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Diffusion-weighted imaging (DWI) of the breast provides additional contrast information in breast magnetic resonance imaging (MRI). The DWI procedure can easily be implemented in the routine breast MRI protocol with little time expenditure regarding image acquisition and evaluation. Evaluation of the DW images can be performed with or without the routine breast MRI sequences (T2w and T1w with contrast material) but evaluation in combination with the routine program is highly recommended. Objective analysis of the tissue diffusion can be achieved by calculating the apparent diffusion coefficient (ADC) value with the scanner software. The choice of the DW sequence, evaluation and determination of the ADC threshold to differentiate between benign and malignant lesions should be scanner adapted. The use of DW imaging qualifies for routine use regarding the differentiation between malignant and benign breast lesions. Non-mass-like lesions and monitoring neoadjuvant chemotherapy can also be evaluated with DW sequences. The benefit of the additional information from DW-MR mammography to characterize non-mass-like lesions and in the course of neoadjuvant chemotherapy remains unclear to date.

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 (p0.001). Considering the diagnostic accuracy, the new system (detector: 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.

The article describes an experimental phantom study of a system for digital full field mammography with a new digital detector with a double plate of pure selenium.The experiments were carried out with the new full field digital mammography system Amulet from FujiFilm. This system has a new detector (18×24 cm(2)) on the basis of highly purified amorphous selenium (a-Se) with a pixel size of 50 µm. The x-rays are converted into electric signals in the first plate which are read into the second plate with the help of an optical switch and demonstrated in the form of an image. In this way a better pixel size/volume and signal-to-noise ratio should be achieved. The object of the investigation was the Wisconsin Mammographic Random Phantom, Model 152 A (Technical Performance Mo/Mo, 28 kV, 100 mAs). Five investigators with different experiences in mammography each received three images on a monitor with different random positions of the simulated lesions in the phantom for assessment. The detection rates were compared under the same conditions with the results of two other full field digital mammography systems.The median detection rate for all images and investigators for the new doubled plated a-Se detector with optical switch was 98.7%. For both other systems with a-Si or and a-Se detectors the detection rate was 89.8% or 97.3%, respectively. There were no significant differences in the detection rate of the simulated breast lesions for all three systems considering the interobserver and intraobserver variation.The first phantom study for the detection of simulated breast lesions with the new full field digital mammography system Amulet demonstrates equivalent results with the other systems used in the clinical routine. The trend towards superiority of the new system has to be confirmed in further clinical studies.