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Sustained forms of atrial fibrillation (AF) may be associated with a higher risk of adverse outcomes, but few if any long-term studies took into account changes of AF type and co-morbidities over time. We prospectively followed 3843 AF patients and collected information on AF type and co-morbidities during yearly follow-ups. The primary outcome was a composite of stroke or systemic embolism (SE). Secondary outcomes included myocardial infarction, hospitalization for congestive heart failure (CHF), bleeding and all-cause mortality. Multivariable adjusted Cox proportional hazards models with time-varying covariates were used to compare hazard ratios (HR) according to AF type. At baseline 1895 (49%), 1046 (27%) and 902 (24%) patients had paroxysmal, persistent and permanent AF and 3234 (84%) were anticoagulated. After a median (IQR) follow-up of 3.0 (1.9; 4.2) years, the incidence of stroke/SE was 1.0 per 100 patient-years. The incidence of myocardial infarction, CHF, bleeding and all-cause mortality was 0.7, 3.0, 2.9 and 2.7 per 100 patient-years, respectively. The multivariable adjusted (a) HRs (95% confidence interval) for stroke/SE were 1.13 (0.69; 1.85) and 1.27 (0.83; 1.95) for time-updated persistent and permanent AF, respectively. The corresponding aHRs were 1.23 (0.89, 1.69) and 1.45 (1.12; 1.87) for all-cause mortality, 1.34 (1.00; 1.80) and 1.30 (1.01; 1.67) for CHF, 0.91 (0.48; 1.72) and 0.95 (0.56; 1.59) for myocardial infarction, and 0.89 (0.70; 1.14) and 1.00 (0.81; 1.24) for bleeding. In this large prospective cohort of AF patients, time-updated AF type was not associated with incident stroke/SE.

Differentiation between posttherapy radiation necrosis and recurrent tumor in humans with brain tumor is still a difficult diagnostic task. The new PET tracers 18F-fluoro-ethyl-l-tyrosine (FET) and 18F-fluorocholine (N,N-dimethyl-N-18F-fluoromethyl-2-hydroxyethylammonium [FCH]) have shown promise for improving diagnostic accuracy. This study assessed uptake of these tracers in experimental radiation injury. Methods: In a first model, circumscribed lesions were induced in the cortex of 35 rats using proton irradiation of 150 or 250 Gy. After radiation injury developed, uptake of 18F-FET, 18F-FCH, and 18F-FDG was measured using autoradiography and correlated with histology and disruption of the blood-brain barrier as determined with Evans blue. In a second model, uptake of the tracers was assessed in acute cryolesions, which are characterized by the absence of inflammatory cells. Results: Mean 18F-FET, 18F-FCH, and 18F-FDG standardized uptake values in the most active part of the radiation lesion and the contralateral normal cortex (in parentheses) were 2.27 ± 0.46 (1.42 ± 0.23), 2.52 ± 0.42 (0.61 ± 0.12), and 6.21 ± 1.19 (4.35 ± 0.47). The degree of uptake of 18F-FCH and 18F-FDG correlated with the density of macrophages. In cryolesions, 18F-FET uptake was similar to that in radiation lesions, and 18F-FCH uptake was significantly reduced. Conclusion: Comparison of tracer accumulation in cryolesions and radiation injuries demonstrates that 18F-FET uptake is most likely due to a disruption of the blood-brain barrier alone, whereas 18F-FCH is additionally trapped by macrophages. Uptake of both tracers in the radiation injuries is generally lower than the published uptake in tumors, suggesting that 18F-FET and 18F-FCH are promising tracers for separating radiation necrosis from tumor recurrence. However, the comparability of our data with the literature is limited by factors such as different species and acquisition protocols and modalities. Thus, more studies are needed

OBJECTIVE To investigate the performance of MR-defecography (MRD) in lateral body position as an alternative to supine position. METHODS 22 consecutive patients (16 females; mean age 51 ± 19.4) with obstructed defecation and 20 healthy volunteers (11 females; mean age 33.4 ± 11.5) underwent MRD in a closed-configuration 3T-MRI in supine and lateral position. MRD included T weighted images at rest and during defecation after filling the rectum with 250 ml water-based gel. Measurements were performed in reference to the pubococcygeal line and grade of evacuation was assessed. Image quality (IQ) was rated on a 5-point-scale (5 = excellent). RESULTS In patients grades of middle and posterior compartment descent were similar in both body positions (p > 0.05). Grades of anterior compartment descent were significantly higher in lateral position (21/22 vs 17/22 patients with normal or small descent, p < 0.034). In volunteers grades of descent were similar for all compartments in supine and lateral position (p > 0.05). When attempting to defecate in supine position 6/22 (27%) patients showed no evacuation, while in lateral position only 3/22 (14%) were not able to evacuate. IQ in patients was equal at rest (4.4 ± 0.5 and 4.7 ± 0.6, p > 0.05) and slightly better in supine compared to the lateral position during defecation (4.5 ± 0.4 vs 3.9 ± 0.9, p < 0.017). IQ in volunteers was equal in supine and lateral position (p > 0.05). CONCLUSION In lateral position, more patients were able to evacuate with similar grades of pelvic floor descent compared to supine position. MRD in lateral position may be a valuable alternative for patients unable to defecate in supine position. Advances in knowledge: In lateral position, more patients were able to evacuate during MRD. MRD in lateral position may be an alternative for patients unable to defecate in supine position.

Objective: To prospectively evaluate the diagnostic accuracy of whole-body T2-weighted (wbT2), whole-body diffusion-weighted imaging (wbDWI) and wbT2/wbDWI image fusion for malignant tumour detection compared with PET/CT. Methods: Sixty-eight patients (44 men; 60 ± 14years) underwent PET/CT for staging of malignancy and were consecutively examined by 1.5-Tesla MRI including wbT2 and wbDWI. Two radiologists independently assessed wbDWI, wbT2, wbT2 + wbDWI (side-by-side) and wbT2 + wbDWI + wbT2/wbDWI image fusion for the presence of malignancy. PET/CT served as a reference standard. Results: PET/CT revealed 374 malignant lesions in 48/64 (75%) patients. Detection rates and positive predictive value (PPV) of wbT2 and wbDWI alone were 64% and 84%, and 57% and 93%, respectively. Detection rates and PPV of wbT2 and wbDWI for side-by-side analysis without and with fused images were 72% and 89%, and 74% and 91%, respectively. The detection rate was significantly higher with side-by-side analysis and fused image analysis compared with wbT2 and wbDWI alone (p = .0159; p < .0001). There was no significant difference between fused image interpretation and side-by-side analysis. Conclusions: WbDWI allows detection of malignant lesions with a similar detection rate to wbT2. Side-by-side analysis of wbT2 and wbDWI significantly improves the overall detection rate and fused image data provides no added value

Magnetic resonance imaging (MRI) is an excellent tool to understand the complex anatomy of the pelvic floor and to assess pelvic floor disorders. MRI enables static and dynamic imaging of the pelvic floor. Using static T2-weighted sequences the morphology of the pelvic floor can be visualized in great detail. A rapid half-Fourier T2-weighted, balanced steady state free precession, or gradient-recalled echo sequence are used to obtain sagittal images while the patient is at rest, during pelvic squeeze, during pelvic strain and to document the evacuation process. On these images the radiologist identifies the pubococcygeal line (PCL) (which represents the level of the pelvic floor). In normal findings, the base of the anterior and the middle compartment are above the PCL at rest, and the pelvic floor elevates during contraction. During straining the pelvic floor muscles should relax and the pelvic floor descends normally less than 3cm below the PCL. Pelvic floor MRI based on the static and dynamic MRI sequences allows for the detection and characterization of a vast array of morphologic and functional pelvic floor disorders. In this review, we focus on technical aspects of static and dynamic pelvic floor MRI

Background: The purpose of this study was to assess the accuracy of double-contrast magnetic resonance (MR) imaging for the treatment response evaluation of hepatocellular carcinoma (HCC) in cirrhotic liver after transarterial chemoembolization (TACE). Methods: Twenty-two patients with 30 HCC nodules treated by TACE underwent double-contrast MR imaging 1month after treatment. MR images were obtained before and after the sequential administration of superparamagnetic iron oxide (SPIO) and gadopentetate dimeglumine contrast agent within the same imaging session. Two observers retrospectively assessed all treated nodules for evidence of residual viable tumor after TACE. The diagnostic performance of gadolinium-enhanced, SPIO-enhanced, and double-contrast enhanced images was calculated. Histopathological and angiographical findings served as standard of reference. Receiver operating characteristic curves and areas under the curves (A z) were calculated. Results: Double-contrast technique (A z=0.95) was significantly (p=0.036) more accurate than SPIO-enhanced technique (A z=0.92) and gadolinium-enhanced technique (p=0.005) (A z=0.81) in viable tumor detection after TACE. Double-contrast technique was significantly more sensitive (92%) than SPIO-enhanced technique (80%) and gadolinium-enhanced technique (68%). Kappa values for interobserver agreement ranged from 0.67 to 0.87 and were significantly different from zero (all p<0.001). Conclusions: Compared to gadolinium-enhanced and SPIO-enhanced techniques, double-contrast technique significantly improves the detection of viable tumor in HCC after TACE

The purpose of this study was to assess prospectively the potential of low-dose intranasal midazolam compared to oral midazolam in claustrophobic patients undergoing routine body magnetic resonance imaging (MRI). Seventy-two adult claustrophobic patients referred for body MRI were randomly assigned to one of two treatment groups (TG1 and TG2). The 36 patients of TG1 received 7.5mg midazolam orally 15min before MRI, whereas the 36 patients of TG2 received one (or, if necessary, two) pumps of a midazolam nasal spray into each nostril immediately prior to MRI (in total, 1 or 2mg). Patients' tolerance, anxiety and sedation were assessed using a questionnaire and a visual analogue scale immediately before and after MRI. Image quality was evaluated using a five-point-scale. In TG1, 18/36 MRI examinations (50%) had to be cancelled, the reduction of anxiety was insufficient in 12/18 remaining patients (67%). In TG2, 35/36 MRI examinations (97%) were completed successfully, without relevant adverse effects. MRI image quality was rated higher among patients of TG2 compared to TG1 (p<0.001). Low-dose intranasal midazolam is an effective and patient-friendly solution to overcome anxiety in claustrophobic patients in a broad spectrum of body MRI. Its anxiolytic effect is superior to that of the orally administrated form

Magnetic resonance (MR) imaging has become an important diagnostic tool in evaluation of the musculoskeletal system. While most examinations are currently performed at magnetic field strengths of 1.5T or lower, whole-body MR systems operating at 3.0T have recently become available for clinical use. The higher field strengths promise various benefits, including increased signal-to-noise ratios, enhanced T2* contrast, increased chemical shift resolution, and most likely a better diagnostic performance in various applications. However, the changed T1, T2, and T2* relaxation times, the increased resonance-frequency differences caused by susceptibility and chemical-shift differences, and the increased absorption of radiofrequency (RF) energy by the tissues pose new challenges and/or offer new opportunities for imaging at 3.0T compared to 1.5T. Some of these issues have been successfully addressed only in the very recent past. This review discusses technical aspects of 3.0T imaging as far as they have an impact on clinical routine. An overview of the current data is presented, with a focus on areas where 3.0T promises equivalent or improved performance compared 1.5T or lower field strengths

Objectives: To assess the diagnostic accuracy of 64-multidetector CT (MDCT) for restaging of patients with oesophageal cancer undergoing neoadjuvant therapy. Methods: Results of pathological staging were correlated with those from 64-MDCT before and after neoadjuvant treatment in 35 patients using the American Joint Committee on Cancer/TNM classification (7th edition). CT response was determined using the Response Evaluation Criteria in Solid Tumours (RECIST) method, modified for one-dimensional tumour diameter measurement. Results: 64-MDCT predicted T stage correctly in 34% (12/35), overstaged in 49% (17/35) and understaged in 17% (6/35). Sensitivity/specificity values were as follows: T0, 20%/92%; T1-T2, 31%/59%; T3, 60%/64%; T4, 100%/4%. Negative predictive values for T3/T4 were 80%/100%. MDCT accurately predicted complete histopathological response in 20% (accuracy 74%) and overstaged in 80%. Tumour regression grade was predicted correctly in only 8% (2/25) and underestimated in 68% (17/25). Accurate N stage was noted in 69% (24/35). Conclusion: Although MDCT tends to be able to exclude advanced tumour stages (T3, T4) with a higher likelihood, the diagnostic accuracy of high resolution MDCT for restaging oesophageal cancer and assessing the response to neoadjuvant therapy has not improved in comparison to older-generation CT. Therefore, the future assessment of oesophageal tumour response should focus on combined morphologic and metabolic imaging. Key Points : • Multidetector CT (MDCT) has been beneficial for the evaluation of many tumours. • However diagnostic accuracy for restaging oesophageal cancer has not improved with MDCT. • MDCT tends to be able to exclude advanced tumour stages (T3/T4). • MDCT has a low accuracy for determining lymph node metastasis. • Oesophageal tumour response should be assessed by combined morphological and metabolic imaging

Summary:: Assessing the vascular status and anatomy of the lower extremity is of crucial importance when planning the coverage of a tissue defect with a free flap. The standard techniques comprise the clinical examination, Doppler ultrasound and Doppler sonography for healthy patients without suspected direct trauma to the vascular system, and conventional digital subtraction angiography (DSA), respectively, in case of traumatized vessels or patients with peripheral arterial obstructive disease. Materials:: We have conducted a prospective study for the comparison of the magnetic resonance angiography (MRA) to the conventional DSA. Fourteen patients were examined presurgically by means of both a conventional DSA and an MRA before undergoing planned microvascular coverage of tissue defects of the lower extremity. The surgeon, based on a questionnaire, assessed and compared both examination results according to their information content. Furthermore, the presurgically planned level and localization of the vascular anastomoses and the intraoperative findings were compared postoperatively. Results:: The MRA examination yielded sufficient information on the vascular anatomy to enable the surgeon to carry out a detailed presurgical planning. Additionally, the use of MRA showed clear advantages with regard to both patient and user comfort. Conclusion:: Taking into account the advantages for the assessment of vessels using MRA, in particular when considering the impact of the frequently varying vascular anatomy of the lower leg on reconstructive surgery, as well as the significantly lower morbidity rate of the examination itself, then the MRA must be regarded as a safe alternative to the DSA

To investigate the role of MR imaging (MRI) in the evaluation of peripheral nerve lesions of the upper extremities and to assess its impact on the patient management. Fifty-one patients with clinical evidence of radial, median, and/or ulnar nerve lesions and unclear or ambiguous clinical findings had MRI of the upper extremity at 1.5T. MR images and clinical data were reviewed by two blinded radiologists and a group of three clinical experts, respectively, with regard to radial, median, and/or ulnar nerve, as well as muscle abnormalities. MRI and clinical findings were correlated using Spearman's (p) rank correlation test. The impact of MRI on patient management was assessed by the group of experts and ranked as "major,” "moderate,” or "no” impact. The correlation of MRI and clinical findings was moderate for the assessment of the median/radial nerve and muscles (p = 0.51/0.51/0.63, respectively) and weak for the ulnar nerve (p = 0.40). The impact of MRI on patient management was assessed as "major” in 24/51 (47%), "moderate” in 19/51 (37%), and "no” in 8/51 (16%) patients. MRI in patients with upper extremity peripheral neuropathies and unclear or ambiguous clinical findings substantially influences the patient management