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•We examined subregional metrics of thalamus and hippocampus in MS using 7T MRI.•Smaller bilateral anterior thalamic volume correlated with worse gait function.•Most thalamic nuclei correlated with visual and cognitive processing speed.•Volumes correlated with T1 relaxation time in a subset of thalamic nuclei.•Ultrahigh field MRI detects structural changes informative of MS outcomes.

MR imaging has been optimized for the evaluation of a multitude of disease processes affecting the kidneys. A wide variety of noncontrast methods are available for the evaluation of both kidney structure and function, which are especially useful in clinical scenarios that obviate the use of intravenous contrast. Contrast-enhanced methods remain important, especially for tumor evaluation, and are used increasingly for functional analysis of quantitative biometrics, such as glomerular filtration rate and kidney blood flow.

A single-shot fast spin-echo pulse sequence with variable refocusing flip angles and full-Fourier acquisition leads to a doubling of 3-T acquisition speed via reduced radiofrequency energy deposition and demonstrates significant improvements in perceived image quality and perceived diagnostic capability when evaluating structures in the pelvis.

Alzheimer's disease (AD) is the most common cause of dementia worldwide. Increasing evidence points to the thalamus as an important hub in the clinical symptomatology of the disease, with the ‘limbic thalamus’ been described as especially vulnerable. In this work, we examined thalamic atrophy in early-onset AD (EOAD) and late-onset AD (LOAD) compared to young and old healthy controls (YHC and OHC, respectively) using a recently developed cutting-edge thalamic nuclei segmentation method. A deep learning variant of Thalamus Optimized Multi Atlas Segmentation (THOMAS) was used to parcellate 11 thalamic nuclei per hemisphere from T1-weighted MRI in 88 biomarker-confirmed AD patients (49 EOAD and 39 LOAD) and 58 healthy controls (41 YHC and 17 OHC) with normal AD biomarkers. Nuclei volumes were compared among groups using MANCOVA. Further, Pearson's correlation coefficient was computed between thalamic nuclear volume and cortical—subcortical regions, CSF tau levels, and neuropsychological scores. The results showed widespread thalamic nuclei atrophy in EOAD and LOAD compared to their respective healthy control groups, with EOAD showing additional atrophy in the centromedian and ventral lateral posterior nuclei compared to YHC. In EOAD, increased thalamic nuclei atrophy was associated with posterior parietal atrophy and worse visuospatial abilities, while LOAD thalamic nuclei atrophy was preferentially associated with medial temporal atrophy and worse episodic memory and executive function. Our findings suggest that thalamic nuclei may be differentially affected in AD according to the age at symptoms onset, associated with specific cortical—subcortical regions, CSF total tau and cognition.

The aim of this study was to optimize the 3-dimensional (3D) fluid attenuated inversion recovery (FLAIR) pulse sequence for isotropic high-spatial-resolution imaging of white matter (WM) and cortical lesions at 7 T.

To improve the signal-to-noise ratio (SNR) of breath-held coronary magnetic resonance angiography (CMRA) without increasing the number or duration of breath holds. In this BACSPIN (Breathing AutoCorrection with SPiral INterleaves) technique, a single breath-held electrocardiogram (ECG)-gated multi-slice interleaved-spiral data set is acquired, followed by repeated imaging of the same slices during free breathing. Each spiral interleaf from the breath-held data set is used as a standard for comparison with corresponding acquisitions at the same interleaf angle during free breathing. The most closely matched acquisitions are incorporated into a multi-slice, multi-average data set with increasing SNR over time. In-plane translations of the coronary artery can be measured and compensated for each accepted acquisition before combination with the other acquisitions. CMRA was performed on six volunteers, with improved SNR and minimal motional blurring. In some cases, breath holding could be dispensed with completely and the average respiratory position used as a reference. BACSPIN provides a promising method for CMRA with improved SNR and limited breath-holding requirements. J. Magn. Reson. Imaging 2003;17:170–176. © 2003 Wiley-Liss, Inc.

This work describes a technique that combines multishot echo‐planar imaging (EPI) with steady‐state free precession (SSFP, also known as TrueFISP, FIESTA, and balanced FFE) for multislice, cine MR imaging of the heart. Unlike recently reported methods, the technique presented here (FIESTA‐ET) is high‐resolution and does not require offline reconstruction or postprocessing. It is therefore suitable for use on standard clinical scanners. FIESTA‐ET was compared with conventional FIESTA imaging in 10 volunteers and quantitative analyses of myocardial signal‐to‐noise ratios (SNR) and ventricular volumes were performed. While providing comparable image quality, FIESTA‐ET required half the acquisition time per slice of conventional FIESTA. Because multiple slices could be imaged in a single breathhold, the entire heart could be scanned in less than 2 min. Although the FIESTA‐ET images exhibited an unexpected increase (P< 0.0005) in myocardial SNR of 16% over FIESTA, the volumetric measurements showed excellent correlation. Magn Reson Med 48:934–941, 2002. © 2002 Wiley‐Liss, Inc.

A new method was investigated for improving the efficiency of ECG‐gated coronary magnetic resonance angiography (CMRA) by accurate, automated tracking of the vessel motion over the cardiac cycle. Vessel tracking was implemented on a spiral gradient‐echo pulse sequence with sub‐millimeter in‐plane spatial resolution as well as high image signal to noise ratio. Breath hold 2D CMRA was performed in 18 healthy adult subjects (mean age 46 ± 14 years). Imaging efficiency, defined as the percentage of the slices where more than 30 mm of the vessel is visualized, was computed in multi‐slice spiral scans with and without vessel tracking. There was a significant improvement in the efficiency of the vessel tracking sequence compared to the multi‐slice sequence (56% vs. 32%, P< 0.001). The imaging efficiency increased further when the true motion of the coronary arteries (determined using a cross correlation algorithm) was used for vessel tracking as opposed to a linear model for motion (71% vs. 57%, P< 0.05). The motion of the coronary arteries was generally found to be linear during the systolic phase and nonlinear during the diastolic phase. The use of subject‐tailored, automated tracking of vessel positions resulted in improved efficiency of coronary artery illustration on breath held 2D CMRA. J. Magn. Reson. Imaging 2001;14:368–373. Published 2001 Wiley‐Liss, Inc.

Cardiac and respiratory motion present significant challenges for MR coronary angiography, which have not been completely resolved to date by either breath‐holding or respiratory navigation. Adaptive averaging during real‐time MRI may provide a useful alternative to these techniques. In this method, cross‐correlation is used to automatically identify those real‐time imaging frames in which the vessel is present, and to determine the location of the vessel within each frame. This information is then used for selective averaging of frames to increase the signal‐to‐noise ratio and to improve visualization of the vessel. The correlation theorem was employed to raise the speed of this algorithm by up to two orders of magnitude. Segmenting data collection and reconstruction into subimages allows the extension of this technique to higher spatial resolution. Adaptive averaging provides a robust method for coronary MRI which requires no breath‐holding, navigation, or ECG gating. Magn Reson Med 44:940–946, 2000. © 2000 Wiley‐Liss, Inc.

Cardiac and respiratory motion present significant challenges for MR coronary angiography, which have not been completely resolved to date by either breath-holding or respiratory navigation. Adaptive averaging during real-time MRI may provide a useful alternative to these techniques. In this method, cross-correlation is used to automatically identify those real-time imaging frames in which the vessel is present, and to determine the location of the vessel within each frame. This information is then used for selective averaging of frames to increase the signal-to-noise ratio and to improve visualization of the vessel. The correlation theorem was employed to raise the speed of this algorithm by up to two orders of magnitude. Segmenting data collection and reconstruction into subimages allows the extension of this technique to higher spatial resolution. Adaptive averaging provides a robust method for coronary MRI which requires no breath-holding, navigation, or ECG gating. Magn Reson Med 44:940–946, 2000. © 2000 Wiley-Liss, Inc.