

2012-06-29

The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

Improvement of Breast Cancer Detection Using Non-subsampled Contourlet Transform and Super-Resolution Technique in Mammographic Images

Directory of Open Access Journals (Sweden)

Fatemeh Pak

2015-05-01

Full Text Available Introduction Breast cancer is one of the most life-threatening conditions among women. Early detection of this disease is the only way to reduce the associated mortality rate. Mammography is a standard method for the early detection of breast cancer. Today, considering the importance of breast cancer detection, computer-aided detection techniques have been employed to increase the quality of mammographic images and help physicians reduce false positive rate (FPR. Materials and Methods In this study, a method was proposed for improving the quality of mammographic images to help radiologists establish a prompt and accurate diagnosis. The proposed approach included three major parts including pre-processing, feature extraction, and classification. In the pre-processing stage, the region of interest was determined and the image quality was improved by non-subsampled contourlet transform and super-resolution algorithm. In the feature extraction stage, some features of image components were extracted and skewness of each feature was calculated. Finally, a support vector machine was utilized to classify the features and determine the probability of benignity or malignancy of the disease. Results Based on the obtained results using Mammographic Image Analysis Society (MIAS database, the mean accuracy was estimated at 87.26% and maximum accuracy was 96.29%. Also, the mean and minimum FPRs were estimated at 9.55% and 2.87%, respectively.     Conclusion The results obtained using MIAS database indicated the superiority of the proposed method to other techniques. The reduced FPR in the proposed method was a significant finding in the present article.

New techniques in digital holography

CERN Document Server

Picart, Pascal

2015-01-01

A state of the art presentation of important advances in the field of digital holography, detailing advances related to fundamentals of digital holography, in-line holography applied to fluid mechanics, digital color holography, digital holographic microscopy, infrared holography, special techniques in full field vibrometry and inverse problems in digital holography

Laboratory and Field Investigations of Small Crater Repair Technologies

National Research Council Canada - National Science Library

Priddy, Lucy P; Tingle, Jeb S; McCaffrey, Timothy J; Rollings, Ray S

2007-01-01

.... This airfield damage repair (ADR) investigation consisted of laboratory testing of selected crater fill and capping materials, as well as full-scale field testing of small crater repairs to evaluate field mixing methods, installation...

Analysis of reconstructed interference fields in digital holographic interferometry using the polynomial phase transform

International Nuclear Information System (INIS)

Gorthi, Sai Siva; Rastogi, Pramod

2009-01-01

A noisy wrapped phase map is the end-output of commonly employed phase estimation methods in digital holographic interferometry. Hence filtering and unwrapping are necessary to obtain continuous phase distributions. This paper introduces a new approach for phase estimation in digital holographic interferometry using the polynomial phase transform. The proposed approach directly provides an accurate estimation of the unwrapped phase distribution from a noisy reconstructed interference field, thereby bypassing cumbersome and error-prone filtering and 2D phase unwrapping procedures

Digital Signage

OpenAIRE

Fischer, Karl Peter

2011-01-01

Digital Signage for in-store advertising at gas stations/retail stores in Germany: A field study Digital Signage networks provide a novel means of advertising with the advantage of easily changeable and highly customizable animated content. Despite the potential and increasing use of these media empirical research is scarce. In a field study at 8 gas stations (with integrated convenience stores) we studied the effect of digital signage advertising on sales for different products and servi...

Design and field tests of a modified small mammallivetrap

African Journals Online (AJOL)

-vinyl-chloride) and metal small mammal live-trap has been developed and subjected to field tests. The PVC traps captured greater numbers of very small rodents and shrews but fewer large rodents than did hardboard ones. s. Afr. J. Zool.

Using tumor phenotype, histological tumor distribution, and mammographic appearance to explain the survival differences between screen-detected and clinically detected breast cancers.

Science.gov (United States)

Chuang, Shu-Lin; Chen, Sam Li-Sheng; Yu, Cheng-Ping; Chang, King-Jen; Yen, Amy Ming-Fang; Chiu, Sherry Yueh-Hsia; Fann, Jean Ching-Yuan; Tabár, László; Stephen, Duffy W; Smith, Robert A; Chen, Hsiu-Hsi

2014-08-01

In the era of mass screening for breast cancer with mammography, it has been noted that conventional tumor attributes and mammographic appearance are insufficient to account for the better prognosis of screen-detected tumors. Such prognostication may require additional updated pathological information regarding tumor phenotype (e.g., basal status) and histological tumor distribution (focality). We investigated this hypothesis using a Bayesian approach to analyze breast cancer data from Dalarna County, Sweden. We used data for tumors diagnosed in the Swedish Two-County Trial and early service screening period, 1977-1995, and from the mature service screening period, 1996-1998. In the early period of mammographic screening (1977-1995), the crude hazard ratio (HR) of breast cancer death for screen-detected cases compared with symptomatic ones was 0.22 (95% CI: 0.17-0.29) compared with 0.53 (95% CI: 0.34-0.76) when adjusted for conventional tumor attributes only. Using the data from the mature service screening period, 1996-1998, the HR was 0.23 (95% CI: 0.08-0.44) unadjusted and 0.71 (95% CI: 0.26-1.47) after adjustment for tumor phenotype, mammographic appearance, histological tumor distribution, and conventional tumor attributes. The area under the ROC curve (AUC) for the prediction of breast cancer deaths using these variables without the detection mode was 0.82, only slightly less than that observed when additionally including the detection mode (AUC=0.83). Using Freedman statistics, conventional tumor attributes and mammographic appearances explained 58% (95% CI: 57.5-58.6%) of the difference of breast cancer survival between the screen-detected and the clinically detected breast cancers, whereas the corresponding figure was increased to 77% (95% CI: 75.6-77.6%) when adding the two information on tumor phenotype and histological tumor distribution. The results indicated that conventional tumor attributes and mammographic appearance are not sufficient to be

Scatter radiation in digital tomosynthesis of the breast

International Nuclear Information System (INIS)

Sechopoulos, Ioannis; Suryanarayanan, Sankararaman; Vedantham, Srinivasan; D'Orsi, Carl J.; Karellas, Andrew

2007-01-01

Digital tomosynthesis of the breast is being investigated as one possible solution to the problem of tissue superposition present in planar mammography. This imaging technique presents various advantages that would make it a feasible replacement for planar mammography, among them similar, if not lower, radiation glandular dose to the breast; implementation on conventional digital mammography technology via relatively simple modifications; and fast acquisition time. One significant problem that tomosynthesis of the breast must overcome, however, is the reduction of x-ray scatter inclusion in the projection images. In tomosynthesis, due to the projection geometry and radiation dose considerations, the use of an antiscatter grid presents several challenges. Therefore, the use of postacquisition software-based scatter reduction algorithms seems well justified, requiring a comprehensive evaluation of x-ray scatter content in the tomosynthesis projections. This study aims to gain insight into the behavior of x-ray scatter in tomosynthesis by characterizing the scatter point spread functions (PSFs) and the scatter to primary ratio (SPR) maps found in tomosynthesis of the breast. This characterization was performed using Monte Carlo simulations, based on the Geant4 toolkit, that simulate the conditions present in a digital tomosynthesis system, including the simulation of the compressed breast in both the cranio-caudal (CC) and the medio-lateral oblique (MLO) views. The variation of the scatter PSF with varying tomosynthesis projection angle, as well as the effects of varying breast glandular fraction and x-ray spectrum, was analyzed. The behavior of the SPR for different projection angle, breast size, thickness, glandular fraction, and x-ray spectrum was also analyzed, and computer fit equations for the magnitude of the SPR at the center of mass for both the CC and the MLO views were found. Within mammographic energies, the x-ray spectrum was found to have no appreciable

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

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

Behavior of small ferromagnetic particles in traveling magnetic field

Science.gov (United States)

Deych, V. G.; Terekhov, V. P.

1985-03-01

Forces and moments acting on a magnetizable body in a traveling magnetic field are calculated for a body with dimensions much smaller than the wavelength of the magnetic field. It is assumed that a particle of given linear dimension does not have a constant magnetic moment. The material of a particle is characterized by its magnetic permeability and electrical conductivity. The hypothesis that rotation plays a major role in the behavior of small particles is confirmed and the fact that a small particle rolls on a plane, without sliding, when the surface is perfectly rough, in the opposite direction from which the magnetic field travels is explained. Calculations are based on the magnetohydrodynamic equations for a quasi steady magnetic field, and the induced Foucault eddy currents are considered. The results are applicable to transport of ferrofluids and to such metallurgical devices as separators.

Normalized noise power spectrum of full field digital mammography system

International Nuclear Information System (INIS)

Norriza Mohd Isa; Wan Muhamad Saridan Wan Hassan

2009-01-01

A method to measure noise power spectrum of a full field digital mammography system is presented. The effect of X-ray radiation dose, size and configuration of region of interest on normalized noise power spectrum (NNPS) was investigated. Flat field images were acquired using RQA-M2 beam quality technique (Mo/Mo anode-filter, 28 kV, 2 mm Al) with different clinical radiation doses. The images were cropped at about 4 cm from the edge of the breast wall and then divided into different size of non-overlapping or overlapping segments. NNPS was determined through detrending, 2-D fast Fourier transformation and normalization. Our measurement shows that high radiation dose gave lower NNPS at a specific beam quality. (Author)

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

Application of digital field photographs as documents for tropical plant inventory.

Science.gov (United States)

LaFrankie, James V; Chua, Anna I

2015-05-01

We tested the credibility and significance of digital field photographs as supplements or substitutes for conventional herbarium specimens with particular relevance to exploration of the tropics. We made 113 collections in triplicate at a species-rich mountain in the Philippines while we took 1238 digital photographs of the same plants. We then identified the plants from the photographs alone, categorized the confidence of the identification and the reason for failure to identify, and compared the results to identifications based on the dried specimens. We identified 72.6% of the photographic sets with high confidence and 27.4% with low confidence or only to genus. In no case was a confident identification altered by subsequent examination of the dried specimen. The failure to identify photographic sets to species was due to the lack of a key feature in 67.8% of the cases and due to a poorly understood taxonomy in 32.2%. We conclude that digital photographs cannot replace traditional herbarium specimens as the primary elements that document tropical plant diversity. However, photographs represent a new and important artifact that aids an expedient survey of tropical plant diversity while encouraging broad public participation.

Evaluation of the quality of CR mammography images in Chugoku Rosai Hospital. Visual evaluation and digital evaluation

International Nuclear Information System (INIS)

Makihata, Hiroshi; Fukuda, Tomoya; Aomori, Masaji; Hara, Shinji

2005-01-01

New mammography system (50-micrometer system) composed of Fuji computed tomography (FCR) both sides IP, 5000MA and dry imager was introduced in the Department of Physical Checkup of Chugoku Rosai Hospital in 2003. We performed visual evaluation and digital evaluation using 50-micrometer system in accordance with (the quality control guidance of) Non-Profit Organization the Central Committee on Quality Control of Mammographic Screening. In visual evaluation using RMI156 phantom the system cleared the quality control guidance about a fiber, calcification, and masses. On step phantom, it passed about 10 steps, masses, and calcifications. Since a success standard was not announced officially, the performance in digital evaluation cannot be judged and only the result is presented. In digital evaluation, signal-to-noise ratio (SNR) is 14.9, root of mean squares (RMS) is 32.9, SNRC is 16.4, SNRT is 3.65. This system image has high sharpness and is considered from the result in visual evaluation to have the ability of offering images with a high degree of information. (author)

Automatic alignment device for focal spot measurements in the center of the field for mammography

International Nuclear Information System (INIS)

Vieira, Marcelo A.C.; Watanabe, Alex O.; Oliveira Junior, Paulo D.; Schiabel, Homero

2010-01-01

Some quality control procedures used for mammography, such as focal spot evaluation, requires previous alignment of the measurement equipment with the X-ray central beam. However, alignment procedures are, in general, the most difficult task and the one that needs more time to be performed. Moreover, the operator sometimes is exposed to radiation during this procedure. This work presents an automatic alignment system for mammographic equipment that allows locating the central ray of the radiation beam and, immediately, aligns with it by dislocating itself automatically along the field. The system consists on a bidirectional moving device, connected to a CCD sensor for digital radiographic image acquisition. A computational analysis of a radiographic image, acquired at any position on the field, is performed in order to determine its positioning under the X-ray beam. Finally, a mechanical system for two moving directions, electronically controlled by a microcontroller under USB communication, makes the system to align automatically with the radiation beam central ray. The alignment process is fully automatic, fast and accurate, with no operator exposure to radiation, which allows a considerable time saving for quality control procedures achievement for mammography. (author)

Breast Density Among the Three Major Ethnic Groups of Women in Malaysia from a Full-Filed Digital Mammography System

International Nuclear Information System (INIS)

Noriah Jamal; Cheung, H.S.

2014-01-01

We carried out a prospective study of breast density Full-Field Digital mammograms performed on 668 Malaysian women from three ethnic groups at a voluntary screening mammographic center in Kuala Lumpur, Malaysia. Of these women, 259 were Malays (38.8 %), 298 were Chinese (44.6 %) and 111 were Indians (16.6 %). The Tabar breast density classification (I-V) was used to evaluate breast density. A Stepwise multiple regression analysis was used to test for significant difference in breast density for the three ethnic groups. Data was also analyzed using descriptive statistics. We found that Pattern I was seen in 49.4 % Malay, 47.3 % Chinese and 40.5 % Indian women. Predominantly fatty breasts (Pattern II and III) were seen on mammograms of 36.3 % Malay, 11.1 % Chinese and 25.2 % Indian women. Dense type IV and V patterns were seen in 20.8 % Malay, 29.5 % Chinese and 42 % Indian women. There was no statistically significant difference (p>0.01) in breast density in the three ethnic groups. The breast density reduces with increasing age in all three ethnic groups. (Author)

A compact wideband precision impedance measurement system based on digital auto-balancing bridge

International Nuclear Information System (INIS)

Hu, Binxin; Wang, Jinyu; Song, Guangdong; Zhang, Faxiang

2016-01-01

The ac impedance spectroscopy measurements are predominantly taken by using impedance analyzers based on analog auto-balancing bridge. However, those bench-top analyzers are generally complicated, bulky and expensive, thus limiting their usage in industrial field applications. This paper presents the development of a compact wideband precision measurement system based on digital auto-balancing bridge. The methods of digital auto-balancing bridge and digital lock-in amplifier are analyzed theoretically. The overall design and several key sections including null detector, direct digital synthesizer-based sampling clock, and digital control unit are introduced in detail. The results show that the system achieves a basic measurement accuracy of 0.05% with a frequency range of 20 Hz–2 MHz. The advantages of versatile measurement capacity, fast measurement speed, small size and low cost make it quite suitable for industrial field applications. It is demonstrated that this system is practical and effective by applying in determining the impedance-temperature characteristic of a motor starter PTC thermistor. (paper)

TH-EF-204-05: Application of Small-Field Treatment: The Promises and Pitfalls of SBRT

International Nuclear Information System (INIS)

Ford, E.

2016-01-01

Joanna E. Cygler, Jan Seuntjens, J. Daniel Bourland, M. Saiful Huq, Josep Puxeu Vaque, Daniel Zucca Aparicio, Tatiana Krylova, Yuri Kirpichev, Eric Ford, Caridad Borras Stereotactic Radiation Therapy (SRT) utilizes small static and dynamic (IMRT) fields, to successfully treat malignant and benign diseases using techniques such as Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT). SRT is characterized by sharp dose gradients for individual fields and their resultant dose distributions. For appropriate targets, small field radiotherapy offers improved treatment quality by allowing better sparing of organs at risk while delivering the prescribed target dose. Specialized small field treatment delivery systems, such as robotic-controlled linear accelerators, gamma radiosurgery units, and dynamic arc linear accelerators may utilize rigid fixation, image guidance, and tumor tracking, to insure precise dose delivery to static or moving targets. However, in addition to great advantages, small field delivery techniques present special technical challenges for dose calibration due to unique geometries and small field sizes not covered by existing reference dosimetry protocols such as AAPM TG-51 or IAEA TRS 398. In recent years extensive research has been performed to understand small field dosimetry and measurement instrumentation. AAPM, IAEA and ICRU task groups are expected to provide soon recommendations on the dosimetry of small radiation fields. In this symposium we will: 1] discuss the physics, instrumentation, methodologies and challenges for small field radiation dose measurements; 2] review IAEA and ICRU recommendations on prescribing, recording and reporting of small field radiation therapy; 3] discuss selected clinical applications and technical aspects for specialized image-guided, small field, linear accelerator based treatment techniques such as IMRT and SBRT. Learning Objectives: To learn the physics of small fields in contrast to

TH-EF-204-05: Application of Small-Field Treatment: The Promises and Pitfalls of SBRT

Energy Technology Data Exchange (ETDEWEB)

Ford, E. [University of Washington (United States)

2016-06-15

Joanna E. Cygler, Jan Seuntjens, J. Daniel Bourland, M. Saiful Huq, Josep Puxeu Vaque, Daniel Zucca Aparicio, Tatiana Krylova, Yuri Kirpichev, Eric Ford, Caridad Borras Stereotactic Radiation Therapy (SRT) utilizes small static and dynamic (IMRT) fields, to successfully treat malignant and benign diseases using techniques such as Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT). SRT is characterized by sharp dose gradients for individual fields and their resultant dose distributions. For appropriate targets, small field radiotherapy offers improved treatment quality by allowing better sparing of organs at risk while delivering the prescribed target dose. Specialized small field treatment delivery systems, such as robotic-controlled linear accelerators, gamma radiosurgery units, and dynamic arc linear accelerators may utilize rigid fixation, image guidance, and tumor tracking, to insure precise dose delivery to static or moving targets. However, in addition to great advantages, small field delivery techniques present special technical challenges for dose calibration due to unique geometries and small field sizes not covered by existing reference dosimetry protocols such as AAPM TG-51 or IAEA TRS 398. In recent years extensive research has been performed to understand small field dosimetry and measurement instrumentation. AAPM, IAEA and ICRU task groups are expected to provide soon recommendations on the dosimetry of small radiation fields. In this symposium we will: 1] discuss the physics, instrumentation, methodologies and challenges for small field radiation dose measurements; 2] review IAEA and ICRU recommendations on prescribing, recording and reporting of small field radiation therapy; 3] discuss selected clinical applications and technical aspects for specialized image-guided, small field, linear accelerator based treatment techniques such as IMRT and SBRT. Learning Objectives: To learn the physics of small fields in contrast to

Does digital mammography suppose an advance in early diagnosis? Trends in performance indicators 6 years after digitalization.

Science.gov (United States)

Sala, Maria; Domingo, Laia; Macià, Francesc; Comas, Mercè; Burón, Andrea; Castells, Xavier

2015-03-01

To provide a complete evaluation of the long-term impact of full-field digital mammography (FFDM) on the improvement of early diagnosis in a population-based screening program. We included 82,961 screen-film mammograms (SFM) and 79,031 FFDM from women aged 50-69 screened biennially from 1995-2010 in Spain and followed-up to 2012. The first screening round of the program was excluded. Rates of cancer detection, interval cancer, tumoral characteristics and other quality indicators were compared between SFM and FFDM periods using the Chi-square test. Multivariate logistic regression models were fitted. Detection of ductal carcinoma in situ (DCIS) significantly increased with FFDM (0.05 % vs 0.09 %; p = 0.010), along with the proportion of small invasive cancers (Digitalization has supposed an improvement in early diagnosis because DCIS and small invasive cancers increased without a change in detection rate. Moreover, false-positive reduction without an increase in the interval cancer rate was confirmed.

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.

A phase transition between small- and large-field models of inflation

International Nuclear Information System (INIS)

Itzhaki, Nissan; Kovetz, Ely D

2009-01-01

We show that models of inflection point inflation exhibit a phase transition from a region in parameter space where they are of large-field type to a region where they are of small-field type. The phase transition is between a universal behavior, with respect to the initial condition, at the large-field region and non-universal behavior at the small-field region. The order parameter is the number of e-foldings. We find integer critical exponents at the transition between the two phases.

Mammographic breast density in recent and longer-standing ethiopian immigrants to israel.

Science.gov (United States)