Purpose: To characterize the ( 2 H) deuterium MR signal measured from human brain at 7T in participants loading with D 2 O to ∼1.5% enrichment over a six-week period. Methods: 2 H spectroscopy and imaging measurements were used to track the time-course of 2 H enrichment within the brain during the initial eight-hour loading period in two participants. Multi-echo gradient echo (MEGE) images were acquired at a range of TR values from four participants during the steady-state loading period and used for mapping 2 H T 1 and T 2 * relaxation times.Co-registration to higher resolution 1 H images allowed T 1 and T 2 * relaxation times of deuterium in HDO in cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) to be estimated.Results: 2 H concentrations measured during the eight-hour loading were consistent with values estimated from cumulative D 2 O dose and body mass. Signal changes measured from three different regions of the brain during loading showed similar time-courses. After summing over echoes, gradient echo brain images acquired in 7.5 minutes with a voxel volume of 0.36 ml showed an SNR of ∼16 in subjects loaded to 1.5%. T 1 -values for deuterium in HDO were significantly shorter than corresponding values for 1 H in H 2 O, while T 2 * values were similar. 2 H relaxation times in CSF were significantly longer than in GM or WM. Conclusion:Deuterium MR Measurements at 7T were used to track the increase in concentration of 2 H in brain during heavy water loading. 2 H T 1 and T 2 * relaxation times from water in GM, WM, and CSF are reported. heavy water, human brain, MEGE, relaxation timesThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Twelve patients underwent serial cardiac, cerebral and renal multiparametric 3T MRI scans before, during and after haemodialysis. During dialysis, there was a significant decline in cardiac and stroke index and myocardial strain, with increased diastolic dysfunction. This was accompanied by a reduction in blood flow to both the heart and brain. White matter T1 increased during dialysis suggesting fluid shifts increasing water content resulting in local oedema. Total kidney volume, renal cortex T1 and T2* all reduced during dialysis likely reflecting reduced renal blood volume and change in renal tissue water. These results highlight the acute multi-organ effects of dialysis.

Deuterium magnetic resonance imaging and spectroscopy at 7T has been used to follow the deuterium concentration in the brain over an ~eight-hour period while subjects orally-loaded with D2O to 100x natural abundance. Changes in deuterium concentration of ~ 0.1% can be readily monitored in 2H spectra acquired in 1 minute and images acquired in 7.5 minutes. The change in deuterium concentration estimated from 2H spectra is in agreement with the value calculated from cumulative D2O dose and body mass and the signal changes measured from ROIs in the brain have similar time-courses, with relative signal strengths dictated by T2*-weighting.

Deuterium magnetic resonance measurements are of growing interest in the field of metabolic imaging. Four subjects were loaded with D2O to ~1.5% enrichment over a 6-week period for a parallel study of immune cell proteomics. We report T1 and T2* relaxation times of deuterium in HDO measured from cerebral spinal fluid (CSF), white matter (WM) and grey matter (GM) in vivo, using a 7T Philips Achieva scanner with a dual-tuned 2H/1H birdcage coil. 2H T1 values are significantly shorter than corresponding values for 1H in H2O, due to the quadrupolar 2H relaxation, whilst T2* values are comparable to 1H values.

Double-quantum filtered (DQF) deuterium spectra were obtained on a 3T scanner from lower leg and forearm muscles of volunteers whose deuterium abundance was increased by approximately 100 times through ingestion of deuterium oxide. Quadrupolar splitting frequencies of approximately 20 – 40 Hz were measured throughout the various muscle groups of the lower leg, with some regions showing little or no splitting. Although the DQF sequence considerably reduces the signal intensity, it has the advantage that it removes any isotropic signal component and therefore reveals an anisotropic component that might have been obscured.