Magnetic resonance imaging (MRI) is one of the most commonly performed procedures and the financial backbone of diagnostic imaging. Since the populations of industrial countries are continuously aging and average morbidity is therefore increasing, demand for diagnostic procedures is growing. Labor and operating costs, however, are rising while reimbursement for medical procedures is declining. This makes efficient exploitation of the available resources of pivotal importance in an increasingly competitive healthcare market. Expanding the number of examined patients per MR scanner will help to meet the growing clinical demand and reliably improve profitability [1]. For this reason, an efficient and productive workflow with short patient changeover and acquisition times is essential. MR protocols should be sufficiently short, without losing time for planning and setting up the examinations. At the same time, high image quality has to be maintained to ensure diagnostic relevance. Investing in new acceleration techniques and workflow solutions will help to achieve these goals and bring forward the break-even point. The recently introduced BioMatrix Technology and syngo MR XA software provide several methods to streamline the daily workflow of MR technologists. In order to shorten patient changeover times, automated selection and positioning of coils have been integrated, as has automation of image acquisition using Dot engines. In addition to established parallel imaging techniques such as GRAPPA and CAIPIRINHA, advanced acceleration methods have been integrated into the clinical protocols: Simultaneous Multi-slice (SMS) imaging employs complex RF pulses to simultaneously acquire several sections along the z-axis, allowing a significant reduction in the image acquisition time by shortening the required TR time with little SNR penalty [2], while Compressed Sensing (CS) rapidly accelerates MR imaging by reconstructing sparse data from a highly undersampled k-space [3]. DIE RADIOLOGIE, a large radiology network in the Munich area, recently installed a 1.5T MAGNETOM Sola scanner equipped with BioMatrix Technology and the newest acceleration techniques, as provided by the syngo MR XA20 software. Recent studies have shown that these methods can shorten individual sequences and entire examinations. However, we were interested to know whether the integrated technology is also effective in daily clinical routine and whether it could potentially increase the profitability of an MR scanner.

Die Bildgebung der Niere hat in den letzten Jahren enorme Fortschritte erzielt. Dieser Beitrag gibt einen Überblick über die zurzeit zur Verfügung stehenden radiologischen Techniken zur Bildgebung von Nierentumoren und diskutiert in Entwicklung befindliche Techniken.

Objective To test the hypothesis that apparent diffusion coefficient (ADC) in vertebral bone marrow of benign and malignant fractures is related to the volume of the interstitial space, determined with dynamic contrast-enhanced (DCE) magnetic resonance imaging.Methods Patients with acute benign (n = 24) and malignant (n = 19) vertebral body fractures were examined at 1.5 T. A diffusion-weighted single-shot turbo-spin-echo sequence (b = 100 to 600 s/mm(2)) and DCE turbo-FLASH sequence were evaluated. Regions of interest were manually selected for each fracture. Apparent diffusion coefficient was determined with a monoexponential decay model. The DCE magnetic resonance imaging concentration-time curves were analyzed using a 2-compartment tracer-kinetic model.Results Apparent diffusion coefficient showed a significant positive correlation with interstitial volume in the whole study population (Pearson r = 0.66, P < 0.001), as well as in the malignant (Pearson r = 0.64, P = 0.004) and benign (Pearson r = 0.52, P = 0.01) subgroup. A significant correlation between ADC and the permeability-surface area product could be observed when analyzing the whole study population (Spearman r(s) = 0.40, P = 0.008), but not when separately examining the subgroups. Plasma flow showed a significant correlation with ADC in benign fractures (Pearson r = 0.23, P = 0.03). Plasma volume did not show significant correlations with ADC.Conclusions The results support the hypothesis that the ADC of a lesion is inversely correlated to its cellularity. This explains previous observations that ADC is reduced in more malignant lesions.

Background: Follow-up care in breast cancer is still an issue of debate. Diagnostic methods are more sensitive, and more effective therapeutic options are now available. The risk of recurrence is not only influenced by tumour stage but also by the different molecular subtypes. This study was performed to evaluate the use of whole-body imaging combined with tumour marker monitoring for the early detection of asymptomatic metastatic breast cancer (MBC). Methods: This analysis was performed as part of a follow-up study evaluating 813 patients with a median follow-up of 63 months. After primary therapy, all patients underwent tumour marker monitoring for CEA, CA 15-3 and CA 125 at 6-week intervals within an intensified diagnostic aftercare algorithm. A reproducible previously defined increase was considered as a strong indicator of MBC. From 2007 to 2010, 44 patients with tumour marker increase underwent whole-body magnetic resonance imaging and/or an FDG-PET/CT scan. Histological clarification and/or imaging follow-up were done. Results: Metastases were detected in 65.9% (29/44) of patients, 13.6% (6/44) had secondary malignancies besides breast cancer and 20.5% (9/44) had no detectable malignancy. Limited disease was found in 24.1% (7/29) of patients. Median progression-free survival of MBC was 9.2 months and median overall survival was 41.1 months. The 3- and 5-year survival rates were 64.2% and 40.0%, respectively. Conclusions: A reproducible tumour marker increase followed by whole-body imaging is highly effective for early detection. By consequence, patients might benefit from earlier detection and improved therapeutic options with a prolonged survival.

OBJECTIVE The purpose of our study was to determine the optimum combination of b values for calculating the apparent diffusion coefficient (ADC) using a diffusion-weighted (DW) single-shot turbo spin-echo (TSE) sequence in the differentiation between acute benign and malignant vertebral body fractures. SUBJECTS AND METHODS Twenty-six patients with osteoporotic (mean age, 69 years; range, 31.5-86.2 years) and 20 patients with malignant vertebral fractures (mean age, 63.4 years; range, 24.7-86.4 years) were studied. T1-weighted, STIR, and T2-weighted sequences were acquired at 1.5 T. A DW single-shot TSE sequence at different b values (100, 250, 400, and 600 s/mm(2)) was applied. On the DW images for each evaluated fracture, an ROI was manually adapted to the area of hyperintense signal intensity on STIR-hypointense signal on T1-weighted images. For each ROI, nine different combinations of two, three, and four b values were used to calculate the ADC using a least-squares algorithm. The Student t test and Mann-Whitney U test were used to determine significant differences between benign and malignant fractures. An ROC analysis and the Youden index were used to determine cutoff values for assessment of the highest sensitivity and specificity for the different ADC values. The positive (PPV) and negative predictive values (NPV) were also determined. RESULTS All calculated ADCs (except the combination of b = 400 s/mm(2) and b = 600 s/mm(2)) showed statistically significant differences between benign and malignant vertebral body fractures, with benign fractures having higher ADCs than malignant ones. The use of higher b values resulted in lower ADCs than those calculated with low b values. The highest AUC (0.85) showed the ADCs calculated with b = 100 and 400 s/mm(2), and the second highest AUC (0.829) showed the ADCs calculated with b = 100, 250, and 400 s/mm(2). The Youden index with equal weight given to sensitivity and specificity suggests use of an ADC calculated with b = 100, 250, and 400 s/mm(2) (cutoff ADC, < 1.7 × 10(-3) mm(2)/s) to best diagnose malignancy (sensitivity, 85%; specificity, 84.6%; PPV, 81.0%; NPV, 88.0%). CONCLUSION ADCs calculated with a combination of low to intermediate b values (b = 100, 250, and 400 s/mm(2)) provide the best diagnostic performance of a DW single-shot TSE sequence to differentiate acute benign and malignant vertebral body fractures.

OBJECTIVEBeta-2-microglobulin is a serum maker of tumor burden in hematologic malignancies. We aimed to correlate serum β2-microglobulin levels in patients with multiple myeloma (MM) to tumor mass determined by whole-body MRI.MATERIALS AND METHODSWe retrospectively included patients with newly diagnosed, untreated MM who underwent whole-body MRI at our institution between 2003 and 2011. Patients with a glomerular filtration rate of less than 60 mL/min were excluded from analysis because β2-microglobulin levels are increased in renal failure. Thirty patients could be included. Whole-body MRI examinations (T1-weighted turbo spin-echo and STIR sequences) were assessed by two musculoskeletal radiologists in consensus for focal lesions and the presence of diffuse myeloma infiltration. The presence of diffuse infiltration was confirmed by histology as the reference standard. MM was staged according to the Durie and Salmon PLUS staging system.RESULTSAccording to whole-body MRI findings, MM was classified as Durie and Salmon PLUS stage I (low grade) in 13 patients, stage II (intermediate grade) in six patients, and stage III (high grade) in 11 patients. As we expected, most patients with stage I disease (12/13) had normal β2-microglobulin levels (≤ 3 mg/L). Higher β2-microglobulin values were associated with a higher stage of disease (p < 0.05). However, five of six patients with stage II MM and five of 11 patients with stage III MM showed normal β2-microglobulin levels. Thus, 10 of 17 patients (58.8%) with substantial infiltration in the bone marrow showed false-negative β2-microglobulin levels.CONCLUSIONSerum β2-microglobulin levels correlate with tumor stage in MM. However, it may be misleading as a marker of tumor load in a subset of patients with substantial myeloma infiltration in the bone marrow. Whole-body MRI may display the full tumor load and correctly show the extension of myeloma infiltrates.

OBJECTIVE The objective of our study was to evaluate quantitative dynamic contrast-enhanced MRI (DCE-MRI) based on tracer kinetic modeling of perfusion in the differentiation of benign from malignant vertebral fractures. SUBJECTS AND METHODS Patients with 26 osteoporotic vertebral fractures (18 women, eight men; mean age, 69 years) and patients with 20 malignant vertebral fractures (nine women, 11 men; mean age, 63.4 years) underwent dynamic contrast-enhanced MRI. T1-weighted, STIR, and T2-weighted sequences were acquired at 1.5 T. Dynamic contrast-enhanced image sets were acquired with a 2D saturation-recovery spoiled gradient-echo sequence. Regions of interest in parameter maps of mean transit time (MTT) and plasma flow in the fractured vertebral bodies were analyzed with a two-compartment tracer kinetic model. Plasma flow, plasma volume (PV), extraction flow, and interstitial volume were calculated. The forward volume transfer constant (K(trans)) and the extracellular volume (ECV) were derived. A two-tailed Fisher exact test, Mann-Whitney U test, and receiver operating characteristic analysis were performed. RESULTS Forty-four vertebral fractures in 44 patients could be evaluated. In spots of increased plasma flow, interstitial volume (p = 0.0003), ECV (p = 0.002), and extraction flow (p = 0.03) for osteoporotic and malignant vertebral fractures were significantly different. The mean interstitial volume was 28.62 mL/100 mL for osteoporotic fractures and 11.73 mL/100 mL for malignant fractures, and the area under the curve (AUC) was 0.819 for a cutoff of 11.72 mL/100 mL or less indicating malignancy (sensitivity, 63.2%; specificity, 96.0%). The mean ECV was 52.68 mL/100 mL for osteoporotic fractures and 36.71 mL/100 mL for malignant fractures, and the AUC was 0.802 for a cutoff of 35.83 mL/100 mL or less indicating malignancy (sensitivity, 63.2%; specificity, 92.0%). The mean extraction flow was 15.19 mL/100 mL/min for osteoporotic fractures and 23.67 mL/100 mL/min for malignant fractures, and the AUC was 0.693 for a cutoff of 6.52 mL/100 mL/min or less indicating malignancy (sensitivity, 57.9%; specificity, 92.0%). K(trans), plasma flow, and PV in the spots of increased plasma flow and all quantitative perfusion parameters in the regions of increased MTT did not show any significant differences between benign and malignant fractures. CONCLUSION In spots of high plasma flow, which can be determined with a deconvolution analysis, the quantitative perfusion parameters of interstitial volume, ECV, and extraction flow are significantly different between acute osteoporotic and malignant vertebral fractures and can aid in the distinction between the two entities.

The skeletal system is a frequent target of metastatic spread from various primary tumors such as carcinoma of the breast, lung and prostate cancer. Therefore, it is highly important to accurately assess skeletal metastases in order to facilitate adequate therapy and predict patients’ prognosis. However, only pronounced destruction of bone with loss of mineral content exceeding 50% is readily visible in radiographic examinations. Computed tomography (CT) is definitely more sensitive than radiography and it is the imaging modality of choice to evaluate the extent of destruction of trabecular and cortical bone and to assess stability and fracture risk. Magnetic resonance imaging (MRI), on the other hand, allows visualization of bone marrow structure, such as hematopoietic—and fat cell components. Moreover, tumor infiltration into the spinal canal and paravertebral soft tissues is clearly depicted. The combination of unenhanced T1-weighted-spin echo- and turbo-STIR-sequences has shown to be most useful for the detection of bone marrow abnormalities and is able to discriminate benign from malignant bone marrow changes. Compared with other imaging modalities like radiography, CT or bone scintigraphy, it is the most sensitive technique for the detection of bone marrow pathologies, even if trabecular bone is not destroyed. Recently, multi-channel whole-body MRI (WB-MRI) scanners have been introduced and allow for head-to-toe assessment of the whole skeletal system without compromises in image quality compared with dedicated examinations of limited anatomical areas. Accordingly, WB-MRI has become a useful and sensitive alternative to standard whole-body imaging procedures such as skeletal scintigraphy or whole-body CT.

PURPOSE To evaluate diagnostic performance of gallium 68-tetraazacyclododecane tetraacetic acid-octreotate ((68)Ga-DOTATATE) in detection of recurrent neuroendocrine tumors (NETs). MATERIALS AND METHODS Approval was waived by the local ethics committee for this retrospective study. Between 2007 and 2011, 63 patients (mean age, 58 years) were examined with (68)Ga-DOTATATE positron emission tomography (PET)/computed tomography (CT) after primary NET curative resection. Reasons for PET/CT were regular follow-up examinations (n = 30), increased plasma levels of tumor markers (n = 27), or clinical suspicion of recurrence (n = 6). Final diagnosis was determined with histopathologic verification (n = 25) or clinical follow-up (n = 38). PET/CT scans were evaluated in consensus by two readers without blinding to clinical information and independently by two readers with blinding. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. RESULTS Final diagnosis of NET recurrence was determined in 29 patients. In three other patients, tumors of nonneuroendocrine origin were diagnosed. (68)Ga-DOTATATE PET/CT helped identify NET recurrence in 26 of 29 patients (sensitivity, 90%) and exclude presence of recurrent NET in 28 of 34 patients (specificity, 82% ). PET/CT provided false-positive and false-negative results in six and three patients (PPV, 81% [26 of 32]; NPV, 90% [28 of 31]; accuracy, 86% [54 of 63]). In gastroenteropancreatic NET (n = 45), sensitivity was 94% (17 of 18); specificity was 89% (24 of 27); PPV was 85% (17 of 20); NPV was 96% (24 of 25); and accuracy was 91% (41 of 45). Two blinded readers achieved sensitivity of 79% (23 of 29) and 76% (22 of 29); specificity of 85% (29 of 34) and 94% (32 of 34) (κ = 0.80); and accuracy of 83% and 86%. CONCLUSION (68)Ga-DOTATATE PET/CT is accurate in detection of recurrent NET. Blinded PET/CT review markedly decreased sensitivity, underlining importance of considering clinical parameters in NET recurrence. Present results must be further validated to substantiate use of (68)Ga-DOTATATE PET/CT in routine follow-up after curative resection of NET.

Radioembolization of primary and secondary liver tumors has emerged as valuable treatment option. CT and especially MRI are very helpful in delineating the tumors and estimating the liver involvement and are still considered as standard in oncologic imaging. Diffusion-weighted MRI has shown promising results in very early treatment assessment in a recent study. However, traditional therapy monitoring using RECIST or WHO criteria may be hampered by the specific changes of tumors treated with radioembolization. Multi-modal imaging, especially in the case of whole-body imaging, may overcome these drawbacks and provide more precise prognostic stratification due to the additional metabolic information. Recent studies indicate an advantage of FDG PET/CT in therapy montoring of radioembolization, in particular in cholangiocellular charcinoma, breast cancer and colorectal cancer. Further on, whole-body MRI has shown to be useful in pre-therapeutic triage of patients and the diagnosis of extra-hepatic metastases.

419 Objectives There is no consensus about the optimal follow-up examinations after curative resection of neuroendocrine tumors (NET). Inconclusive results obtained from different imaging modalities often complicate patient management and cause discomfort to the patients. Therefore, we evaluated 68Ga-DOTATATE PET/CT for the detection of NET recurrence. Methods 70 patients (37 male, mean age 58 years) in the follow-up after curative resection of primary NET were examined with 68Ga-DOTATATE PET/CT. The primary tumor was located in the small bowel (n=56), colon (n=8), stomach (n=3) or thyroid (n=3). 27/70 patients had elevated levels of Chromogranin A or NSE at the time point of PET/CT. Final diagnosis was made by histopathological verification (n=21) or clinical follow-up of mean 104 weeks (n=49). Results In 31 patients (44%) presence of NET recurrence was verified by histopathology or follow-up examinations. Most frequently the metastases of the recurrent NET were located in the liver (n=14), lymph nodes (n=8), lung (n=4), bones (n=3), soft tissue (n=3) or presented as local recurrence (n=14). Three patients had tumors of non-neuroendocrine origin (each one non-Hodgkin lymphoma, signet-ring carcinoma and colorectal cancer). 68Ga-DOTATATE PET/CT identified NET recurrence in 28/31 patients, and excluded the presence of a recurrent NET in 33/39 patients, indicating sensitivity of 90% and specificity of 85%. The PET/CT gave a false positive result in six patients, and a false negative in another three patients, indicating positive and negative predictive values of 82% and 92%, and an accuracy of 87%. Conclusions In patients` follow-up after curative resection of a NET 68Ga-DOTATATE PET/CT is highly accurate, thus substantiating its use in clinical routine diagnostics

UNLABELLED:In patients with suspected but yet not localized neuroendocrine tumors (NETs), early diagnosis or reliable exclusion is crucial for optimal individual prognosis and therapy. Despite recourse to several imaging modalities, the definite diagnosis of NET can be challenging. Therefore, we tested (68)Ga-DOTATATE PET/CT as a tool for improved diagnosis in a cohort of patients with suspected, nonlocalized NET. METHODS:(68)Ga-DOTATATE PET/CT recordings were obtained in 104 consecutive patients meeting at least one of the following criteria: clinical suspicion of NET (n = 70), elevated blood levels of tumor markers (n = 49), and image-based suspicion of NET (n = 53). The presence of NET was validated by histopathology (n = 49) or clinical follow-up of 107 ± 59 wk (n = 55). RESULTS:In 36 of 104 patients (35%), NET was histologically verified, most frequently located in the small bowel (10/36), pancreas (8/36), lung (5/36), and stomach (2/36). Twelve patients had tumors of nonneuroendocrine origin, and 7 patients had benign tumors. (68)Ga-DOTATATE PET/CT identified NET in 29 of the 36 cases and excluded the presence of a NET in 61 of the 68 non-NET patients, indicating a sensitivity of 81% and specificity of 90%. The PET/CT gave a false-positive result in 7 patients and a false-negative in another 7 patients, indicating positive and negative predictive values of 81% and 90%, respectively, and an accuracy of 87%. Chromogranin A levels were significantly higher in both PET-positive patients (1,841 vs. 342 ng/mL; P < 0.05) and patients with verified NET (2,214 vs. 524 ng/mL; P < 0.05). CONCLUSION:In patients with suspected NETs due to clinical symptoms, elevated levels of tumor markers, or indeterminate tumors suggestive of NET, (68)Ga-DOTATATE PET/CT is highly accurate, thus supporting its use in clinical routine diagnostics.

Purpose: The purpose was to evaluate the potential of FDG-PET-CT and whole-body MRI (WB-MRI) as diagnostic triage methods for patients planned for radioembolisation of metastatic liver disease.Materials and methods: 135 patients with multifocal liver metastases were evaluated for potential palliative therapy with radioembolisation using 90-Yttrium microspheres. All patients were examined consecutively with FDG-PET-CT and WB-MRI for exclusion of relevant extra-hepatic tumor manifestations. All patients underwent 99mTc-albumine angiography followed by scintigraphy to exclude significant hepato-pulmonary shunting.Results: Out of the 135 patients included into the pre-therapeutic diagnostic algorithm, 56% were eligible and received radioembolisation, while 44% could not be treated. In 91% the exclusion criteria was diagnosis of significant extra-hepatic metastatic disease. In 85% exclusion diagnosis was made concordantly by both FDG-PET-CT and WB-MRI, in 9% diagnosis was provided by PET-CT, in 6% by WB-MRI alone. Patient-based sensitivity for detection of extra-hepatic disease was 94% for PET-CT and 91% for WB-MRI. False-positive diagnosis of extrahepatic disease leading to exclusion for radioembolisation therapy was made in 2% of patients, in one patient by PET-CT and in one patient by WB-MRI alone. Overall, specificity for inclusion of radioembolisation therapy by combining both modalities was 99%. In 9% of patients angiographic diagnosis made radioembolisation impossible, in 7% solely the angiographic findings were decisive.Conclusion: Both FDG-PET-CT and WB-MRI are efficient diagnostic triage methods for patients planned for radioembolisation of liver metastases. Overall, FDG-PET-CT shows a trend to higher diagnostic accuracy compared to WB-MRI and may be used as imaging method of choice as a standalone examination. In combination, both modalities exhibited high sensitivity for the diagnosis of extra-hepatic tumor manifestations and result in high specificity. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Breast cancer is the most frequent malignancy and most common cause of cancer-related death in women worldwide with approximately 500,000 deaths each year [1]. Approximately 10–20% of all patients diagnosed with breast cancer will develop tumor recurrence at some time within the course of their disease. Therefore, early diagnosis and accurate restaging of recurrent breast cancer is important to define appropriate therapeutic strategies or to identify patients with limited disease who potentially could benefit from curative treatment. The basic strategy in the follow-up of breast cancer to date consists of regular mammography and clinical examinations as well as symptomorientated multi-modal imaging strategies [2]. This procedure by large is based on assumptions from studies performed in the early 90’s, that an intensified after-care does not necessarily correlate with an increased survival benefit [3,4]. Unfortunately, this approach mainly comprises modalities with known poor sensitivity (e.g. chest radiographs), examinations with examinerdependent variation of sensitivity (e.g. abdominal ultrasound) or procedures with limited specificity, like bone scintigraphy [5, 6]. In the last 10 years numerous promising concepts have been developed for the therapy of metastasized breast cancer, including hormonal drugs and immune therapy, which indicate an improvement in patients’ progression-free survival [6–8]. New surgical and interventional techniques for the management of limited disease have demonstrated its effectiveness and reported promising survival rates [8,9]. Against this background, whole-body imaging modalities, such as fluorodeoxyglucose positron emission tomography (FDG-PET)-CT or whole body-MRI (WB-MRI) appear as new promising tools to detect tumor recurrence with high accuracy and to provide more effective therapeutic strategies to the patient. It has been reported that whole-body fluorodeoxyglucose (FDG)positron emission tomography (PET) is of clinical value in the search for breast cancer metastases, especially when suggested by the presence of clinical symptoms or by a progressive increase in biochemical markers [9,10]. The combination of metabolic data from PET with the detailed anatomical information of multi-slice computed tomography as dual-modality scanners has markedly increased lesion localization and diagnostic accuracy compared to both modalities as standalone applications [11,12]. Recently, combined PET-CT has been introduced as a whole-body imaging modality for screening of patients with suspicion of recurrent breast cancer, indicating an improved restaging accuracy and possible impact on therapy [13].

Staging/Follow-up beim kolorektalen Karzinom wird normalerweise mit multimodalen Bildgebungsverfahren durchgeführt. Diese können jedoch zeitintensiv sein und bergen die Gefahr einer untersucherabhängigen Befundvarianz. Alternativ bietet die Ganzkörper-MRT eine onkologische Bildgebung mit einem systemischen Ansatz.

OBJECTIVE. The objective of our study was to compare the diagnostic value of qualitative diffusion-weighted imaging (DWI), quantitative DWI, and chemical-shift imaging in a single prospective cohort of patients with acute osteoporotic and malignant vertebral fractures.SUBJECTS AND METHODS. The study group was composed of patients with 26 osteoporotic vertebral fractures (18 women, eight men; mean age, 69 years; age range, 31 years 6 months to 86 years 2 months) and 20 malignant vertebral fractures (nine women, 11 men; mean age, 63.4 years; age range, 24 years 8 months to 86 years 4 months). T1-weighted, STIR, and T2-weighted sequences were acquired at 1.5 T. A DW reverse fast imaging with steady-state free precession (PSIF) sequence at different delta values was evaluated qualitatively. A DW echo-planar imaging (EPI) sequence and a DW single-shot turbo spin-echo (TSE) sequence at different b values were evaluated qualitatively and quantitatively using the apparent diffusion coefficient. Opposed-phase sequences were used to assess signal intensity qualitatively. The signal loss between in-and opposed-phase images was determined quantitatively. Two-tailed Fisher exact test, Mann-Whitney test, and receiver operating characteristic analysis were performed. Sensitivities, specificities, and accuracies were determined.RESULTS. Qualitative DW-PSIF imaging (delta = 3 ms) showed the best performance for distinguishing between benign and malignant fractures (sensitivity, 100%; specificity, 88.5%; accuracy, 93.5%). Qualitative DW-EPI (b = 50 s/mm(2) [p = 1.00]; b = 250 s/mm(2) [p = 0.50]) and DW single-shot TSE imaging (b = 100 s/mm(2) [p = 1.00]; b = 250 s/mm(2) [p = 0.18]; b = 400 s/mm(2) [p = 0.18]; b = 600 s/mm(2) [p = 0.39]) did not indicate significant differences between benign and malignant fractures. DW-EPI using a b value of 500 s/mm(2) (p = 0.01) indicated significant differences between benign and malignant vertebral fractures. Quantitative DW-EPI (p = 0.09) and qualitative opposed-phase imaging (p = 0.06) did not exhibit significant differences, quantitative DW single-shot TSE imaging (p = 0.002) and quantitative chemical-shift imaging (p = 0.01) showed significant differences between benign and malignant fractures.CONCLUSION. The DW-PSIF sequence (delta = 3 ms) had the highest accuracy in differentiating benign from malignant vertebral fractures. Quantitative chemical-shift imaging and quantitative DW single-shot TSE imaging had a lower accuracy than DW-PSIF imaging because of a large overlap. Qualitative assessment of opposed-phase, DW-EPI, and DW single-shot TSE sequences and quantitative assessment of the DW-EPI sequence were not suitable for distinguishing between benign and malignant vertebral fractures.

To evaluate safety, efficacy, and symptom-control of radioembolization in patients with unresectable liver metastases from neuroendocrine tumors (NETLMs).

Staging and follow-up of colorectal cancer are usually performed with multimodal imaging strategies. These can be time-intensive and potentially lead to examiner-dependent bias. Alternatively, whole body magnetic resonance imaging (WB-MRI) provides oncologic imaging with a systemic approach. Ultrasound, multislice computed tomography (MSCT), dedicated MRI and positron emission tomography/CT (PET/CT). High-resolution WB-MRI with focused examination of various organs, such as the pelvis and abdomen, lungs, brain and skeletal system, using different sequence and contrast techniques. Detection of colorectal tumor recurrence with WB-MRI provides 83% accuracy (lymph node metastases 80%, organ metastases 86%). Potential cost reduction through decreased examination time and personnel costs. Whole body MRI is a radiation-free alternative to standard sequential algorithms of staging and follow-up of colorectal cancer.

Ziele: Ziel der Studie war, die Rolle der 18F-FDG-PET-CT zum Nachweis von Primärtumoren und Metastasen bei Patienten mit paraneoplastischen neurologischen Syndromen (PNS) im Vergleich zur kontrastverstärkten CT (KM-CT) zu evaluieren. Methode: PET-CT von 66 Patienten mit PNS (z.B. limbische Enzephalitis) wurden retrospektiv ausgewertet. Zunächst beurteilten 2 geblindete Reviewer die KM-CT-Komponente alleine; in einer 2. Sitzung 3 Monate später wurden die vollständigen PET-CT-Untersuchungen analysiert. Befunde wurden anhand einer 4-Punkt-Skala beurteilt (1: normal/gutartig; 2: unklar, weitere diagnostische Abklärung nötig; 3: maligne; 4: entzündlich). Die Ergebnisse wurden zu den klinischen Daten aus den Patientenakten korreliert. Ergebnis: 12 Befunde bei 10/66 (15,2%) Patienten wurden alle korrekt als maligne im PET-CT klassifiziert (2 Patienten mit jeweils 2 Primärtumoren). Die häufigsten Tumore waren Lungenkarzinome (n:3); Lymphknotenmetastasen von gynäkologischen Tumoren (n:3) und Tonsillenkarzinome (n:2). 3/12 (25%) der Malignome wurden im KM-CT nicht detektiert (Cervixkarzinom, Lymphknotenmetastase, Tonsillenkarzinom). Allerdings wurden bei 16/66 (24,2%) Patienten 21 Befunde als unklar klassifiziert. 57% dieser Befunde wurden nur durch die PET-Komponente diagnostiziert (z.B. fokale FDG-Aufnahme in Schilddrüse, Darm, Ovarien). In keinem dieser Fälle wurde im klinischen Verlauf ein Malignom gefunden. Schlussfolgerung: Mit der PET-CT wurden die ursächlichen Malignome in 15,2% der Patienten mit PNS korrekt detektiert. Die Hybridbildgebung war der alleinigen KM-CT überlegen. Auch wenn durch unklare PET-Befunde relativ häufig eine weitere diagnostische Abklärung verursacht wird, erhöht die PET-Komponente die diagnostische Genauigkeit insbesondere bei Kopf-Hals- und gynäkologischen Tumoren sowie Lymphknotenmetastasen.