bluuebunny/crossref_metadata_2025 huggingface dataset:
Longitudinal metabolic assessment for neonatal ischemic stroke in rat brain using CEST-MRI
Authors: Ma Lele , Xia Qianqian , Li Yifan , Jia Wentao , Ma Zhao , Wang Yuqin , Hou Xinlin , Song Xiaolei
Published: November 2024

Motivation: Chemical exchange saturation transfer (CEST) has been employed for studying pH changes in acute phase of neonatal arterial ischemic stroke (NAIS), but not for long-term effects. Goal(s): This study aimed to achieve longitudinal monitoring of NAIS evolution. Approach: We constructed a 7-day-old NAIS rat model and explored the changes of brain metabolites by CEST-MRI. Contrast maps for contributing metabolites were calculated using Lorentzian Difference (LD) methods. Results: All LD-quantified CEST contrast maps exhibit significant increase as age growth, in both sham group and the contralateral brain in NAIS group; Whereas the ischemic hemisphere displayed lower signals than the contralateral sides in NAIS group . Impact: CEST signals displayed significant elevation over from 3h to 5w after surgery for both sham group and the contralateral brain tissue in NAIS group. This suggests the potential of CEST in sensitive and comprehensive assessment in NAIS diagnosis and management.
Early diagnosis and prognosis of full-term neonatal hypoxic-ischemic encephalopathy using 3D arterial spin labeling perfusion imaging
Authors: Liu Chang , Liu Ranzhu , Zhang Yong
Published: November 2024

Motivation: Hypoxic ischemic encephalopathy (HIE) is the most important reason for morbidity and mortality in full-term infants. Goal(s): This study aimed to investigate the clinical value of 3DASL perfusion imaging for the early diagnosis and prognosis of HIE in full-term neonates. Approach: This study recruited 40 full-term HIE neonates and 40 healthy controls. Cerebral blood flow (CBF) values of bilateral frontal lobes, basal ganglia, thalamus were measured for comparison. Results: The HIE groups showed significant decreased CBF values in the frontal lobes but significantly increased CBF values in basal ganglia and thalamus as compared to the control group. Impact: We observed significant group differences between HIE neonates and healthy controls. 3DASL could reflect abnormal changes of cerebral perfusion in HIE infants and demonstrated the clinical value for early diagnosis and diagnosis of HIE.
Dose-Dependent Effects of Preterm Birth and Brain Injury on Superficial White Matter Microstructure and Development
Authors: Yu Qiaowen , Gao Jie
Published: November 2024

Motivation: As the last myelinated structure, SWM is most affected by prematurity. Early exposure to the environment might injure the organization of SWM and lead to psychiatric disorders later in life. Goal(s): To detect the impact of both preterm birth and “abnormal” brain injury on SWM microstructure. Approach: TBSS method was used to track SWM in preterm infants of different degrees. The study aimed to detect changes in diffusion indices over time and identify distinct manifestations within the brain injury group. Results: We were surprised to find that different degrees of preterm birth have different effects on the microstructure of superficial white matter. Impact: The dose-dependent effect of preterm birth on SWM microstructure/developmental pattern. Further study the dynamic developmental association between SWM structure and neurodevelopmental outcomes in elderly children to gain a deeper understanding of the role of SWM in brain functional development.
Assessing High-Risk Pregnancy Impact on Premature Infant Brain Development Using Synthetic MRI and Doppler Ultrasound
Authors: lv qingqing
Published: November 2024

Motivation: To explore high-risk pregnancy effects on premature infant brain development. Conditions like preeclampsia, gestational diabetes, and thyroid dysfunction can profoundly impact fetal brain development. Goal(s): To evaluate the correlation between synthetic MRI and Doppler ultrasound in assessing brain development in high-risk pregnancies. Approach: 54 infants from high-risk pregnancies and 50 from low-risk pregnancies were studied, analyzing various brain regions and blood flow parameters. Results: Findings indicate moderate correlations between synthetic MRI and Doppler ultrasound data, providing a comprehensive assessment of premature infant brain development in high-risk pregnancies, with specific MRI and blood flow correlations. Impact: This study's findings expand our understanding of high-risk pregnancy effects on infant brain development. They offer clinicians a valuable tool for early intervention, potentially improving outcomes for premature infants born to high-risk mothers.
Detecting silent lesions in hypoxic-ischemic encephalopathy using submillimeter isotropic resolution diffusion MRI
Authors: Xu Runze , Liao Yi , Chen Xijian , Zhu Juncheng , Sun Yan , Qu Haibo
Published: November 2024

Motivation: MRI is crucial for the diagnosis and prognosis of hypoxic-ischemic encephalopathy (HIE). High-resolution imaging benefits the detection of subtle lesions. However, neonates may not tolerate lengthy scans . Goal(s): To obtain ultrahigh resolution brain diffusion-weighted MR images(DWIs) within a feasible time frame to detect lesions invisible on images acquired using standard clinical protocols. Approach: One b=0 volume and six DWI volumes at submillimeter isotropic resolution (0.86×0.86×0.86 mm3) were acquired using the Generalized SLIce Dithered Enhanced Resolution Simultaneous MultiSlice (gSlider-SMS) sequence, in addition to standard protocols. Results: Ischemic lesions and cytotoxic edema invisible on standard clinical images were found on submillimeter resolution diffusion MRI data. Impact: Submillimeter isotropic resolution diffusion MR images show lesions invisible on standard clinical images, which helps diagnose HIE earlier and more accurately for timely and appropriate treatment, as well as provides new biomarkers for accurate HIE staging.
Synthetic MRI in Evaluating Neonatal Hyperbilirubinemia: a Feasibility Study
Authors: Zhu Qing , Tang Wenwei , Tian Zhongfu , Wang Lili , Pylypenko Dmytro
Published: November 2024

Motivation: Brain injury induced by neonatal hyperbilirubinemia is an important cause of abnormal development of infant nervous system. The traditional use of serum total bilirubin as a diagnostic marker is inconsistent and imprecise. Goal(s): This study aims to investigate the relationship between different levels of bilirubin and quantitative parameters of SyMRI with hyperbilirubinemia. Approach: A total of 107 NHB and 22 healthy infants were recruited in the study. Obtain T1, T2, and PD values by scanning SyMRI sequences. Results: There were significant difference in T1 values of globus pallidus and cerebral peduncle at different levels of TSB, and there were negative correlation. Impact: The assessment of neonatal bilirubin encephalopathy with increased signals from the pallidus has a high degree of subjectivity. SyMRI can reflect biological information through quantitative parameters, providing objective basis for the early diagnosis of NHB.
Motion Detection in Neonatal MR Fingerprinting: Enhancing Reliability in T1 and T2 values
Authors: Kato Ayumi , Aida Noriko , Murata Katsutoshi , Nittka Mathias , Koerzdoerfer Gregor , Utsunomiya Daisuke
Published: November 2024

Motivation: Motion artifact of MR Fingerprinting (MRF) cannot be recognized visually, but it affects quantitative values severely. Goal(s): We aimed to assess the impact of motion in MRF and propose an objective motion-detection method. Approach: We utilized Spatiotemporal Residuals (STR) from MRF-acquired signals and compared them with motion assessments in neonatal clinical practice. Results: Our results revealed that motion significantly affects the accuracy of both T1 and T2 values. By applying an appropriate threshold to the standard deviation of STR, we achieved highly accurate motion detection equivalent to expert visual judgment, which leads to robust accuracy of quantitative values. Impact: Our method to detect motion from MRF signals enables an objective assessment of the presence or absence of motion in MRF data. Consequently, this method facilitates the evaluation of the reliability of quantitative MRF images in clinical settings.
Microstructural cortical maturation underlies longitudinal BOLD signal variability of emerging resting-state networks in preterm infants
Authors: de Almeida Joana Sa , Loukas Serafeim , Boehringer Andrew , Van Der Veek Annemijn , Lordier Lara , Courvoisier Sebastien , Lazeyras François , Van de Ville Dimitri , Huppi Petra
Published: November 2024

Motivation: BOLD signal variability (BOLD-SD) has emerged as a measure for assessing brain function, but little is known regarding its biological significance. Goal(s): Demonstrate that cortical BOLD-SD modifications are accompanied by structural intracortical maturational changes. Elucidate brain networks undergoing the most important maturational changes during early development. Approach: Longitudinal brain MRI acquisition in preterm infants at 33 and 40 weeks’ gestational age. Assessment of cortical BOLD-SD and NODDI indices longitudinal modifications per brain network. Results: A significant longitudinal cortical BOLD-SD increase is observed in primary sensory networks and Default-Mode-Network, accompanied by a decreased NDI (neurite-density-index) and/or increased ODI (orientation-dispersion-index), reflecting concomitant structural intracortical maturation. Impact: During early brain development, the BOLD signal variability increase in resting-state networks was associated to underlying structural intracortical maturational changes and thus it can be considered as a marker of cortical maturation.
The cumulative impact of clinical risk factors on structural brain networks and executive functions in adolescents with congenital heart disease
Authors: Ehrler Melanie , Speckert Anna , Kretschmar Oliver , O’Gorman Ruth Tuura , Latal Beatrice , Jakab Andras
Published: November 2024

Motivation: Congenital heart disease (CHD) negatively impacts brain development and cognition. Goal(s): We aim to elucidate the role of clinical and environmental factors on brain development and cognition. Approach: A cumulative clinical risk (CCR) score derived from neonatal, cardiac, and neurological variables, brain connectivity metrics using diffusion-MRI, and cognitive outcomes were obtained in 53 CHD adolescents and 75 controls. Results: Higher CCR scores correlated with weaker brain network strength in a fronto-parietal-thalamic network, lower network segregation and poorer cognitive function, independent of family-environmental factors. These findings underscore the need for early risk assessment to predict brain development and aid vulnerable adolescents with CHD. Impact: Adolescents with congenital heart disease demonstrate altered brain networks, particularly those who face a cumulative exposure to multiple risk factors over time. Early assessment of risk load could help predict brain development and support the most vulnerable patients early on.
Developmental Changes of N-Acetyl-Aspartyl-Glutamate (NAAG) in the Human Brain
Authors: Blüml Stefan , Saunders Alexander , Tamrazi Benita , Nelson Marvin
Published: November 2024

Motivation: N-acetyl-aspartyl-glutamate (NAAG) is a dipeptide and glutamate neuromodulator with possible significance as therapeutical target for injuries and diseases associated with glutamate neurotoxicity. Goal(s): Determine age-dependent differences in its accumulation in white and grey matter in the human brain. Approach: Existing MR spectra from 410 “closest-to-normal” pediatric patients and controls were evaluated. Results: NAAG concentrations in the human brain were low and borderline detectable from birth to early childhood but then increased in late childhood in the parietal white matter whereas NAAG remained low in parietal grey matter. Impact: This study demonstrates that NAAG accumulates at late childhood predominantly in WM. Furthermore, it suggests that in vivo MRS can be used to assess NAAG levels in disorders associated with excessive glutamatergic neurotransmission, such as childhood seizures.
Comparative Analysis of Three Rapid T1WI Imaging Techniques in Fetal Gastrointestinal Magnetic Resonance Imaging
Authors: Zhao Meng , Zeng Yijia , Zhang Runtong , He Jingzhen , Cheng Qichao , Xin Jiaxiang , Xue Lei
Published: November 2024

Motivation: In the prenatal diagnosis of gastrointestinal abnormality,fetal magnetic resonance imaging (MRI) is becoming increasingly relevant. Goal(s): T1-weighted sequences enable assessment of the presence of meconium, allowing diagnosis of gastrointestinal abnormality, a method with a higher success rate and better image quality is necessary. Approach: In this work, we compared the performance of three rapid 3D T1-weighted imaging sequences for fetal gastrointestinal MRI at 1.5 T MRI scanner, including free-breathing radial and breath-hold, as well as the free-breathing multi-average 3D VIBE sequences. Results: Our results demonstrated that free-breathing multi-average VIBE sequence not only demonstrates a higher success rate but also delivers superior image quality. Impact: The T1WI images of fetal gastrointestinal were barely satisfactory , which accompanied by motion and other artifacts. It is necessary to find a scanning method that is tolerable to the mother and has good image quality.
Brain Microstructural Changes in Children with Infantile Tremor Syndrome After Vitamin-B12 Intervention Using Diffusion Tensor Imaging
Authors: Salan Teddy , Kumar Pawan , Dash Sanket , Govind Varan , Vyas Sameer , Sankhyan Naveen
Published: November 2024

Motivation: Infantile Tremor syndrome (ITS) is a neurocutaneous syndrome observed in infants breastfed by vegetarian mothers who are deficient in vitamin B12. Its is accompanied by cerebral and white matter atrophy, delayed myelination, and delayed neurodevelopment. Goal(s): To evaluate the efficacy of B12 treatment in infants with ITS on microstructural development and myelination using DTI. Approach: In this longitudinal study, changes in DTI metrics are evaluated before and after vitamin B12 treatment using an atlas-based approach. Results: Results show substantial increases in WM FA and decrease in WM RD, as evidence of the role of B12 in the myelination process. Impact: Our findings will contribute to understanding the pathophysiological basis of ITS and highlight the efficacy of B12 treatment in rapidly reversing delayed brain development
Prenatal Associations of Maternal Psychological State with Infant Gray Matter Microstructure
Authors: DiPiero Marissa , Rodrigues Patrik Goncalves , Justman Mckaylie , Roche Sophia , Bond Elizabeth , Gonzalez Jose Guerrero , Dean Douglas
Published: November 2024

Motivation: Given known associations between maternal distress during pregnancy and increased risk of offspring to develop psychopathology, it is critical to assess the influences of prenatal maternal depression & anxiety (pMDA) on infant brain organization. Goal(s): To investigate the relationship between pMDA and GM organization and assess differences in this relationship between male and female infants. Approach: In this study, we apply the NODDI GM- Based Spatial Statistics framework adapted for the infant brain to assess the relationship with pMDA and infant GM organization and investigate sex-related differences within this relationship. Results: Our findings suggest a sex-dependent association between pMDA and infant GM microstructure. Impact: Results may inform the development of interventions for maternal support during pregnancy.
Associations Between Neurometabolite Levels and Sleep Quality in Survivors of Pediatric Hodgkin Lymphoma (HL)
Authors: Gibney Kyla , Nisar Sabah , Chakraborty Kasturee , Hanby Pat , Hudson Melissa , Ness Kirsten , Mandrell Belinda , Krull Kevin , Bagga Puneet
Published: November 2024

Motivation: Survivors of pediatric Hodgkin’s lymphoma (HL) have excessive daytime sleepiness and fatigue, with substantial consequences to quality of life. Thoracic radiation therapy (TRT), traditionally used to treat HL, is associated with cardiopulmonary morbidity and may result in sleep apnea. Goal(s): Although sleep is known to impact neurometabolites in the general population, its effect on neurometabolite concentrations in HL survivors has not been established. Approach: The present study used magnetic resonance spectroscopy (MRS) to explore the relationship between neurometabolites and sleep quality in pediatric HL survivors and community controls. Results: We found associations between metabolites associated with excitotoxicity and neuroinflammation with sleep and age. Impact: Our findings may identify therapeutic targets for interventions that mitigate the treatment-related late effects commonly experienced by HL survivors. Our results suggest that excitotoxicity and neuroinflammation could mediate the impact of sleep disturbances on age-associated late effects of cancer treatment.
Lactate and total choline show potential prognostic values in diffuse intrinsic pontine glioma
Authors: Pavao Esther , Burman Ritambhar , Burns Andrew , Wang Shubo , Pinto Soniya , Zhang Silu , Scoggins Matthew , Sanchez-Hernandez Laura , Bagga Puneet
Published: November 2024

Motivation: Metabolic mapping in Diffuse intrinsic pontine glioma (DIPG) may indicate prognosis and potential therapeutic targets. Goal(s): We intended to identify metabolic ratios that indicated dysregulated metabolic pathways using 1H-MRS and determine whether these metabolites are associated with overall survival length. Approach: We performed CSI in patients with DIPG prior to radiation therapy. Then we assessed the predictive value of a metabolite ratio for patient overall survival. Results: Lactate and total choline levels were found to be significantly associated with patient overall survival, making them potential prognostic predictors of overall survival in DIPG. Impact: This study shows that more aggressive DIPGs are metabolically distinct from less aggressive tumors and that the metabolic differences can predict the overall survival of patients.
Changes in Working Memory Structural Connectomes During Reduced Intensity Therapy for WNT-subtype Medulloblastoma
Authors: Reddick Wilburn , Raja Rajikha , Song Ruitian , Glass John , Bag Asim , Sabin Noah , Patni Tushar , Li Yimei , Conklin Heather , Ashford Jason , Onar-Thomas Arzu , Merchant Thomas , Gajjar Amar , Robinson Giles
Published: November 2024

Motivation: Cognitive impairment following treatment of medulloblastoma has been associated with white matter structural changes and altered structural brain connectivity. Goal(s): We hypothesized that decreased intensity therapy would reduce acute change in the working memory structural connectome. Approach: Working memory structural connectomes were assessed relative to baseline after 15 Gy craniospinal irradiation (RT), after subsequent reduced-intensity chemotherapy, and during follow-up for 24 children treated for WNT-subtype (WNT) medulloblastoma. Results: Changes after RT or chemotherapy showed small increases in connectivity strength in frontal striatal edges indicating little acute change. Follow-up revealed significant decreases in connectivity of the bilateral connections between caudate/thalamus. Impact: Increased connectivity of frontal striatal edges after therapy and decreased connectivity of caudate/thalamus edges in follow-up for patients receiving reduced intensity therapy for WNT medulloblastoma may indicate a low incidence of acute changes.
Diagnostic Value of Pulmonary MR Ultra-Short Echo Time (UTE) Imaging in Potential Pulmonary Metastasis in Pediatric Hepatoblastoma
Authors: Qian Li Jun , Gong Xu Hua , Zhang Ying , Wu Hua Wei , Yin Yan , Cao Ye , Zhu Yi , Song Yang , Feng Ming Xuan , Xu Jian Rong , Zhou Yan
Published: November 2024

Motivation: UTE MR has demonstrated its potential for evaluating pulmonary lesions, which could be employed for assessing pulmonary metastasis from hepatoblastoma. Goal(s): To investigate the diagnostic performance of UTE MR for detecting pulmonary nodules and thus diagnosing pulmonary metastasis in pediatric hepatoblastoma patients. Approach: Lung UTE was assessed for its capability to detect nodules and for its diagnostic performance for pulmonary metastasis. Results: UTE has a moderate diagnostic sensitivity for metastasis, while its specificity is high. When it comes to single pulmonary nodules, UTE has a moderate detection rate with a relatively high false positive detection rate. Impact: UTE has a moderate diagnostic sensitivity for pulmonary metastasis, while its specificity is high. To make MR imaging a reliable one-stop assessment tool, higher resolution UTE imaging technology will be needed in the future.
Comparison of water exchange measurements between filter-exchange and diffusion time-dependent kurtosis imaging in human brain
Authors: Li Zhaoqing , Feiweier Thorsten , Hsu Yi-Cheng , Bai Ruiliang
Published: November 2024

Motivation: Trans-membrane water exchange rate has been measured by several MRI methods but reported with largely variant results. Goal(s): To explore whether Filter-exchange imaging (FEXI) and time-dependent DKI are comparable for water exchange measurements on the same subjects in human brain. Approach: Eight healthy volunteers underwent FEXI and DKI(t) acquisitions on a 3T scanner. ROI-based analysis was performed to determine correlations between FEXI-derived AXR and DKI(t)-derived 1/τex. Results: A significant correlation between AXR and 1/τex was found only in axial direction in white matter. This correlation should be interpreted cautiously because structural disorder has non-negligible effects on D(t) and K(t) in Kärger model. Impact: While a significant correlation was observed between AXR and 1/τex in the axial direction, this study suggests cautious use of DKI(t) for water exchange measurements due to potential deviations from the Kärger model's constant diffusivity assumption in the human brain.
A GPU-Accelerated Software Toolbox for Simulation and Analysis of Diffusion MRI in Microstructures with a Graphical User Interface
Authors: Xu Junzhong , Jiang Xiaoyu , Devan Sean , Pamulaparthi Adithya , Yan Nicholas , Zu Zhongliang , Smith David , Harkins Kevin , Gore John
Published: November 2024

Motivation: Simulation and analysis of diffusion MRI (dMRI) in microstructures requires specialized expertise that limits its wide usage. Goal(s): To provide an easy-to-use dMRI software package to enable end users to simulate and analyze diffusion in complex media. Approach: MATI is written using object-oriented programming in two versions (MATLAB and Python) and can be used via a GUI or scripts. It can handle typical diffusion pulse sequences and various microstructures for data fitting, and arbitrary digitalized microstructures for simulating dMRI with GPU acceleration. Results: A GPU-accelerated dMRI simulation and data fitting toolbox with a GUI has been developed for public use. Impact: MATI, a GPU-accelerated toolbox for simulating and analyzing dMRI signals in various microstructures with a graphical user interface (GUI), has been developed. This easy-to-use package enables non-expert and expert users to simulate and analyze diffusion MRI signals in complex media.
The Pseudo-Fiber Effect: Fiber Density Impacts on Diffusion Metrics
Authors: Utt Kainen , Blum Jacob , Kim Eric , Ippolito Joseph , Rim Donsub
Published: November 2024

Motivation: To understand how axon density affects degeneracy-related errors in diffusion metric estimation. Goal(s): Assuming ideal conditions (e.g., noise free and no inter-compartmental exchange), are there correlations between voxel contents and model degeneracies? Approach: A systematically-generated set of simulated voxels spanning a wide range of microstructural compositions, processed with various diffusion models, and analyzed both comparatively and component-wise. Results: Based on the individual signal component results, the extra-axonal water is the largest confounding factor. A model's depends largely on its ability to distinguish truly intra-axonal water from constrained extra-axonal water. Impact: It is important to consider degeneracies when interpreting the results of diffusion modeling lest the associated errors propagate downstream. Our results offer a more robust understanding of the conditions which give rise to these degeneracy-related errors.
Toward optimal fitting parameters for multi-exponential DWI analysis of the kidney: A simulation study comparing different fitting algorithms
Authors: Jasse Jonas , Wittsack Hans-Jörg , Thiel Thomas , Zukovs Roman , Valentin Birte , Antoch Gerald , Ljimani Alexandra
Published: November 2024

Motivation: The use of multi-exponential signal analysis is common practice to identify present diffusion components in diffusion-weighted MRI. Yet, the absence of appropriate acquisition parameters and standardised signal analysis methods hinders the attainment of accurate results, especially in renal imaging. Goal(s): To assess the impact of fitting parameters and methods. Approach: A simulation was conducted comparing non-negative (NNLS) and non-linear (NLLS) fitting methods, but also determining ideal parameters for accurate in-vivo appliance. Results: The study showed superior accuracy when using the NNLS method in combination with area under curve (AUC) estimation and specified an optimized parameters set, improving clinical DWI examinations in kidneys. Impact: By employing our results, it is expected that stable and reliable results can be achieved in multi-exponential analysis of in-vivo DWI data using both NNLS and NLLS approaches. This will enable enhanced evaluation of clinical DWI examinations in the kidney.
Reduced Noise and Motion Artifacts for MUSE Reconstruction using Deep Learning-based Phase Correction
Authors: Lan Patricia , Wang Xinzeng , Guidon Arnaud
Published: November 2024

Motivation: Filter-based phase estimation requires tuning and is subject to the tradeoff between signal bias and vulnerability against phase inhomogeneity. DL-based phase correction has been shown to effectively remove both high- and low-frequency phase while minimizing signal bias. Goal(s): To evaluate a DL-based phase correction method that improves the robustness of motion-induced phase estimation and its impact on noise and motion artifacts in MUSE reconstruction. Approach: Volunteer brain and abdomen data were acquired with a MUSE sequence and reconstruction was performed offline. Results: Compared to filter-based phase estimation, DL-based phase correction results in reduced noise and motion artifacts in MUSE reconstructed images. Impact: MUSE enables high resolution DWI over a large FOV with reduced geometric distortion, but is very sensitive to shot-to-shot differences in motion-induced phase. DL-based phase correction can improve robustness in MUSE reconstruction, especially in anatomical regions with significant motion.
CATERPillar : a fast and flexible framework framework for generating synthetic white matter numerical phantoms
Authors: Nguyen-Duc Jasmine , de Riedmatten Ines , Cherchali Melina , Gardier Rémy , Lopez Jonathan Rafael Patiño , Jelescu Ileana
Published: November 2024

Motivation: Building realistic and complex white matter numerical phantoms is needed for accurate diffusion MRI simulations but challenging to achieve. Goal(s): The creation of white matter (WM) numerical phantoms by mimicking realisitic parallel axonal growth. Approach: This tool uses overlapping spheres to build realistic axons and parallels their growth to decrease the running time while reliably preventing collisions. Results: High intracellular volume fraction values can be reached (up to 70%) for tortuous, variable-caliber axons. The parallelism of the growth decreases the run-time. Impact: Creating numerical phantoms that accurately represent white matter can improve the accuracy of results in diffusion MRI studies using Monte Carlo simulations.
Short echo-time high-resolution diffusion imaging using multi-interleave spiral acquisition with simultaneous multi-slice (SMS) technique
Authors: Wu Zhe , Jaffray Alexander , Kasper Lars , Uludag Kamil
Published: November 2024

Motivation: Diffusion-weighted imaging (DWI) using spiral readout has higher signal-to-noise efficiency comparing to EPI approaches. Spiral DWI with a high spatial-resolution with improved image qualities is desirable for studies in fine-scale brain structures. Goal(s): The goal is to develop a short echo-time distortion-free diffusion imaging method with about 1 mm in-plane resolution with spiral readouts and simultaneous multi-slice (SMS) to accelerate acquisition. Approach: We developed a SMS multi-interleave spiral acquisition of DWI with gradient and B0 inhomogeneity corrections. The between-interleave phase error was corrected using a CG-SENSE method. Results: We demonsrated that a distortion-free short-TE high-resolution DWI using SMS multi-interleave spiral readout is feasible. Impact: A short echo-time multi-interleave spiral diffusion-weighted imaging (DWI) method with gradient and B0 inhomogeneity corrections without additional hardware is developed, leading to a high spatial-resolution DWI with an improved image quality for studies in fine-scale brain structures.
Deep learning constrained compressed sensing reconstruction for diffusion-weighted imaging in patients with breast cancers: a plot study
Authors: Hu Sixian , Yang Lanqing , Zhang Xiaoyong , Xia Chunchao , Li Zhenlin
Published: November 2024

Motivation: The challenges such as image quality and long scan time limitations have degraded the diffusion-weighted imaging (DWI) of breast cancer in clinical practice. Goal(s): This study aims to investigate the application of deep learning constrained compressed sensing (CS) reconstruction in DWI to overcome existing limitations. Approach: Quantitative and qualitative image quality of DWI and value apparent diffusion coefficient (ADC) of using CS (DWI-CS) and deep learning constrained CS (DWI-DLCS) were compared. Results: The results of DWI-DLCS exhibited better contrast, contrast-to-noise ratio (CNR), lesion detectability and diagnostic confidence. There were no differences regarding the signal intensity values of the apparent diffusion coefficient (ADC). Impact: Our study showcases the potential of deep learning constrained reconstruction in enhancing the quality and efficiency of DWI. This approach offers a promising clinical implementation to obtain high-quality DWI images while reducing scan time.
Fast susceptibility distortion correction for diffusion MRI using style transfer and nonrigid registration
Authors: Chigurupati Sreekar , Schilling Kurt , Warfield Simon , Garyfallidis Eleftherios
Published: November 2024

Motivation: Diffusion MR images suffer from susceptibility distortion artifacts due to field inhomogenities and susceptibility changes at tissue interfaces. This results in a spatial mismatch of the MR signal. Current methods either use blip-up, blip-down acquisitions and/or are compute-intensive. Goal(s): Our goal is to develop a fast registration-based susceptibility distortion correction method without the need to acquire an opposite phase-encode scan. Approach: We use synthesized b0 volumes generated using synb0 as a registration target for SyN registration to correct susceptibility distortion. Results: Our distortion correction method produces results that are qualitatively and quantitatively similar to state-of-the-art methods in a fraction of the time. Impact: Our approach serves as a good starting point to explore registration based distortion correction methods. Faster correction methods will enable widespread use of dMRI in the clinical setting where accurate shape is needed for critical decisions like treatment planning.
Pushing the boundaries of in-vivo human diffusion MRI using Romer-EPTI: initial results on the Connectome 2.0 scanner
Authors: Dong Zijing , Reese Timothy , Lee Hong-Hsi , Ma Yixin , Llordén Gabriel , Park Daniel , Mahmutovic Mirsad , Keil Boris , Rosen Bruce , Polimeni Jonathan , Huang Susie , Wald Lawrence , Wang Fuyixue
Published: November 2024

Motivation: The progress in in-vivo high-resolution and high-b-value dMRI has advanced the investigation of structural connectivity and tissue microstructure. Goal(s): We aim to further push the spatial resolution and b-value of in-vivo diffusion MRI. Approach: A high-SNR(√25x), distortion-free, motion-robust Romer-EPTI technique that addresses the challenges in dMRI acquisition with further enhanced capabilities by taking advantage of the cutting-edge Connectome 2.0 scanner. Results: We demonstrate motion-robust distortion-free in-vivo mesoscale dMRI (~485um-istropic) on clinical 3T&7T scanners, and further improvements in SNR on Connectome2.0 scanner enabling high-SNR, high b-value dMRI and a spatial resolution up to 400um-iso. Impact: Romer-EPTI achieves high-SNR motion-robust distortion-free in-vivo mesoscale dMRI (~485 um) with exceptional quality on clinical 3T&7T scanners. Its capabilities were further enhanced on the Connectome 2.0 scanner, enabling high-SNR high b-value dMRI and a spatial resolution up to 400um-iso.
Improved fat suppression of TSE-DWI in the head-neck using enhanced slice-selective gradient reversal (enhanced LIPO)
Authors: Murayama Daichi , Yoneyama Masami , Sakai Takayuki , Ball Iain , Ochi Shigehiro
Published: November 2024

Motivation: TSE-DWI provides distortion-free images, but it has a disadvantage in terms of its low signal-to-noise ratio (SNR). TSE-DWI basically requires several signal averages to obtain sufficient SNR, resulting in long scan time. Goal(s): We modified and optimized the LIPO selective gradients (enhanced LIPO) to maximize the fat suppression effect for TSE-DWI in the neck, and compared with conventional methods (SPAIR TSE-DWI and LION TSE-DWI) to investigate its clinical usefulness. Approach: SNR and CR were calculated with ROIs placed in parotid gland and fat around neck. Results: Combining TSE-DWI with enhanced LION improves the robustness of fat suppression while maintaining better SNR. Impact: The present findings suggest that both conventional and enhanced LION TSE-DWI showed improved SNR because it does not require fat suppression pre-pulse. Furthermore, enhanced LION further improved the robustness of fat suppression.
Submillimeter Isotropic Whole Brain DTI at 3T with 2D Multi-band Multi-shot EPI Acquisition and Deep Learning Reconstruction
Authors: Yang Baolian , Wang Xinzeng , Petty Christopher , Guidon Arnaud , Lebel R. Marc , Banerjee Suchandrima , Song Allen
Published: November 2024

Motivation: High resolution diffusion tensor imaging (DTI) is associated with low intrinsic sensitivity and therefore it is difficult to achieve simultaneously high resolution and high SNR. Goal(s): To acquire submillimeter DTI to map human brain structural connectivity networks with improved accuracy and detail than standard resolution DTI. Approach: We combine a deep learning reconstruction method with MB-MUSE to further enhance the image quality and demonstrate improved quantification of submillimeter isotropic (0.8×0.8×0.8 mm3) whole brain DTI at 3T with approximately 1 minute per diffusion direction scan time. Results: The exceptional delineation and clarity of fiber tracking was achieved from submillimeter isotropic whole brain DTI. Impact: Submillimeter isotropic whole brain DTI with approximately 1 minute per diffusion direction scan time at 3T with high SNR, low distortion, provides us with a powerful tool to map whole brain structural connectivity networks with exceptional clarity and quantification.
3D Diffusion Image Acquisition with Motion Offsetting and
Navigation-Dependent Segmentation (DIAMONDS)
Authors: Johansson Jens , Lagerstrand Kerstin , Hebelka Hanna , Maier Stephan
Published: November 2024

Motivation: Investigate whether 1D navigator echo phase information can be used to correct residual phase errors in single thick-slab segmented 3D-DWI with first and second order motion-compensated diffusion encoding gradients. Goal(s): Perform high-resolution single thick-slab segmented 3D-DWI with full brain coverage. Approach: Extend a first and second order motion-compensated segmented 3D-DWI sequence with three orthogonal 1D navigators, which are utilized to correct for residual phase errors. Results: Correction of zeroth order phase shifts, which result from translation, demonstrated reduction of ghosting artifacts. First order phase terms, which arise from rotation, were also determined, but require a more complex correction strategy. Impact: Motion-compensated single thick-slab segmented 3D-DWI with orthogonal 1D navigators is a completely novel and promising approach for high resolution diffusion imaging with full brain coverage.
3D diffusion MRI at 7T with Universal Pulses for improved image uniformity
Authors: Feizollah Sajjad , Löwen Daniel , Couch Marcus , Pracht Eberhard , Stöcker Tony , Tardif Christine
Published: November 2024

Motivation: 2D multi-slice diffusion-weighted MRI (dMRI) suffers from severe signal non-uniformity caused by B1+ inhomogeneity at ultra-high fields. Goal(s): To design a 3D dMRI sequence with Universal parallel transmission radio-frequency Pulses (UPs) to improve image uniformity across the brain at 7T without lengthening workflow. Approach: We propose a 3D spin-echo sequence with an inversion pulse before excitation to enhance SNR. 3D UPs were designed for inversion, excitation, and refocussing and implemented in a sequence with a stack-of-EPI readout. Results: Diffusion-weighted image uniformity was significantly improved using the 3D sequence with UPs in comparison to 2D dMRI at 7T. Impact: We propose a 3D dMRI sequence that includes UPs to improve image uniformity across the brain at 7T, including the temporal lobes and cerebellum. This improvement in image quality is critical for precision mapping of whole brain structural connectivity.
Acceleration of Diffusion-Relaxation Multidimensional MRI acquisition exploiting Locally low-rank with Block Adaptive Regularization
Authors: Park Joon Sik , Benjamini Dan
Published: November 2024

Motivation: Multidimensional (MD)-MRI provides valuable sub-voxel information. However, it suffers from prohibitively long acquisition time making it impractical for routine clinical use. Goal(s): To reduce MD-MRI scan time via partial k-space sampling in conjunction with a novel reconstruction framework. Approach: Achieve data reduction by using random incoherent sampling, followed by locally low-rank reconstruction with block adaptive regularization, and comparison with ground-truth. Results: In-vivo performance of MD-MRI image reconstruction method that achieves R=4 reduction factor was demonstrated. This framework provides whole-brain coverage with 2mm$$$^3$$$ voxels in 20 minutes, while maintaining robustness and accuracy. This innovation has significant potential for clinical neurological applications. Impact: Multidimensional MRI is crucial for investigating tissue microstructure, brain connectivity, and pathology in clinical study. Here we present a novel image reconstruction framework that allows R=4 k-space data reduction factor, providing whole-brain coverage with 2mm$$$^3$$$ voxels MD-MRI data in 20minutes.
Fast Multipole Method-Enhanced Boundary Element Modeling for Total Field Inversion in Quantitative Susceptibility Mapping
Authors: Zhong Haodong , Wang Yi , Nguyen Thanh D. , Song Yang , Li Jianqi
Published: November 2024

Motivation: The study aims to improve quantitative susceptibility mapping (QSM) precision at region of interest (ROI) boundaries where background field interference affects accuracy. Goal(s): To introduce a novel boundary element method total field inversion (BEM-TFI) enhanced by the fast multipole method (FMM) for high-resolution QSM. Approach: A comparative assessment of BEM-TFI technique was performed with traditional QSM methods, utilizing in-vivo data and simulated field maps to determine inversion quality and background field removal efficiency. Results: Enhanced by FMM, the BEM-TFI method demonstrated significant improvements in accurately discerning tissue susceptibility from background noise, indicating a substantial advancement in the outcomes of QSM. Impact: The BEM-TFI enhancement in QSM accuracy allows for more detailed characterization of the brain's cortex, potentially enriching neuroscientific research and elevating the quality of neuroimaging data.
Effect of cortical orientation relative to the magnetic field on quantitative susceptibility mapping in the grey matter
Authors: Liu Jiaen , Huang Yujia
Published: November 2024

Motivation: Effect of cortex orientation relative to the magnetic field can impede quantitative susceptibility mapping (QSM) from being established as a robust measurement of cortical pathology. Goal(s): To identify the significance of cortical orientation effect in QSM and its underlying contribution from cortical myelin. Approach: QSM was performed in eight healthy subjects at isotropic 0.75mm resolution at 3T. The relationship between QSM and cortical orientation was evaluated in cortical regions across the brain. The region-specific effect strength was correlated with region-average myelin approximation. Results: Significant orientation effect was observed in most brain regions, including significant correlation between the region-specific effect strength and myelin estimation. Impact: This study represents an initial effort to uncover the cortex orientation effect in cortical grey matter QSM result towards establishing QSM as a robust clinical tool for cortical pathology.
Physics-informed vessel segmentation for χ-separation (chi-separation)
Authors: Kim Taechang , Ji Sooyeon , Min Kyeongseon , Youn Jonghyo , Kim Minjun , Kim Jiye , Lee Jongho
Published: November 2024

Motivation: χ-separation is an advanced QSM method that provides para- and diamagnetic susceptibility maps. Despite its potential utilities, both maps reveal (erroneously) high intensity signals from vessels, hampering their applications and quantification. Goal(s): Proposing a vessel segmentation method designed for χ-separation by utilizing physical properties of vessel signals in χ-separation. Approach: Acquiring seeds by informing physics of vessels in χ-separation, and vessel geometry characteristics guided-region growing is implemented to generate vessel masks. Results: Our method successfully creates vessel masks for both susceptibility maps and demonstrates to be robust to various input types. When applied to an ROI analysis, reduced variability in measurements was shown. Impact: The novel vessel segmentation method utilizes physical properties of vessels in χ-separation for reliable and robust segmentation, providing substantially improved segmentation results. It may help us to improve downstream analysis when quantifying susceptibility of myelin or tissue iron excluding vessels.
In-vivo high-resolution χ-separation (chi-separation) at 7T
Authors: Kim Jiye , Shin Hyeong-Geol , Kim Minjun , Ji Sooyeon , Min Kyeongseon , Jeong Hwihun , Kim Seong-Gi , Lee Jongho
Published: November 2024

Motivation: High-resolution χ-separation at 7T can delineate detailed structures related to iron and myelin concentrations in the brain. However, it has the challenge of requiring an R2 map, which is not practical at 7T due to SAR and scan time. Goal(s): Our objective is to generate high-resolution χ-separation maps at 7T. Approach: An R2* 7T-to-3T conversion network to transform a 7T R2* map into its 3T counterpart is developed. Then, 𝜒-separation is processed via QSMnet, χ-sepnet-R2*, and resolution generalization. Results: We successfully produced high-quality and high-resolution 𝜒-separation maps only from multi-echo gradient echo data at 7T. Impact: This study suggests a solution for the technical challenge of requiring R2 map in 7T χ-separation, enabling high-resolution (=650 um) χ-separation. This may benefit the analysis of iron and myelin concentration changes in various neurodegenerative diseases through detailed structural examination.
Optimized 7-Tesla QSM reconstruction: Clinical feasibility
Authors: Ma Felisha , Ozbay Pinar , Balchandani Priti , Alipour Akbar
Published: November 2024

Motivation: Quantitative Susceptibility Mapping (QSM) at 7-Tesla (7T) has been implicated to improve assessment of neurodegenerative disorders but has yet to be integrated into clinical practice. Goal(s): We aimed to address the growing demand for a standardized and optimized QSM reconstruction protocol that enables accurate quantification of susceptibility, mitigates contaminating artifacts, and is clinically feasible. Approach: Here, we compared 32 end-to-end QSM processing pipelines and evaluated their performance. Results: We show that reconstruction with Laplacian phase-unwrapping, RESHARP background field removal, and MEDI dipole inversion outperformed other pipelines in suppressing artifacts. Impact: Our optimized pipeline results in a 7T QSM reconstruction with clear cortical and subcortical boundaries, and mitigates susceptibility artifacts. Furthermore, the comprehensive review of QSM processing algorithms highlights Laplacian, RESHARP, and MEDI as robust algorithms with reliable, consistent performance.
How far away from anisotropic microstructure do you need to be for QSM to be faithful?
Authors: Sandgaard Anders , Jespersen Sune
Published: November 2024

Motivation: White matter (WM) microstructure can affect estimation of WM susceptibility with QSM. However, as QSM fits all voxels at once, it is less understood how it affects estimation of surrounding tissue. Goal(s): Our goal is to demonstrate the effect of a cylindrical microstructure on surrounding tissue in a digital phantom. Approach: We synthesize a digital phantom with parallel rods surrounded by a rim with random dots. We estimate susceptibility with (QSM+) and without (QSM) account of microstructure. Results: QSM is biased inside the rim, and this error spreads to the surrounding tissue characterized by a power law. QSM+ improved susceptibility fitting. Impact: It may be important to account for microstructure in WM even though one may only be interested in analyzing surrounding tissue like gray matter. Failing to do so could lead to misinterpretation of tissue magnetic susceptibility.
Explained variance of cerebrospinal fluid component in resting-state fMRI as a potential biomarker for proportionate perivascular space volume
Authors: Kang Daehun , Lapid Maria , Welker Kirk , Min Paul , In Myung-Ho , Bernstein Matt , Shu Yunhong
Published: November 2024

Motivation: Estimating cerebrospinal fluid (CSF) in perivascular spaces (PVS) is essential to advance understanding of glymphatic clearance of cerebral waste products. Goal(s): This study aimed to explore a novel method for evaluating CSF in PVS in awake subjects, including healthy controls and those with mild cognitive impairment (MCI). Approach: We analyzed the explained variance of CSF components (CSF-derived R2) in resting-state fMRI images to determine the proportionate volume of PVS. Results: We observed a decline in CSF-derived R2 with aging in healthy controls. Conversely, elevated CSF-derived R2 in MCI participants suggests enlargement of PVS, which may implicate altered glymphatic function in cognitive disorders. Impact: The CSF-derived R2 metric from resting-state fMRI images offers a quantifiable assessment of CSF volume in perivascular spaces of the gray matter, holding potential as a biomarker for investigating glymphatic system efficiency.