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Breast Computed Tomography (bCT) is a three-dimensional imaging technique that is raising interest among radiologists as a viable alternative to mammographic planar imaging. In X-rays imaging it would be desirable to maximize the capability of discriminating different tissues, described by the Contrast to Noise Ratio (CNR), while minimizing the dose (i.e. the radiological risk). Both dose and CNR are functions of the X-ray energy. This work aims at experimentally investigating the optimal energy that, at fixed dose, maximizes the CNR between glandular and adipose tissues. Acquisitions of both tissue-equivalent phantoms and actual breast specimens have been performed with the bCT system implemented within the Syrma-3D collaboration at the Syrmep beamline of the Elettra synchrotron (Trieste). The experimental data have been also compared with analytical simulations and the results are in agreement. The CNR is maximized at energies around 26-28 keV. These results are in line with the outcomes of a previously presented simulation study which determined an optimal energy of 28 keV for a large set of breast phantoms with different diameters and glandular fractions. Finally, a study on photon starvation has been carried out to investigate how far the dose can be reduced still having suitable images for diagnostics.

Breast computed tomography (BCT) is an emerging application of X-ray tomography in radiological practice. A few clinical prototypes are under evaluation in hospitals and new systems are under development aiming at improving spatial and contrast resolution and reducing delivered dose. At the same time, synchrotron-radiation phase-contrast mammography has been demonstrated to offer substantial advantages when compared with conventional mammography. At Elettra, the Italian synchrotron radiation facility, a clinical program of phase-contrast BCT based on the free-space propagation approach is under development. In this paper, full-volume breast samples imaged with a beam energy of 32 keV delivering a mean glandular dose of 5 mGy are presented. The whole acquisition setup mimics a clinical study in order to evaluate its feasibility in terms of acquisition time and image quality. Acquisitions are performed using a high-resolution CdTe photon-counting detector and the projection data are processed via a phase-retrieval algorithm. Tomographic reconstructions are compared with conventional mammographic images acquired prior to surgery and with histologic examinations. Results indicate that BCT with monochromatic beam and free-space propagation phase-contrast imaging provide relevant three-dimensional insights of breast morphology at clinically acceptable doses and scan times.

The aim of this study was to optimise the experimental protocol and data analysis for in-vivo breast cancer x-ray imaging. Results are presented of the experiment at the SYRMEP beamline of Elettra Synchrotron using the propagation-based phase-contrast mammographic tomography method, which incorporates not only absorption, but also x-ray phase information. In this study the images of breast tissue samples, of a size corresponding to a full human breast, with radiologically acceptable x-ray doses were obtained, and the degree of improvement of the image quality (from the diagnostic point of view) achievable using propagation-based phase-contrast image acquisition protocols with proper incorporation of x-ray phase retrieval into the reconstruction pipeline was investigated. Parameters such as the x-ray energy, sample-to-detector distance and data processing methods were tested, evaluated and optimized with respect to the estimated diagnostic value using a mastectomy sample with a malignant lesion. The results of quantitative evaluation of images were obtained by means of radiological assessment carried out by 13 experienced specialists. A comparative analysis was performed between the x-ray and the histological images of the specimen. The results of the analysis indicate that, within the investigated range of parameters, both the objective image quality characteristics and the subjective radiological scores of propagation-based phase-contrast images of breast tissues monotonically increase with the strength of phase contrast which in turn is directly proportional to the product of the radiation wavelength and the sample-to-detector distance. The outcomes of this study serve to define the practical imaging conditions and the CT reconstruction procedures appropriate for low-dose phase-contrast mammographic imaging of live patients at specially designed synchrotron beamlines.

This annual survey, conducted by the Italian group for mammography screening (GISMa), collects individual data on diagnosis and treatment of about 50% of screen-detected, operated lesions in Italy. The 2011-2012 results show good overall quality and an improving trend over time. A number of critical issues have been identified, including waiting times (which have had a worsening trend over the years) and compliance with the recommendation of not performing frozen section examination on small lesions. Pre-operative diagnosis improved constantly over time, but there is still a large variation between Regions and programmes. For almost 90% of screen-detected invasive cancers a sentinel lymph node (SLN) biopsy was performed on the axilla, avoiding a large number of potentially harmful dissections. On the other hand, potential overuse of SLN dissection for ductal carcinoma in situ, although apparently starting to decline, deserves further investigation. The detailed results have been distributed, among other ways by means of a web-based data-warehouse, to regional and local screening programmes, in order to allow multidisciplinary discussion and identification of the appropriate solutions to any issues documented by the data. The problem of waiting times should be assigned priority. Specialist Breast Units with adequate case volume and enough resources would provide the best setting for making monitoring effective in producing quality improvements with shorter waiting times.

This work presents the first study of x-ray phase contrast imaging based on a simple implementation of the edge illumination method (EIXPCi) in the field of mammography with synchrotron radiation. A simplified EIXPCi set-up was utilized to study a possible application in mammography at clinical doses. Moreover, through a novel algorithm capable of separating and quantifying absorption and phase perturbations of images acquired in EIXPCi modality, it is possible to extract quantitative information on breast images, allowing an accurate tissue identification. The study was carried out at the SYRMEP beamline of Elettra synchrotron radiation facility (Trieste, Italy), where a mastectomy specimen was investigated with the EIXPCi technique. The sample was exposed at three different energies suitable for mammography with synchrotron radiation in order to test the validity of the novel algorithm in extracting values of linear attenuation coefficients integrated over the sample thickness. It is demonstrated that the quantitative data are in good agreement with the theoretical values of linear attenuation coefficients calculated on the hypothesis of the breast with a given composition. The results are promising and encourage the current efforts to apply the method in mammography with synchrotron radiation.

The first clinical study of phase-contrast mammography (PCM) with synchrotron radiation was carried out at the Synchrotron Radiation for Medical Physics beamline of the Elettra synchrotron radiation facility in Trieste (Italy) in 2006-2009. The study involved 71 patients with unresolved breast abnormalities after conventional digital mammography and ultrasonography exams carried out at the Radiology Department of Trieste University Hospital. These cases were referred for mammography at the synchrotron radiation facility, with images acquired using a propagation-based phase-contrast imaging technique. To investigate the contribution of phase-contrast effects to the image quality, two experienced radiologists specialized in mammography assessed the visibility of breast abnormalities and of breast glandular structures. The images acquired at the hospital and at the synchrotron radiation facility were compared and graded according to a relative seven-grade visual scoring system. The statistical analysis highlighted that PCM with synchrotron radiation depicts normal structures and abnormal findings with higher image quality with respect to conventional digital mammography.

Objective: The aim of this study was to evaluate the feasibility of phase-contrast mammography with synchrotron radiation using a high-resolution computed radiology (CR) system devoted to mammography., Materials and Methods: The study was performed at the Synchrotron Radiation for Medical Physics (SYRMEP) beamline of the Elettra synchrotron radiation (SR) facility in Trieste (Italy); X-ray beams were in the range 16-22 keV with a high degree of monochromaticity and spatial coherence. The CR system evaluated is the FCR Profect CS by Fujifilm Global. The first images were obtained from test objects and surgical breast specimens. Images obtained using SR and both screen-film and the CR system were compared with images of the same samples acquired with digital mammography equipment. In view of the good quality of the results obtained, the CR system was used in two mammographic examinations with SR., Results: Images acquired using SR and both screen-film and CR were obtained with the same level of delivered dose. Image quality obtained with CR was similar or superior to that of screen-film images. Moreover, the digital images obtained with SR were always better than those acquired using the digital mammography system., Conclusions: Phase-contrast mammography with SR using the studied CR system is a feasible option.

Purpose: To prospectively evaluate the diagnostic contribution of mammography with synchrotron radiation in patients with questionable or suspicious breast abnormalities identified at combined digital mammography (DM) and ultrasonography (US)., Materials and Methods: The ethics committee approved this prospective study, and written informed consent was obtained from all patients. Mammography with synchrotron radiation was performed with a phase-detection technique at a synchrotron radiation laboratory. Forty-nine women who met at least one of the inclusion criteria (palpable mass, focal asymmetry, architectural distortion, or equivocal or suspicious mass at DM; none clarified at US) were enrolled. Forty-seven women (mean age, 57.8 years ± 8.8 [standard deviation]; age range, 43-78 years) completed the study protocol, which involved biopsy or follow-up for 1 year as the reference standard. Breast Imaging Reporting and Data System (BI-RADS) scores of 1-3 were considered to indicate a negative result, while scores 4-5 were considered to indicate a positive result. The visibility of breast abnormalities and the glandular parenchymal structure at DM and at mammography with synchrotron radiation was compared by using the Wilcoxon signed rank test., Results: In 29 of the 31 patients with a final diagnosis of benign entity, mammography with synchrotron radiation yielded BI-RADS scores of 1-3. In 13 of the remaining 16 patients with a final diagnosis of malignancy, mammography with synchrotron radiation yielded BI-RADS scores of 4-5. Therefore, a sensitivity of 81% (13 of 16 patients) and a specificity of 94% (29 of 31 patients) were achieved with use of the described BI-RADS dichotomization system., Conclusion: These study results suggest that mammography with synchrotron radiation can be used to clarify cases of questionable or suspicious breast abnormalities identified at DM., Supplemental Material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11100745/-/DC1., (RSNA, 2011)

A clinical program for X-ray phase contrast (PhC) mammography with synchrotron radiation (SR) has been started in March 2006 at the SYRMEP beamline of Elettra, the SR facility in Trieste, Italy. The original beamline layout has been modified substantially and a clinical facility has been realized. In order to fulfill all security requirements, dedicated systems have been designed and implemented, following redundancy criteria and "fail safe" philosophy. Planar radiographic images are obtained by scanning simultaneously the patient and the detector through the stationary and laminar SR beam. In this first phase of the project a commercial screen-film system has been used as image receptor. Upon approval by the respective authorities, the mammography program is about half way to conclusion. Up to now about 50 patients have been examined. The patients are volunteers recruited by the radiologist after conventional examinations at the hospital resulted in an uncertain diagnosis. As an example one case of PhC SR mammography is shown and compared to conventional digital mammography. Preliminary analysis shows the high diagnostic quality of the PhC SR images that were acquired with equal or less delivered dose compared to the conventional ones.

The authors evaluated the effect on mammographic examinations of the use of synchrotron radiation to detect phase-perturbation effects, which are higher than absorption effects for soft tissue in the energy range of 15-25 keV. Detection of phase-perturbation effects was possible because of the high degree of coherence of synchrotron radiation sources. Synchrotron radiation images were obtained of a mammographic phantom and in vitro breast tissue specimens and compared with conventional mammographic studies. On the basis of grades assigned by three reviewers, image quality of the former was considerably higher, and the delivered dose was fully compatible.

Phase contrast x-ray imaging is a powerful technique for the detection of low-contrast details in weakly absorbing objects. This method is of possible relevance in the field of diagnostic radiology. In fact, imaging low-contrast details within soft tissue does not give satisfactory results in conventional x-ray absorption radiology, mammography being a typical example. Nevertheless, up to now all applications of the phase contrast technique, carried out on thin samples, have required radiation doses substantially higher than those delivered in conventional radiological examinations. To demonstrate the applicability of the method to mammography we produced phase contrast images of objects a few centimetres thick while delivering radiation doses lower than or comparable to doses needed in standard mammographic examinations (typically approximately 1 mGy mean glandular dose (MGD)). We show images of a custom mammographic phantom and of two specimens of human breast tissue obtained at the SYRMEP bending magnet beamline at Elettra, the Trieste synchrotron radiation facility. The introduction of an intensifier screen enabled us to obtain phase contrast images of these thick samples with radiation doses comparable to those used in mammography. Low absorbing details such as 50 microm thick nylon wires or thin calcium deposits (approximately 50 microm) within breast tissue, invisible with conventional techniques, are detected by means of the proposed method. We also find that the use of a bending magnet radiation source relaxes the previously reported requirements on source size for phase contrast imaging. Finally, the consistency of the results has been checked by theoretical simulations carried out for the purposes of this experiment.

Abstract: The purpose of this study is evaluation of therapeutic impact of magnetic resonance imaging (MRI) in breast cancer patients that cannot be imaged adequately with traditional radiology: dense breasts, microcalcifications suspicious for carcinoma in situ or discordance between mammography and ultrasound. A review was performed of 493 patients’ records: determination of breast MRI effect on clinical management was made for the selected 70 cases by analysing pre-MRI and post-MRI therapeutic plans. Analysis of final pathology was useful to determine if the change in surgical plan prompted by MRI was appropriate. Breast MRI added clinical information in 52.9% of patients that resulted in 44.3% of management changes that were judged as appropriate in 83.9% of cases. Breast MRI provides additional useful information, but causes more extensive surgery (40%) with no proven prognostic benefit. MRI should be considered optional in the clinical staging of breast cancer and performed in selected cases. [Copyright &y& Elsevier]