Eva M. Fallenberg

Evaluation of global left ventricular myocardial function with electrocardiogram-gated multidetector computed tomography: comparison with magnetic resonance imaging.

Rationale and Objectives:Electrocardiogram-gated 3D volume data from multidetector computed tomography coronary angiography (MDCT-CA) enable image reconstruction in any phase of the cardiac cycle. The objective was to determine left ventricular (LV) function parameters by MDCT in comparison to cine magnetic resonance imaging (MRI). Methods:Thirty patients with known or suspected coronary artery disease (CAD) underwent MDCT-CA. From multiplanar reformations in short axis orientation end-diastolic and end-systolic LV volumes (LVEDV, LVESV) were determined to calculate LV stroke volume and ejection fraction (LVSV, LVEF) and compared with MRI measurements. Results:LVEDV (147 ± 27 mL) and LVESV (65 ± 22 mL) determined by MDCT correlated well to the respective MRI measurements (LVEDV 133 ± 27 mL, r = 0.80, P < 0.001; LVESV 48 ± 19 mL, r = 0.89, P < 0.001). LVSV (MDCT 82 ± 15 mL; MRI 85 ± 17 mL; r = 0.77, P < 0.001) and LVEF (MDCT 56 ± 9%; MRI 65 ± 8%; r = 0.85, P < 0.001) showed a good correlation as well. LVEF was significantly underestimated by MDCT (−8.5 ± 4.7%, P < 0.001). Conclusions:Initial experience in patients evaluated for CAD shows that spiral MDCT studies may provide LV functional data in good correlation to Cine MRI.

Dual-energy contrast-enhanced digital mammography: initial clinical results of a multireader, multicase study

IntroductionThe purpose of this study was to compare the diagnostic accuracy of dual-energy contrast-enhanced digital mammography (CEDM) as an adjunct to mammography (MX) ± ultrasonography (US) with the diagnostic accuracy of MX ± US alone.MethodsOne hundred ten consenting women with 148 breast lesions (84 malignant, 64 benign) underwent two-view dual-energy CEDM in addition to MX and US using a specially modified digital mammography system (Senographe DS, GE Healthcare). Reference standard was histology for 138 lesions and follow-up for 12 lesions. Six radiologists from 4 institutions interpreted the images using high-resolution softcopy workstations. Confidence of presence (5-point scale), probability of cancer (7-point scale), and BI-RADS scores were evaluated for each finding. Sensitivity, specificity and ROC curve areas were estimated for each reader and overall. Visibility of findings on MX ± CEDM and MX ± US was evaluated with a Likert scale.ResultsThe average per-lesion sensitivity across all readers was significantly higher for MX ± US ± CEDM than for MX ± US (0.78 vs. 0.71 using BIRADS, p = 0.006). All readers improved their clinical performance and the average area under the ROC curve was significantly superior for MX ± US ± CEDM than for MX ± US ((0.87 vs 0.83, p = 0.045). Finding visibility was similar or better on MX ± CEDM than MX ± US in 80% of cases.ConclusionsDual-energy contrast-enhanced digital mammography as an adjunct to MX ± US improves diagnostic accuracy compared to MX ± US alone. Addition of iodinated contrast agent to MX facilitates the visualization of breast lesions.

Evaluation of contrast-enhanced digital mammography.

PURPOSE The goal of this prospective study was to evaluate the possible diagnostic benefits of contrast-enhanced digital mammography (CEDM) over conventional mammography. MATERIALS AND METHODS Our analysis included data from 70 patients with a total of 80 lesions (30 malignant and 50 benign). A series of contrast-enhanced images was acquired from each patient using a modified imaging system (GE Senographe 2000D with copper filter) suitable for displaying iodine contrast medium. After the mask image had been taken, the contrast medium was administered using a dosage of 1ml/kg body weight at a rate of 4ml/s. Three contrast-enhanced images in the cranio-caudal projection plane were then captured at intervals of 60s. The mask image was logarithmically subtracted from the contrast-enhanced images. We performed a ROC analysis of diagnostic quality with three readers. RESULTS On average, 5.66 more malignant lesions were detected with the addition of digital dynamic contrast mammography versus conventional mammography alone. The sensitivity was increased from an average of 0.43 in conventional mammography to an average of 0.62 with contrast mammography. Even in dense breast parenchyma, the sensitivity increased from an average of 0.35-0.59. In the multi-reader-ROC analyses of all readers, the differences in the AUC with p=0.02 (BI-RADS) proved statistically significant in all cases. The Wilcoxon test showed that Readers I and II primarily used the CEDM to upgrade enhancing lesions to a higher BI-RADS category or a higher probability of malignancy. These two readers benefited most from the CEDM in the ROC analysis. CONCLUSION Overall, we conclude that the addition of dynamic digital subtraction mammography to conventional mammography can significantly improve diagnostic quality. The increased sensitivity is particularly pronounced in the case of dense breast tissue.

Breast MRI: EUSOBI recommendations for women's information.

AbstractThis paper summarizes information about breast MRI to be provided to women and referring physicians. After listing contraindications, procedure details are described, stressing the need for correct scheduling and not moving during the examination. The structured report including BI-RADS® categories and further actions after a breast MRI examination are discussed. Breast MRI is a very sensitive modality, significantly improving screening in high-risk women. It also has a role in clinical diagnosis, problem solving, and staging, impacting on patient management. However, it is not a perfect test, and occasionally breast cancers can be missed. Therefore, clinical and other imaging findings (from mammography/ultrasound) should also be considered. Conversely, MRI may detect lesions not visible on other imaging modalities turning out to be benign (false positives). These risks should be discussed with women before a breast MRI is requested/performed. Because breast MRI drawbacks depend upon the indication for the examination, basic information for the most important breast MRI indications is presented. Seventeen notes and five frequently asked questions formulated for use as direct communication to women are provided. The text was reviewed by Europa Donna–The European Breast Cancer Coalition to ensure that it can be easily understood by women undergoing MRI.Key Points• Information on breast MRI concerns advantages/disadvantages and preparation to the examination • Claustrophobia, implantable devices, allergic predisposition, and renal function should be checked • Before menopause, scheduling on day 7–14 of the cycle is preferred • During the examination, it is highly important that the patient keeps still • Availability of prior examinations improves accuracy of breast MRI interpretation

Flat epithelial atypia is a common subtype of B3 breast lesions and is associated with noninvasive cancer but not with invasive cancer in final excision histology

The biological behavior and the optimal management of benign breast lesions with uncertain malignant potential, the so-called B3 lesions, found in breast needle core biopsies is still under debate. We addressed this study to compare histologic findings in B3 needle core biopsies with final excision specimens to determine associated rates of malignancy. Consecutive needle core biopsies were performed in a 3-year period (January 1, 2006-December 31, 2008). Biopsies were image-guided (31 by ultrasound, 85 stereotactic vacuum-assisted, 6 unknown) for evaluation of breast abnormalities. We reviewed 122 needle core biopsies with B3 lesions of 91 symptomatic patients and 31 screen-detected women and compared the B3 histologic subtypes with the final excision histology. A total of 1845 needle core biopsies were performed and B3 lesions comprised 6.6% of all B categories. The most common histologic subtype in biopsies was flat epithelia atypia in 35.2%, followed by papillary lesions in 21% and atypical ductal hyperplasia in 20%. Reports on excision specimens were available in 66% (81 patients). Final excision histology was benign in 73 (90.2%) and malignant in 8 (9.8%) patients (2 invasive cancer, 6 ductal carcinoma in situ). Of all B3 subtypes, atypical ductal hyperplasia and flat epithelial atypia were associated with malignancy, whereas only atypical ductal hyperplasia was accompanied by invasive cancer. Of all lesions, flat epithelial atypia was most frequently found in excision specimens (18%). In our study, flat epithelial atypia and atypical ductal hyperplasia are common lesions of the B3 category in needle core biopsies of the breast. Both lesions are associated with malignancy, whereas only atypical ductal hyperplasia was related to invasive cancer. We conclude that an excision biopsy after diagnosis of flat epithelial atypia is recommended depending on clinical and radiologic findings.

Detection and classification of contrast-enhancing masses by a fully automatic computer-assisted diagnosis system for breast MRI

To evaluate a fully automatic computer‐assisted diagnosis (CAD) method for breast magnetic resonance imaging (MRI), which considered dynamic as well as morphologic parameters and linked those to descriptions laid down in the Breast Imaging Reporting and Data System (BI‐RADS) MRI atlas.

The position of the aorta relative to the spine before and after anterior instrumentation in right thoracic scoliosis.

Study Design. Preoperative magnetic resonance images (MRI) and postoperative axial computed tomography (CT) scans in 25 consecutive patients with idiopathic right thoracic adolescent scoliosis (AIS) and anterior correction and fusion with a dual rod system were analyzed in a prospective study. Objectives. Evaluation of the spatial relations between the vertebral body and the aorta and the relative migration of the aorta due to the anterior correction and instrumentation in right thoracic scoliosis patients. Summary of Background Data. In anterior scoliosis surgery, bicortical screw purchase is performed to increase pullout strength. However, impingement of the aorta due to excessive contralateral screw penetration has been reported, especially after endoscopic instrumentation. For a safe screw placement, knowledge of both the preoperative topographic relation of aorta and vertebral body and its changes due to surgical correction is crucial. Recent studies reported on a more lateral and posterior position of the aorta in AIS patients. However, there are hardly any data on the changes of the aortic position after anterior curve correction available in the current literature. Methods. All 25 patients underwent an identical anterior surgical technique with standard open approach and dual rod instrumentation of the primary curve. Preoperative MRI and postoperative sequential CT scans of 180 vertebrae were analyzed with respect to following parameters: vertebral body width and depth, diameter of the aorta, closest distance between aorta and the vertebral body, the aorta-vertebral angle, and the position of the aorta in relation to the spinal canal. Results. Before surgery, the aorta is positioned posterolaterally with an aorta-vertebral angle of between 78° and 92° (between T5 and T10). Between T11 and L2, the aorta is positioned more anteromedially with an aorta-vertebral angle from 62° (T11) to 16° (L2). After surgery, the aorta has migrated from a posterolateral to a more anteromedial position. This migration is maximal at the apex vertebra with an average change of the aorta-vertebral angle of 31.4°. Whereas the distance between the aorta and the vertebral body increases at the upper and lower fusion levels, the aorta moves significantly closer to the vertebral body at the curve apex due to surgical correction. In patients with thoracic hypokyphosis, the aorta is positioned significantly more posterior than in patients with hyperkyphosis. Conclusions. This MRI and CT based study of 25 patients with thoracic AIS treated by standard open dual rod and dual screw instrumentation demonstrates a migration of the aorta by 31° from a more posterolateral position before surgery to a more anteromedial position after surgery at the curve apex. Scoliosis surgeons should be aware of these changes; any excessive contralateral screw penetration must be avoided at any level.

Development of Low-Dose Photon-counting Contrast-enhanced Tomosynthesis with Spectral Imaging

PURPOSE To demonstrate the feasibility of low-dose photon-counting tomosynthesis in combination with a contrast agent (contrast material-enhanced tomographic mammography) for the differentiation of breast cancer. MATERIALS AND METHODS All studies were approved by the institutional review board, and all patients provided written informed consent. A phantom model with wells of iodinated contrast material (3 mg of iodine per milliliter) 1, 2, 5, 10, and 15 mm in diameter was assessed. Nine patients with malignant lesions and one with a high-risk lesion (atypical papilloma) were included (all women; mean age, 60.7 years). A multislit photon-counting tomosynthesis system was utilized (spectral imaging) to produce both low- and high-energy tomographic data (below and above the k edge of iodine, respectively) in a single scan, which allowed for dual-energy visualization of iodine. Images were obtained prior to contrast material administration and 120 and 480 seconds after contrast material administration. Four readers independently assessed the images along with conventional mammograms, ultrasonographic images, and magnetic resonance images. Glandular dose was estimated. RESULTS Contrast agent was visible in the phantom model with simulated spherical tumor diameters as small as 5 mm. The average glandular dose was measured as 0.42 mGy per complete spectral imaging tomosynthesis scan of one breast. Because there were three time points (prior to contrast medium administration and 120 and 480 seconds after contrast medium administration), this resulted in a total dose of 1.26 mGy for the whole procedure in the breast with the abnormality. Seven of 10 cases were categorized as Breast Imaging Reporting and Data System score of 4 or higher by all four readers when reviewing spectral images in combination with mammograms. One lesion near the chest wall was not captured on the spectral image because of a positioning problem. CONCLUSION The use of contrast-enhanced tomographic mammography has been demonstrated successfully in patients with promising diagnostic benefit. Further studies are necessary to fully assess diagnostic sensitivity and specificity.

Anterior dual rod instrumentation in idiopathic thoracic scoliosis: a computed tomography analysis of screw placement relative to the aorta and the spinal canal.

Study Design. Axial computed tomography scans (CT) in 20 consecutive patients with idiopathic right thoracic scoliosis and anterior correction and fusion with a dual rod dual screw system. Objectives. CT evaluation of screw position in anterior dual rod instrumentation relative to the aorta and the spinal canal. Summary of Background Data. In anterior scoliosis surgery, bicortical screw purchase is used to increase pullout strength. However, impingement of the aorta due to excessive contralateral screw penetration has been reported, especially after endoscopic instrumentation. Data on the accuracy of dual screw instrumentation in thoracic scoliosis are missing. Methods. All 20 patients underwent an identical anterior surgical technique with double thoracotomy approach and dual rod instrumentation of the primary curve. Postoperative sequential CT scans were analyzed with respect to following parameters: vertebral body width and depth, diameter of the aorta, distance from the aorta to the closest point of the vertebral body cortex, distance between the tip of the screws and the aorta, distance between the screw and the spinal canal, and the amount of contralateral screw penetration. A total amount of 226 screws were evaluated. Results. All screws were placed correctly without any critical proximity to the aorta or spinal canal. A total of 198 of 226 screws (88%) had a bicortical purchase. Thirteen screw tips (5.8%) were within 1 to 3 mm proximity to the aorta. All other screws were more than 3 mm distant from the aorta. The closest proximity of the screw tips to the thoracic aorta was found at the upper end vertebrae (T5, T6, or T7). There were no screws perforating the spinal canal. Conclusion. Anterior instrumentation and correction of thoracic scoliosis with a dual rod dual screw system enable a correct and safe screw placement using a standard open approach. Excessive bicortical screw perforation should be avoided in order not to endanger the thoracic aorta.

Coronary artery aneurysm and type-A aortic dissection demonstrated by retrospectively ECG-gated multislice spiral CT

The case of a 40-year-old male patient with a coronary aneurysm of the proximal left descending artery (LAD) combined with circumferential type-A dissection of the ascending aorta is reported. Computed tomography angiography of the coronary arteries was performed using multislice spiral computed tomography (MSCT) with retrospective ECG gating. Anatomical relations of the LAD aneurysm as well as the origin of the left coronary artery from the false lumen of the dissection were well depicted for planning of the surgical intervention using this new noninvasive imaging modality.