bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward Densely Populated Dipole Arrays for Human Prostate Imaging at 7T: 8Tx16Rx Coaxial-End Dipole Array
Authors: Solomakha Georgiy , May Markus , Kraff Oliver , Scheffler Klaus , Quick Harald , Avdievich Nikolai
Published: November 2024

Motivation: To improve SNR and the SAR-performance in prostate imaging at 7T using a densely populated coaxial-end dipole array. Goal(s): To numerically optimize and evaluate an 8Tx/16Rx coaxial-end dipole array for prostate imaging at 7T. Approach: Geometry of a coaxial-end element was optimized to minimize peak SAR and improve coverage. In transmission, 16 coaxial-end dipoles were combined into 8 pairs. This further reduced pSAR. 8-element fractionated dipole and stripline arrays were simulated for comparison. Results: Optimized 8Tx/16Rx coaxial-end dipole array improved SNR in prostate compared to all other 8-element arrays. SAR-performance of the developed array was better than that of other dipole arrays. Impact: We demonstrated that densely populated 16-element coaxial-end dipole array improved SNR in the prostate by at least 10% compared to 8-element arrays. In addition, combining 16 elements in 8 pairs during transmission improved SAR-performance in comparison to the 8-channel array.
Non-idealized system (NIS) optimization of EPI sequences at ultra-high field.
Authors: West Daniel , Glang Felix , Endres Jonathan , Leitão David , McElroy Sarah , Zaiss Moritz , Hajnal Jo , Malik Shaihan
Published: November 2024

Motivation: MRI scanners are built under the assumption of near perfect responses of each subsystem. Computing advances mean that this may no longer be necessary, enabling exploration of cheaper, efficient alternatives. Goal(s): To allow high-performance scanning with less emphasis on hardware performance, reducing costs and improving access. Approach: We consider non-idealized system optimization where hardware imperfections are built into a forward model used to optimize pulse sequences via the MR-zero framework. We experimentally demonstrate NIS using measured GIRFs from a 7T system to optimize EPI sequences. Results: NIS optimization produces sequences that substantially reduce image artefacts even for scenarios that previously exceeded hardware constraints. Impact: NIS optimization embraces gradient system imperfections, discovering novel acquisition strategies to inherently mitigate them. Although demonstrated on a state-of-the-art 7T scanner, the concept of including imperfections directly into sequence design offers a means to maximize performance of any scanner hardware.
Towards Reproducible Intravoxel Incoherent Motion (IVIM) Analysis: The ISMRM Open Science Initiative for Perfusion Imaging
Authors: Jalnefjord Oscar , Rashid Ivan , Kuppens Daan , van der Thiel Merel , van Houdt Petra , Voorter Paulien , Peterson Eric , Gurney-Champion Oliver
Published: November 2024

Motivation: Lack of validated and open-source intravoxel incoherent motion (IVIM) post-processing and fitting code is hindering reproducible research, limiting the validation and large-scale roll-out of IVIM imaging. Goal(s): To create an open-source code repository for IVIM-related code. Approach: Scientists interested in IVIM are encouraged to upload their code to our open-source code repository built by the ISMRM OSIPI task force 2.4, where automated testing and evaluation based on reference data are used to enable quality control of the code. Results: As of November 2023, 19 code contributions have been submitted by 6 different institutes, all passing automated testing. Impact: The work of ISMRM OSIPI task force 2.4 enables an open-source platform for validated code relevant to intravoxel incoherent motion (IVIM) imaging, thus reducing duplicate development, improving reproducibility, and serving as a benchmark for future methods.
How frequently should we use a phantom for QA? A preliminary assessment
Authors: Jordanova Kalina , Ogier Stephen , Russek Stephen , Stoffer Cassandra , Buonincontri Guido , Nittka Mathias , Keenan Kathryn
Published: November 2024

Motivation: Currently, we do not know how frequently quality assurance (QA) should be performed on an MRI scanner to detect changes that impact quantitative measurements. Goal(s): Our goal is to determine the frequency of QA measurements needed during the course of a quantitative in vivo study to have confidence in the in vivo measurements. Approach: Phantom quantitative QA measurements were made immediately before or after the in vivo measurements over the duration of a repeatability study. Results: All quantitative phantom measurements had variation well below 10 % over the course of the 99 day study. Impact: We now know that for measurements using magnetic resonance fingerprinting on this system, QA using phantom measurements is only necessary at the start and end of an in vivo study when the study duration is less than approximately 3 months.
Simultaneous acquisition of MR elastography, Dixon and X-ray CT like image
Authors: Numano Tomokazu , Ito Daiki , Takamoto Koichi , Kamio Hiroyo , Tanabe Nobuaki , Konuma Shota , Ishihara Yoshito , Kikuchi Jo , Oka Hiromu , Nishijo Hisao
Published: November 2024

Motivation: The purpose of study was integration of Dixon and X-ray CT like image technique in the GRE-MultiEcho-MRE sequence. Goal(s): The additional visualization of bone damage and water / fat compornents on MR elastography would yield benefits in evaluating radiologic skeletal muscle evaluation, since soft tissue injuries can be assessed directly related to the osseous injuries using one image modality. Approach: The effectiveness of this method was evaluated by volunteer studies using the original MRE pulse sequence and vibration system. Results: This method allows simultaneous acquisition of elastograms, wave images, water/fat component images and X-ray CT like images. Impact: For the patient, a reduction in total imaging time is beneficial. For the clinicians, images such as elastograms, wave images, water/fat component images, and X-ray CT are available simultaneously for multimodal diagnosis.
Nonlinear storage modulus quantification with MR-elastography: from in vitro to in vivo assessment
Authors: Pagé Gwenaël , Gennisson Jean-Luc , Garteiser Philippe , Van Beers Bernard
Published: November 2024

Motivation: Estimating the nonlinear coefficient in MR elastography could provide a relevant mechanical parameter for tumor characterization. Goal(s): The goal of this study was to develop a method for assessing the nonlinear coefficient in MR elastography. Approach: We developed a specific MR elastography setup and a post-processing pipeline to quantify nonlinear coefficients in phantoms and mice with a tumor implanted subcutaneously. Results: In phantoms, we observed that nonlinear coefficient was able to provide a higher contrast than storage modulus to distinguish different structure. In addition, in mice, nonlinear coefficient was correlated to the entropy which is a marker of collagen distribution irregularity. Impact: The estimation of the nonlinear coefficient provides a new biomarker to assess tissue mechanical parameters. The relation between this parameter and tissue structure could be relevant in tumor investigation, as tissue microarchitecture is an important marker of tumor severity.
Initial Feasibility of Free-breathing Multiparametric Mapping with Echo Planar Imaging to Derive T1, T2 and ADC Maps
Authors: Mai Dingheng , Kara Danielle , Liu Yuchi , Kwon Deborah , Nguyen Christopher
Published: November 2024

Motivation: Co-registered quantification of relevant tissue characteristics including T1, T2 and ADC has the potential to aid the diagnosis of various cardiomyopathies. Goal(s): Our goal was to produce co-registered cardiac T1, T2 and ADC maps using free-breathing MultiParametric single shot Echo Planer Imaging (MP-EPI). Approach: Pixel-wise value quantifications of T1, T2, and ADC were calculated and compared in a static phantom and 5 healthy subjects following respiratory motion correction. Results: The MP-EPI technique demonstrated consistency with reference measurements (R>0.97) for T1 and T2 values, with no significant differences observed in human subjects (p>0.2), and normal ADC values. Impact: Free breathing, co-registered multiparametric maps from EPI-based images may provide complementary information for the diagnosis and characterization of comprehensive myocardiopathies. This method has the potential to expand to include other tissue characterization in the heart, such as T2*, and CEST.
A MULTIPLEX-Lite method for fast 3D multi-parametric imaging with MR Angiography
Authors: Ye Yongquan , Li Miaowen , Li Hongyu , Wu Ying , Xu Jian
Published: November 2024

Motivation: Existing 3D multi-parametric imaging methods suffers from long scan times, and decent MRA contrasts are yet to be provided. Goal(s): To develop a 3-minute 3D high resolution multi-parametric imaging method that offeres whole brain imaging with TOF quality MRA results. Approach: A simplified version of the MULTIPLEX method, namely MULTIPLEX-Lite, is proposed. Compared to the original MULTIPLEX method, addtional MRA results are offered, while removing the T1 and PD mappings to further improve scan time. Results: The proposed MULTIPLEX-Lite method offered whole brain high resolution (<1mm3 voxel volume) MRA, PDW, T1W, aT1W, SWI, R2* maps and QSM in one 3-minute scan. Impact: The proposed MULTIPLEX-Lite method is among the most feasible and practical solutions for routine clinically friendly 3D high-resolution multi-parametric imaging practices.
Validation of in vivo VERDICT fIC against matched histology from whole-mount prostatectomy
Authors: Munoz Marta Masramon , Mathew Manju , Singh Saurabh , Mertzanidou Thomy , Suman Shipra , Clemente Joey , Retter Adam , Papoutsaki Marianthi-Vasilik , Smith Lorna , Grussu Francesco , Kasivisvanathan Veeru , Grey Alistair , Dineen Eoin , Shaw Greg , Carter Martyn , Patel Dominic , Caselton Lucy , Moore Caroline M. , Atkinson David , Haider Aiman , Freeman Alex , Alexander Daniel , Punwani Shonit , Panagiotaki Eleftheria
Published: November 2024

Motivation: Intracellular volume fraction (fIC) maps from VERDICT-MRI have shown potential to improve prostate cancer (PCa) stratification, but the microstructural origin of the signal has not yet been investigated in in vivo settings. Goal(s): Investigate the accuracy of fIC from in vivo VERDICT-MRI as a measurement of cell density using matched prostatectomy specimens. Approach: Using personalised moulds from multiparametric (mp)MRI and deep learning image registration, we align whole prostatectomy histology images with corresponding VERDICT MR images. We compare fIC maps against cell density maps derived from histology. Results: fIC maps show very strong agreement with histology-derived cell density maps of epithelial cells (r=0.8303). Impact: Our study shows that VERDICT fIC maps are accurate descriptors of epithelial cell density in the prostate. The biological interpretability of these maps will facilitate translation into clinical practice, improving PCa stratification from MRI.
Spatial Imaging Transcriptomic reveals the molecular basis among diffusion MRM models
Authors: Shen Yiqi , Shen Yao , Cao Zuozhen , Li Sihui , Xu Guojun , Zhao Zhiyong , Dan Wu
Published: November 2024

Motivation: Integration of MRI and spatial transcriptomics may provide a new approach for imaging-genetics research for probing molecular basis underlying observed MRI phenotypes. Goal(s): We proposed a pipeline for integration of diffusion MRI(dMRI) and spatial transcriptomics of mouse brain to understand potential biological pathway underlying dMRI microstructural models. Approach: We spatially co-register population-averaged dMRI maps of mouse brain to 2D spatial transcriptomic for pixelwise correlation and explored genes function and celltype related with dMRI metrics. Results: We found FA was associated with myelination and oligodendrocyte and water diffusivity was associated with neurons. We identified molecular basis driving two distinct gradients of dMRI in cortex. Impact: Integration of spatial transcriptomics and MRI enables imaging-genomics analysis at an unprecedented resolution. Our study revealed molecular basis for typical microstructural markers in diffusion MRI. We further revealed genetic driven force of cortical gradients in axial and radial diffusivity maps.
Tensor-Valued Diffusion MRI Identifies Brain Microstructural Alterations in Gene Knockdown Mouse
Authors: Yuan Jianyu , Liu Yuxuan , Li Shuai , Liang Mingyao , He Yi , He Huanhuan , Shan Hong
Published: November 2024

Motivation: DEAD‐box helicase 24 (DDX24) gene mutations linked to abnormalities of major vessels1. However, the effect of the gene DDX24 on brain microstructure remains unclear. Goal(s): Our goal was to demonstrate how advanced tensor-valued diffusion MRI can reveal microstructural alterations in a Ddx24 knockdown mouse model. Approach: We performed advanced tensor-valued diffusion MRI to examine Ddx24 knockdown mouse brain and evaluated the performance of Ddx24 knockdown mice in the Morris water maze test. Results: Ddx24 knockdown mouse revealed declining microscopic anisotropy kurtosis (MKA) in corpus callosum and hippocampus. Tensor-valued diffusion MRI is a sensitive neuroimaging tool to evaluate gene-edited mouse brain microstructural alterations. Impact: Advanced tensor-valued diffusion MRI provided cylinders shapes sensitive MKA and spherical shapes sensitive MKI for detecting microstructural alterations in genetic diseases.
Snap, Crackle And Pop: Benefits of Serial Motion Compensation in Cardiac Diffusion Tensor Imaging
Authors: Coveney Sam , Afzali Maryam , Foster Richard J. , Müller Lars , Sharrack Noor , Yuldasheva Nadira Y. , Plein Sven , Szczepankiewicz Filip , Dall'Armellina Erica , Schneider Jürgen E. , Teh Irvin
Published: November 2024

Motivation: Cardiac diffusion tensor imaging (cDTI) based on spin-echo employs up to 2nd order (M2) motion compensated diffusion gradients. It is unclear whether higher order motion compensation would be beneficial. Goal(s): To evaluate the impact of higher order motion compensation (i.e. velocity, acceleration, jerk, snap, crackle and pop) in cDTI. Approach: Diffusion gradient waveforms with M1 to M6 motion compensation were designed and implemented in a prospective study of healthy volunteers. Mean diffusivity and fractional anisotropy maps were quantitatively evaluated. Results: Significant reductions in MD and MD heterogeneity were observed in the M6 relative to M2 compensated data. Impact: We demonstrate the potential importance of compensating for higher orders of motion (>M2) in cardiac diffusion MRI. This work may inform gradient waveform design for more accurate and robust cardiac diffusion MRI.
A deep learning framework for assessing remodelling and functional changes in infarcted left ventricles with reduced ejection fraction
Authors: Buoso Stefano , von Spiczak Jochen , Schlenker Rabea , Manka Robert , Kozerke Sebastian
Published: November 2024

Motivation: To perform a retrospective analysis of the anatomical and functional remodelling of left ventricles 4 and 12 months after the ischemic event. Goal(s): To assess differences in remodelling between patients with recovered function and those without. Approach: A deep-learning framework was developed to fit a statistical shape model to all cardiac phases of each patient and compute strains, valve motion and morphological descriptors. Results: Peak strain values and valve displacements at 4 and 12 months show different trends between patients with recovered function and those without. Peak-systolic shapes of patients with positive remodelling show a lower sphericity with respect to the others. Impact: A deep learning framework reveals that relative changes in peak systolic anatomical shapes, radial and circumferential strains and valve motion after 4 months could provide a discriminator for predicting positive remodelling and restoration of functionality in patient with heart failure.
Quantitative UTE Imaging of Zonal Difference in Meniscus
Authors: Suprana Arya , Silva Melissa Lou , Toto-Brocchi Marco , Malhi Bhavsimran , Athertya Jiyo , Lo James , Shin Soo Hyun , Le Nicole , Chang Eric , Du Jiang , Ma Yajun
Published: November 2024

Motivation: Quantitative MR imaging techniques could reveal compositional differences between red and white zones in menisci. Unfortunately, this type of analysis may not be possible using conventional sequences due to the rapid signal decay of menisci. Goal(s): The study aimed to investigate whether quantitative UTE imaging techniques could detect the zonal difference between the red and white zones in menisci. Approach: UTE imaging techniques, including UTE-T1, UTE-MT modeling, UTE-AdiabT1ρ, and UTE-T2*, were used to assess menisci in vivo quantitatively. Results: T1, MMF, and T2* values in the red zone are significantly lower than those in the white zone. Impact: Our qUTE MRI techniques enable a quantitative, zonal, and compositional analysis of menisci in vivo, which is valuable in helping understand the role of menisci in the pathogenesis of complex diseases such as osteoarthritis.
Modelling the intermediate flow regime in flow-compensated intravoxel incoherent motion MRI
Authors: Rosenqvist Louise , Ljungberg Maria , Jalnefjord Oscar
Published: November 2024

Motivation: Lack of consensus in perfusion modelling in IVIM MRI, with focus on blood flow in biological tissue. Goal(s): To model perfusion in flow-compensated IVIM MRI to allow for blood velocity and correlation time quantification. Approach: Using a velocity autocorrelation function to describe the dynamics of capillary blood flow, an expression for perfusion signal attenuation was derived for flow-compensated IVIM MRI, and evaluated in healthy brain. Results: The proposed model allows for direct quantification of velocity and correlation time of blood flow, in addition to perfusion fraction and diffusion coefficient. Impact: The study presents initial proof-of-concept directly quantifying velocity and correlation time of blood flow in healthy brain using flow-compensated Intravoxel Incoherent Motion MRI. Access to these parameters can assist in characterizing tissue microvasculature in disease.
Relationships between Brain Microstructures and Visual Field Loss Patterns in Glaucoma using Diffusion MRI and Archetypal Analysis
Authors: Pang Yueyin , Parra Carlos , Bang Ji Won , Fieremans Els , Wollstein Gadi , Schuman Joel , Wang Mengyu , Chan Kevin
Published: November 2024

Motivation: In bilateral glaucoma, visual field loss often spares complementary regions between eyes to optimize residual vision, but the underlying mechanisms are unknown. Goal(s): Investigate how brain microstructural environment relates to regional visual field loss patterns in glaucoma. Approach: Advanced diffusion MRI parameters of optic radiation integrity were correlated with glaucomatous visual field loss patterns using partial correlation and archetypal analyses. Results: Diffusion MRI metrics generally correlated with overall visual field loss. Complementary archetypal loss patterns were also found between eyes when associating pointwise visual field to certain MRI metrics sensitive to axonal/glial integrity and neuroinflammation, suggesting their involvement in influencing residual binocular vision. Impact: Advanced neuroimaging combined with computational analysis can provide insights into the brain’s role in influencing preferential damage to maximize retained binocular vision in glaucoma. Diffusion MRI holds promise for assessing glaucoma progression and brain plasticity for guiding vision preservation.
Brain CSF clearance measured by phase-contrast MRI and dynamic 18F-MK-6240 PET in Alzheimer's disease
Authors: Zhou Liangdong , Chiang Gloria , Wang Xiuyuan , Liu Pan , Kovanlikaya Ilhami , Baledent Olivier , de Leon Mony , Li Yi
Published: November 2024

Motivation: Beta-amyloid (Aβ) in Alzheimer’s disease (AD) is caused by decreased glymphatic clearance function. As the main source of CSF in glymphatic system, the mechanism of CSF dynamic in ventricle system is of great importance. Goal(s): Use dynamic 18F-MK-6240 PET and PC-MRI to study the relationship of CSF clearance in lateral ventricle (LV) and aqueduct. Approach: CSF turnover rate in LV is derived from dynamic 18F-MK-6240 PET. Aqueduct parameters were calculated using PC-MRI data. Linear regression analysis was performed between PET and PC-MRI measurements. Results: The CSF clearance measurements from both PET and MRI are consistent and show diagnostic group difference. Impact: 18F-MK-6240 PET derived CSF turnover rate and phase-contrast MRI produced aqueduct CSF measurements are highly correlated. The data reveals diagnostic group difference after controlling for age and sex, indicating that the decreased CSF clearance is associated with Alzheimer’s disease.
Non-invasive quantification of myocardial volume oxygen consumption using free-breathing, ungated, self-calibrated MR blood oximetry
Authors: Yang Chia-Chi , Malagi Archana , Huang Yuheng , Yoosefian Ghazal , Zhang Xinheng , Guan Xinming , Christodoulou Anthony , Li Debiao , Han Hui , Dharmakumar Rohan , Yang Hsin-Jung
Published: November 2024

Motivation: Whole-heart myocardial oxygen consumption (MVO2) is the central factor that determines cardiac function and is a sign of heart diseases. Goal(s): We proposed a high-resolution, free breathing, cardiac-phase resolved sequence to quantify MVO2 in the beating hearts. Approach: Healthy pigs were scanned at 3T. Coronary sinus images were acquired with a continuous, free-breathing, Radial T2Prep-IR sequence with flow compensation and water excitation and a 2D phase contrast sequence to quantify the MVO2. Invasive ground truth was also measured to verify the accuracy of our estimation. Results: The proposed method measured comparable SbO2,OEF,MBF and MVO2 values to the invasive ground truth. Impact: The proposed free-breathing, motion-resolved cardiac MR Oximetry technique has the potential to non-invasively measure accurate myocardial oxygen consumption without using ionizing radiation and exogenous contrast agents.
MRI with cancer cell membrane coated Mn (II) nanoprobes in precise diagnosis of early pancreatic cancer
Authors: Zhong Yanqi , Hu Shudong , Dou Weiqiang
Published: November 2024

Motivation: gadolinium widely used in MRI clincally show low detecting efficiency for early pancreatic cancer(<2 cm). It is thus urgent to develop safe and effective contrast agents to address this issue. Goal(s): This study aims to investigate the potential of cancer cell membrane coated Mn(II) nanoprobes (PMNP@CMs) in MRI for precise diagnosis of early pancreatic cancer. Approach: PMNP@CMs were prepared for MRI of pancreatic cancer to explore the imaging effects in vivo and in vitro compared with gadolinium. Results: PMNP@CMs showed more predominant MRI effect than gadolinium and may be considered as safe and efficient contrast agents to realize diagnosis for early pancreatic cancer. Impact: This work has developed a nano magnetic resonance imaging contrast agent (PMNP@CMs) that is more advantageous than gadolinium and can achieve precise diagnosis of early pancreatic cancer.
Assessment of rhabdomyolysis-induced acute kidney injury with chemical exchange saturation transfer MRI
Authors: Zhang Qianqian , Tao Quan , Chen Zelong , Seeliger Erdmann , Deng Kan , Wu Zhigang , Niendorf Thoralf , Feng Yanqiu
Published: November 2024

Motivation: There is a gap in exploring the progression of acute kidney injury (AKI) caused by rhabdomyolysis (RM). Goal(s): Investigate the feasibility of CEST MRI for assessing the progression of RM-induced AKI in a mouse model. Approach: The RM-AKI model was established by intramuscular injection of glycerol solution and examined longitudinally by CEST (days 1, 3, 7, 15, 30). CEST quantification parameters and their diagnostic performance were compared. Results: MTR presented a significant difference, and showed the best diagnostic performance for AKI and moderate negative correlations with pathological changes. Impact: MTR has potential clinical utility for assessing renal diseases.
23Na Magnetic Resonance Imaging in Sepsis-Induced Acute Kidney Injury: A Preclinical Study
Authors: Nahardani Ali , Moradi Sara , Vo Van Nhat Minh , Hoerr Verena
Published: November 2024

Motivation: Currently, there is a lack of research in 23Na-MRI, investigating the renal sodium concentration gradient in Sepsis-Induced acute kidney injury (AKI). Goal(s): This study aimed to investigate sodium concentration changes across the renal parenchyma and to compare them with T1, T2, and T2* alterations as well as kidney perfusion. Approach: 38 mice (N=19 as control and N=19 with septic AKI) were investigated by multi-parametric MRI. Results: In septic AKI, thrombi developed in kidneys and caused renal hypoperfusion. Lack of blood supply to kidneys resulted in sodium retention at cortex and little sodium output at pelvis even in the absence of detectable edema. Impact: This study helps to better understand the radiological pathology of sepsis-induced acute kidney injury in 23Na-MRI. It connects the concept of altered sodium concentration with changes in renal perfusion, T1, T2, and T2* relaxation constants.
Synthesized Gd-EOB-DTPA-enhanced hepatobiliary phase MR images via generative adversarial learning
Authors: Zhao Kaixuan , Liu Yan , Wu Zhigang , Xu Yongzhou , Liu Zaiyi , Wang Guangyi
Published: November 2024

Motivation: Gd-EOB-DTPA-enhanced hepatobiliary phase (HBP) imaging is clinical routine for liver lesion identification, and is usually empirically conducted at 20 minutes after bolus injection. Goal(s): Our goal was to demonstrate the feasibility of optimizing clinical workflow by synthesizing Gd-EOB-DTPA-enhanced HBP images via machine learning. Approach: Precontrast and early-enhanced T1WIs (5-min after bolus injection) acquired at 3 T were used to synthesize HBP images via a generative adversarial network in 490 subjects. Results: Our preliminary results showed that synthesized HBP images are visually comparable to acquired HBP images with high SSIM(0.87±0.08) and PSNR(29.6±2.25). Impact: Machine learning synthesized HBP images could provide comparable diagnostic information to acquired HBP images, suggesting that machine learning might be used to optimize clinical workflow and greatly shorten acquisition time for Gd-EOB-DTPA-enhanced MRI.
Multi-region Radiomics-based Prediction of Microvascular Invasion in Hepatocellular Carcinoma Using Multi-sequence MRI
Authors: Chen Feng , Luo Shishi , Dong Mengying , Huang Weiyuan , Liao Yuting , Yu Xiao , Xu Yongzhou
Published: November 2024

Motivation: Identifying MVI before surgery is crucial to optimizing treatment strategies and predicting prognosis. Goal(s): To develop a multi-region radiomics-based predictive model using multi-sequence MRI to assess MVI in HCC. Approach: Three Models (Tumor, Tumor-Expand5, Tumor-Expand10) were constructed and evaluated. Results: The Tumor-Expand5 model, with the best predictive accuracy, demonstrates its effectiveness. The research explores the advantages of 5mm VOI expansion for MVI diagnosis over the 10mm VOI expansion, providing valuable insights. Despite limitations, this study offers a preoperative tool to predict MVI in HCC, enhancing clinical decision-making. Impact: Predicting Microvascular Invasion (MVI) in HCC through multi-region radiomics-based MRI advances precision medicine and treatment optimization. The Tumor-Expand5 model's superior diagnostic performance demonstrates the potential to enhance clinical decision-making.
Free-breathing T2 mapping of the abdomen in half the scan time using RADTSE with deep learning reconstruction
Authors: Toner Brian , Arberet Simon , Ahanonu Eze , Goerke Ute , Johnson Kevin , Han Fei , Zhang Shu , Martin Diego , Deshpande Vibhas , Nadar Mariappan , Bilgin Ali , Altbach Maria
Published: November 2024

Motivation: Free-breathing T2 mapping of the abdomen is possible for subjects that cannot hold their breath, but current techniques require long scan times that are not always possible. Goal(s): To produce high quality T2 weighted images and T2 parameter map from highly accelerated scans of the abdomen. Approach: Combining the radial turbo spin echo sequence, navigator triggering, and new deep learning reconstruction techniques to increase the acceleration of the acquisition while maintaining image quality. Results: Using these techniques, one can produce high quality T2 weighted images and T2 parameter map of the entire abdomen in under 4 minutes. Impact: Deep learning techniques significantly reduce both scan time and reconstruction time for highly accelerated, navigator-triggered free breathing T2 weighted images and T2 parameter map of the abdomen.
Improving subtle BBB permeability estimation using iterative nonlocal estimation of multispectral magnitudes (iNESMA) filtering
Authors: Bae Jonghyun , Gong Zhaoyuan , Guo Alex , Faulkner Mary , Laporte John , Bouhrara Mustapha
Published: November 2024

Motivation: Recently, Dynamic Contrast-Enhanced MRI studies revealed increased Blood-Brain Barrier (BBB) permeability in aging and in Alzheimer’s disease (AD). However, the subtle BBB disruption in aging and in AD yields substantially low contrast extravasation, which results in an intrinsically low signal-to-noise ratio. Goal(s): An effective filtering method is desirable to suppress noise, while maintaining the spatial variation in contrast dynamics. Approach: We propose an iterative nonlocal estimation of multispectral magnitudes (iNESMA) filtering approach, which achieves noise-filtering by combining the voxels with similar spectral patterns. Results: Our results suggest that iNESMA filtering allows accurate and precise determination of kinetic parameters for subtle BBB permeability. Impact: We propose an effective, yet straightforward, filtering paradigm for improved determination of the kinetic parameters from DCE-MR images. Our proposed iNESMA filtering would allow better characterization of subtle vascular changes in aging and in AD.
Dynamic Mode Decomposition (DMD) Cardiac Phase Estimation for adult and fetal real-time MRI
Authors: Yagiz Ecrin , Tasdelen Bilal , Ozaslan Ibrahim , Jovanovic Mihailo , Tian Ye , Nayak Krishna
Published: November 2024

Motivation: Cardiac synchronization in adult and fetal imaging requires external devices (electrocardiogram, Doppler-ultrasound), which may compromise image quality and increase scan time. Self-gating with real-time imaging can mitigate this but may be less reliable for irregular motions and limited in fetal applications. Goal(s): To develop a fast image-based cardiac phase estimation method with no assumption on the heart rate and minimal user input. Approach: Dynamic Mode Decomposition is used to estimate cardiac motion signal for retrospective-gating. Results: DMD cardiac phase estimation captures cardiac motion despite the irregularities and other bulk motions, as demonstrated in real-time adult and fetal cardiac imaging, including a twin gestation. Impact: The proposed technique, Dynamic Mode Decomposition cardiac phase estimation, constructs cardiac signal with no assumption on periodicity, no iterations, and only minimal user input. This may be valuable in fetal cardiac imaging, where the cardiac signal is not readily available.
Free-breathing SMS-bSSFP myocardial perfusion imaging with prospective slice-tracking and AI-based reconstruction
Authors: Adam Naledi , Mooiweer Ronald , Tyler Andrew , Kunze Karl , Speier Peter , Stäb Daniel , Chiribiri Amedeo , Roujol Sébastien
Published: November 2024

Motivation: Simultaneous multi-slice-bSSFP shows promise for myocardial perfusion imaging with high spatial coverage/resolution. Free-breathing acquisitions are desirable but currently result in large through-plane motion. Goal(s): To develop a free-breathing SMS-bSSFP myocardial perfusion technique with high spatial coverage/resolution and prospective through-plane motion correction. Approach: Prospective slice-tracking using fastNAV was implemented into an SMS-bSSFP perfusion sequence. Image reconstruction used TGRAPPA combined with a deep learning-based complex-value image denoiser. This technique was evaluated in 10 patients undergoing two rest SMS perfusion scans with/without fastNAV. Results: The proposed approach resulted in significant motion reduction, low noise-level reconstruction, and no degradation of myocardial sharpness. Impact: This study demonstrates the feasibility of prospective slice tracking in an SMS perfusion sequence. Combined with the proposed deep learning-based reconstruction, it provides a myocardial perfusion protocol with increased spatial coverage, high spatial resolution, and feasible under free-breathing conditions.
Associations of quantitative susceptibility mapping with cortical atrophy and brain connectome in Alzheimer's disease: a multi-modal study
Authors: Yang Aocai , Ma Guolin
Published: November 2024

Motivation: Associations between abnormal quantitative susceptibility mapping (QSM), brain atrophy, and altered brain connectome in AD remain unclear. Goal(s): We aim to examine imaging markers from various MRI modalities, with a focus on their spatial correlations, to enhance our understanding of AD pathology. Approach: By combining multi-contrast MRI techniques, our study provides new insights into the overlapping relationships among brain atrophy, altered regional QSM, and brain connectome. Results: We observed a remarkable overlap between reduced cortical thickness and abnormal QSM in seven distinct brain regions. In AD patients, we identified specific regional correlations between cortical thickness and network topology from these overlapping brain regions. Impact: Our study provides new insights into the complex relationships among iron accumulation, brain atrophy, and brain connectome in Alzheimer's disease.
Subject-specific PNS prediction using a localizer and fast E-field calculation
Authors: Ertan Koray , Wade Trevor , Roemer Peter , Rutt Brian
Published: November 2024

Motivation: Given the large population variability in PNS thresholds (~3-fold), rapid and accurately prediction of PNS thresholds for individual subjects would be valuable. Goal(s): To apply our E-field-based PNS prediction method to individual subjects, and to test the hypothesis that we can predict an individual subject’s PNS threshold with reasonable accuracy. Approach: Subject-specific body models were fit to an individual’s anatomy based on a localizer. E-field calculations yielded Emax and therefore PNS threshold. We compared to measured PNS thresholds using 3 different head gradient coils and 7 different gradient directions. Results: Individual subject PNS thresholds values can be predicted to an accuracy of ~35%. Impact: There would be significant advantages in being able to predict PNS thresholds rapidly and accurately for individual subjects. This would allow much more effective use of high-performance gradient hardware, benefitting the subset of the population with high PNS thresholds.
Human Umbilical Cord Blood-Mononuclear Cell Transplantation Improves Glymphatic System Activity in Patients with Multiple System Atrophy
Authors: Shi Chuanying , Gong Dianrong , Wu Peng , Zhao Xiance , Song Peiji
Published: November 2024

Motivation: Glymhatic system as a therapeutic target for multiple system atrophy (MSA) lacks imaging markers. Goal(s): Our goal was to determine changes in imaging parameters after human umbilical cord blood mononuclear cells (hUCB-MCs) transplantation. Approach: Diffusion tensor image analysis along the perivascular space (DTI-ALPS) of MSA patients were compared with healthy controls and the ALPS indices of patients were compared before and after hUCB-MCs transplantation. Results: We found that MSA patients had lower ALPS values than health controls and that ALPS values increased after treatment. Impact: Our demonstration of a detectable decline in MSA patients and an uptick after treatment utilizing ALPS metrics provides an imaging marker to monitor the glymphatic system after hUCB-MCs transplantation.
Guided Multicontrast Reconstruction based on the Decomposition of Content and Style
Authors: Rao Chinmay , Beljaards Laurens , van Osch Matthias , Doneva Mariya , Meineke Jakob , Schülke Christophe , Pezzotti Nicola , de Weerdt Elwin , Staring Marius
Published: November 2024

Motivation: Scans within an MR exam share redundant information due to the same underlying structures. One contrast can hence be used to guide the reconstruction of another, thereby requiring less measurements. Goal(s): Multimodal guided reconstruction to reduce scanning times. Approach: Our method exploits AI-based content/style decomposition in an iterative reconstruction algorithm. We explored this concept via numerical simulation and subsequently validated it on in vivo data. Results: Compared to a conventional compressed sensing baseline, our method showed consistent improvement in simulations and produced sharper reconstructions from undersampled in vivo data. By enforcing data consistency, it was also more reliable than blind image translation. Impact: In the clinic, this can potentially enable a reduced MR exam time for a given image quality or improve image quality given a scan time budget. The former can reduce strain on the patient, whereas the latter can improve diagnosis.
Simultaneous Off-Resonance Correction and Fat-Water Separation From Center-Out Spiral Acquisition Using a Physics-Informed DL Framework
Authors: De Goyeneche Alfredo , Ramachandran Shreya , Wang Ke , Karasan Ekin , Cheng Joseph , Yu Stella , Lustig Michael
Published: November 2024

Motivation: Accelerated MRI protocols and fat/water separation are critical in clinical imaging but are compromised by off-resonance artifacts from B0 inhomogeneities, particularly in non-Cartesian trajectories with longer readouts. Goal(s): We aim to develop a deep learning framework that enables off-resonance correction from Center-Out Spiral acquisitions, enhancing scan efficiency and image fidelity without extended acquisition times, with the added value of performing fat/water separation. Approach: Our physics-informed framework employs a multi-frequency bin model trained on synthetic noise data, enabling off-resonance deblurring and extraction of fat and water components without additional acquisition steps. Results: We showcase our model's efficacy through phantom and in-vivo reconstructions. Impact: Our physics-informed deep learning framework offers off-resonance correction in Non-Cartesian Spiral MRI, enabling rapid imaging. Our model handles partial volume effects, with the added value of providing fat/water image separation.
Normative growth models for T2w 0.55T fetal brain and body MRI: population-averaged 4D atlases and volumetry centiles
Authors: Uus Alena , Verdera Jordina Aviles , Payette Kelly , Hall Megan , Silva Sara Neves , Colford Kathleen , Luis Aysha , Matthew Jacqueline , Deprez Maria , Mcelroy Sarah , Hajnal Joseph , Rutherford Mary , Story Lisa , Hutter Jana
Published: November 2024

Motivation: Low field MRI is a promising direction for fetal imaging. Yet, there are no reported models of fetal development specific to 0.55T. Goal(s): We aim to formalise normal fetal growth models for structural 0.55T MRI. Approach: We use registration-based approach for generation of spatio-temporal templates from 3D D/SVR reconstructed images of the fetal brain and body and apply deep learning segmentation to parcellate organs for volumetry from >100 control subjects. Results: This work introduces the first T2w fetal atlases and volumetry growth charts for 0.55T brain and body MRI depicting normal development across 22-38 weeks gestation. All models are publicly available online. Impact: This work is the first step toward formalisation of analysis protocols for normal fetal brain and body development and optimisation of segmentation methods for low field strength fetal MRI.
Prenatal fat-water MRI-based body composition reference charts and sexual dimorphism
Authors: Rabinowich Aviad , Avisdris Netanell , Yehuda Bossmat , Zilberman Ayala , Neeman Bar , Graziani Tamir , Khawaja Jayan , Klein Sharon Vanetik , Specktor-Fadida Bella , Herzlich Jacky , Joskowicz Leo , Ben Sira Liat , Hiersch Liran , Ben Bashat Dafna
Published: November 2024

Motivation: Preterm infants’ nutritional management should aim to replicate the intrauterine body composition. However, intrauterine body composition reference charts are lacking. Goal(s): We aimed to construct MRI-based intrauterine body mass (BM), fat mass (FM), percent FM (%FM), fat-free mass (FFM), and percent FFM (%FFM) body composition reference charts. Approach: Fetal body composition was computed from T2-weighted and fat-water images. Body and subcutaneous fat volumes were automatically segmented using neural networks, and BM, FM, %FM, FFM, and %FFM were calculated. Results: Data of 176 participants with apparently normal singleton fetuses were included. All parameters significantly changed throughout gestation, and differences between sexes were seen. Impact: MRI-based intrauterine BM, FM and FFM body composition reference charts may be used as reference for appropriate prenatal growth and may assist in nutritional management of preterm infants.
Evaluation of high-resolution fetal brain anatomical imaging with a reduced field of view using outer volume suppression
Authors: Jang MinJung , Gupta Ajay , Kovanlikaya Arzu , Scholl Jessica , Zun Zungho
Published: November 2024

Motivation: Conventional anatomical imaging of the fetal brain is limited by low resolution due to an inherently large field-of-view and a restricted matrix size. Goal(s): To achieve high-resolution fetal brain imaging and evaluate the image quality compared to conventional fetal brain imaging. Approach: Fetal brain anatomical imaging was performed using optimized outer volume suppression for higher resolution. Image quality was scored by neuroradiologists, and image sharpness was calculated using gradient norms. Results: High-resolution anatomical images acquired using our approach demonstrated improved image quality both quantitatively and qualitatively, without an increased scan time. Impact: High-resolution fetal brain anatomical imaging with a reduced field-of-view achieved by optimized outer volume suppression demonstrates improved image quality compared to conventional imaging methods. This approach may help increase diagnostic accuracy in identifying brain abnormalities in utero.
Cerebral Quantitative Susceptibility Mapping in Neonates with Congenital Heart Disease
Authors: George Elizabeth , Lee Jinhee , Martin Megan , Cui Di , Yao Jingwen , Xu Duan , Peyvandi Shabnam , Lupo Janine , Mcquillen Patrick
Published: November 2024

Motivation: QSM has potential in monitoring altered cerebral oxygenation and quantifying cerebral microhemorrhages (CMH) in neonates with congenital heart disease (CHD). Goal(s): To use 1) QSM to detect post-surgical changes in cerebral oxygenation and 2) a deep-learning algorithm to quantify CMH. Approach: Cerebral susceptibility (χ) normalized to the ventricle was compared pre- vs. post-surgery and between CHD types. Deep-learning based quantification of CMH burden was compared pre- vs. post-surgery and assessed for relationship to cardiac bypass duration. Results: Normalized post-surgery χ trended lower in neonates with transposition of great arteries compared to single ventricle physiology. Post-operative CMH burden was associated with cardiac bypass duration. Impact: QSM-derived cerebral susceptibility post-surgery varies based on lesion type in congenital heart disease (CHD), supporting a potential role for QSM in detecting cerebral oxygenation changes. Cerebral microhemorrhages are common in neonates with CHD and are associated with surgical parameters.
Ultrashort Echo Time (UTE) Spiral-VIBE MRI for Lung Nodule Detection and Radiomics Feature Stability Assessment
Authors: Li Rui , Cao Xiayin , Cui Lei , Thomas Benkert , Wu Yunzhu
Published: November 2024

Motivation: This study aims to assess the efficacy of UTE-MRI in detecting lung nodules compared to CT and to evaluate the stability of radiomics features, along with the factors influencing them. Goal(s): Through the advancement of UTE scanning technology, we strive to enable MRI to achieve lung nodule detection capability and stability on par with CT. Approach: To facilitate the clinical integration of UTE technology for lung diseases, UTE scanning was conducted on patients presenting with lung nodules. Results: UTE-MRI demonstrates a high detection rate for lung nodules larger than 6 mm, and it exhibits a high level of stability in radiomics features. Impact: Our study shows UTE showcasing a remarkable ability to detect lung nodules larger than 6 mm and maintain consistent radiomics features across repeated scans. UTE holds potential as a radiation-reducing alternative to CT for regularly monitored patients with lung nodules.
Multiparametric MRI to study changes across the Surgical Journey in Bariatric Patients with Type 2 diabetes or Prediabetes.
Authors: Spicer Abi , Wilmington Rebekah , Lloyd-Brown Stephen , Bradley Chris , Craig Martin , Simpson Elizabeth , Bawden Stephen , McCann Gerry , Aithal Guruprasad , Gowland Penny , Idris Iskandar , Francis Susan
Published: November 2024

Motivation: Bariatric surgery is evaluated by weight loss and diabetes remission, but the mechanism of the latter is unclear. Goal(s): Use MRI to quantify changes in liver, pancreas and subcutaneous adipose tissue (SAT). Approach: Multiparametric MRI of fat fraction (FF), T2*, volume, T1 and T2 at four timepoints before and after bariatric surgery. Results: Significant reduction in liver FF from baseline to 6-weeks, and between post-VLCD and 6-weeks, and liver volume from baseline to subsequent time points. Compared to baseline a significant increase in liver T2* at 6-weeks, reduction in liver T1 at 6-weeks and 6-months, and decrease in SAT at 6-monthsImpact: Multiparametric MRI assessment of changes in liver and pancreas fat, volume and T1, T2* and T2 relaxometry, as well as subcutaneous volume associated with bariatric surgery may serve as markers for longitudinal and cross-sectional assessment of patients.
Developing a body composition protocol on a commercial 0.55T MRI system
Authors: Thornley Rebecca , Ning Zihan , Whitcher Brandon , Bridgen Philippa , Bell Jimmy , Thomas E , Giles Sharon , Steves Claire , Ourselin Sebastien , Hajnal Joseph , Price Anthony
Published: November 2024

Motivation: Body composition MRI is well established at 1.5T. However there is limited work at low-field where there is growing interest, particularly with increased accessibility of ultra-wide bore systems. Goal(s): Demonstrate the feasibility of body composition MRI on a 0.55T (80cm) system, and present optimised sequence parameters suitable for large-scale studies. Approach: Dixon and liver T1 and T2*/PDFF scans were optimised iteratively by scanning subjects with a range of BMIs at 0.55T using ultra-flexible receive-array coils. Results: Body composition MRI has been demonstrated on a commercial 0.55T system. Image quality was sufficient for utilisation of an analysis pipeline established for higher field. Impact: Body composition MRI is feasible on a commercial 0.55T system, providing motivation for further protocol development. This generation of scanner presents an opportunity for more affordable and accessible MRI, with a wide bore suitable for imaging larger patients and participants.