multi directional diffusion weighting  (Siemens AG)

Journal: Magnetic Resonance in Medicine

Article Title: Motion‐Compensated Diffusion Imaging With Phase‐Contrast for Robust Quantification of Regional Cerebral Blood Flow

doi: 10.1002/mrm.70324

Figure Lengend Snippet: Schematic diagram of the analytical procedure for the motion‐compensated diffusion imaging with phase‐contrast (MC‐DIP). (A) Data acquisition: Diffusion‐weighted imaging (DWI) with multiple b ‐values is acquired using three gradient schemes (2nd‐MC, 1st‐MC, and non‐MC), along with phase‐contrast (PC) MRI of the internal carotid arteries (ICAs) and vertebral arteries (VAs). (B) Biexponential diffusion analysis: The DWI data are processed using a stepwise biexponential fitting to estimate the true diffusion coefficient ( D ), perfusion‐related diffusion coefficient ( D *), and perfusion fraction ( F ), from which a relative perfusion map ( FD *) is calculated. (C) Absolute regional cerebral blood flow (rCBF) calculation: The PC‐MRI data are used to calculate total cerebral blood flow (tCBF). A conversion factor is determined by dividing tCBF by the whole‐brain sum of FD * values. The final absolute rCBF map is then generated by multiplying the FD * map by this conversion factor.

Article Snippet: The motion‐compensated diffusion sequence used in this research was provided by Philips as part of a research agreement.

Techniques: Diffusion-based Assay, Imaging, Generated

Journal: Magnetic Resonance in Medicine

Article Title: Motion‐Compensated Diffusion Imaging With Phase‐Contrast for Robust Quantification of Regional Cerebral Blood Flow

doi: 10.1002/mrm.70324

Figure Lengend Snippet: Representative rCBF maps from a single subject obtained using the three different DIP schemes and the reference ASL method. The non‐MC‐DIP shows prominent artifacts (areas of artificially high signal, red). These artifacts are partially reduced with 1st‐MC and most effectively suppressed with 2nd‐MC, resulting in maps with spatial distribution and contrast comparable to the ASL reference. rCBF, regional cerebral blood flow; MC‐DIP, motion‐compensated diffusion imaging with phase‐contrast; ASL, arterial spin labeling.

Article Snippet: The motion‐compensated diffusion sequence used in this research was provided by Philips as part of a research agreement.

Techniques: Diffusion-based Assay, Imaging, Labeling

Journal: Magnetic Resonance in Medicine

Article Title: Motion‐Compensated Diffusion Imaging With Phase‐Contrast for Robust Quantification of Regional Cerebral Blood Flow

doi: 10.1002/mrm.70324

Figure Lengend Snippet: Comparison of biexponential fitting accuracy, as measured by the normalized root mean squared error (nRMSE), for (A) gray matter (GM) and (B) white matter (WM). The boxplots compare the second‐order motion‐compensated (2nd‐MC), first‐order motion‐compensated (1st‐MC), and non‐compensated (non‐MC) schemes. In GM, both the 1st‐MC and 2nd‐MC schemes were superior to the non‐MC scheme. In WM, however, only the 2nd‐MC scheme significantly reduced the fitting error compared with both other methods.

Article Snippet: The motion‐compensated diffusion sequence used in this research was provided by Philips as part of a research agreement.

Techniques: Comparison

Journal: Magnetic Resonance in Medicine

Article Title: Motion‐Compensated Diffusion Imaging With Phase‐Contrast for Robust Quantification of Regional Cerebral Blood Flow

doi: 10.1002/mrm.70324

Figure Lengend Snippet: Scatter plots showing the correlation between DIP‐ and ASL‐derived rCBF in gray matter (GM; top row, A–C) and white matter (WM; bottom row, D–F). Each data point represents the mean rCBF value for each subject ( n = 11). The plots correspond to the second‐order motion‐compensated (2nd‐MC; A, D), first‐order motion‐compensated (1st‐MC; B, E), and non‐compensated (non‐MC; C, F) schemes. Spearman's correlation coefficients ( ρ ) and p values are shown. While all schemes correlated with ASL in GM, only the 2nd‐MC scheme established a significant correlation in WM. DIP, diffusion imaging with phase‐contrast; ASL, arterial spin labeling; rCBF, regional cerebral blood flow.

Article Snippet: The motion‐compensated diffusion sequence used in this research was provided by Philips as part of a research agreement.

Techniques: Derivative Assay, Diffusion-based Assay, Imaging, Labeling

Journal: Brain Structure & Function

Article Title: Topographic organisation of the claustrum–amygdala–prefrontal circuitry in the common marmoset ( Callithrix jacchus )

doi: 10.1007/s00429-025-03026-z

Figure Lengend Snippet: Connectivity between the amygdala and the claustrum complex. A Coronal sections from Case F15 following a biotinylated dextran amine (BDA) injection into the basolateral amygdala complex (BLC), showing retrogradely labelled cell bodies (red) and terminal axon fields (pink) within the claustrum complex. The insular claustrum (IC) is outlined in blue; the dorsal endopiriform nucleus [dorsal (DEnD), intermediate (DEnI), and ventral (DEnV) subdivisions] in yellow. B Streamline endpoint maps derived from the population template of diffusion-weighted tractography (Marmoset Brain Mapping Atlas), showing streamline endpoints from lateral (LA), basolateral (BL), and basomedial (BM) amygdala subnuclei - claustrum streamlines in the claustrum complex. C Left: anatomical parcellation of LA, (BL, and (BM amygdala subnuclei based on T2*-weighted MRI represented in 3D space with orientation (R; right, L; left, S; superior, I; inferior). Right: distribution of BLC–claustrum streamline endpoints along the anterior–posterior (A-P) axis of the claustrum complex

Article Snippet: The marmosets were scanned in a two-dimensional diffusion-weighted spin-echo echo-planar imaging sequence on a 7T horizontal MRI (Bruker, Billerica, USA) equipped with a 30-mm quadrature coil and a 15 cm customized gradient set capable of 450 mT/m gradient strength.

Techniques: Injection, Derivative Assay, Diffusion-based Assay