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18 result(s) for "Fallenberg, Eva Maria"
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Assessment of coronary artery stents using 16-slice MDCT angiography: evaluation of a dedicated reconstruction kernel and a noise reduction filter
To compare the effect of different reconstruction kernels and a noise-reducing postprocessing filter on the delineation of coronary artery stents in 16-slice CT-angiography. Ten patients with coronary stents (seven LAD, five RCX and three RCA) were examined with a 16-slice MDCT using standard acquisition parameters. Images were reconstructed using a medium soft (B30f) and a dedicated, edge-enhancing kernel (B46f). Additional postprocessing with an edge-preserving filter was performed on B46f images to reduce the image noise. In multiplanar reformations (MPRs) along and perpendicular to the stent axis, intraluminal attenuation values and the visible lumen diameter were measured. Image noise was measured in the subcutaneous fat using a region of interest (ROI) technique. Arterial enhancement in the aorta was 275.1 HU. Attenuation in the stent lumen was 390.4, 340.0 and 346.8 HU in MPRs derived from B30f, original B46 and postprocessed B46f images. The mean noise level was 20.4, 35.0 and 24.9 HU respectively. The visible lumen diameter was significantly greater in B46f and postprocessed B46f images (2.17 and 2.16 mm), compared to 1.93 mm in B30f images (p<0.01). Edge-enhancing reconstruction kernels increase the visible stent lumen, but also increase image noise. Dedicated postprocessing filters can reduce the introduced noise without a loss of spatial resolution.
An update on multimodal imaging strategies for nipple discharge: from detection to decision
Nipple discharge affects over 80% of women at some point in their lives, with malignancy detected in up to 23% of cases. This review highlights the shift from traditional surgical approaches to advanced imaging techniques, which enhance diagnostic accuracy and reduce unnecessary procedures. Diagnosis begins with a thorough medical history and physical examination to assess the need for imaging. Physiological nipple discharge, which is bilateral, multiductal, and non-spontaneous, typically requires no imaging. Conversely, pathological nipple discharge (PND), characteristically unilateral, uniductal, and spontaneous, requires imaging to rule out malignancy. Bloody PND is frequently associated with breast cancer, and up to 12% of non-bloody PND cases also involve malignancy. For women over 40 years, the first-line imaging modality is full-field digital mammography (FFDM) or digital breast tomosynthesis (DBT), usually combined with ultrasound (US). Men with PND undergo FFDM/DBT starting at age 25 years due to their higher risk of breast cancer. For women aged 30–39 years, US is the first assessment tool, with FFDM/DBT added, if necessary, while US is preferred for younger women and men. When initial imaging is negative or inconclusive, magnetic resonance imaging (MRI) is useful, often replacing galactography. With its high sensitivity and negative predictive value of almost 100%, a negative MRI can often obviate the need for surgery. Contrast-enhanced mammography (CEM) offers a viable alternative when MRI is not feasible. Although invasive, ductoscopy helps identify patients who may not require duct excision. This review consolidates the latest evidence and proposes an updated diagnostic algorithm for managing PND effectively. Critical relevance statement Effective management of nipple discharge requires recognising when imaging tests are needed and selecting the most appropriate diagnostic technique to rule out malignancy and avoid unnecessary interventions. Key Points First-line imaging for pathological nipple discharge (PND) assessment includes ultrasound and mammography. MRI is recommended for patients with PND and negative conventional imaging. A negative MRI is sufficient to justify surveillance rather than surgery. Contrast-enhanced mammography (CEM) is an alternative when MRI is unavailable or contraindicated. Graphical Abstract
The effect of dynamic, semi-rigid implants on the range of motion of lumbar motion segments after decompression
Undercutting decompression is a common surgical procedure for the therapy of lumbar spinal canal stenosis. Segmental instability, due to segmental degeneration or iatrogenic decompression is a typical problem that is clinically addressed by fusion, or more recently by semi-rigid stabilization devices. The objective of this experimental biomechanical study was to investigate the influence of spinal decompression alone, as well as in conjunction with two semi-rigid stabilizing implants (Wallis, Dynesys®) on the range of motion (ROM) of lumbar spine segments. A total of 21 fresh-frozen human lumbar spine motion segments were obtained. Range of motion and neutral zone (NZ) were measured in flexion-extension (FE), lateral bending (LAT) and axial rotation (ROT) for each motion segment under four conditions: (1) with all stabilizing structures intact (PHY), (2) after bilateral undercutting decompression (UDC), (3) after additional implantation of Wallis (UDC-W) and (4) after removal of Wallis and subsequent implantation of Dynesys® (UDC-D). Measurements were performed using a sensor-guided industrial robot in a pure-moment-loading mode. Range of motion was defined as the angle covered between loadings of −5 and +5 Nm during the last of three applied motion cycles. Untreated physiologic segments showed the following mean ROM: FE 6.6°, LAT 7.4°, ROT 3.9°. After decompression, a significant increase of ROM was observed: 26% FE, 6% LAT, 12% ROT. After additional implantation of a semi-rigid device, a decrease in ROM compared to the situation after decompression alone was observed with a reduction of 66 and 75% in FE, 6 and 70% in LAT, and 5 and 22% in ROT being observed for the Wallis and Dynesys®, respectively. When the flexion and extension contribution to ROM was separated, the Wallis implant restricted extension by 69% and flexion by 62%, the Dynesys® by 73 and 75%, respectively. Compared to the intact status, instrumentation following decompression led to a ROM reduction of 58 and 68% in FE, 1 and 68% in LAT, −6 and 13% in ROT, 61 and 65% in extension and 54 and 70% in flexion for Wallis and Dynesys®. The effect of the implants on NZ corresponded to that on ROM. In conclusion, implantation of the Wallis and Dynesys® devices following decompression leads to a restriction of ROM in all motion planes investigated. Flexion–extension is most affected by both implants. The Dynesys® implant leads to an additional strong restriction in lateral bending. Rotation is only mildly affected by both implants. Wallis and Dynesys® restrict not only isolated extension, but also flexion. These biomechanical results support the hypothesis that postoperatively, the semi-rigid implants provide a primary stabilizing function directly. Whether they can improve the clinical outcome must still be verified in prospective clinical investigations.
Second International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions)
PurposeThe second International Consensus Conference on B3 lesions was held in Zurich, Switzerland, in March 2018, organized by the International Breast Ultrasound School to re-evaluate the consensus recommendations.MethodsThis study (1) evaluated how management recommendations of the first Zurich Consensus Conference of 2016 on B3 lesions had influenced daily practice and (2) reviewed current literature towards recommendations to biopsy.ResultsIn 2018, the consensus recommendations for management of B3 lesions remained almost unchanged: For flat epithelial atypia (FEA), classical lobular neoplasia (LN), papillary lesions (PL) and radial scars (RS) diagnosed on core-needle biopsy (CNB) or vacuum-assisted biopsy (VAB), excision by VAB in preference to open surgery, and for atypical ductal hyperplasia (ADH) and phyllodes tumors (PT) diagnosed at VAB or CNB, first-line open surgical excision (OE) with follow-up surveillance imaging for 5 years. Analyzing the Database of the Swiss Minimally Invasive Breast Biopsies (MIBB) with more than 30,000 procedures recorded, there was a significant increase in recommending more frequent surveillance of LN [65% in 2018 vs. 51% in 2016 (p = 0.004)], FEA (72% in 2018 vs. 62% in 2016 (p = 0.005)), and PL [(76% in 2018 vs. 70% in 2016 (p = 0.04)] diagnosed on VAB. A trend to more frequent surveillance was also noted also for RS [77% in 2018 vs. 67% in 2016 (p = 0.07)].ConclusionsMinimally invasive management of B3 lesions (except ADH and PT) with VAB continues to be appropriate as an alternative to first-line OE in most cases, but with more frequent surveillance, especially for LN.
Third International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions)
The heterogeneous group of B3 lesions in the breast harbors lesions with different malignant potential and progression risk. As several studies about B3 lesions have been published since the last Consensus in 2018, the 3rd International Consensus Conference discussed the six most relevant B3 lesions (atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), radial scar (RS), papillary lesions (PL) without atypia, and phyllodes tumors (PT)) and made recommendations for diagnostic and therapeutic approaches. Following a presentation of current data of each B3 lesion, the international and interdisciplinary panel of 33 specialists and key opinion leaders voted on the recommendations for further management after core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). In case of B3 lesion diagnosis on CNB, OE was recommended in ADH and PT, whereas in the other B3 lesions, vacuum-assisted excision was considered an equivalent alternative to OE. In ADH, most panelists (76%) recommended an open excision (OE) after diagnosis on VAB, whereas observation after a complete VAB-removal on imaging was accepted by 34%. In LN, the majority of the panel (90%) preferred observation following complete VAB-removal. Results were similar in RS (82%), PL (100%), and FEA (100%). In benign PT, a slim majority (55%) also recommended an observation after a complete VAB-removal. VAB with subsequent active surveillance can replace an open surgical intervention for most B3 lesions (RS, FEA, PL, PT, and LN). Compared to previous recommendations, there is an increasing trend to a de-escalating strategy in classical LN. Due to the higher risk of upgrade into malignancy, OE remains the preferred approach after the diagnosis of ADH.
Multi-detector row computed tomography of the heart: does a multi-segment reconstruction algorithm improve left ventricular volume measurements?
A multi-segment cardiac image reconstruction algorithm in multi-detector row computed tomography (MDCT) was evaluated regarding temporal resolution and determination of left ventricular (LV) volumes and global LV function. MDCT and cine magnetic resonance (CMR) imaging were performed in 12 patients with known or suspected coronary artery disease. Patients gave informed written consent for the MDCT and the CMR exam. MDCT data were reconstructed using the standard adaptive cardiac volume (ACV) algorithm as well as a multi-segment algorithm utilizing data from three, five and seven rotations. LV end-diastolic (LV-EDV) and end-systolic volumes and ejection fraction (LV-EF) were determined from short-axis image reformations and compared to CMR data. Mean temporal resolution achieved was 192+/-24 ms using the ACV algorithm and improved significantly utilizing the three, five and seven data segments to 139+/-12, 113+/-13 and 96+/-11 ms (P<0.001 for each). Mean LV-EDV was without significant differences using the ACV algorithm, the multi-segment approach and CMR imaging. Despite improved temporal resolution with multi-segment image reconstruction, end-systolic volumes were less accurately measured (mean differences 3.9+/-11.8 ml to 8.1+/-13.9 ml), resulting in a consistent underestimation of LV-EF by 2.3-5.4% in comparison to CMR imaging (Bland-Altman analysis). Multi-segment image reconstruction improves temporal resolution compared to the standard ACV algorithm, but this does not result in a benefit for determination of LV volume and function.
A survey by the European Society of Breast Imaging on radiologists’ preferences regarding quality assurance measures of image interpretation in screening and diagnostic mammography
Objectives Quality assurance (QA) of image interpretation plays a key role in screening and diagnostic mammography, maintaining minimum standards and supporting continuous improvement in interpreting images. However, the QA structure across Europe shows considerable variation. The European Society of Breast Imaging (EUSOBI) conducted a survey among the members to collect information on radiologists’ preferences regarding QA measures in mammography. Materials and methods An anonymous online survey consisting of 25 questions was distributed to all EUSOBI members and national breast radiology bodies in Europe. The questions were designed to collect demographic characteristics, information on responders’ mammography workload and data about QA measures currently used in their country. Data was analysed using descriptive statistical analysis, the χ 2 test, linear regression, and Durbin-Watson statistic test. Results In total, 251 breast radiologists from 34 countries completed the survey. Most respondents were providing both screening and symptomatic services (137/251, 54.6%), working in an academic hospital (85/251, 33.9%) and reading 1000–4999 cases per year (109/251, 43.4%). More than half of them (133/251, 53%) had established QA measures in their workplace. Although less than one-third (71/251, 28.3%) had to participate in regular performance testing, the vast majority (190/251, 75.7%) agreed that a mandatory test would be helpful to improve their skills. Conclusion QA measures were in place for more than half of the respondents working in screening and diagnostic mammography to evaluate their breast imaging performance. Although there were substantial differences between countries, the importance of having QA in the workplace and implemented was widely acknowledged by radiologists. Clinical relevance statement Although several quality assurance (QA) measures of image interpretation are recommended by European bodies or national organisations, the QA in mammography is quite heterogenous between countries and reporting settings, and not always actively implemented across Europe. Key Points The first survey that presents radiologists’ preferences regarding QA measures of image interpretation in mammography. Quality assurance measures in the workplace are better-established for breast screening compared to diagnostic mammography. Radiologists consider that performance tests would help to improve their mammography interpretation skills.
Contrast-enhanced spectral mammography: Does mammography provide additional clinical benefits or can some radiation exposure be avoided?
The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) with mammography (MG) and combined CESM + MG in terms of detection and size estimation of histologically proven breast cancers in order to assess the potential to reduce radiation exposure. A total of 118 patients underwent MG and CESM and had final histological results. CESM was performed as a bilateral examination starting 2 min after injection of iodinated contrast medium. Three independent blinded radiologists read the CESM, MG, and CESM + MG images with an interval of at least 4 weeks to avoid case memorization. Sensitivity and size measurement correlation and differences were calculated, average glandular dose (AGD) levels were compared, and breast densities were reported. Fisher’s exact and Wilcoxon tests were performed. A total of 107 imaging pairs were available for analysis. Densities were ACR1: 2, ACR2: 45, ACR3: 42, and ACR4: 18. Mean AGD was 1.89 mGy for CESM alone, 1.78 mGy for MG, and 3.67 mGy for the combination. In very dense breasts, AGD of CESM was significantly lower than MG. Sensitivity across readers was 77.9 % for MG alone, 94.7 % for CESM, and 95 % for CESM + MG. Average tumor size measurement error compared to postsurgical pathology was −0.6 mm for MG, +0.6 mm for CESM, and +4.5 mm for CESM + MG ( p  < 0.001 for CESM + MG vs. both modalities). CESM alone has the same sensitivity and better size assessment as CESM + MG and was significantly better than MG with only 6.2 % increase in AGD. The combination of CESM + MG led to systematic size overestimation. When a CESM examination is planned, additional MG can be avoided, with the possibility of saving up to 61 % of radiation dose, especially in patients with dense breasts.
Assessing breast density using the chemical-shift encoding-based proton density fat fraction in 3-T MRI
Objectives There is a clinical need for a non-ionizing, quantitative assessment of breast density, as one of the strongest independent risk factors for breast cancer. This study aims to establish proton density fat fraction (PDFF) as a quantitative biomarker for fat tissue concentration in breast MRI and correlate mean breast PDFF to mammography. Methods In this retrospective study, 193 women were routinely subjected to 3-T MRI using a six-echo chemical shift encoding-based water-fat sequence. Water-fat separation was based on a signal model accounting for a single T 2 * decay and a pre-calibrated 7-peak fat spectrum resulting in volumetric fat-only, water-only images, PDFF- and T 2 *-values. After semi-automated breast segmentation, PDFF and T 2 * values were determined for the entire breast and fibroglandular tissue. The mammographic and MRI-based breast density was classified by visual estimation using the American College of Radiology Breast Imaging Reporting and Data System categories (ACR A-D). Results The PDFF negatively correlated with mammographic and MRI breast density measurements (Spearman rho: −0.74, p < .001) and revealed a significant distinction between all four ACR categories. Mean T 2 * of the fibroglandular tissue correlated with increasing ACR categories (Spearman rho: 0.34, p < .001). The PDFF of the fibroglandular tissue showed a correlation with age (Pearson rho: 0.56, p = .03). Conclusion The proposed breast PDFF as an automated tissue fat concentration measurement is comparable with mammographic breast density estimations. Therefore, it is a promising approach to an accurate, user-independent, and non-ionizing breast density assessment that could be easily incorporated into clinical routine breast MRI exams. Key Points • The proposed PDFF strongly negatively correlates with visually determined mammographic and MRI-based breast density estimations and therefore allows for an accurate, non-ionizing, and user-independent breast density measurement . • In combination with T2*, the PDFF can be used to track structural alterations in the composition of breast tissue for an individualized risk assessment for breast cancer .
Use of contrast-enhanced mammography for diagnosis of breast cancer
Contrast-enhanced mammography (CEM) is an imaging method that is able to improve visualization of intramammary tumors after peripheral venous administration of an iodine-containing contrast medium (ICM). The current significance of CEM is discussed. Studies were able to show an advantage of CEM in the diagnosis of breast cancer compared to mammography, especially for women with dense breasts. Indications for CEM currently depend on the availability of magnetic resonance imaging (MRI). If MRI is available, CEM is indicated in those cases when MRI cannot be performed. Use of CEM for breast cancer screening is currently viewed critically. This view can change when results and updated assessments of large CEM studies in Europe and USA become available. Patients must be informed about the use of an ICM. As ICM administration for CEM is carried out in a similar manner to established imaging methods, the authors expect the use of ICM for CEM to be unproblematic as long as general contraindications are adhered to. In the future, CEM could have greater importance for the diagnosis of breast cancer, as this imaging method has diagnostic advantages compared to conventional mammography. A great advantage of CEM is its availability. For those who use breast MRI, CEM is helpful when MRI is not feasible due to contraindications or other reasons.