bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of Multi-modal MR Imaging for Glioma Based on a Deep Learning Reconstruction Approach with the Denoising Method
Authors: Sun Jun , Guo Yiding , Zhuo Zhizheng , Xu Siyao , Guo Min , Chai Li , Li Junjie , Qu Liying , Wu Minghao , Wei Juan , Li Mingna , Li Tong , Weng Jinyuan , Gong Xiaodong , Duan Yunyun , Zhou Dabiao , Liu Yaou
Published: August 2024

Deep learning reconstruction (DLR) approach with denoising can improve image quality of magnetic resonance (MR) images. However, its applications on multi-modal glioma imaging have not been assessed. Multi-modal images of 107 glioma patients were evaluated by signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), edge sharpness, visual assessment, diagnosis accuracy and efficiency. Contrasted with conventionally reconstructed images, the DLR images showed higher tumor/residual tumor SNR, higher tumor to white/gray matter CNR, better results of the visual assessment, and a trend of improved diagnosis efficiency and comparable accuracy. DLR can improve image quality of multi-modal glioma images which should benefit the glioma diagnosis.
A multiparametric protocol to investigate the effects of physical activity on lumbar spine muscles
Authors: Maggioni Marta , Sibgatulin Renat , Krämer Martin , Güllmar Daniel , Reichenbach Jürgen
Published: August 2024

It is well established in literature that MRI quantitative parameters such as T2 or diffusion coefficients change significantly immediately after a strenuous exercise session. In this work, we instead focus on the long-term effects of regular repeated physical activity on three cohorts characterized by different training regimes. A multiparametric protocol was developed to assess T1, T2, fat fraction, and IVIM diffusion values to examine differences in lumbar spine muscle physiology between the different cohorts.
Impacts of Longitudinal Coil Encoding on Simultaneous Multi-Slice (SMS) Head MRI
Authors: Duan Yunsuo , Liu Feng , Marsh Rachel , Riddle Mathhew , Patel Gaurav , Kangarlu Alayar , Kegeles Lawrence , Vaughan John
Published: August 2024

Coil encoding in the longitudinal direction (z-direction) plays an important role in SMS MRI quality. Although many head coil arrays have been reported, systematic research on impacts of coil encoding in the longitudinal direction on SMS imaging remains insufficient. We present a comparison study of coil encoding for head arrays. Our experimental results showed that, to achieve quality images, the mulitband factor should be equal to or less than the number of coil rows. In extreme cases, the mulitband factor should not exceed 1.5 times the number of coil rows.
Performance and B1 Efficiency Analysis of Different Dipole Antenna Types at 7T.
Authors: Bhosale Aditya , Zhang Xiaoliang
Published: August 2024

In this work, we compare the performance of several dipole antenna types for MR applications at 7T in terms of quality factor, B1+ strength, SAR, B1+ field pattern, and B1+ efficiency. This study may provide guidance on the selection of an appropriate dipole coil for a specific imaging application.
Simulations of an integrated RF/wireless neonatal head coil array for multiple-input multiple-output (MIMO) wireless MRI data transmission
Authors: Dickinson Olivia , Taracila Victor , Overson Devon , Lynch Spencer , Reed Beth , Robb Fraser , Song Allen , Truong Trong-Kha , Darnell Dean
Published: August 2024

Neonatal neuroimaging can be significantly improved using a form-fitting, lightweight coil array that is untethered from the scanner for a high SNR and reduced setup time. An iRFW coil array does this by performing simultaneous RF signal acquisition and wireless data transfer with the same coil element. Proof-of-concept simulations of a form-fitting soccer-ball geometry 16-channel iRFW coil head array show a high and uniform SNR in the neonatal head and WIFI 6 antenna gain patterns that radiate power outside the bore using a 2x1 multiple-input multiple-output WIFI 6 scheme for the high data rate wireless transmission of MRI data.
Metabolic Imaging of Pancreatic Ductal Adenocarcinoma
Authors: Yousf Saleem , Glunde Kristine , Brown Dalton , Tressler Caitlin , Goggins Michael , Bhujwalla Zaver
Published: August 2024

Metabolic imaging techniques such as mass spectrometry imaging (MSI) complement magnetic resonance spectroscopy and colocalize metabolite profiles with immunohistological evaluation of tissue sections. Here we have performed matrix-assisted laser desorption/ionization (MALDI)-MSI of normal pancreatic tissue, intraductal papillary mucinous neoplasm (IPMN), and pancreatic ductal adenocarcinoma (PDAC) to characterize the spatial distribution of PDAC metabolites in tissue sections. Our preliminary data with MALDI-MSI identifies significantly increased taurine and significantly decreased creatine, both of which can also be detected with 1H MRS, in PDAC compared to normal tissue. The spatial heterogeneity of metabolite distribution in PDAC tissue can be related to immunohistochemical evaluation.
Comparison of integrated slice-specific dynamic shimming and echo-planar imaging diffusion-weighted imaging in bladder cancer detection and characterization
Authors: zhao yujiao , you cong , zhang cheng , qu feifei , zhu jinxia , Benkert Thomas
Published: August 2024

This study investigated the image quality and lesion characterization of bladder lesions on integrated slice-specific dynamic shimming (iShim) diffusion-weighted imaging (DWI) compared with single-shot echo-planar imaging (ss-EPI) DWI. The qualitative and quantitative image quality analyses were compared between the 2 DWI techniques. The diagnostic agreements of lesion characterization, including submucosal stalk and myometrial invasion, were also evaluated on DWI images compared with pathologic results. The results indicated that iShim-DWI provided better bladder tumor detection and image quality than ss-EPI DWI, suggesting that iShim-DWI might serve as a competent technique in bladder imaging.
Opportunities for improved myocardial first-pass perfusion imaging at 0.55T
Authors: Tian Ye , Cui Sophia , Garg Parveen , Nayak Krishna
Published: August 2024

Myocardial first-pass perfusion (FPP) MRI is used in the clinic to diagnose coronary artery disease but has limited spatial resolution and coverage. Contemporary low-field scanners have the potential to provide FPP imaging with improved resolution and coverage by leveraging different acquisitions, such as spiral bSSFP. In this study, we demonstrate a time-efficient spiral bSSFP FPP pulse sequence at 0.55T and compare it with the standard Cartesian FPP in 4 healthy volunteers. Measured SNR, CNR, and myocardial boundary sharpness scores are all higher in the spiral images than in Cartesian images.
Applying diffusion signal representation further than DTI improves cardiac dMRI insights
Authors: Rodríguez-Galván Justino , Merino-Caviedes Susana , Filgueiras-Rama David , Sánchez-González Javier , Tristán-Vega Antonio , Alberola-López Carlos
Published: August 2024

Diffusion MRI in the brain has undergone tremendous advances in the last two decades while cardiac and general diffusion in the body show a lower speed. As for modelling, either isotropic or diffusion tensor imaging (DTI) are, by far, the methods used outside the brain. In this abstract we intend to quantify the better modeling capabilities of higher order (HO) methods than DTI, i.e., than Gaussian distributions. We show, by means of ex-vivo diffusion in pig hearts, that non-Gaussianity is observable and that diffusion weighted images (DWI) generated out of a HO model show more closeness to reality than DTI.
Low-dose Dobutamine Stress CMR perfusion for the Evaluation of Myocardial Microcirculation Induced by Chronic High-Altitude Hypoxia in Rats
Authors: He Bo
Published: August 2024

This study investigated the cardiovascular effects of altitude exposure, and determined the feasibility of stress first-pass perfusion CMR to objectively and noninvasively diagnose chronic HAH-induced microvascular changes. The results showed a significant decreased in LVEF as compared with NC animals at two time points. Our study has shown rest_RU and stress_RU were significantly lower and rest_MPI, stress_MPI and MPR were significantly higher. The pilot testing demonstrated that the feasibility of stress first-pass perfusion CMR to objectively and noninvasively diagnose chronic HAH-induced microvascular changes.
Characterization of Cardiac Quantitative Susceptibility Mapping (QSM)
Authors: Tyler Andrew , Huang Li , Neji Radhouene , Mooiweer Ronald , Masci Pier-Giorgio , Roujol Sébastien
Published: August 2024

Cardiac Quantitative Susceptibility Mapping (QSM) is a promising technique for the evaluation of iron levels in the myocardium, particularly after a hemorrhagic infarction. In this abstract, we validate the accuracy of our QSM acquisition and reconstruction procedure in phantom experiments, and characterize its precision and repeatability in the myocardium in a healthy volunteer cohort. We found a strong linear relationship between the gadolinium concentration and measured susceptibility in the phantom. In vivo QSM precision and repeatability in the myocardium were 0.11±0.05 ppm and 0.02±0.02 ppm, respectively.
Global, segmental and layer specific analysis of myocardial involvement in Duchenne muscular dystrophy by LGE
Authors: Fang Xuelin , Sun Longwei , Luo Yizhen , Liang Guohua , Yang Liqi , Deng Kan , Li Zhiyong
Published: August 2024

To provide more imaging basis for early identification and prognosis evaluation of DMD-associated cardiomyopathy(DMD-CM), we analyzed the distribution characteristics of LGE in global and regional left ventricle and the correlation between myocardial fibrosis index and cardiac function indexes in 29 boys with DMD. The range of LGE and the distribution pattern of interventricular septal involvement are related to the decrease of cardiac function. LGE is a reliable tool to identify subclinical DMD-CM and evaluate the severity of the disease.
High Resolution In Vivo Diffusion Tensor Distribution MRI of the Whole Human Brain with 300 mT/m Gradients
Authors: Magdoom Kulam Najmudeen , Avram Alexandru , Gasbarra Dario , Witzel Thomas , Huang Susie , Basser Peter
Published: August 2024

Whole brain DTD MRI was performed at 1.2 mm isotropic resolution in-vivo using 300 mT/m gradients. An efficient and easy to implement interfused-PFG (iPFG) sequence was used to acquire multiple diffusion encoded images. Size, shape and orientation heterogeneity are measured and mapped from the estimated DTD along with a new form of tractography. The results show varying heterogeneity in different areas of the cerebral cortex, and subcortical and white matter regions. DTD tractography captured complex fiber configurations absent in DTI tractography.
NODDI-based identification of white matter tracts in regions of peritumoral edema: a validation study in brains bearing meningioma tumors.
Authors: Hakhu Sasha , VanGilder Jennapher , Paulson Lucas , Hu Leland , Zhou Yuxiang , Schilling Kurt , Beeman Scott
Published: August 2024

White matter (WM) tract detection proximal to brain tumors, surrounded by vasogenic edema during tumor resection is critical. Previous work has shown that NODDI presents a more accurate quantification of WM in edema as compared to DTI. However, these studies included gliomas and metastases, which are known to infiltrate WM. Here, we focus on validating the use of the NODDI model for WM identification in edema only in non-invasive meningiomas. Our results showed that DTI-derived FA of WM near edematous regions were lower than contralateral WM in non-edematous regions; in contrast, NODDI-derived ODI values for the same regions remained comparable.
Improving temporal resolution in dynamic hyperpolarized 13C spiral chemical shift imaging using low rank plus local sparse reconstruction
Authors: Zhu Minjie , Mayer Dirk , Jhajharia Aditya , Rogers Joshua
Published: August 2024

Improve the accuracy of under-sampled dynamic images for lower intensity metabolites with low rank and local sparsity reconstruction
MRI compatibility study of a brain PET insert integrated with a quadrature birdcage transmit /47-channel receiver head coil assembly at 3 T
Authors: Chen Qiaoyan , Kuang Zhonghua , Yang Yongfeng , Tie Changjun , Zhang Xiaoliang , Liu Xin , Zheng Hairong , Li Ye
Published: August 2024

Simultaneous positron emission tomography/magnetic resonance imaging (PET/MRI) shows advantages in clinical and research applications for human brain. In this work, MRI compatibility of a brain PET insert integrated with a quadrature birdcage transmit /47-channel receiver head coil assembly was studied. The results of RF field (B1+) distribution, signal-to-noise ratio (SNR) and static field inhomogeneity (ΔB0) show MRI compatibility of the brain PET insert. Simultaneous PET/MRI was implemented, which demonstrated a high performance of the brain PET/MRI system.
Design of a universal RF-shimming drive mode for head and neck imaging at 7 Tesla using a 16-channel pTx array
Authors: Kazemivalipour Ehsan , May Markus , Rangaprakash D. , Bilgic Berkin , Stockmann Jason , Barry Robert , Keil Boris , Wald Lawrence , Guerin Bastien
Published: August 2024

We calculate “universal” RF-shimming excitations that provide maximum B1+ coverage and homogeneity across the brain & c-spine using a patient-friendly 16-channel pTx array. We simulated three body models and three z-positions to ensure robustness to both B1+ and SAR variation across a range of head/neck sizes and shapes (universal design). We provide two solutions, both of which may be saved on the scanner: a low-SAR solution that improves flip-angle uniformity by 13% compared to the BC mode excitation (same SAR) and a high-SAR excitation that improves flip-angle non-uniformity by 25% at the cost of a 2x local SAR increase.
Self-Grounded Bow-Tie Antennas Placed Perpendicular to B0 in a Helmet RF Array Improve B1+ Uniformity for Brain MRI at 7.0T
Authors: Rahimi Faezeh , Eigentler Thomas , Nurzed Bilguun , Millward Jason , Niendorf Thoralf
Published: August 2024

UHF-MR uses RF arrays to shape the magnetic field generated inside the brain. For brain MRI at 7T, a helmet shaped transmit RF array could be beneficial versus conventional annular configurations. Recognizing this opportunity this work examines the feasibility of a multi-channel TX helmet RF applicator using broadband Self-Grounded Bow-Tie (bbSGBT) antenna building blocks. The focus is on enhancing B1+ uniformity and coverage for brain MRI at 7.0T. Our findings obtained for the human head voxel model Duke demonstrate improved mean B1+ coverage and increased B1+ uniformity for the helmet configuration.
Comparison of universal phase shims determined from simulated and measured B1+ maps in the prostate and heart at 7T
Authors: Wildenberg Saskia , Egger Nico , Nagelstraßer Sophia , Kimmlingen Ralph , Lanz Titus , Nagel Armin M. , Bitz Andreas K.
Published: August 2024

Universal RF shimming is a proven method to avoid the time-consuming process of calculating patient-specific RF shims for every individual subject. Nevertheless, this method requires numerous B1+ maps from in vivo measurements, which is a time-consuming process, especially in the context of product development. This work therefore investigates whether a universal RF shim based on simulated B1+ maps, which are needed for the safety assessment of the coil anyways, is a viable alternative compared to shim optimization based on in vivo data. The study was performed using a torso coil at 7T for the prostate and cardiac region.
A 16-channel MC and RF hybrid system for B0 shimming and B1 reception: a preliminary prototype
Authors: Ianniello Carlotta , Theilenberg Sebastian , Majumder Jonah , Vaughan John , Juchem Christoph
Published: August 2024

We explore the potential of a hybrid approach in which RF receive elements are driven with direct current for B0 shimming (RF+MC) aided with multicoil shim-only elements (MC-only) to overcome the challenging B0 inhomogeneities in the frontal brain. A proof-of-concept implementation consisting of 16 RF+MC elements and 18 MC-only elements is presented. Simulations have shown minimal SNR loss despite the proximity of MC-only elements. Furthermore, the B0 shimming performance of this preliminary setup outperformed 3rd and 5th order SH shimming despite its rudimentary design. Future work will focus on optimizing the B0 performance while minimizing the MC-to-RF coupling.
GIRF-based characterization of a novel cryogen-free HTS magnet
Authors: Roeloffs Volkert , Hömmen Peter , Voß Andreas , Li Yi , Odenbach Robert , Bartsch Leander , Lother Steffen , Röll Stefan
Published: August 2024

We characterized our new 1.5 T HTS magnet via GIRF determination. Analysis of time scales showed that relevant first-order eddy currents exhibit time constant of less then 200 µs. This finding is a promising characterization of our system but requires further investigations.
Intravoxel Incoherent Motion Diffusion Weighted MR Imaging to Evaluate Myocardial Microvascular Dysfunction of Exertional Heat Illness
Authors: Jun Zhang , Song Luo , Weiqiang Dou
Published: August 2024

Purpose: To investigate the feasibility of assessing myocardial microvascular perfusion of patients with exertional heat illness (EHI) by intravoxel incoherent motion imaging. Methods: CMR-IVIM image quality was evaluated with a 3-point scale. CMR-IVIM derived parameters were analyzed and compared between EHI and HC. Receiver operating characteristic curve was used. Results: CMR-IVIM image quality were significantly improved. EHI patients showed decreased D*, decreased f values and higher D values compared to HC. f showed the most robust efficacy for detecting EHI related myocardial injury with the highest area under the curve. Conclusion: CMR-IVIM can evaluate myocardial injury of EHI patients.
RECOMPOSE – Reproducing DECOMPOSE Using Susceptibility Maps Acquired for Clinical Research
Authors: Fuchs Patrick , Chen Jingjia , Kiersnowski Oliver , Murdoch Russell , Liu Chunlei , Shmueli Karin
Published: August 2024

Here, we reproduced the results of the DECOMPOSE susceptibility separation model using new $$$T_2^*$$$-weighted data independently acquired using three clinically applicable sequences and processed with different QSM pipelines. This allowed us to investigate the sensitivity of DECOMPOSE to various dipole inversion algorithms. Good susceptibility source separation results were achieved using a 5-echo GRE acquisition, but maps of diamagnetic and paramagnetic sources from a highly accelerated 5-echo EPI sequence were noisy. When the input susceptibility maps exhibited artefacts, these were exacerbated by DECOMPOSE. Care must be taken not to lose local structural information when using (highly) regularised input susceptibility maps.
Exploring the oscillating gradient waveform frequency dependence of diffusivity changes in human acute ischemic stroke
Authors: Zhou Mi , Stobbe Robert , Buck Brian , Kate Mahesh , Fairall Paige , Emery Derek , Feiweier Thorsten , Beaulieu Christian
Published: August 2024

Two previous oscillating-gradient-spin-echo (OGSE) studies of human acute ischemic stroke using different diffusion waveforms (40 Hz, one-period; 50 Hz, two-period) have reported considerably different mean diffusivity (MD) changes in lesion white matter relative to long diffusion time (“0 Hz”) pulsed-gradient-spin-echo (PGSE). Here both OGSE waveforms were acquired in 8 stroke patients. Lesions showed marked diffusion time dependencies with lesion MD reduction of 40% for PGSE compared to 25% for OGSE 40Hz, and yet OGSE 50Hz was only a bit less (21%). Large heterogeneity between patients (+6% to -43% of OGSE 50Hz MD lesion changes) may explain earlier study differences.
Application of Artificial Intelligence (AI)-assisted compressed sensing technology in ankle joint
Authors: Wang Nan , Song Qingwei , Liu Ailian , Li Guobin , Zhang Shuheng , Zhang Yunfei , Dai Yongming
Published: August 2024

ACS combines CS, half Fourier HF and parallel imaging (PI), and introduces deep learning neural network as AI module into the reconstruction process. Millions of fully sampled data are used to train AI models, so as to suppress various reconstruction artifacts introduced by traditional acceleration methods under high acceleration factors without affecting anatomy and pathological structures. ACS is used for noise suppression, artifact reduction and information recovery. ACS can effectively correct any major errors of single acceleration methods, thus providing a higher acceleration level for MRI imaging.
Feasibility of high-frequency shear wave MR elastography of the parotid glands
Authors: Atamaniuk Vitaliy , Chen Jun , Glaser Kevin , Pozaruk Andrii , Obrzut Marzanna , Obrzut Bogdan , Domka Wojciech , Gutkowski Krzysztof , Ehman Richard , Cholewa Marian
Published: August 2024

A specialized driver was developed to enable magnetic resonance elastography of the parotid and other salivary glands using high shear wave frequencies to provide improved spatial resolution and optimized ergonomics. The performance of this new device was tested in volunteer studies. Preliminary results showed that suitable shear wave illumination of the parotid gland is possible at frequencies as high as 120 Hz and that high-frequency shear wave MR elastography of the parotid gland is feasible.
RF pulse optimization for robust excitation in 31P magnetization transfer spectroscopy
Authors: Graf Christina , Diwoky Clemens , Rund Armin , Stollberger Rudolf
Published: August 2024

In this work, robust excitation pulses for 31P spectroscopy at 7T are designed by optimal control. The particular challenges of inhomogeneous RF field due to use of surface RF coils and broad bandwidth requirements due to the nature of 31P were addressed thoroughly. The optimized RF pulses show superior performance compared to adiabatic RF pulses during numerical simulations and phantom experiments. Application of the optimized RF pulses to T1 prediction by dual angle method is the logical consequence.
Vector concomitant field mapping by phase contrast imaging
Authors: Lee Seung-Kyun , Ajala Afis
Published: August 2024

We show that concomitant field-induced phase in phase-contrast imaging allows measurement of the transverse (x,y) components of the magnetic field generated by a gradient coil. Combined with conventional B0 mapping which gives the z-component, the method permits experimental determination of the full three-dimensional vector magnetic field of a gradient coil. We demonstrate the method on a high-performance head gradient (MAGNUS) system and discuss its application to concomitant-field artifact correction based on one-time calibration.
Simulation and Comparison of Transmit Elements for 7T Head-Imaging with a Large Diameter Transmit Coil
Authors: Hubmann Max Joris , Kowal Robert , Orzada Stephan , Wagner Piet , Seifert Frank , Speck Oliver , Maune Holger
Published: August 2024

12 transmission coil designs for 7T head imaging are compared using EM simulations for a large diameter transmit coil. The highest power and SAR efficiency are achieved by loop coils, a passively-fed dipole shows the highest intrinsic decoupling and an IMARS the lowest load dependence. The results provide insight to each element's performance. To make a final decision on a coil element, the array performance must also be evaluated in the futur, as this may differ from the performance of the single element performance. Thus, the decision on a particular transmit element depends on the coil's application and configuration.
16-Channel 11.7T Transmit Array with Integrated Field Probes
Authors: Chu Son , Gras Vincent , Boulant Nicolas , Gunamony Shajan
Published: August 2024

Transmit arrays are essential to mitigate B1+ inhomogeneity at extremely high static magnetic field strengths. In addition, the transmit elements must be arranged in multiple rows to achieve whole-brain coverage at 11.7T. Furthermore, concurrent field monitoring probes offer the possibility to improve MR image quality by correcting subject-specific k-space trajectories and monitoring real-time dynamic field fluctuations. The placement of these probes must be carefully controlled to achieve proper probe conditioning as well as to preserve the RF performance of the transmit array. This work presents the numerical simulation and optimization of a 16-channel-transmit array with integrated field probes.
Simultaneous numerical modeling of 13C-MRI enzyme kinetics, diffusion effects, and RF refocusing
Authors: Dingwell Dylan , Cunningham Charles
Published: August 2024

In this study, we used a particle-based Brownian dynamics simulator with concurrent MR modeling to characterize diffusion-related effects on 13C signal dynamics. We conducted a spectrophotometric lactate dehydrogenase (LDH) activity assay with and without the presence of glass beads to measure the influence of diffusion constraints and spatial compartmentalization on the reaction kinetics of LDH-mediated conversion of pyruvate to lactate. We also investigated the relationship between diffusion and RF refocusing in a typical fast GRE sequence by comparing simulated signal intensities for RF spoiled and non-spoiled GRE sequences applied under varying diffusion conditions.
Accelerated MRI using intelligent protocolling and subject-specific denoising
Authors: Ravi Keerthi Sravan , Nandakumar Gautham , Thomas Nikita , Lim Mason , Qian Enlin , Jimeno Marina Manso , Poojar Pavan , Jin Zhezhen , Quarterman Patrick , Fung Maggie , Srinivasan Girish , Vaughan John Thomas , Geethanath Sairam
Published: August 2024

The routine brain screen protocol employed at our institution was accelerated using Look Up Tables to achieve a 1.94x gain in imaging throughput. Image-denoising was performed on accelerated data by leveraging deep learning models trained on contrast-specific publicly available datasets. These were corrupted by native noise during forward modeling. In addition, subject-specific denoising was demonstrated. The superior performance of denoised data on automated volumetry of Alzheimer’s Disease (AD) relevant brain anatomies on T1w data demonstrated potential for accelerated AD imaging.
MRI of the diaphragm: characterizing motion and microstructural properties in ICU patients
Authors: Wennen Myrte , Marcus Tim , Jonkman Annemijn , Meijboom Lilian , Kachelriess Marc , Berker Yannick , Strijkers Gustav , Ottenheijm Coen , Heunks Leo , Nederveen Aart , Gurney-Champion Oliver
Published: August 2024

Diaphragm weakness is common in intensive care patients and has a detrimental effect on clinical outcome. Weakness in these patients may be explained by disuse atrophy or injury resulting from systemic inflammation among other factors. MRI can be used to study the motion and tissue characteristics of the diaphragm. We present the design of an MRI protocol for quantifying motion and tissue characteristics of the diaphragm. 4D MRI, relaxometry and dynamic contrast enhanced MRI were successfully applied in healthy volunteers and COVID-19 patients. Our method may aid in finding treatments and prevention strategies for diaphragm weakness in critically ill patients.
Functional Pulmonary Proton MRI: Voxel-wise Linear-fitting Ventilation (VOLVE) Assessment in Chronic Obstructive Pulmonary Disease (COPD)
Authors: Peggs Zachary , Brooke Jonathan , Paul Jan , Bradley Christopher , Cooper Andrew , Bolton Charlotte , Hall Ian , Francis Susan , Gowland Penny
Published: August 2024

The VOLVE (VOxel-wise Linear fit VEntilation, VOLVE) method, whereby voxel-wise linear fitting between the lung-diaphragm navigator signal and lung parenchyma MR signal is used to assess regional ventilation, was investigated in chronic obstructive pulmonary disease (COPD) and alpha-1 antitrypsin deficiency (A1ATD). Fractional ventilation (FV) maps derived from phase-resolved functional lung imaging (PREFUL) were also determined. Significant differences between the healthy and the lung disease groups were found, indicating the sensitivity of these techniques to emphysematous lung disease.
Effect of Kaftrio therapy on pulmonary ventilation derived by 3D phase-resolved functional lung MRI in cystic fibrosis patients
Authors: Klimeš Filip , Voskrebenzev Andreas , Gutberlet Marcel , Speth Milan , Grimm Robert , Dohna Martha , Hansen Gesine , Wacker Frank , Renz Diane , Dittrich Anna-Maria , Vogel-Claussen Jens
Published: August 2024

Kaftrio therapy was shown to improve global clinical ventilation parameters in cystic fibrosis (CF) patients. 3D phase-resolved functional lung (PREFUL) MRI offers a contrast-free assessment of pulmonary ventilation during free breathing. The aim of this study was to determine whether 3D PREFUL parameters are suitable to measure response to Kaftrio therapy and their association with clinical outcomes in CF patients. All assessed MRI and clinical parameters significantly improved after initiation of Kaftrio. Relative change between baseline and post-treatment scans of 3D PREFUL ventilation defect percentage maps was in agreement with forced expiratory volume in 1 second and lung clearance index.
Cine T2 mapping reveals cardiac cycle-dependent T2 variability in cardiomyopathy
Authors: Nagao Michinobu , Yoneyama Masami , Goto Yasuhiro , Shiina Isao , Kodaira Kazuo , Kato Mana , Katsumata Yasutomo , Shirai Yurie , Yamamoto Atsushi , Sakai Akiko , Nakao Risako , Sakai Shuji
Published: August 2024

We have successfully developed cardiac cine imaging to project T2 values using T2prep-based T2 mapping with dynamic multiple trigger-delay framework. We have demonstrated that diastolic T2 values on cine T2 mapping are temporarily prolonged in patients with non-ischemic cardiomyopathy and impaired left ventricular function. Cine T2 mapping is a new noninvasive in vivo imaging technique for myocardial edema that provides an effective means of elucidating the pathogenesis of cardiomyopathy.
From Survival to Survivorship: Cardiac MRI and Serum Biomarkers of Early Detection and Therapy for Doxorubicin-Induced Cardiotoxicity in Mice
Authors: Stapleton Margaret , Mazzella Elizabeth , Coulson Noah , Cater George , Schwabb Kristina , Hartwick Sean , Becker-Szurszewski Thomas , Cortes Devin , Wu Yijen
Published: August 2024

Anthracycline, like Doxorubicin (DOX), induced cardiotoxicity is a major cause of morbidity among childhood cancer survivors. Prior clinical studies diagnose using isolated measures of cardiac function, but by the time cardiotoxicity is detected, irreversible damage has already occurred. We hypothesize that multi-parametric cardiac MRI (CMR), and concurrent treatment with cardioprotective agents is a more sensitive biomarker for early diagnosis of DOX-induced cardiotoxicity. We identified DOX cardiotoxicity by CMR derived LV strain and Luminex biomarker analysis prior to any decrease in EF and SV. Our study suggests multi-parametric CMR with concurrent cardioprotective treatment can be a surrogate endpoint for therapeutic efficacy.
Anatomy and Image Contrast Metadata Verification using Self-supervised Pretraining
Authors: Duffy Ben , Chamberlain Ryan
Published: August 2024

Automated metadata verification is essential for data quality checking. This study evaluates the extent to which self-supervised pretraining can improve performance on the anatomy and image contrast metadata verification tasks. On a small but diverse dataset, pretraining coupled with supervised finetuning, outperforms training from an ImageNet initialization, suggesting improved near out-of-distribution performance. On a larger brain-only dataset, training a linear classifier on the self-supervised pretrained network embeddings outperforms the corresponding ImageNet pretraining or random initialization on the image contrast prediction task. Cross-checking predictions against the DICOM metadata was an effective method for detecting artifacts and other quality issues.
Using machine learning to evaluate values of six diffusion models to predict the efficacy of neoadjuvant chemotherapy for esophageal cancer
Authors: Cui Long , Bai Bingmei , Wang Chenglong , Song Yang , Li Shengyong , Wang Haijie , Qu Jinrong , Yang Guang
Published: August 2024

We assessed the performance of diffusion models for assessing response to neoadjuvant chemotherapy (NACT) using machine learning. Firstly, features were extracted from the region of interest on different parametric maps of different diffusion models for esophageal squamous cell carcinoma (ESCC) patients and changes of the parameters (Δ parameter) before and after NACT (pre-NACT and post-NACT) were calculated. Then different Δ-NACT models and pre-NACT models were built for using features from different diffusion models. The results demonstrated that diffusion models may be used to predict the efficacy of NACT in ESCC patients.
Altered cerebellar GABA-mediated cerebral functional networks in patients with schizophrenia: A transcranial magnetic stimulation study
Authors: Yao Chenyang , Zhao Youjin , Ai Kai , Zhang Bo , Su Lui
Published: August 2024

To investigate the cerebellar GABA-mediated cerebral functional networks, we measured cerebellar basal and stimulus-activated GABA content in schizophrenia patients (SCZ) and healthy controls (HC) with cerebellar transcranial magnetic stimulation (TMS). We utilized graph theory to calculate global and regional property changes of cerebral functional networks and their correlations with cerebellar GABA at baseline and after TMS. The results show significant increase of the global efficiency, nodal clustering coefficient of left ventral attention network (VAN) after TMS in SCZ. This provides new molecular evidence for neuropathology of cerebellum dysfunction in SCZ and reveal potential interaction with cerebral functional networks.
Neuromelanin Imaging at 0.5T Reveals Elongated T1 in Neuromelanin-Rich Brain Regions In Vivo
Authors: Stainsby Jeff , Curtis Andrew , Chavez Sofia , Harris Chad
Published: August 2024

Mid-field imaging benefits from increased T1 tissue differentiation and reduced SAR constraints for generating MT contrast. These were leveraged in imaging of neuromelanin containing structures at 0.5T. Elevated T1 values in the substantia nigra and locus coeruleus were demonstrated. Contrary to T1-weighted approaches reported in the literature a proton density weighted fast spin echo approach is shown to provide improved visualization at mid-field and implies modified strategies at higher field would be beneficial.
Accuracy of Deep Learning-based Signal-to-noise Measurements using Air Recon DL
Authors: McNabb Evan , Fortier Véronique , Levesque Ives
Published: August 2024

Noise estimates in Deep Learning-based image reconstruction (DLR) from background regions lead to artificially low noise estimates and thus inaccurate SNR. Noise estimate accuracy was improved using the difference between two identical acquisitions. SNR increased in DLR compared to standard reconstruction in clinical sequences over a range of acquired signal averages and voxel sizes. With DLR, varying signal averages had little effect on the measured SNR in fast spin echo acquisitions, while SNR increased by more than three-fold in single-shot fast spin echo. However, with DLR, SNR no longer follows predicable behavior, therefore sequence optimizations need to be performed experimentally.
CS-MRI Reconstruction Using an Improved Generative Adversarial Network with Channel Attention Mechanism
Authors: Li Xia , Zhang Hui , Li Tie-Qiang
Published: August 2024

Generative adversarial network (GAN) has emerged as one of the most prominent approaches for fast CS-MRI reconstruction. However, most deep-learning models achieve performance by increasing the depth and width of the networks, leading to prolonged reconstruction time and difficulty to train. We have developed an improved GAN-based model to achieve quality performance without increasing complexity by implementing the following: 1) dilated-residual structure with different dilation rates at different depth of the networks; 2) CAM to adjust the allocation of network resources; 3) multi-scale information fusion module to achieve feature fusion. Experiment data have confirmed the validity for the modules.
Clinical Viability of AI-enabled 0.5T MRI Scanner to Improve Access
Authors: Narula Arjun , Patil Uday , SH Anand , Raveendran Harikrishnan , Muniraj Shailaja , Rao Pallavi , Menon Anurita , Garza Allison , Kumar Santosh , Kumar Gautam , NR Srinivas , Babu Syam , Jaiswal Ravi , Sundaresan Rajagopalan , Reddy Ashok , Rajamani Sajith , Das Rajdeep , Jain Nitin , Ramanna Sudhir , Sundar  , Charlaas Florintina , Chatterjee Sudhanya , Patil Rohan , Goel Megha , Shanbhag Dattesh , Anand Vikas , Galagali Abhishek , KV Sathish , Shankpal Preetham , Agarwal Harsh , Joel Suresh , Venkatesan Ramesh
Published: August 2024

We validate the clinical viability of a 0.5T scanner to reduce cost and improve access to quality MRI using AI based IQ enhancement to compensate for IQ reduction due to lower field and other lower hardware specifications. We obtained data from 65 patients from the re-ramped 0.5T and a commercially available 1.5T MRI system for brain and cervical spine. Radiologists compared image quality between the two and rated the image on the ability to perform diagnosis. We observed that more than 90% of the images were rated to be above diagnostic levels and AI reconstruction significantly improved the image quality.
Full-brain multi-pathway relaxometry using a golden-angle radial scheme and sparsely-sampled radial spokes
Authors: Shao Li-Ya , Wang Zih-Ci , Madore Bruno , Cheng Cheng-Chieh
Published: August 2024

Quantitative MRI is emerging as a powerful diagnostic tool for neuroimaging applications. A motion-robust, golden-angle radial acquisition version of the ‘triple-echo steady-state’ (TESS) relaxometry method was implemented here, to mitigate the artifacts induced by the flowing motion of the cerebrospinal fluid (CSF). To improve the scan efficiency, a probability density function-based sparse sampling scheme was introduced in each radial spoke. Close agreement was obtained between reference and TESS scans for both T1 and T2 values, using a multi-compartment phantom. In vivo whole-brain results were further obtained (3D T1 and T2 maps, 1-mm isotropic resolution, whole-brain coverage, 7.5-minute scan).
3D Free-Breathing Ultrashort Echo Time (UTE) 1H Ventilation Compared with Hyperpolarized 129Xe Ventilation
Authors: Tan Fei , Eddy Rachel , Diamond Vanessa , Rayment Jonathan , Larson Peder
Published: August 2024

This abstract compares the 3D UTE 1H ventilation calculated from Motion-Compensated Low-Rank constrained reconstruction (MoCoLoR) with the hyperpolarized 129Xe ventilation for validation. The dataset covers healthy volunteers and pediatric and adult patients with cystic fibrosis (CF). We validated that 3D UTE 1H has a positively correlated VDP with the gold standard 129Xe and a high spatial VDP accuracy.
Intravoxel incoherent motion and diffusion kurtosis imaging can be used to assess the differentiation degree of non-small cell lung cancer
Authors: Zheng Yu , Huang Wenjing , Zhang Jing , Han Na
Published: August 2024

The purpose of this study was to assess differentiation degree of non-small cell lung cancer (NSCLC) by using intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI). There were statistically significant differences in D and Dapp values between the poorly differentiated group and the moderately and highly differentiated group (p＞0.05). D value had the best diagnostic efficacy in evaluating the differentiation degree of NSCLC [area under the curve (AUC) =0.773]. Our study demonstrated that D value derived from IVIM and Dapp derived from DKI can distinguish the differentiation degree of NSCLC.
Ultrafast and versatile non-contract-enhanced MRA for visualization of whole-body dynamic blood flow using flow-sensitive CINE imaging
Authors: Shiina Isao , Nagao Michinobu , Yoneyama Masami , Katsumata Yasutomo , Kwon Jihun , Goto Yasuhiro , Hamatani Yutaka , Kodaira Kazuo , Ogawa Takumi , Kato Mana , Sakai Shuji
Published: August 2024

Flow-sensitive CINE imaging is non-contrast-enhanced MRA technique based on the Turbo Field Echo Planar Imaging (TFEPI). Because TFEPI is sensitive to blood flow, the MRA acquired with flow-sensitive CINE imaging includes dynamic flow information. In this study, we applied flow-sensitive CINE imaging to a variety of body parts such as trunk and lower extremity. Volunteer data demonstrated its usefulness to a variety of body parts. The combination of anatomical vascular pattern and the dynamic flow information may enable comprehensive assessment of whole-body arteries.
Imaging reactive oxygen species and tissue iron in ischemia-reperfusion injury in swine with multimodal [18F]ROStrace PET/CT and QSM
Authors: Swago Sophia , Thompson Elizabeth , Loth Annefleur , Bhattaru Abhijit , Moon Brianna , Ferrari Giovanni , Castillero Estibaliz , Ferrari Victor , Gorman Robert , Tschabrunn Cory , Mach Robert , Karp Joel , Witschey Walter , Bravo Paco
Published: August 2024

Additional myocardial injury can occur after reestablishing blood flow post ischemia. We use a multimodal protocol of sequential quantitative susceptibility mapping and positron emission tomography to directly image reactive oxygen species (ROS) and tissue iron in vivo in pig hearts after ischemic injury. We found that ROS was increased in infarct compared to remote regions of the myocardium in all animals. In an animal with microvascular obstruction, we observed an increase in susceptibility measured by QSM in the infarct region, indicating increased tissue iron, but no increased susceptibility was seen in the animals without microvascular obstruction.
Vasodilator Stress Myocardial Strain in Coronary Artery Disease：An Animal Study With Histological Validation
Authors: Xu Jing , Shihua Zhao , Lu Minjie
Published: August 2024

ATP can cause a pronounced positive inotropic effect on human heart. CMR-FT even at rest provides an excellent negative predictive value for myocardial ischemia and infarction in patients with CAD. CMR-FT is easy to perform without the need for dedicated acquisition and complex post-processing which can be applied to standard CMR cine sequences. Rest myocardial strain might be a noninvasive option serving as an additional gatekeeper for CAD patients with a needle-free test. Human studies are needed to validate these findings in a multicenter setting and to test whether CMR-FT can be incorporated into clinical guidelines.
The relationship of epicardial adipose tissue thickness with arrhythmias in patients with hypertension: a 3.0 T cardiac magnetic resonance study
Authors: Yang Zhaoxia , Tang Dazong , Luo Yi , Xiang Chunlin , Huang Lu , Xia Liming
Published: August 2024

Cardiac MRI enables quantification of EAT thickness with good to excellent reproducibility for differentiating the hypertensive patients with arrhythmias from those without arrhythmias and normal controls. Additionally, EAT thickness was correlated with native T1 and LVMi, which demonstrated EAT might induce cardiac remodeling and promote myocardial fibrosis. Cardiac MRI-derived EAT thickness metrics has great potential to further explore the mechanism of EAT with arrhythmias and guide an appropriate treatment in patients of hypertension.
The magnetic resonance characteristics of SPIONs for imaging at ultralow field (6.5 mT)
Authors: Shen Sheng , Waddington David , Zhang Marie , Rosen Matthew
Published: August 2024

Characterization of the parameters of superparamagnetic iron oxide nanoparticles (SPIONs) can guide synthesis of optimized particles for use in magnetic resonance imaging (MRI). With a goal of application of SPIONs in ultra-low field (ULF) MRI, we investigated the properties of SPIONs, and conducted imaging on a 6.5 mT MRI scanner. Specifically, we measured the NMR relaxivity and susceptibility of different SPIONs sample, both dominated by the core size of SPIONs. We also implemented susceptibility imaging using an bSSFP sequence to obtain positive contrast images of SPION phantoms, and present here a method to optimize the ULF susceptibility MRI images.
Repeatability of R1, R2* and fat fraction in Human Lumbar Vertebrae using a simultaneous multi-relaxation-time Imaging (TXI) method
Authors: Yang Jie , Feng Hao , Chen Meining , Yan Xu , Li Jianqi , Yi Yinqiao , Zhong Haodong , Zhong Jianquan
Published: August 2024

The quantitative MRI mapping techniques showed great potential in evaluating intervertebral disc degeneration (IVD) and diagnosing lower back pain. The repeatability of the quantitative methods is very important for clinical evaluation. A simultaneous multi-relaxation-time mapping (TXI) method was evaluated here, which can quantify the bone marrow fat fraction (BMFF), R2* and R1 value by a single scan and fast speed. The quantitative parameters of TXI showed high repeatability with high consistency and low CoVs, and could be applied in future clinical applications of IVD degeneration disease.
Whole Brain R2 Maps at 7T Highlight Iron-Rich Cortical Gray and Sub-cortical White Matter
Authors: Wang Yicun , van Gelderen Peter , de Zwart Jacco , Duyn Jeff
Published: August 2024

Gradient Echo Sampling of Spin Echo signal was used to obtain whole-brain R2 maps from 8 young and 1 senior healthy volunteers at 7T. Cortical surface reconstruction showed increased R2 in areas of high iron content as known from histology. Furthermore, high R2 in sensory-motor and visual cortices was accompanied by low R2 in underlying white matter. Highest R2 in subcortical white matter was found in frontal and temporal lobes. The low sensitivity of R2 to fiber orientation and venous vasculature may render it more suitable than R2* and $$$\chi$$$ for iron quantification, especially near the brain surface.
Deep Learning Based Real-time Quality Assessment of Pilot Tone Respiratory Signals
Authors: Tan Huixin , Huang Yantu
Published: August 2024

Pilot Tone (PT) respiratory signals are susceptible to interference like patient bulk motion or radio frequency interference. The signal curve is prone to bad when remains strong interference after suppression processing in the learning phase, resulting in low triggering accuracy and efficiency. With real-time quality assessment in the learning phase, a good-quality signal can be selected to learn better processing parameters. To ensure robustness and inference time, a tiny CNN is utilized to classify the signal into good and bad quality. Experimental results demonstrate that the proposed method has a strong ability to assess the quality of PT respiratory signals.
Efficient correction for MRI artifacts due to nonlinear variations in magnetic field using principal component analysis
Authors: Gendin Daniel , Liu Jiaen
Published: August 2024

Head motion can lead to artifacts in MR images. One source of motion artifacts is dynamic nonlinear variation in the background magnetic field (B0). Fully accounting for this variation is computationally intractable. We proposed an efficient method of performing this correction by making use of principal component analysis and considering only a few dominant modes. We applied our method to measured data and compared the results to the case with no correction as well correction using a previous K-means based method.
Feasibility study of a simulTaneous multi-relaXation-time Imaging (TXI) method in Intervertebral Disc
Authors: Yang Jie , liu Yujian , Hang Wenjia , Chen Meining , Li Jianqi , Yi Yinqiao , Zhong Haodong , Yan Xu
Published: August 2024

Quantitative imaging of intervertebral disc degeneration is important for the diagnosis of lower back pain. In our study, a simulTaneous multi-relaXation-time Imaging (TXI) method was evaluated, which generated bone marrow fat fraction (PDFF), R2* and R1 mapping within a single scan. The results showed that the BMFF, T2*, T1 mapping calculated from TXI method were close to the values reported in other studies for lumbar discs.