Microcalcifications In Images Research Articles

Searching for a twinkling artefact in breast microcalcifications using B-flow ultrasonic non-doppler technology: a prospective study

INTRODUCTION: The rapid rejuvenation of breast cancer in recent years has made it necessary to look for non-X-ray methods of imaging microcalcifications in women not yet covered by mammography screening. Developing technologies to see these microcalcifications on ultrasound is a promising goal, potentially reducing the number of unnecessary biopsies.OBJECTIVE: Evaluation of factors influencing the ability of the B-flow technique to detect the presence of a flickering artifact in patients with microcalcifications detected by mammography.MATERIALS AND METHODS: A prospective study of 57 patients with microcalcifications detected on mammograms was conducted. The Nondoppler technology of B-flow ultrasound examination was used for targeted ultrasound with the search for these areas during ultrasound. The possibilities of visualization of the twinkle artifact were evaluated for various microcalcifications in size, distribution, their number, and for pathological processes of different nature. Images in B-flow mode were found to be positive when a bright local flash occurred against a dark background in B-mode. Verification of diagnostic findings was performed by ultrasound-guided core- biopsy from areas with a twinkle artifact (in the presence of an imaging area during ultrasound) or with stereotactic biopsy (in the absence of visualization of the suspicious area with ultrasound with B-flow).Statistics: The ANOVA test was used for triple pairwise comparisons between positive groups. The p<0.05 value was considered statistically significant.RESULTS: According to the results of the study, out of 57 cases with microcalcifications, 34 (60%) recorded a twinkle artifact. The amount of microcalcifications with a visualized twinkle effect in B-flow was significantly higher in benign processes 34 (82.9%) out of 41, and less often in malignant 8 (50%) out of 16 (p=0.035). The effect of calcification morphology on the mammogram on their detection by ultrasound in the B-flow mode (p=0.035) was statistically significant. The most frequently manifested twinkle artifact were rounded, regular-shaped calcifications in 19 (95%) out of 20, which were found in granulomatous mastitis, fibrocystic changes, fibroadenomas, sclerosing adenosis, as well as polymorphic calcifications in 7 (63.6%) of 11. In the B-flow mode, it was not possible to obtain a twinkle artifact mainly with point small calcifications of 9 (69.2%) out of 13, and in all cases with linear or linear branching calcifications. In amorphous microcalcifications, the characteristics of background echogenicity and the presence or absence of a nodal component in the gray scale mode had a much greater influence on the appearance of the twinkle effect in the normal B-mode, whereas in the B-flow mode, these characteristics did not have a decisive effect on the appearance of a flickering artifact (p=0.8). The density of distribution of microcalcifications, the size of calcifications, the final pathomorphology, mammography characteristics, the background environment during ultrasound by the presence or absence of nodular formation and anechoic zones, did not affect the appearance of a bright flash in the B-flow mode.DISCUSSION: The density of calcification distribution was not decisive for the appearance of a shimmering artifact in the B-flow mode. The flicker artifact is recorded both in grouped microcalcifications and in single ones. B-flow can help to detect calcifications that are not visible in the usual B-flow mode due to the lack of pronounced tissue contrast. But this artifact cannot be used to differentiate between benign and malignant processes.CONCLUSION: The B-flow technique is promising for clarifying the twinkle artifact in the detected microcalcifications on the mammogram, which could potentially increase the incidence of ultrasound-guided trephine biopsies by detecting more areas with microcalcification accumulations.

Application of the mineral-binding protein fetuin-A for the detection of calcified lesions.

Rationale: Calcium plays an essential role in the biology of vertebrates. Calcium content in body fluids is maintained within a narrow physiologic range by feedback control. Phosphate is equally important for metabolism and is likewise controlled, albeit over a wider range. This results in a nearly supersaturated state of calcium phosphate in body liquids driving mineral precipitation in soft tissues, which is actively prevented by calcification inhibitors. The hepatic plasma protein fetuin-A is a circulating mineralization inhibitor regulating calcium phosphate crystal growth and calcified matrix metabolism. Ectopic mineralization is associated with many pathological conditions aggravating their outcome. Current diagnostic methods lack sensitivity towards microcalcifications representing the initial stages of the process. Given the irreversibility of established calcifications, novel diagnostic tools capable of detecting nascent calcium phosphate deposits are highly desirable. Methods: We designed fluorescent fusion proteins consisting of fetuin-A coupled to a green or red fluorescent protein derivate, mEmerald or mRuby3, respectively. The proteins were expressed in mammalian cell lines. Sequence optimization resolved folding issues and increased sensitivity of mineral binding. Chimeric proteins were tested for their ability to detect calcifications in cell cultures and tissue sections retrieved from calcification-prone mice. Results: We employed novel genetically labeled fetuin-A-based fluorescent proteins for the detection of ectopic calcifications. We show that fetuin-A-based imaging agents are non-toxic and suitable for live imaging of microcalcifications beyond the detection limit of conventional staining techniques. The ability of fetuin-A to preferentially bind nascent calcium phosphate crystals allowed the resolution of histopathological detail of early kidney damage that went previously undetected. Endogenous expression of fetuin-A fluorescent fusion proteins allowed extended live imaging of calcifying cells with unprecedented sensitivity and specificity. Conclusion: Ectopic microcalcifications represent a major clinical concern lacking effective diagnostic and treatment options. In this paper, we describe novel highly sensitive fetuin-A-based fluorescent probes for imaging microcalcifications. We show that fusion proteins consisting of a fetuin-A mineral binding moiety and a fluorescent protein are superior to the routine methods for detecting calcifications. They also surpass in continuous live cell imaging the chemically fluorescence labeled fetuin-A, which we established previously.

Detection and classification of microcalcifications in mammograms images using difference filter and Yolov4 deep learning model

In this study, we focus on increasing the visibility of microcalcifications (MCs) in mammogram images by means of the difference filter and classifying the visibility-increased MCs by using Yolov4 deep learning model. The same classification experiments are reperformed for also the widely used Faster R-CNN deep learning model to compare with the proposed approach. For this aim, the difference filter is applied to the sections taken from normal and abnormal labeled mammogram images, and the filtered images are used as inputs to Yolov4 and Faster R-CNN models in order to classify as normal and abnormal. In order to show the contribution of the difference filter to the classification success, the experiments are reimplemented without using the difference filter. The difference filter based on the neighborhood relations of the image pixels significantly improves the classification success ratios of the classifier models used in the study since it increases especially the visibility of the rounded edges and makes microcalcifications in the image more prominent. As a result, the experiments show that the use of deep learning models together with the difference filter contributes significantly to the classification success. Finally, this study gives rise to the idea that it can greatly contribute to studies reading of the mammograms with MCs (abnormal) highlighted by the use of difference filter.

Visualizing microcalcifications in lumpectomy specimens: an exploration into the clinical potential of carbon nanotube-enabled stationary digital breast tomosynthesis

Purpose: To assess the visibility of microcalcifications in images generated by a first-generation carbon-nanotube (CNT)-enabled stationary digital breast tomosynthesis (sDBT) device, using magnified 2D mammography and conventional, moving-source DBT as references for comparison. Methods: Lumpectomy specimens were imaged by magnified mammography and two 3D mammography approaches, including sDBT and moving-source DBT. The planar size of individual microcalcifications was measured in the reconstructed image stacks of sDBT and moving-source DBT and compared to the magnified mammography image. An artifact spread function (ASF) was used to assess the depth dimensions of the microcalcifications displayed through the reconstructed image stacks. Breast-imaging specialists rated their preference for one imaging modality over another when interpreting microcalcifications in the magnified mammography image and synthetic slab images from sDBT and moving-source DBT. Results: The planar size of individual microcalcifications was similar in images generated by sDBT and moving-source DBT when the sDBT projections were binned to match the pixel size used by the moving-source DBT system. However, the unique structure of sDBT allowed for a wider-angle span of projection views and operation of the detector in full-resolution mode without significantly compromising the scan time. In this configuration, the planar sizes of individual microcalcifications displayed by sDBT was more similar to magnified mammography than moving-source DBT, and the microcalcifications had a narrower ASF through depth. Readers preferred sDBT over moving-source DBT when assessing microcalcifications in synthetic slab images, although magnified mammography was rated highest overall. Conclusions: The sDBT system displayed microcalcifications as well as conventional, moving-source DBT when the effective pixel size of the detector was matched. However, with the detector in its full-resolution mode, sDBT displayed microcalcifications with greater clarity. Readers still preferred images generated by magnified mammography over both 3D mammography approaches. This finding is guiding continued hardware and software development to optimize the sDBT technology.

Microcalcified Hepatic Metastases Incidentally Detected on F-18 NaF PET/CT in a Patient with Prostate Cancer.

F-18 NaF PET/CT evaluation has gained importance in recent years. Achievements from F-18 NaF PET/CT are: higher sensitivity of positron imaging, higher target background ratio with higher tracer accumulation in bone hydroxyapatite and higher specificity through CT correlation. These properties have also given directions to new research fields based on imaging microcalcifications, very recently. A limited number of cases have reported the F-18 NaF uptake in macrocalcified soft tissue metastases. Although the presence of microcalcification was not proved; accumulation of F-18 NaF in the metastatic brain lesion with no visible calcification on the CT, in a patient with ductal breast carcinoma has also been reported. Herein we present a patient with microcalcified hepatic metastasis of prostate cancer incidentally detected on F-18 NaF PET/CT which was confirmed with histochemical staining.

Maximum-likelihood estimation of scatter components algorithm for x-ray coherent scatter computed tomography of the breast

Coherent scatter computed tomography (CSCT) is a reconstructive x-ray imaging technique that yields the spatially resolved coherent-scatter cross section of the investigated object revealing structural information of tissue under investigation. In the original CSCT proposals the reconstruction of images from coherently scattered x-rays is done at each scattering angle separately using analytic reconstruction. In this work we develop a maximum likelihood estimation of scatter components algorithm (ML-ESCA) that iteratively reconstructs images using a few material component basis functions from coherent scatter projection data. The proposed algorithm combines the measured scatter data at different angles into one reconstruction equation with only a few component images. Also, it accounts for data acquisition statistics and physics, modeling effects such as polychromatic energy spectrum and detector response function. We test the algorithm with simulated projection data obtained with a pencil beam setup using a new version of MC-GPU code, a Graphical Processing Unit version of PENELOPE Monte Carlo particle transport simulation code, that incorporates an improved model of x-ray coherent scattering using experimentally measured molecular interference functions. The results obtained for breast imaging phantoms using adipose and glandular tissue cross sections show that the new algorithm can separate imaging data into basic adipose and water components at radiation doses comparable with Breast Computed Tomography. Simulation results also show the potential for imaging microcalcifications. Overall, the component images obtained with ML-ESCA algorithm have a less noisy appearance than the images obtained with the conventional filtered back projection algorithm for each individual scattering angle. An optimization study for x-ray energy range selection for breast CSCT is also presented.