bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal encoding strategies for turbulence quantification of undersampled 4D flow MRI
Authors: Dirix Pietro , Buoso Stefano , Kozerke Sebastian
Published: August 2024

We expand a previously developed pipeline for generation of synthetic 4D flow MRI of turbulent flows to account for realistic k-space filling and add an MR temporal averaging component to the simulations. We show that temporal averaging in typical undersampled 4D flow MRI is imperfect, leading to inherent scan-to-scan variations of measured turbulence fields. We demonstrate how encoding schemes, when designed appropriately, allow to significantly reduce scan-to-scan variability, increasing the confidence on MRI measurements.
U-JET: Preliminary results of a convolutional neural network approach for distortion-free image reconstruction of PROPELLER data
Authors: Huber Jörn , Eickel Klaus , Günther Matthias
Published: August 2024

Arterial Spin Labeling has great potential in clinics as a non-invasive alternative to Dynamic Contrast Enhanced imaging. However, motion sensitivity needs to be tackled by readout techniques such as 3D GRASE PROPELLER, which unfortunately shows a high sensitivity to geometric distortion. Analytical separation of motion and distortion effects is computationally demanding and might fail in some situations. To this aim, a U-NET based convolutional neural network approach is demonstrated which might overcome this limitation.
A tailored coil for sensitive detection of MRI signals in modulating the rat’s blood-brain barrier by focused ultrasound and microbubbles at 7T
Authors: Wu Sheng-Kai , De Maio Alessandro , Lee Hsin-Ju , Hynynen Kullervo , O'Reilly Meaghan , Lin Fa-Hsuan
Published: August 2024

Imaging-guided focused ultrasound using MRI can modulate the permeability of blood-brain barrier with high spatial accuracy. However, many MRI-guided FUS studies rely on either a body coil or head coil poorly suited to the FUS system geometry. We developed a tailored receiver coil to improve the sensitivity of 7T MRI for rats. The tailored geometry allows for a 30% SNR increase in a study modulating the blood-brain barrier permeability with microbubbles.
ADC Repeatability and Reproducibility of NCI CIRP Network Pre-Clinical MRIs
Authors: Malyarenko Dariya , Amouzandeh Ghoncheh , Pickup Stephen , Zhou Rong , Manning Henry , Gamon Seth , Shoghi Kooresh , Quirk James , Sriram Renuka , Larson Peder , Lewis Michael , Pautler Robia , Kinahan Paul , Muzi Mark , Chenevert Thomas
Published: August 2024

The goal of this work was to assess ADC repeatability, reproducibility, and bias of Co-Clinical Imaging Research Resource Program (CIRP) network MRIs using standardized procedures for comparison to corresponding performance of clinical MRIs. A temperature-controlled phantom provided an absolute reference standard and means to assess spatial uniformity of these metrics. Seven institutions participated in the study where DWI were acquired over multiple days on 10 pre-clinical scanners, from 3 vendors at 6 field strengths. Technical level repeatability and reproducibility metrics, and spatial uniformity patterns are comparable to that observed on human systems using similar phantoms and test procedures.
Stretchable conductive-thread MRI receive array coils for the knee
Authors: Narongrit Folk , Ramesh Thejas , Rispoli Joseph
Published: August 2024

We report on the development of an 8-channel stretchable array coils for 3T knee MRI which was rapidly designed using embroidered conductive threads on athletic fabric. The coil is omnidirectionally stretchable and conforms to the anatomy. Phantom testing shows the coil’s signal-to-noise ratio (SNR), and image quality are comparable to a commercial flexible coil. In vivo imaging was done on a healthy volunteer illustrates the potential of rapidly developed stretchable coils.
Modeling Mouse Placental Perfusion Dynamics and Contractions via Dynamic Contrast Enhancement MRI
Authors: Cortes Devin Raine , Stapleton Margaret , Wyman Samuel , Schwab Kristina , Coulson Noah , West Dalton , Becker-Szurszewski Thomas , Hartwick Sean , Christodoulou Anthony , Wu Yijen
Published: August 2024

Placental development is a dynamic process, and the timing of placental development events is crucial for appropriate fetal development. However, the placenta itself remains critically understudied in the context of fetal development disorders. We propose novel models for correlating DCE-MRI perfusion estimation with biologically relevant compartments and extracting dynamic biomarkers for placental development. We validate this model by demonstrating that placental perfusion is disrupted in a murine model of peri-conceptual alcohol exposure, and that this disruption occurs differently across various compartments from E14.5 to E17.5.
Gastrointestinal MRI with Conscious Rats
Authors: Wang Xiaokai , Yee Angela , Cao Jiayue , Cornett Ashley , Alkaabi Fatimah , She Yushi , Scheven Ulrich , Liu Zhongming
Published: August 2024

Anesthesia has been required for preclinical gastrointestinal MRI but may confound gastric physiology. This study demonstrates, for the first time, the feasibility of gastrointestinal MRI with awake rats, and reports the effects of anesthesia on gastric motor function. Results suggest that awake rats show greater rates of gastric emptying and intestinal filling, and stronger gastric and intestinal motility relative to those anesthetized. Anesthesia with 2.5% isoflurane can entirely stop muscle contraction. The methods and findings reported herein lay the foundation for using awake GI-MRI in preclinical studies of gastrointestinal function or dysfunction.
Contrast Kinetic Model-based GRASP Reconstruction for Small Animal Imaging at 7T
Authors: Zhang Jin , Qayyum Sawwal , Bae Jonghyun , Solomon Eddy , Kim Gene
Published: August 2024

In this study, we propose a contrast kinetic model-based GRASP (mGRASP) method which can improve the spatial image quality as well as temporal characteristics of DCE-MRI. The proposed mGRASP method was assessed with 9L rat glioma model and GL261 mouse glioma model in an Active Contrast Encoding (ACE)-MRI experiment which simultaneously measures the pre-contrast T1 and contrast kinetic model parameters including intracellular water lifetime. The results show that mGRASP provides improved image quality and temporal patterns compared to GRASP.
In vivo T1-mapping template of the mouse brain at 4.7T and 7T with a MP2RAGE sequence
Authors: Cosenza Elise , Trotier Aurélien , Massone Gauthier , Ribot Emeline , Petit Laurent , Miraux Sylvain , Ozenne Valery
Published: August 2024

3D T1 templates of the mouse brain at 7T and 4.7T were created with a MP2RAGE pulse sequence. The template was next coregistered with the DORR atlas. The resulting parcellation allows volume and T1 measurements for each labels. The values obtained can be compared according to the magnetic field, intra and inter individual. Volumes were found in agreement with the literature. The T1 measurements are reproducible between individuals and significantly different at 4.7T and 7T.
3D Isotropic and high resolution whole brain DWI with single slab and single shot EPI utilizing motion compensated diffusion gradients
Authors: Wu Zhigang , Zhang Yajing , Guillaume Gilbert , Su Wengu , Zhao Yan , Wang Jiazheng
Published: August 2024

3D Diffusion imaging (3D DWI) has showed great potential in probing tissue microstructure and brain structural connectivity. However, motion-induced phase errors introduced by diffusion gradients will cause severe artifacts in 3D DWI. Multi-slab can be used to overcome this limitation, but it will introduce slab boundary artifacts. We propose a method which utilizes motion-compensated diffusion gradients for 3D DWI to mitigate the phase error between shots. Results from in vivo data demonstrate the proposed method can improve image quality and realize an isotropic high resolution and whole brain 3D DWI in a single slab.
Sub-millimeter Diffusion Tensor Imaging using Single-Shot Spiral Acquisitions with a Large Acceleration Factor
Authors: Li Guangqi , Ye Xinyu , Lian Yuan , Zhang Yajing , Guo Hua
Published: August 2024

Single-shot spiral acquisitions allow shorter TE, thus provide higher SNR compared to EPI acquisitions for DWI. However, spiral acquisitions are sensitive to field inhomogeneity. Parallel imaging techniques can be used to alleviate static B0 off-resonance effects. In this study, single-shot spiral acquisitions with a large acceleration factor of 5 or 6 were used to achieve sub-millimeter diffusion tensor imaging at 3T. The in vivo results demonstrate that the single-shot spiral sampling strategy can be adopted to achieve whole-brain diffusion tensor imaging with an in-plane resolution of 0.77×0.77mm2.
A NEW METHOD TO ANALYSE RENAL PERFUSION: A PROOF OF CONCEPT
Authors: Serpa Luis Sanmiguel , De Visschere Pieter , Speeckaert Marijn , Pullens Pim
Published: August 2024

To date, renal ASL MRI images are analysed with methods that may underestimate renal perfusion or that may be observer-dependent. In this study, we implemented two analysis methods that take into account the complex morphology of the kidney. One analyses the kidney progressively, from the cortex to the medulla, and the second one, a new algorithm analyses the kidney in radial sections. Our results show that perfusion values change across the kidney and that healthy subjects have higher perfusion values. This study shows the importance of using more robust analysis on kidney ASL MRI images.
Higher Field Reduced-FOV Diffusion-Weighted-Imaging for Abdominal Imaging at 5.0 Tesla: Image Quality Evaluation Compared with 3.0 Tesla
Authors: Zhang Yunfei , Dai Yongming , Zeng Mengsu
Published: August 2024

Reduced field-of-view (rFOV) technique is a feasible approach to counter the constraints of conventional DWI. Most recently, the 5.0 T whole-body MRI system was developed, which provides an alternative choice for high field abdominal DWI. This research aims to evaluate the image quality of 5.0 T rFOV-DWI with the 3.0 T rFOV-DWI as the reference. The results indicated that 5.0 T rFOV-DWI had better overall image quality and improved SNR compared to 3.0 T rFOV-DWI, which holds clinical potential for identifying the abdominal abnormalities in routine practice.
Effect of age on the evaluation of left ventricular kinetic energy from 4d-flow CMR
Authors: Zhang Jingyu , Tian Di , Xiong Ziqi , He Yifan , Li Zhiyong
Published: August 2024

Four-dimensional flow cardiovascular magnetic resonance imaging (4d-flow CMR) left ventricular kinetic energy (LVKE) parameter Peak A- wave KEiEDV increased, KEiEDV E/A ratio decreased with age. This suggests that 4d-flow CMR LVKE parameters can respond to age-induced changes in LV diastolic function.
Cerebellar gray matter volume and cerebellum-cerebral connectivity associated with freezing of gait in patients with multiple system atrophy
Authors: Yang Huaguang , Liu Weiyin Vivian , Li Liang , Wen Zhi , Hu Lanhua , Luo XiaoGuang , Zha Yunfei
Published: August 2024

Cerebellum is responsible for posture and gait control. 65.93% of patients with multiple system atrophy experienced FOG. Patients with the damaged cerebellar locomotor region had gait-freezing-like symptoms, suggesting that the cerebellum may be involved in the occurrence and development of FOG symptoms. This study suggested that the cerebellum volume atrophy may be involved in FOG development in MSA patients and subsequently induce functional abnormality in the cerebellum-cerebral circuit. This study provided neuroimaging evidence for clinical understanding of cerebellum role in MSA patients with FOG injury.
A Magnetic Resonance Spectroscopy Method in Characterization of Urine Metabolomics for Prostate Cancer
Authors: Cheng Leo , Hasubek Anna-Laura , Feldman Adam
Published: August 2024

Currently, Prostate Cancer (PC) diagnosis is achieved either through invasive measures, like biopsies, or imaging techniques, such as sonography, CT, and MRI. The biomarker PSA in blood is used for screening, however its use is considered controversial. It doesn’t show to reduce PC all-cause mortality and PSA screening comes with a high number of false-positive results and associated risks. Here, using HRMAS MRS, we studied human urine samples obtained from prostate cancer patients and healthy controls to reveal potential PC-associated metabolomic changes, which may assist with early and non-invasive PC diagnosis and screening.
Direct comparison of deuterium 2H MRSI at 3T vs 7T
Authors: * Jabrane Karkouri , * Mary McLean , * Minghao Zhang , Kaggie Joshua , Grimmer Ashley , Khan Alixander , Matys Tomasz , Atkinson Daniel , * Ferdia Gallagher , * Christopher Rodgers
Published: August 2024

Deuterium metabolic imaging (DMI) is a new method to probe brain metabolism. Theory predicts higher SNR at higher field strength, but clinical translation is easier at lower field strength. We undertook 2H MRSI in 3 healthy volunteers at 3T and 7T sequentially. Acquisition was undertaken at baseline and after 11.1g oral D2O consumption. Data quality was acceptable in all scans. SNR was 3x higher at 7T, in agreement with theory. D2O cerebral uptake rate was similar between field strengths (0.13 min-1 at 3T vs 0.07 min-1 at 7T).
Deep Learning Reconstruction for Magnetic Resonance Image Quality Improvement in Lumbar Endplate Inflammation
Authors: Lv Xinyang , Ye Zheng , Zhang Miaoqi , Zhang Bo , Li Zhenlin
Published: August 2024

Magnetic resonance imaging (MRI) is a useful tool to diagnose lumbar endplate inflammation. It is thus important to improve diagnostic accuracy by improving image quality. In this study, we compared signal-to-noise ratio (SNR), contrast noise ratio (CNR) and subjective scores between original images and deep learning reconstruction (DL Recon) images in 31 patients diagnosed with lumbar endplate inflammation. It was observed that the deep learning reconstructed images outperformed conventional images in terms of both subjective scores and objective values.
Development and application of dynamic MRSI of an HP neuroprotective agent in an MCAO mouse model of ischemic stroke at 14.1 T
Authors: Lê Thanh Phong , Buscemi Lara , Lepore Mario , Capozzi Andrea , Hirt Lorenz , Mishkovsky Mor , Hyacinthe Jean-Noël
Published: August 2024

Advanced acquisition hardware and sequences boosting the spatiotemporal resolution overcome the existing limitations of HP metabolic MRI in animal disease models, providing new contrasts and opening up new perspectives. Herein, we designed a 1H/13C volume/surface-combined head coil providing full mouse brain coverage with high sensitivity, as well as a high-efficiency acquisition scheme to achieve superior spatial and temporal resolution images. This setup was employed for time-resolved imaging of the cerebral metabolic response to a neuroprotective bolus of hyperpolarized pyruvate in a transient hypoxia/ischemia mouse model. The experiments suggest a distinct metabolism between the ischemic and healthy tissues.
A comparison of navigator-free multi-shot spiral and EPI in high-resolution DWI
Authors: Li Guangqi , Li Sisi , Guo Hua
Published: August 2024

Navigator-free multi-shot spiral and EPI acquisitions have been developed to achieve 2D high-resolution diffusion imaging. In this study, we investigated the off-resonance effects of spiral and iEPI samplings with different partial Fourier factors based on a signal model. Moreover, the SNR performances of the two multi-shot acquisitions at different resolutions and TEs were also explored. In summary, compared with iEPI, spiral provides superior SNR in multi-shot navigator-free DWI at various resolutions and TEs, even when the TE of spiral acquisition is slightly longer than that of iEPI. However, off-resonance correction for spiral sampling with ultra-long readout durations is more challenging.
Study of Oxidative Stress due to X-ray Irradiation in Mouse Brain using TOLD MRI Imaging
Authors: Parajuli Raj , Ueno Megumi , Suzuki Saaya , Sumiyoshi Akira , Obata Takayuki , Aoki Ichio , Matsumoto Ken-ichiro
Published: August 2024

This study aims to evaluate the metabolic changes caused on the brain tissues due to radiation exposure to healthy tissues while tumor treatment. The tissue oxidization and reduction mechanism represented by redox imaging could be a suitable index to evaluate in vivo oxidative stress in living animals that could evaluate metabolic damages due to irradiation. We adopted tissue oxygen level dependent (TOLD) MRI imaging to analyze TOLD signal for the control group mice and the irradiated mice. The result shows the distinct oxygen consumption levels in the control and the irradiated mice.
Zero-echo time (ZTE) pulse sequence enables EEG-fMRI with suppression of susceptibility artifacts.
Authors: Imamura Ayako , Araki Rikita , Takahashi Yukari , Miyatake Koichi , Kato Fusao , Honjoh Sakiko , Tsurugizawa Tomokazu
Published: August 2024

Simultaneous recording of fMRI and EEG is a promising approach to realize functional brain imaging with high temporal and spatial resolution. However, using standard echo planar imaging in conventional fMRI studies, implantation of electrodes on the cortical surface induces strong magnetic susceptibility artifacts in fMRI images. The zero-echo time (ZTE) sequences show a remarkable reduction in sensitivity to magnetic susceptibility artifacts and motion-derived artifacts. In this study, we showed that the ZTE sequence suppressed the susceptibility artifact by electrodes and air in the ear canal in mice. Furthermore, ZTE showed the typical functional connectivity in the mice at resting state.
BOLDSwimSuite: A Python-based tool suite for numerical simulations of transverse relaxation in the presence of diverse field perturbers
Authors: Chaussé Jacob , Berman Avery , Chen J.
Published: August 2024

Numerical simulations are valuable tools for understanding the transverse relaxation process, but their use is impeded by computational complexities and a lack of standard in simulation pipelines. We present a new software suite (named BOLDSwimSuite) to address these challenges, making numerical simulations accessible to a wider community of researchers. Among its many features, this toolbox is able to accommodate arbitrary magnetic-field perturbers as well as simulate different MRI sequences. This toolbox is useful for investigating BOLD fMRI contrast and MR vascular fingerprinting among other applications.
Quantitative Evaluation of Deep Learning Reconstruction of Diffusion-weighted MRI using a DWI Phantom
Authors: Kong Xiangchuang , Tao Shengzhen , Middlebrooks Eric , Benkert Thomas , Zhou Xiangzhi , Lin Chen
Published: August 2024

In a quantitative phantom study, deep learning (DL) reconstruction is shown to improve the SNR ratio of DWI images while preserving measured ADC values. The average SNR gain is similar to that achieved with better gradient performance between Siemens Prisma and Vida. Such benefits of DL recon should allow better quality and/or shorter scanning of DWI in clinical applications.
Investigating muscle micro-trauma with time-dependent diffusion and the random permeable barrier model
Authors: Rauh Susanne , Cameron Donnie , Gurney-Champion Oliver , Maas Mario , Froeling Martijn , Kan Hermien , Nederveen Aart , Strijkers Gustav , Hooijmans Melissa
Published: August 2024

Repetitive muscle micro-trauma can result in severe muscle injuries. Diffusion tensor imaging can detect small but significant changes due to muscle micro-trauma, but the sensitivity is limited. Longer and multiple diffusion times can potentially increase the sensitivity to micro-trauma as they facilitate muscle fiber diameter and permeability estimations with the random permeable barrier model (RPBM). In this study, we demonstrated that a diffusion time of 116.7ms showed largest percentage change in DTI indices suggesting an increased sensitivity to exercise-induced muscle micro-trauma after running a marathon. No effect was found in the RPBM-derived membrane permeability and fiber diameter.
Imaging of the Contraction Pattern of Spontaneous Muscular Activities using a Multiple-Point Diffusion-Weighted Stimulated Echo Sequence
Authors: Schwartz Martin , Martirosian Petros , Steidle Guenter , Yang Bin , Schick Fritz
Published: August 2024

Spontaneous mechanical activities in resting musculature can be visualized using stimulated-echo or spin-echo diffusion-weighted sequences. Temporal resolution is limited to the sampling of one point in time of the contraction pattern. Therefore, a concept for multiple points in time imaging of spontaneous activities is proposed in this work. The implemented MR sequence was validated by measurements from a water phantom and of the resting lower leg musculature of healthy subjects.
Understanding Loss Mechanisms in Double-Tuned Body Coils To Improve B1 Efficiency
Authors: Kahraman-Agir Busra , Welting Dimitri , Gosselink Mark , Klomp Dennis
Published: August 2024

Double-tuned circuits are often comprised of internal resonances in tank circuits that locally may amplify RF currents and thereby cause extra loss compared to single tuned RF coils. Here, we investigated the loss mechanisms of RF borecoils for the operating frequencies of 120.68, 78.8 and 45.8MHz for the purpose to design a B1+ efficient multi-tuned RF borecoil for metabolic MRI of 2H, 23Na and 31P, respectively at 7T.
Improved Dynamic In Vivo pH Imaging Using Hyperpolarized 13C-bicarbonate
Authors: Liu Xiaoxi , Mu Changhua , Lai Ying-Chieh , Bok Robert , Santos Romelyn Delos , Kim Yaewon , Sinha Avantika , Gordon Jeremy , Flavell Robert , Larson Peder
Published: August 2024

We present a dynamic pH measurement using metabolite-specific gradient-echo spiral sequence with flow suppression to improve the SNR of bicarbonate and CO2 with short T2* and used bipolar gradients to suppress the high bicarbonate signal in the vessel. With the improved image quality and high temporal resolution, it is possible to measure the dynamic pH in vivo. Future studies will work to increase the sample size to confirm these results.
Comparison of NATIVE-TrueFISP and 3D-SPACE in the magnetic resonance cholangiopancreatography of patients with ascites at 3T scanner
Authors: Huang Lanbin , Zhong Jinglian , Liao Liping , Huang Yingying , Liu Zeping , Li Qingchun , Ruan Qiceng , Tan Mingxia , Wang Mengzhu , Liao Shasha , Huang Zehe , Chen Song
Published: August 2024

To compare the image quality of NATIVE-TrueFISP and 3D-SPACE in the MRCP of patients with ascites at 3T scanner. 5 patients with ascites and another 5 patients without underwent conventional upper abdominal MRI and MRCP with two kinds of sequences: NATIVE-TrueFISP and 3D-SPACE. The image quality of the two MRCP methods were independently assessed by two readers. Image quality of 3D-SPACE was superior to TrueFISP in patients without ascites while the TrueFISP sequence achieved better duct visualization in patients with ascites. Native TrueFISP can be used as an optional fast imaging sequence for MRCP of patients with ascites.
SSc primary heart involvement assessed by cardiovascular magnetic resonance imaging and explore its relationship with the skin involvement
Authors: Zhao Yanan , Cui Jianing , Yue Xiuzheng , Li Tao
Published: August 2024

Cardiac involvement is a significant cause of morbidity and mortality in subclinical systemic sclerosis (SSc). There are, however, no effective methods for detecting cardiac involvement in a general, asymptomatic SSc cohort. We aim to characterize SSc-primary heart involvement (SSc-pHI) through cardiovascular magnetic resonance (CMR), exploring the relationship between SSc-pHI and skin involvement by modified Rodnan skin score (mRSS). We found that 71% of SSC patients had Late gadolinium enhancement (LGE) fibrosis, and 75% and 46% had anomalous native T1 and extracellular-volume fraction (ECV). In addition, SSc-pHI is related to the severity of skin involvement.
Predict late gadolinium enhancement using left ventricular long-axis strain in multiple myeloma with secondary cardiac amyloidosis patients
Authors: Hu Mengyao , Song Yipei , Kan Ao , Dai Jiankun , Gong Lianggeng
Published: August 2024

The purpose of this study was to evaluate the function of left ventricular (LV) in multiple myeloma (MM) with secondary cardiac amyloidosis (MM-CA) patients by cardiac magnetic resonance feature tracking (CMR-FT), and investigate the role of simple and fast CMR-FT long-axis strain (LAS) analysis in predicting late gadolinium enhancement (LGE). The results showed the LV function was more impaired in enhanced (LGE+) than in no-enhanced (LGE-) MM-CA patients. Among the investigated CMR-FT parameters, the LV LAS presented with best prediction efficacy of LGE. Our study indicated the simple and fast LAS may be beneficial for MM-CA patients with renal failure.
Comparison of Intra-Hippocampal Fiber Tracks and Connectomes between Alzheimer’s Patients and Age-Matched Healthy Controls
Authors: Overson Devon Karl , Ma Yixin , Truong Trong-Kha , Madden David J. , Petrella Jeffrey R. , Song Allen
Published: August 2024

Changes in intra-hippocampal connectivity caused by early neurodegeneration in specific hippocampal subfields could serve as a biomarker for the early diagnosis of Alzheimer’s disease (AD), years before the onset of symptoms, when the neurodegeneration may still be reversed by treatments. Here, we use high-resolution DTI to compare intra-hippocampal fiber tracks and connectomes across different hippocampal subfields in AD patients and age-matched healthy controls. A significant (p < 0.01) decrease in number of streamlines was found in the AD group compared to the control group for four pairs of subfields, independently of a reduced hippocampal volume affecting nearly all subfields.
Does intravoxel incoherent motion MRI measure tumor perfusion? A comparison with DCE-MRI in patients with breast cancer.
Authors: Almutlaq Zyad , Bacon Sarah , Wilson Daniel , Sharma Nisha , Buckley David
Published: August 2024

DCE-MRI can provide quantitative estimates of perfusion-related parameters in tumors, such as blood flow and blood volume fraction. It has also been proposed that IVIM MRI can be used to characterize perfusion in addition to microstructure. This proposal remains controversial and requires further investigation. In this study, we investigate the relationship between perfusion-related parameters measured by IVIM and DCE-MRI in a cohort of patients with breast cancer imaged before and after one and two cycles of neoadjuvant chemotherapy.
Optimising an Acquisition Protocol and Pipeline for Robust Clinical Quantitative Susceptibility Mapping to Investigate Movement Disorders
Authors: Kiersnowski Oliver , Thomas David , Yamamoto Adam , Elgwely Mohammed , Papadaki Anastasia , Yousry Tarek , Thornton John , Shmueli Karin
Published: August 2024

Quantitative susceptibility mapping (QSM) has been used to investigate movement disorders but has not been integrated into routine clinical practice. We developed an acquisition protocol and a robust QSM pipeline for neuroradiological investigation of movement disorders. We show that high quality QSMs can be acquired using a multi-echo 3D gradient-echo sequence with partial k-space filling in under 6 minutes with only one of eleven patient QSMs corrupted by motion artifacts. We show that Laplacian phase unwrapping and projection onto dipole fields (PDF) background field removal are robust to artifacts across patients with strong susceptibility sources associated with various pathologies.
GRAPPA acceleration of Cartesian magnetic resonance fingerprinting (MRF) at 7T
Authors: Shirvani Saba , Ding Belinda , Dragonu Iulius , Rodgers Christopher T.
Published: August 2024

MR fingerprinting enables for robust simultaneous quantitative parametric mapping and is usually performed with spiral acquisitions. These are particularly sensitive to B1 inhomogeneities and hence more susceptible at ultra high-field. To mitigate B1 inhomogeneity effects, we implemented a Cartesian MRF approach. Cartesian 2D data collection time is somewhat slow, and we overcome this by demonstrating the feasibility of GRAPPA acceleration for applications in phantoms and in vivo. We present a fully sampled Cartesian data set in a phantom and in vivo, and we present the performance of increasing GRAPPA acceleration factors to reduce scan time significantly, without compromising image quality.
A Systematic Comparison of Different Dipole Antenna Array Configurations for Knee Imaging Applications at 7T.
Authors: Bhosale Aditya , Ying Leslie , Zhang Xiaoliang
Published: August 2024

In this study, we investigate different multi-channel array configurations formed by various dipole antenna types and compare the array configurations in B1+ field maps, SAR maps, and inter-element isolation for knee imaging at the ultrahigh field of 7T.
RF Interference Removal in Multi-Channel Receive coil
Authors: Agarwal Harsh , Venkateshan Ramesh
Published: August 2024

RF Interference can severely degrade the performance of an MR system. Several solutions such as RF shielding, waveguides and special filters are used to send and receive data to the MRI scanner. These solutions constitute significant part of MR installation and maintenance cost. RF interference in multi-channel receive MR system is strongly correlated across multiple receive channels. This correlation is exploited in this manuscript to remove/suppress the artifacts in the MR images arising due to RF interference. Initials results are demonstrated on 1.5T commercial MRI scanner with data acquired with open RF cage door.
Comparison of multiplexed sensitivity encoding and single-shot diffusion-weighted echo-planar imaging of the lung: Preliminary study
Authors: Fang Longjiang , Zhao Wenjing , Chu Yujing , Wang Qi , Pylypenko Dmytro
Published: August 2024

This study aims to compare multiplexed sensitivity encoding (MUSE) and single-shot diffusion-weighted echo planar imaging (SS DWEPI) techniques in lung MRI. A total of 22 patients with lung lesions were recruited in the study. Qualitative parameters included anatomic details, suscepti-bility artifacts, and diagnostic confidence; quantitative parameters included SNR and ADC of the lesions. The statistical studies demonstrated results that prove MUSE can provide better anatomic detail, lower susceptibility artifacts, higher diagnostic confidence, and improved SNR of the lung. MUSE is a promising technique for both clinical MRI diagnosis and treatment planning for lung lesions.
Susceptibility-based Positive Contrast Imaging of MR Compatible Metallic Devices Using Model-based Deep Learning
Authors: Shi Caiyun , Cheng Jing , Liu Xin , Zheng Hairong , Zhu Yanjie , Liang Dong , Wang Haifeng
Published: August 2024

Susceptibility-based positive contrast MR imaging exhibits excellent efficacy for visualizing the MR compatible metallic devices, by taking advantage of their high magnetic susceptibility. In this work, a model-based deep learning architecture with U-net is developed to realize the 3D susceptibility-based positive contrast MR imaging on real phantom experiments. We train the network on synthetic data to generate positive contrast images from magnetic field maps for localizing the seeds from their surroundings and demonstrate the potential of the deep learning implementation.
PET-MRI lymph node analysis, a predictive tool for recurrence in upper aerodigestive tract cancers
Authors: Pyatigorskaya Nadya , Sclover Yoann , Kas Aurelie , Yahia-Cherif Lydia , Amor Melika Sahli
Published: August 2024

The aim of our study was to analyze the imaging characteristics of lymph nodes on pre-operative PET-MRI to find the predictors of recurrence or progression.273 patients with ATD cancer who underwent PET-MRI were included. Lymph node PET/MR analysis has shown that the strongest predictors of the recurrence were lymph node enhancement and SUVmax for the controlateral nodes and enhancement, SUVmax node shape for the homolateral nodes. In conclusion, PET-MRI can be an interesting tool in the pre-therapeutic assessment of primary tumors of the ADT with lymph node extension, particularly in the identification of predictive characteristics of recurrence or progression.
Development of Small Animal PET-insert Compatible RF Coils for Simultaneous 129Xe MRI/15O2-PET Brain Perfusion Measurements
Authors: Woodward Elise , Lim Heeseung , Sembhi Ramanpreet Kaur , Fox Matthew , Ouriadov Alexei
Published: August 2024

This study aims to present two birdcage radiofrequency (RF) coils for the use of simultaneous hyperpolarized Xenon-129 (129Xe) MRI and 15O2 PET imaging for brain perfusion measurements. Coils were designed for use with a 2.89T Siemens scanner, or 34.05MHz, one using a low pass filter design, and the other a high pass filter design.
An 8-Parallel Transmit 32-Receive Array Head Coil for Clinical Use at 7.0 Tesla
Authors: Smerglia Alexander , Petropoulos Labros , Yang Xiaoyu , Zheng Tsinghua , Taylor Paul , Whitesell Blaise , Sidhu Jagjit , Sakaie Ken , Lowe Mark
Published: August 2024

An 8-parallel transmit 32-Rx head coil was built and evaluated for performance in high-field MRI. The coil is comprised of an 8-rung curved degenerate birdcage transmitter and a 32-loop element receive array. The coil housing was designed with an anterior/posterior split and eye windows for patient comfort, and a sizable interior that can fit 99 percent of the general population. A volunteer was imaged to confirm transmit coverage, which includes the entire brain and upper cervical spine. Good B1 uniformity, and improved transmit efficiency over previously built non-curved Tx head coils were also confirmed.
Optimized interferometric encoding of presaturated TurboFLASH B1-mapping for pTx at 7T MRI: Application to T1-mapping in the spinal cord
Authors: Destruel Aurelien , Mauconduit Franck , Massire Aurélien , Gras Vincent , Callot Virginie
Published: August 2024

One of the best solutions to B1 inhomogeneities observed at ultra-high field MRI is to use parallel transmit techniques (pTx). However, fast and accurate knowledge of the B1+ is required. The presaturated TurboFLASH (satTFL)-based B1-mapping sequence, with interferometric encoding, has shown great promise due to its speed and reliability, but it was observed that its performance may drop when used with unconventional radiofrequency coils and applications. In this study, a novel optimization of the interferometric encoding is presented and applied to cervical spinal cord MRI at 7T. The impact of having improved B1-maps is evaluated on pTx MP2RAGE-based T1-mapping.
A Flexible iPRES AIR Coil Array for MRI and Localized B0 Shimming
Authors: Overson Devon , Darnell Dean , Robb Fraser , Song Allen , Truong Trong-Kha
Published: August 2024

Susceptibility-induced B0 inhomogeneities can cause artifacts that severely degrade the image quality in many applications. Integrated parallel reception, excitation, and shimming (iPRES) coil arrays can perform MRI and localized B0 shimming with a single coil array, but are so far rigid, which limits their SNR and shimming performance. Here, we develop a flexible iPRES coil array that can conform to the subject’s anatomy and substantially improve the SNR and reduce the B0 inhomogeneities and geometric distortions in diffusion-weighted imaging of the knee compared to a rigid iPRES coil array, which will be valuable for many anatomical regions and applications.
Design Optimization of an Hybrid Multi-Coil Array for In Vivo Human Brain B0 Shimming
Authors: Theilenberg Sebastian , Ianniello Carlotta , Igwe Kay , Brickman Adam , Juchem Christoph
Published: August 2024

The multi-coil (MC) technique utilizing a set of individually driven non-specific coils outperforms traditional spherical harmonics B0 shimming in rodent and human brains. MC designs consisting of dedicated MC elements have shown the best shim performance, while designs utilizing a DC current on the RD coil of RF coil arrays have slightly lower performance but need significantly less physical space. Here, we optimized the number, size and placement of dedicated MC elements to be used in combination with RF-DC coils in a hybrid MC shim system for B0 shimming of the human brain in a clinical 3 T MR scanner.
Magnetic Resonance Imaging of Central Vein in the diagnosis of Stuck Hemodialysis Central Venous Catheter: A Case report
Authors: Jin Zhe , Yang Ruimeng , Xu Yongzhou , Wu Peng , Zeng Faith , Wei Xinhua
Published: August 2024

The stuck central venous catheter (CVC) results from fibrin sheaths that firmly adhere the catheter to the wall of the superior vena cava or right atrium. Here, we report a patient with stuck CVC. The patient underwent preoperative magnetic resonance imaging (MRI) of the central vein to remove the catheter and then suffered intraoperative cardiac arrest with a bedside ultrasound suggesting cardiac tamponade and considered a right atrial laceration. The patient was then transferred to ICU, where he was discharged over a week later with stable vital signs, pending further surgery. The preoperative MRI features were analyzed retrospectively.
Using Magnetic Resonance Spectroscopy for Metabolomic Characterization of Blood Serum in Patients with Myocardial Fibrosis
Authors: Cheng Leo , Füzesi Mark , Wang Xiaoyu , Leist Antonia , Hasubek Anna-Laura , Yu Paul
Published: August 2024

Myocardial fibrosis plays a key role in the pathological remodeling of the diseased heart. Yet, there is currently no routine screening method for it. The gold standard, histological examination, is highly invasive. Other alternatives are either costly (e.g. PET-CT, MRI) or subjective (echocardiography). Using HRMAS MRS, we analyzed blood samples from subjects diagnosed with common myocardial fibrosis (MF), amyloidosis (CA), or sarcoidosis (CS), plus controls. The identified regions of interest (ROI) and principal components (PC) enabled us to distinguish between diseased and not-diseased, and between the different disease groups. This may contribute to earlier diagnosis and increased success of treatment.
Investigating changes in brain lactate compartmentation using diffusion-weighted MRS in APP/PS1 mice
Authors: Malaquin Sophie , Mougel Eloïse , Lerchundi Rodrigo , Valette Julien
Published: August 2024

Diffusion-weighted MR spectroscopy yields information about the microstructure of the environment where brain metabolites are diffusing. Here, we measure the diffusion of two purely intracellular metabolites (astrocytic myo-inositol and neuronal N-acetyl aspartate) and of lactate, which is also present in the extracellular space, in the cortex of 12-month-old APP/PS1 and control mice. While astrocytic and neuronal microstructures appear unchanged in APP/PS1 mice, lactate diffusion appears slower. Modeling DW-signals suggests decreased extracellular lactate fraction.
G-ratio Calculation in Multiple Sclerosis: The Impact of Diffusion Modelling for Axonal and Fiber Volume Fraction Determination
Authors: Joseph Tigris , Kolind Shannon , Zhao Guojun , Sun Peng , Carruthers Robert , Schabas Alice , Sayao Ana-Luiza , Devonshire Virginia , Tam Roger , Wayne Moore G. R. , Li David , Song Sheng-Kwei , Traboulsee Anthony , Vavasour Irene , Laule Cornelia
Published: August 2024

G-ratio is the ratio of the inner axonal diameter to the total outer diameter, including myelin. MRI-derived g-ratios in multiple sclerosis (MS) may convey microstructural tissue abnormalities. G-ratios were estimated using myelin water fraction scaled to myelin volume fraction, and axonal metrics from Diffusion Basis Spectrum Imaging (DBSI), Neurite Orientation Dispersion and Density Imaging (NODDI), Spherical Mean Technique (SMT), and ActiveAx for axon/fiber volume fraction in 122 MS patients. DBSI and ActiveAx derived g-ratios were higher in lesions than normal appearing white matter (NAWM), reflecting MS pathology. NODDI and SMT derived g-ratios were unexpectedly lower in lesions than NAWM.
A multi-compartment fingerprinting model for non-invasive tumor cell characterization via diffusion MRI
Authors: Dausort Manon , Delinte Nicolas , Dessain Quentin , Bulcke Colin Vanden , Macq Benoit
Published: August 2024

Brain tumor tissue characteristics are important for treatment planning but are nowadays often recovered via invasive biopsy analysis. This work attempts to characterize the microstructural properties of tumor cells using diffusion MRI and Monte Carlo simulations to build a dictionary composed of several fingerprints, combining both a representation of axonal fibers and tumor cells. We demonstrate the use of our method on in-vivo brain data as a reliable estimation of tumor cell properties.
Investigating Rb vapor density and temperature distributions in a high throughput 129Xe-Rb polarizer
Authors: Ball James , Wild Jim , Norquay Graham
Published: August 2024

Accurate knowledge of the Rb vapor density, [Rb], is essential for optimizing 129Xe polarization (PXe) and production rates in clinical-scale 129Xe-Rb SEOP hyperpolarizers, used for hyperpolarized 129Xe MRI. We used atomic absorption spectroscopy to measure [Rb] for multiple Rb transitions to assess [Rb] measurement accuracy and extend [Rb] measurement range sensitivity. It was shown that [Rb] is significantly lower than saturation [Rb] and that [Rb] homogeneity was improved by implementing a larger Rb source distribution or a presaturator. The 129Xe-Rb spin-exchange cross section, $$$\gamma^\prime$$$, was determined to be $$$\gamma^\prime$$$= (1.2± 0.1) ×10−21m3s−1 for our operating conditions.
A novel compartmental model of 129Xe gas exchange using blind estimation of blood concentration
Authors: Taylor Yohn , Parker Geoffrey , Kim Mina , Jimenez-royo Pilar
Published: August 2024

Preclinical to clinical translation of pulmonary gas exchange measurements utilising hyperpolarised 129Xe MRI is limited by the overlapping spectral peaks of dissolved 129Xe MR red blood cell (RBC) and tissue compartments in some preclinical species. We present a novel kinetic model of 129Xe exchange (KMXE) in conjunction with blind estimation techniques to evaluate 129Xe exchange between pulmonary tissue and blood without needing an explicit measurement of RBC signals. Using simulations, we show that kinetic parameter estimates are comparable to those estimated using conventional methods, demonstrating feasibility for evaluating gas exchange kinetics when no distinct RBC spectral peak can be measured.
Healthy reference distributions for 129Xe gas exchange MRI with consideration of sex and hemoglobin
Authors: Bechtel Aryil , Mummy David , Lu Junlan , Leewiwatwong Suphachart , Mammarappallil Joseph , Kabir Sakib , Driehuys Bastiaan
Published: August 2024

129Xe gas exchange MRI is commonly quantified by binning images of ventilation, membrane uptake (M/gas), and red blood cell transfer (RBC/gas) according to thresholds established using healthy reference distributions. To date, reference values have been based on small samples and do not account for hemoglobin concentration (Hb), which is known to vary by sex. We apply a Hb correction to data from 15 young, healthy volunteers (age=25.2±3.3 yrs., 6 female). After correction, there was no significant difference in individual mean M/gas and RBC/gas between males and females. The resulting reference distributions have less dispersion and skew than previously established distributions.
Repeatability of pulmonary 129Xe static spectroscopy and dynamic spectroscopy fit methods: a reader study
Authors: Bechtel Aryil , Costelle Anna , Bier Elianna , Lu Junlan , Mammarappallil Joseph , Kabir Sakib , Mummy David , Driehuys Bastiaan
Published: August 2024

129Xe MRS measures static and dynamic spectral parameters from 129Xe signal in airspaces, membrane tissues, and red blood cells (RBC) and has the potential to characterize cardiopulmonary diseases. However, a better understanding of measurement repeatability is needed, and different approaches to quantifying cardiogenic oscillations have been proposed. Here, we compare quantification of oscillations using sine-fitting and a peak-finding algorithm and use reader ratings to identify acceptable study quality. Across a range of cardiopulmonary disease groups, measurements of static parameters showed good intra-session repeatability while the peak-finding algorithm generally yielded higher repeatability than sine fits for most dynamic parameters.
The Yale Glioma Dataset: Developing An Open Access, Annotated MRI Database
Authors: Sala Matthew , Lost Jan , Tillmanns Niklas , Merkaj Sara , von Reppert Marc , Ramakrishnan Divya , Bousabarah Khaled , Huttner Anita , Aneja Sanjay , Avesta Arman , Omuro Antonio , Aboian Mariam
Published: August 2024

Recent development of Machine Learning (ML) tools for analysis of CNS tumors demonstrates great potential benefit to research and clinical practice but has been hindered by a lack of external validation. There is a critical need for open access to large individual hospital-based datasets with expert annotations. Here, we present the Yale Glioma Dataset, a database of 1,033 patients featuring annotated segmentations on FLAIR and T1 post-gadolinium, tumor grading and classification, and further clinical information. Open access of this database will support the development and validation of new AI algorithms for glioma detection and segmentation.
Finite element simulation of breast hyperelasticity to develop a non-rigid registration model by deep learning
Authors: OUADAHI Fares , PETER Aurélie , BERNARD Anaïs , ROUYER Julien
Published: August 2024

This work is part of an ongoing study to correct accidental breast motion during dynamic contrast-enhanced imaging. Here, we explored a finite element method to generate “moving” images based on a “fixed” one. The proposed methodology can help in the constitution of realistic dataset with large variety of motion to support the development of a dedicated non-rigid registration model by deep learning.
Application of Multiecho Dixon Technique and IVIM-DWI in Patients with Primary Osteoporosis : A Preliminary Study with 3.0 T MRI
Authors: ju fan qiu , hui tan , nan yu , yu wang shao
Published: August 2024

Bone mineral density (BMD) is a common standard for evaluating osteoporosis, but it can only reflect the change of bone mass, not the microscopic nodules of tissueChange of structure. Multi-echo Dixon and IVIM-DWI were used to evaluate the changes of spinal bone marrow microstructure in osteoporosis, osteopenia and normal subjects. The results showed that there were significant differences in FF, D and D* between osteoporosis, osteopenia and normal subjects. These results indicate that IVIM-DWI can quantitatively reflect the changes of lumbar microcirculation and fat content, and can be used as a biomarker for the progression of osteoporosis.
State of Art, Powerful, System On Chip, Design,Development and Implementation of Multi Channel Transceiver for MRI Spectrometer
Authors: Harsh Rajesh , Verma Dharmesh , Raut Aparna , Dipnaik Mahadev
Published: August 2024

The increasing complexity of modern MRI hardware design makes system challenging. MRI systems equipped with multi-channel exciter and multi-channel data-acquisition modules, particularly high-channel-counts often requires a huge cost. This abstract summaries the design and development of a low cost, small form factor, system on chip approach to realize a complete 1.5 T MRI spectrometer on a small chip of 28 nanometer fabric. The developed system executes parallel image processing algorithms and compatible instrumentation for accurate spatial and temporal requirements.
A High Performance Gradient and RF Insert for Dental MRI
Authors: Amrein Philipp , Ilbey Serhat , Littin Sebastian , Jia Feng , Bock Michael , Zaitsev Maxim , Özen Ali
Published: August 2024

Dental MRI requires high resolution imaging, e.g., for detection of root canals, as well as, high readout bandwidth for short T2* tissues, such as dentin and nerve fibers. These requirements can only be satisfied by high-performance gradients. In this study, we show with Bloch simulations the necessity for high performance gradients, and consequently introduce a gradient and RF insert, which is optimized for dental MRI. We also explore the concept a cylindrical encoding for curved slices for 4-fold acceleration compared to conventional encoding.