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Purpose: Low levels of ghosting are found during quality control of digital mammography (DM). In digital breast tomosynthesis (DBT) mode, the x-ray detector is not cleared during the series of exposures potentially leading to ghosting issues. Methods: The ghosting image factor (GIF) was calculated for systems from three manufacturers as follows. A 45 mm thick polymethyl methacrylate (PMMA) block covering half the detector was imaged, followed by the PMMA block plus 0.1 mm thick aluminium sheet centred on the block, this time positioned to fully cover the detector. This was undertaken for (1) DM and (2) between separate DBT scans. Inter-projection ghosting (3) was measured by moving the PMMA block from covering half the detector to covering the whole detector after the first projection. In method (4), a 3 mm thick aluminium plate with a 0.1 mm thick aluminium sheet on top was placed on the compression paddle at 100 mm above the breast covering half of the detector. Results: The GIF measured via test (1) and (2) was lower than the 0.3 tolerance set in the European guidelines for DM, however higher values were found for one system in DBT mode. Test 3, inter-projection GIF values were between 0.08 and 0.89, mostly above 0.3. Test 4 was a practical method and gave larger GIF values of between 1.07 and 8.01. Conclusions Ghosting factors measured between projections are considerably higher than the GIF measured between separate DBT scans. We propose a simple method using an aluminium plate to estimate the GIF.

Purpose The present study aimed to explore the use of herbal products among a sample of Italian pregnant women and the possible influence of herbal consumption on pregnancy outcome. Methods The study was conducted over a 10-month period (2 days a week, from January to October 2009) at the Maternity wards of Padua and Rovereto Hospital. Data were collected through a face-to-face interview on the basis of a prestructured questionnaire including socio-demographic characteristics of the enrolled subjects, specific questions on herbal use, information about pregnancy and newborn. Results In total, 392 interviews were considered. One hundred and nine out of 392 women (27.8%) reported to have been taking one or more herbal products during pregnancy, in the 36.7% of cases throughout all pregnancy. The most frequently herbs taken by interviewees were chamomile, licorice, fennel, aloe, valerian, echinacea, almond oil, propolis, and cranberry. Four out of 109 women (3.7%) reported side-effects: constipation after a tisane containing a mix of herbs, rash and itching after local application of aloe or almond oil. The decision to use herbal products was mainly based on personal judgement and on the conviction that these natural substances would be safer than traditional medicines. Users were more often affected by morbidities pregnancy-related and their neonates were more frequently small for their gestational age. An higher incidence of threatening miscarriages and preterm labours was observed among regular users of chamomile and licorice. Conclusions This research underlines that the use of herbal products during pregnancy is common among Italian women, not always appropriate and in some cases potentially harmful. Copyright © 2010 John Wiley & Sons, Ltd.

Threshold contrast visibility measurements are used in mammography to assess image quality. The CDMAM contrast detail phantom version 3.4 was used to set the European standards for quality assurance in digital mammography. As such, the phantom has been widely used to assess the threshold contrast of clinical mammography equipment across Ireland. Recently an updated version of the phantom, version 4.0, was released. The CDMAM 4.0 consists of a new layout with more disc diameters and thicknesses than its predecessor. The new version was created with the aim to be more closely adopted to the image quality found in modern mammography systems and to reduce the variability across individual phantoms. This study compares the sensitivity of the two versions of the CDMAM phantom across a range of mammography systems at clinical settings. Contrast detail measurements were taken using the different phantoms on four different makes of digital mammography equipment and images were analysed using CDMAM Analysis v2.1.0 software package. Here we present resuts of a comparison in threshold contrast sensitivity between the two versions of the phantom.

To demonstrate how a PACS integrated dose monitoring system, Gray Detector, can help to monitor client dose in a breast screening program, ultimately facilitating the optimisation of acquisition parameters in order to enhance image quality and minimise the dose BreastCheck, The National Breast Screening Program evaluated the RIS-PACS integrated dose monitoring system Gray Detector. For each projection of a screening examination, the displayed average glandular dose (AGD), compression force, compressed breast thickness, selected automatic exposure control (AEC) mode, kV and mAs were recorded. Preliminary data have been collected for three months which have enabled comparison of a number of mammography system types and comparison between systems of the same type, in terms of dose, compression force and other key characteristic parameters. Patient dose data collected so far confirm the results of our annual dose survey. All the mammography systems were monitored on a daily basis. The daily presentation of data provides a useful QA tool, highlighting potential problems with individual mammography systems and illustrating the dependency of client dose on other clinical parameters such as compressed breast thickness and compression force. This will enable standardisation of the acquisition technique in order to reduce client dose and optimize the image quality. A summary of these preliminary results will be presented. The Gray Detector software provides useful functionality for monitoring key parameters of the breast screening examination including in particular, the AGD which may be used to monitor and improve clinical quality performance in the screening program.

Getting to grips with quantitative image quality measurements for QA of digital mammography (DM) systems Current European Guidelines for the quality assurance of digital mammography systems recommend and outline methods for the quantitative assessment of image quality (IQ). Recommended metrics include the pre-sampled modulation transfer function (MTF), normalized noise power spectrum (NNPS) and the detective quantum efficiency (DQE). The methods described are well established and have been successfully applied to the evaluation of digital mammography systems for QA purposes. At BreastCheck, we have substantial experience in the use of subjective and semi-quantitative test objects such as the CDMAM contrast-detail test object. As an adjunct to these methods, we have integrated quantitative methods to the routine QA programme. We describe the implementation of quantitative image quality metrics and examine the stability of these parameters over time, the ease with which they might be included in a routine QA programme and discuss some of the problems encountered during the implementation. We have demonstrated good comparison between the MTF values obtained from the QA surveys performed on BreastCheck DM systems with results for similar systems published in the literature. We have also found the long-term reproducibility of MTF, NNPS and DQE measurements values (COV∼3%–5%) are as good as quoted in the literature. We expect that the stability of these IQ measurements will facilitate more accurate monitoring of changes in imaging system performance than can be currently achieved using subjective image quality parameters. Consequently, deteriorating IQ performance may be flagged earlier.

The present study aimed to explore the use of herbal products among a sample of Italian pregnant women and the possible influence of herbal consumption on pregnancy outcome.The study was conducted over a 10-month period (2 days a week, from January to October 2009) at the Maternity wards of Padua and Rovereto Hospital. Data were collected through a face-to-face interview on the basis of a prestructured questionnaire including socio-demographic characteristics of the enrolled subjects, specific questions on herbal use, information about pregnancy and newborn.In total, 392 interviews were considered. One hundred and nine out of 392 women (27.8%) reported to have been taking one or more herbal products during pregnancy, in the 36.7% of cases throughout all pregnancy. The most frequently herbs taken by interviewees were chamomile, licorice, fennel, aloe, valerian, echinacea, almond oil, propolis, and cranberry. Four out of 109 women (3.7%) reported side-effects: constipation after a tisane containing a mix of herbs, rash and itching after local application of aloe or almond oil. The decision to use herbal products was mainly based on personal judgement and on the conviction that these natural substances would be safer than traditional medicines. Users were more often affected by morbidities pregnancy-related and their neonates were more frequently small for their gestational age. An higher incidence of threatening miscarriages and preterm labours was observed among regular users of chamomile and licorice.This research underlines that the use of herbal products during pregnancy is common among Italian women, not always appropriate and in some cases potentially harmful.

For almost 3 years, Radiologists and Physicists from Padova and Ferrara Universities have collaborated together, with the aim of collecting and comparing experimental data useful to define the most significant parameters for quality controls in digital mammography. Successively, radiologists and physicists working in other sites where a digital mammography unit was installed joined the work-group.In this study we report the results obtained from measurements of linearity, uniformity, short- and long-term reproducibility, AEC stability performed on 5 digital equipment by using a simple test object. X-ray beam quality and tube yield were preliminarily checked in such a way that possible uncertainties of digital system responses could be separated from those due to differences among X-ray tubes.Results showed that the equipment considered, comparable in terms of both beam quality (HVL) and tube yield, always displayed linear response and reproducibility errors lower than 5%. Uniformity was very good and the grey level compensation as a function of exposure parameters remained within 5%. Differences in choice of parameters by exposure control system (AOP) were emphasised, especially for crossing between track/filter combinations (from Mo/Mo to Mo/Rh and from Mo/Rh to Rh/Rh); those differences were attributed to the +/-2 mm tolerance of breast thickness measurement (mechanically obtained) greater than the AOP tolerance (+/-1 mm).Obtained results can be useful, as comparison and reference values, for users employing a digital mammography unit of the same kind reported in this paper. Moreover, the same results could be used as "orientation" also by other users having different digital mammography technologies, whose operation should be nevertheless specifically studied and understood in order to find the most useful parameters for quality controls. The acquired experience clearly showed us that years of investigations will be necessary in order to be able to write reliable protocols. This should induce people to contemplate the necessity of not improvising "theoretical" protocols, that are unreliable and dangerous for their negative clinical implications.

Mammography is currently considered the best tool for the detection of breast cancer, pathology with a rate of incidence in constant increase. To produce the radiological picture a screen film combination is conventionally used. One of the inherent limitations of screen- film combination is the fact that the detection, display and storage processes are one and the same, making it impossible to separately optimize each stage. These limitations can be overcome with digital systems. In this work we evaluate the main characteristics of digital detectors available on the market and we compare the performance of digital and conventional systems. Digital mammography, due to the possibility to process images, offers many potential advantages, among these the possibility to introduce the dual-energy technique which employs the composition of two digital images obtained with two different energies to enhance the inherent contrast of pathologies by removing the uniform background. This technique was previously tested by using synchrotron monochromatic beam and a digital detector, and then the Senographe 2000D full-field digital system manufactured by GE Medical Systems. In this work we present preliminary results and the future applications of this technique.