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Purpose: To evaluate the inter-rater agreement of cortical lesion detection using 7 Tesla (T) FLASH-T2 and 3T DIR sequences.Materials and Methods: Twenty-six patients with multiple sclerosis were scanned on a human 7T (Siemens) and 3T MRI (TIM Trio, Siemens) to acquire 3T DIR/MEMPR and 7T FLASH-T2 sequences. Four independent reviewers scored and categorized cortical lesions in the bilateral precentral gyri (motor strips) as leukocortical, intracortical, or subpial. Inter-rater agreement was assessed according to lesion category using the kappa statistic. The sensitivity of recent MAGNIMS consensus guidelines for cortical lesion detection using 3T DIR was assessed with 7T FLASH-T2 as the reference gold standard.Results: Inter-rater agreement at 7T was excellent compared with 3T (k = 0.97 versus 0.12). FLASH-T2 at 7T detected subpial lesions while 3T DIR did not. The predicted sensitivity of 3T DIR sequence for cortical lesions in vivo is modest (range of 13.6 to 18.3%).Conclusion: The 7T FLASH-T2 detects more cortical-particularly subpial-lesions compared with 3T DIR. In the absence of DIR/postmortem data, 7T FLASH-T2 is a suitable gold-standard instrument and should be incorporated into future consensus guidelines. [ABSTRACT FROM AUTHOR]

Our purpose was to investigate the potential of dynamic susceptibility contrast-enhanced MRI in assessing regional haemodynamics in patients with cerebrovascular disease. T2*-weighted FLASH sequences were performed on a control group of 10 healthy subjects, 13 patients with unilateral stenosis or occlusion of the internal carotid artery and 6 patients with acute onset of neurological symptoms, the observed signal intensities being converted into concentration-time curves. A gamma-variate function was fitted to the measured concentration-time curves to eliminate effects of tracer recirculation. In each patient the two cerebral hemispheres were compared and the difference between the mean transit times and the percental change of the regional cerebral blood volume, calculated for each side. Patients with haemodynamically significant unilateral carotid obstruction can be divided into two subgroups: those with good and those with poor collateral supply. Patients with good collateral supply had a slight but not statistically significant increase in mean transit time and cerebral blood volume on the diseased side, whereas those with poor collaterals had a significant increase compared with the control group. In patients with acute onset of neurological symptoms perfusion maps clearly demonstrated the disturbed perfusion at a time when T2-weighted images were still normal. Perfusion imaging is a reliable and noninvasive method of assessing changes in cerebral perfusion in patients with unilateral carotid stenosis. This MR technique permits monitoring of haemodynamic changes during therapy and thus may become an alternative to SPECT and PET scanning. In patients with acute occlusion of a cerebral artery, perfusion imaging reveals the entire perfusion deficit before conventional MRI and thus allows early intervention. [ABSTRACT FROM AUTHOR]

In the view of the German government, the One Health approach is a pioneering compass for inter- and transdisciplinary thinking, networking, and action. To protect the health of humans, animals, plants, and ecosystems, it should always receive attention at all its interfaces and activities. The One Health approach has gained political importance in recent years and is being taken into account in several strategies.This article reports on the current strategies using a One Health approach. These include the German Antibiotic Resistance Strategy, the German Strategy for Adaptation to Climate Change, the global initiative Nature for Health, and the international pandemic agreement, which is currently being drafted and in which prevention also plays an important role. The issues of biodiversity loss and climate protection must be placed in a common context that takes into account the interdependencies of the health status of humans, animals, plants, and ecosystems. By involving relevant disciplines at different levels as a matter of course, we can succeed in making a joint contribution to sustainable development, as required by the United Nations' Agenda 2030. This perspective guides Germany's global engagement in global health policy toward greater stability, freedom, diversity, solidarity, and respect for human rights. Thus, a holistic approach such as One Health can contribute to achieving sustainability and strengthening democratic principles., (© 2023. The Author(s).)

Background: MR image intensity nonuniformity is often observed at 7T. Reference scans from the body coil used for uniformity correction at lower field strengths are typically not available at 7T., Purpose: To evaluate the efficacy of a novel algorithm, Uniform Combined Reconstruction (UNICORN), to correct receive coil-induced nonuniformity in musculoskeletal 7T MRI without the use of a reference scan., Study Type: Retrospective image analysis study., Subjects: MRI data of 20 subjects was retrospectively processed offline. Field Strength/Sequence: Knees of 20 subjects were imaged at 7T with a single-channel transmit, 28-channel phased-array receive knee coil. A turbo-spin-echo sequence was used to acquire 33 series of images., Assessment: Three fellowship-trained musculoskeletal radiologists with cumulative experience of 42 years reviewed the images. The uniformity, contrast, signal-to-noise ratio (SNR), and overall image quality were evaluated for images with no postprocessing, images processed with N4 bias field correction algorithm, and the UNICORN algorithm., Statistical Tests: Intraclass correlation coefficient (ICC) was used for measuring the interrater reliability. ICC and 95% confidence intervals (CIs) were calculated using the R statistical package employing a two-way mixed-effects model based on a mean rating (k = 3) for absolute agreement. The Wilcoxon signed-rank test with continuity correction was used for analyzing the overall image quality scores., Results: UNICORN was preferred among the three methods evaluated for uniformity in 97.9% of the pooled ratings, with excellent interrater agreement (ICC of 0.98, CI 0.97-0.99). UNICORN was also rated better than N4 for contrast and equivalent to N4 in SNR with ICCs of 0.80 (CI 0.72-0.86) and 0.67 (CI 0.54-0.77), respectively. The overall image quality scores for UNICORN were significantly higher than N4 (P < 6 × 10 -13 ), with good to excellent interrater agreement (ICC 0.90, CI 0.86-0.93)., Data Conclusion: Without the use of a reference scan, UNICORN provides better image uniformity, contrast, and overall image quality at 7T compared with the N4 bias field-correction algorithm., Level of Evidence: 4 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:1534-1544., (© 2019 International Society for Magnetic Resonance in Medicine.)