Hypertension is linked to disturbed total-body sodium (Na ⁺ ) regulation; however, measuring Na ⁺ disposition in the body is difficult. We implemented ²³ Na magnetic resonance spectroscopy ( ²³ Na-MR) and imaging technique ( ²³ Na-MRI) at 9.4T for animals and 3T for humans to quantify Na ⁺ content in skeletal muscle and skin. We compared ²³ Na-MRI data with actual tissue Na ⁺ content measured by chemical analysis in animal and human tissue. We then quantified tissue Na ⁺ content in normal humans and in patients with primary aldosteronism. We found a 29% increase in muscle Na ⁺ content in patients with aldosteronism compared with normal women and men. This tissue Na ⁺ was mobilized after successful treatment without accompanying weight loss. We suggest that, after further refinements, this tool could facilitate understanding the relationships between Na ⁺ accumulation and hypertension. Furthermore, with additional technical advances, a future clinical use may be possible.

Myocardial T1 and T2 mapping using cardiovascular magnetic resonance (CMR) are promising to improve tissue characterization and early disease detection. This study aimed at analyzing the feasibility of T1 and T2 mapping at 3 T and providing reference values.

Objective: To investigate distinct white matter and cortical gray matter pathology in neuromyelitis optica spectrum disorders (NMOSDs) and multiple sclerosis (MS) at 7-T MRI in a cross-sectional study. Methods: We included 10 patients with NMOSDs and 18 patients with MS in our 7-T MRI study. The imaging protocol comprised T2*-weighted fast low angle shot and turbo inversion recovery magnitude sequences. White matter and cortical gray matter lesions were assessed with special regard to their (perivascular) localization as well as the expression of a hypointense rim. Results: In total, we detected 140 white matter lesions in 7 of 10 patients with NMOSDs. In contrast to MS plaques, which were nearly exclusively centered by a small vein (92%) and showed a characteristic hypointense rim (23%), white matter changes in patients with NMOSDs were nonspecific in appearance and were only infrequently neighbored by a blood vessel (49 lesions [35%], p = 0.003). Hypointense rims were very rarely detectable (3 lesions [2%], p < 0.001). Cortical pathology was absent in NMOSDs. In our MS cohort, we detected 36 leukocortical, 8 intracortical, and 8 subpial cortical lesions in 7 of 18 patients. Conclusion: The MRI features of white matter and the absence of cortical gray matter findings substantially differentiate NMOSDs from MS and can be used as a potential marker to distinguish these 2 entities. The fact that cortical pathology is common in MS but is not present in patients with NMOSDs may reflect the difference in the underlying pathogenesis.