MIMOSA: Multi-parametric Imaging using Multiple-echoes with Optimized Simultaneous Acquisition for highly-efficient quantitative MRI.

Purpose: To develop a new sequence, MIMOSA, for highly-efficient T1, T2, T2*, proton density (PD), and source separation quantitative susceptibility mapping (QSM).

Methods: MIMOSA was developed based on 3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) by combining 3D turbo Fast Low Angle Shot (FLASH) and multi-echo gradient echo acquisition modules with a spiral-like Cartesian trajectory to facilitate highly-efficient acquisition. Simulations were performed to optimize the sequence.

Brain morphometry and chronic inflammation in Bangladeshi children growing up in extreme poverty.

Over three hundred million children live in environments of extreme poverty, and the biological and psychosocial hazards endemic to these environments often expose these children to infection, disease, and inflammatory responses. Chronic inflammation in early childhood has been associated with diminished cognitive outcomes, and despite this established relationship, the mechanisms explaining how inflammation affects brain development are not well known. Importantly, the prevalence of chronic inflammation in areas of extreme poverty raises the possibility that it may also serve as a mechanism explaining the known relationship between low socioeconomic status (SES) and altered brain development.

Vendor-agnostic 3D multiparametric relaxometry improves cross-platform reproducibility.

Purpose: To address the unmet need for a cross-platform, multiparametric relaxometry technique to facilitate data harmonization across different sites.

Methods: A simultaneous T and T mapping technique, 3D quantification using an interleaved Look-Locker acquisition sequence with a T preparation pulse (3D-QALAS), was implemented using the open-source vendor-agnostic Pulseq platform. The technique was tested on four 3 T scanners from two vendors across two sites, evaluating cross-scanner, cross-software version, cross-site, and cross-vendor variability.

Design and rationale of "Antecedents and correlates of well-being in young adults with congenital heart disease in the Boston Circulatory Arrest Study (BCAS-adult)".

Objectives: Neurodevelopmental challenges are common among children and adolescents with congenital heart disease (CHD), affecting up to 50% of patients, and recent data suggests they are also present in adulthood. Longitudinal predictors of these challenges in adults have not been studied. The goal of this study was to assess well-being in adults with D-transposition of the great arteries (d-TGA) who had been enrolled in the Boston Circulatory Arrest Study (BCAS) where developmental follow-up was reported throughout childhood and adolescence with brain MRI imaging correlation in adolescence.

Comparison of test-retest repeatability of DESPOT and 3D-QALAS for T and T mapping.

Background: Relaxometry, specifically T and T mapping, has become an essential technique for assessing the properties of biological tissues related to various physiological and pathological conditions. Many techniques are being used to estimate T and T relaxation times, ranging from the traditional inversion or saturation recovery and spin-echo sequences to more advanced methods. Choosing the appropriate method for a specific application is critical since the precision and accuracy of T and T measurements are influenced by a variety of factors including the pulse sequence and its parameters, the inherent properties of the tissue being examined, the magnetic resonance imaging (MRI) hardware, and the image reconstruction.

Fetal MRI: Radiofrequency Safety Assessment at 3 Tesla.

Background: 3-T MRI can improve image quality of fetal imaging compared to 1.5-T MRI. However, concerns exist regarding increased local tissue heating at 3-T.

Reduced Cerebellar Volumes Associate with P300 Amplitude Attenuation in Children with Clinical High Risk for Psychosis and Early Onset Psychosis.

Patients with psychotic illnesses, including early onset psychosis (EOP), often experience cognitive impairment. The cerebellum is critically involved in neurocognitive processes, yet possible regional alterations in the cerebellum and their associations with behavioral parameters remain largely unexplored in EOP. In this preliminary study, we aimed to investigate structural morphological properties of the cerebellum as well as the supratentorial brain, and how morphological changes in the central nervous system relate to neurocognitive performance in children with EOP and clinical high-risk for psychosis (CHR).

Quantifying brain development in the HEALthy Brain and Child Development (HBCD) Study: The magnetic resonance imaging and spectroscopy protocol.

The HEALthy Brain and Child Development (HBCD) Study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. The acquisition of multimodal magnetic resonance-based brain development data is central to the study's core protocol. However, application of Magnetic Resonance Imaging (MRI) methods in this population is complicated by technical challenges and difficulties of imaging in early life.

Comparison of test-retest reproducibility of DESPOT and 3D-QALAS for water and mapping.

Purpose: Relaxometry, specifically and mapping, has become an essential technique for assessing the properties of biological tissues related to various physiological and pathological conditions. Many techniques are being used to estimate and relaxation times, ranging from the traditional inversion or saturation recovery and spin-echo sequences to more advanced methods. Choosing the appropriate method for a specific application is critical since the precision and accuracy of and measurements are influenced by a variety of factors including the pulse sequence and its parameters, the inherent properties of the tissue being examined, the MRI hardware, and the image reconstruction.

Time-division multiplexing (TDM) sequence removes bias in T estimation and relaxation-diffusion measurements.

Purpose: To compare the performance of multi-echo (ME) and time-division multiplexing (TDM) sequences for accelerated relaxation-diffusion MRI (rdMRI) acquisition and to examine their reliability in estimating accurate rdMRI microstructure measures.

Method: The ME, TDM, and the reference single-echo (SE) sequences with six TEs were implemented using Pulseq with single-band (SB) and multi-band 2 (MB2) acceleration factors. On a diffusion phantom, the image intensities of the three sequences were compared, and the differences were quantified using the normalized RMS error (NRMSE).

Integrated Short-TE and Hadamard-edited Multi-Sequence (ISTHMUS) for advanced MRS.

Background: To examine data quality and reproducibility using ISTHMUS, which has been implemented as the standardized MR spectroscopy sequence for the multi-site Healthy Brain and Child Development (HBCD) study.

Methods: ISTHMUS is the consecutive acquisition of short-TE PRESS (32 transients) and long-TE HERCULES (224 transients) data with dual-TE water reference scans. Voxels were positioned in the centrum semiovale, dorsal anterior cingulate cortex, posterior cingulate cortex and bilateral thalamus regions.

Insights from serial magnetic resonance imaging in neonatal encephalopathy in term infants.

Background: Limited serial neuroimaging studies use magnetic resonance imaging (MRI) to define the evolution of hypoxic-ischemic insults to the brain of term infants and encompass both the primary injury and its secondary impact on cerebral development. The optimal timing of MRI to fully evaluate the impact of hypoxic-ischemic encephalopathy on brain development and associated neurodevelopmental sequelae remains unknown.

Methods: Goals: (a) review literature related to serial neuroimaging in term infants with HIE; (b) describe pilot data in two infants with HIE treated with therapeutic hypothermia who had a brain injury at day 3-5 and underwent four additional MRIs over the next 12 weeks of life and developmental evaluation at 24 months of age.

Time-division multiplexing (TDM) sequence removes bias in T2 estimation and relaxation-diffusion measurements.

Purpose: To compare the performance of multi-echo (ME) and time-division multiplexing (TDM) sequences for accelerated relaxation-diffusion MRI (rdMRI) acquisition and to examine their reliability in estimating accurate rdMRI microstructure measures.

Method: The ME, TDM, and the reference single-echo (SE) sequences with six echo times (TE) were implemented using Pulseq with single-band (SB-) and multi-band 2 (MB2-) acceleration factors. On a diffusion phantom, the image intensities of the three sequences were compared, and the differences were quantified using the normalized root mean squared error (NRMSE).

SE(3)-Equivariant and Noise-Invariant 3D Rigid Motion Tracking in Brain MRI.

Rigid motion tracking is paramount in many medical imaging applications where movements need to be detected, corrected, or accounted for. Modern strategies rely on convolutional neural networks (CNN) and pose this problem as rigid registration. Yet, CNNs do not exploit natural symmetries in this task, as they are equivariant to translations (their outputs shift with their inputs) but not to rotations.

Integrated Short-TE and Hadamard-edited Multi-Sequence (ISTHMUS) for Advanced MRS.

Background: To examine data quality and reproducibility using ISTHMUS, which has been implemented as the standardized MR spectroscopy sequence for the multi-site Healthy Brain and Child Development (HBCD) study.

Methods: ISTHMUS is the consecutive acquisition of short-TE PRESS (32 transients) and long-TE HERCULES (224 transients) data with dual-TE water reference scans. Voxels were positioned in the centrum semiovale, dorsal anterior cingulate cortex, posterior cingulate cortex and bilateral thalamus regions.

Reduced cross-scanner variability using vendor-agnostic sequences for single-shell diffusion MRI.

Purpose: To reduce the inter-scanner variability of diffusion MRI (dMRI) measures between scanners from different vendors by developing a vendor-neutral dMRI pulse sequence using the open-source vendor-agnostic Pulseq platform.

Methods: We implemented a standard EPI based dMRI sequence in Pulseq. We tested it on two clinical scanners from different vendors (Siemens Prisma and GE Premier), systematically evaluating and comparing the within- and inter-scanner variability across the vendors, using both the vendor-provided and Pulseq dMRI sequences.

Design and Harmonization Approach for the Multi-Institutional Neurocognitive Discovery Study (MINDS) of Adult Congenital Heart Disease (ACHD) Neuroimaging Ancillary Study: A Technical Note.

Dramatic advances in the management of congenital heart disease (CHD) have improved survival to adulthood from less than 10% in the 1960s to over 90% in the current era, such that adult CHD (ACHD) patients now outnumber their pediatric counterparts. ACHD patients demonstrate domain-specific neurocognitive deficits associated with reduced quality of life that include deficits in educational attainment and social interaction. Our hypothesis is that ACHD patients exhibit vascular brain injury and structural/physiological brain alterations that are predictive of specific neurocognitive deficits modified by behavioral and environmental enrichment proxies of cognitive reserve (e.

Time-efficient, high-resolution 3T whole-brain relaxometry using 3D-QALAS with wave-CAIPI readouts.

Purpose: Volumetric, high-resolution, quantitative mapping of brain-tissue relaxation properties is hindered by long acquisition times and SNR challenges. This study combines time-efficient wave-controlled aliasing in parallel imaging (wave-CAIPI) readouts with the 3D quantification using an interleaved Look-Locker acquisition sequence with a T preparation pulse (3D-QALAS), enabling full-brain quantitative T , T , and proton density (PD) maps at 1.15-mm isotropic voxels in 3 min.

Single Ventricle Reconstruction III: Brain Connectome and Neurodevelopmental Outcomes: Design, Recruitment, and Technical Challenges of a Multicenter, Observational Neuroimaging Study.

Unlabelled: Patients with hypoplastic left heart syndrome who have been palliated with the Fontan procedure are at risk for adverse neurodevelopmental outcomes, lower quality of life, and reduced employability. We describe the methods (including quality assurance and quality control protocols) and challenges of a multi-center observational ancillary study, SVRIII (Single Ventricle Reconstruction Trial) Brain Connectome. Our original goal was to obtain advanced neuroimaging (Diffusion Tensor Imaging and Resting-BOLD) in 140 SVR III participants and 100 healthy controls for brain connectome analyses.

NeSVoR: Implicit Neural Representation for Slice-to-Volume Reconstruction in MRI.

Reconstructing 3D MR volumes from multiple motion-corrupted stacks of 2D slices has shown promise in imaging of moving subjects, e. g., fetal MRI.