bluuebunny/crossref_metadata_2025 huggingface dataset:
Family of Novel Hyperpolarized 13C Molecular Imaging Probes Monitors Real-Time Oxidative Stress in Cancer Metabolism
Authors: Yamamoto Kazutoshi , Kondo Yohei , Opina Ana , Sail Deepak , Raju Natarajan , Blackman Burchelle , Malinowski Ronja , Seki Tomohiro , Kishimoto Shun , Oshima Nobu , Otowa Yasunori , Yamashita Kota , Crooks Daniel , Brender Jeffrey , Nonaka Hiroshi , Saito Yutaro , Choyke Peter , Ardenkjær-Larsen Jan H. , Mitchell James , Linehan W. Marston , Swenson Rolf , Sando Shinsuke , Krishna Murali
Published: August 2023

Molecular imaging can personalize cancer therapies by monitoring treatment responses, where hyperpolarized MRI is becoming an increasingly critical methodology. However, the limited number of available probes, which can interrogate key physiology/biochemistry related to targeted diseases, remains one of the major challenges in this growing field. In this presentation, we successfully demonstrate, for the first time, the advantages of newly synthesized 13C-Glutathione and 13C-N-acetyl cysteine probe in vivo redox status in a complementary manner. This approach serves as powerful non-invasive biomarkers to assess oxidative stress, which plays a vital role in various diseases and can be translatable to the clinical diagnosis.
Measuring Airflow Velocity in the Upper Airways with 129Xe Phase Contrast MRI: Feasibility in Pediatric Patients with Obstructive Sleep Apnea
Authors: Stewart Neil , Xiao Qiwei , Willmering Matthew , McConnell Keith , Wang Hui , Fleck Robert , Woods Jason , Amin Raouf , Bates Alister
Published: August 2023

We report preliminary HP 129Xe phase contrast (PC) MRI data in pediatric patients with obstructive sleep apnea; a common sleep-related breathing disorder caused by upper airway collapse. The feasibility and safety of 129Xe gas delivery through the patient’s anesthesia mask during tidal breathing under sedation (approximately sleep stage-2) was demonstrated. Dynamic spiral-based PC MRI (temporal resolution 0.5—1s) captured inspiratory and expiratory airflow, with sufficient sensitivity to identify flow features such as high-speed jets corresponding to regions of airway narrowing/obstruction on 1H anatomical MRI. With further data, our work may allow the development of optimized personalized treatment plans.
Measurement of cardiac magnetostimulation thresholds in pigs
Authors: Klein Valerie , Coll-Font Jaume , Vendramini Livia , Straney Donald , Davids Mathias , Ferris Natalie , Schad Lothar , Sosnovik David , Nguyen Christopher , Wald Lawrence , Guérin Bastien
Published: August 2023

We measured cardiac magnetostimulation thresholds in ten healthy pigs by discharging a 220-µF capacitor into a flat spiral coil placed close to the pigs’ torso. We used MR Dixon images to locate the porcine heart and determine the relative coil position to calculate the B-field in the heart (Biot-Savart). The average threshold for cardiac magnetostimulation during diastole was dB/dt≈1570±320 T/s at the center of the heart. This value is >10X greater than the IEC 60601-2-33 cardiac dB/dt limit for the effective stimulus duration of the magnetic stimulator system used in the experiments (0.45 ms).
Safety Assessment of Custom-Built Multi-Channel RF Coils: EM Modeling Uncertainties
Authors: Sadeghi-Tarakameh Alireza , Radder Jerahmie , Lagore Russell , Tavaf Nader , He Xiaoxuan , Grant Andrea , DelaBarre Lance , Vizioli Luca , Wu Xiaoping , Auerbach Edward , Moeller Steen , Adriany Gregor , Metzger Gregory , Van de Moortele Pierre‐Francois , Yacoub Essa , Ugurbil Kamil , Eryaman Yigitcan
Published: August 2023

Multichannel transmit (Tx) arrays are essential for ultra-high fields. In the absence of commercial options, such arrays must be built in-house. Prior to human imaging, however, safe operations limits for specific absorption rate (SAR) must be established. This is done using EM simulations, the accuracy of which has to be verified by comparing measured and simulated data. Unfortunately, EM simulations may not fully represent experimental conditions, especially for complex transmitter designs. In this work, we propose a numerical approach to determine uncertainties encountered in EM modeling that allows the determination of safe operation limits despite EM modeling errors.
Imaging Neuronal Activity at Fast Timescales in Humans using MR Elastography
Authors: Mishra Shruti , Deng Bin , Hoge W. , Tie Yanmei , Annio Giacomo , Sinkus Ralph , Patz Samuel
Published: August 2023

A stimulus-interleaved magnetic resonance elastography (MRE) sequence was utilized to demonstrate fast functionally mediated localized changes in shear wavelength during a motor task. Four healthy adult subjects underwent a visual-cue mediated right-hand finger-tapping task, switching between tapping and no-tapping blocks every 2 seconds. Areas of greatest significance between the stimulus states were localized to the left primary motor cortex. A decreased stiffness of ~30% was observed during task performance compared to rest. Compared to traditional BOLD fMRI with a 20-second block, functional MRE areas of greatest statistical difference demonstrated greater percentage change and greater spatial localization.
Ultra-high field motion-corrected MRI can visualize the mesoscale organization of the human cerebellum.
Authors: Priovoulos Nikos , Andersen Mads , Boer Vincent , van der Zwaag Wietske
Published: August 2023

The cerebellum is an important but challenging to image part of the human brain, due to its thin and highly-folded cortex. Here we demonstrate that using motion-corrected high-resolution 7T-MRI data, we can derive segmentations and surfaces of the cerebellar cortex with unprecedented accuracy in vivo. We expect this technique to greatly facilitate cognitive and clinical neuroscience research in the cerebellum.
Synthetic MRI with MR-STAT: results from a clinical trial
Authors: Kleinloog Jordi , Mandija Stefano , D'Agata Federico , van der Heide Oscar , Koktas Beyza , Jacobs Sarah , van den Berg Cornelis , Hendrikse Jeroen , van der Kolk Anja , Sbrizzi Alessandro
Published: August 2023

Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT) reconstructs multiple quantitative MR parameters from a single fast scan. This quantitative information can be leveraged for several purposes, including the synthetization of clinically desired image contrasts. Preliminary results of the first clinical trial using MR-STAT in patients with neurological diseases show that the synthetically generated contrast images (i.e., T1w, T2w, PDw and FLAIR) were acceptable for diagnostic use (5-point Likert scale
≥
3), although the score was lower compared to conventional contrasts. This highlights the potential of
MR-STAT to provide synthetic contrasts on top of quantitative maps, while reducing scan time.
Free Breathing Abdominal Tissue Quantification using 2D MR Fingerprinting with quadratic RF phase (qRF-MRF)
Authors: Huang Sherry , Chen Yong , Bolding Reid , Bittencourt Leonardo , Griswold Mark , Boyacioglu Rasim
Published: August 2023

This study presents a Pilot Tone (PT) based free-breathing technique for two-dimensional simultaneous quantification of T1, T2, T2*, fat fraction (FF), and water fraction (WF) using quadratic RF phase Magnetic Resonance Fingerprinting (qRF-MRF). We report the quantitative comparison of a cohort of 10 healthy subjects between free-breathing and breath-hold qRF-MRF as well as the comparison to standard clinical protocols. Free-breathing results are comparable to both breath-hold and standard clinical protocols (p > 0.05), indicating the stability and reproducibility of the method.
Measurement of pancreas graft temperature during cold preservation in MR scanner
Authors: Weis Jan , Korsgren Olle
Published: August 2023

Phosphorus (31P) and proton (1H) magnetic resonance spectroscopy (MRS) are the methods of choice in the assessment of the pancreas graft quality before organ or islet of Langerhans transplantation. During the transport and MR scanning hypothermic storage (4±2 oC) has to be maintained. The aim of this study was to investigate if it is possible to measure pancreas graft temperature in a MR scanner using 1H-MRS and temperature constants obtained by the calibration experiments with the water-vegetable oil phantom. The present study has shown that 1H-MRS is able to measure the graft temperature during MR scanning.
Predictive Bladder Urodynamics Using Real-Time Magnetic Resonance Imaging: A Pilot Study
Authors: Shahid Labib , Gonzalez-Pereira Juan Pablo , Johnson Cody , Li Yanheng , Rowinski David , Roldán-Alzate Alejandro
Published: August 2023

Multi-channel urodynamics is an invasive diagnostic method used to assess bladder biomechanics. MRI-based CFD has shown high potential as a clinical tool primarily focused on cardiovascular flows. In this pilot study, we demonstrate MRI-based CFD as a tool to study urodynamics. Real-time MRI on one subject provided bladder wall surfaces at multiple time points during voiding. We developed a surface mapping algorithm that processes the bladder geometries before inputting them into a CFD simulation. Coupling MRI with CFD successfully visualized and quantified urine flow dynamics. This provides a non-invasive tool to investigate urodynamics in common urological conditions such as BPH/LUTS.
Changes in Abdominal Organs from the UK Biobank Longitudinal Imaging Study
Authors: Whitcher Brandon , Thanaj Marjola , Cule Madeleine , Basty Nicolas , Sorokin Elena , Bell Jimmy , Thomas E.
Published: August 2023

We investigated changes in body composition in 3,088 free-living participants of the UK Biobank imaging study. Statistical models utilised organ and tissue segmentations from the neck-to-knee Dixon acquisitions and multiecho sequences of the liver/pancreas. A significant decrease in grip strength was observed, and small, but statistically significant, decreases in all skeletal muscle measurements. Significant increases in visceral adipose tissue and intermuscular fat in the thighs were also found in the absence of changes in BMI, waist circumference and ectopic-fat deposition. We have shown that even after a relatively short period of time significant changes in body composition are observable.
Parallel Transmit T2 Preparation for 3D T2 Mapping at Ultra-High Field
Authors: Bonanno Gabriele , Liebig Patrick , Majewsky Kurt , Kober Tobias , Hilbert Tom
Published: August 2023

T2 relaxometry at ultra-high field has the potential to become an important quantitative MRI biomarker thanks to its sensitivity to pathology. However, acquiring high-resolution isotropic T2 maps is challenging due to signal-to-noise and specific absorption rate constraints. We present a T2-mapping method for ultra-high-field MRI based on a parallel transmit T2-preparation (T2p) module integrated in a compressed sensing accelerated segmented 3D FLASH sequence. The proposed parallel transmit T2p module is investigated in phantom and in vivo experiments and compared to an adiabatic T2p module. Preliminary tests show feasibility for sub-millimeter T2 relaxometry at 7 T.
Deuterated choline tracks choline kinase α activity and enables non-invasive assessment of response to therapy in gliomas in vivo.
Authors: Taglang Celine , Batsios Georgios , Tran Meryssa , Gillespie Anne-Marie , Ronen Sabrina , Viswanath Pavithra
Published: August 2023

Elevated choline phospholipid metabolism is a hallmark of cancer. Here, we show that silencing choline kinase a (CKα), the rate-limiting enzyme in choline phospholipid biosynthesis, abrogates total choline (tCho) production from [2H9]-choline in patient-derived glioma models, indicating that tCho production from [2H9]-choline predominantly reflects CKα activity. Importantly, we show that [2H9]-choline metabolism to tCho serves to delineate tumor from normal brain in mice bearing orthotopic patient-derived low-grade gliomas. Furthermore, [2H9]-choline informs on response to therapy, at early timepoints when anatomical alterations cannot be detected, pointing to the ability of [2H9]-choline to assess pseudoprogression, which is a challenge in glioma imaging.
Comparison of clinical deuterium metabolic imaging (DMI) and hyperpolarized carbon-13 imaging at 3 T in the normal brain
Authors: Khan Alixander , Kaggie Joshua , McLean Mary , Schulte Rolf , Locke Matthew , Frary Amy , Gallagher Ferdia
Published: August 2023

Deuterium metabolic imaging (DMI) and hyperpolarized 13C-pyruvate MRI (HP-13C-MRI) are two promising approaches for non-invasive and non-ionizing imaging of tissue metabolism. Here we directly compare these two techniques at 3 T for the first time in humans. DMI using [6,6’-2H2]glucose, and 13C-MRI using hyperpolarized [1-13C]pyruvate, were undertaken in five healthy volunteers. The ratio of 13C-lactate/13C-bicarbonate (mean ±S.D. = 5.05 ±0.89) with HP-13C-MRI was higher than the equivalent 2H-lactate/2H-Glx ratio (0.43 ±0.19) with DMI, which can be explained by differences in tracer administration, subsequent timing of acquisition, and tissue physiology. The results demonstrate the two methods provide different yet complementary data.
Deuterium Metabolic Imaging of the Human Brain in vivo at 7T
Authors: Roig Eulalia Seres , De Feyter Henk M. , Nixon Terence , Ruhm Loreen , Avdievich Nikolai , Henning Anke , de Graaf Robin A.
Published: August 2023

Brain energy metabolism, for which glucose is the main fuel, is essential not only for normal brain function but also for its active role in the mechanisms that underly brain diseases. Deuterium Metabolic Imaging (DMI) is a promising MR modality for investigating whole brain energy metabolism in humans at ultra-high field. In this study, we explore the potential of DMI in the human brain in vivo at 7T. We present whole brain 3D DMI maps of well-resolved deuterated (2H) metabolite resonances of water, glucose and glutamate/glutamine (Glx) following oral administration of [6,6’-2H2]-labelled glucose.
Deep learning-based relative B1+-mapping in the human body at 7T
Authors: Krüger Felix , Aigner Christoph Stefan , Dietrich Sebastian , Hammernik Kerstin , Schmitter Sebastian
Published: August 2023

In this work, we estimate relative 2D B1+-maps from initial localizer scans using deep learning at 7T. We investigate 7 UNets and MultiResUNets architectures to estimate complex, channel-wise, relative 2D B1+-maps of 8 transmit channels from a single gradient echo localizer obtained with 32 receive channels. The networks are evaluated in 5 unseen volunteers not included in the training library by comparing the prediction with the acquired relative B1+-maps using different evaluation metrics for homogeneous B1+ phase shimming. Our approach saves additional B1+-mapping scans, and, hence, overcomes long calibration times in the human body at 7T.
MR System Stability and Quality Control using Gradient Impulse Response Functions (GIRF)
Authors: Wu Zhe , Jaffray Alexander , Vannesjo Johanna , Uludag Kamil , Kasper Lars
Published: August 2023

This study investigated the long-term stability of GIRF within an eight-month period, together with the benefits of an optimized GIRF acquisition protocol. These studies provide insight into mechanisms of image quality degrading and potentially lead to improved image quality control, generalizable to arbitrary imaging sequences.
Is diffusion tensor principal diffusivity aligned with axon fiber in the human brain white matter?
Authors: PANG YUXI
Published: August 2023

An angle offset has been identified in proton magnetic resonance transverse relaxation orientation dependencies in the human brain WM in vivo when DTI primary diffusivity direction was used as an internal reference. This angle offset has not yet been accounted for in previous studies. The present work demonstrates that the observed angle offset can be removed using an angle derived from the perpendicular and parallel diffusivities of an axially symmetric diffusion tensor regardless of axon fiber orientations. The finding from this study clearly suggests that the diffusion tensor principal diffusivity direction deviates from an axon fiber orientation in WM.
In-Vivo Probabilistic Tractography of the Extracranial Branches of the Trigeminal Nerve
Authors: Mulford Kellen , Moen Sean , Grande Andrew , Darrow David , Nixdorf Donald , Van de Moortele Pierre-Francois , Özütemiz Can
Published: August 2023

Diffusion tensor imaging-based tractography of the peripheral nerves of the face is difficult owing to the complex tissue interfaces which degrade signal and introduce artifact. In this study, we used readout segmented EPI to attempt nerve fiber tracking of the inferior-alveolar, lingual, and infra-orbital branches of the trigeminal nerve. In 6 healthy participants we were able to visualize all three nerves on both sides of the face. This technique could be applies to nerve-injury and neuropathic pain populations to assess for alterations in nerve structure.
In-vivo observations on structural aging of the inner ear – a two-center study
Authors: Thiessen Franziska , Ahmadi Seyed-Ahmad , Flanagin Virginia , Bosmans Joyce , Taskin Huseyin , Van Rompaey Vincent , Aguirre Geoffrey , Eulenburg Peter zu
Published: August 2023

We are on the road to further the role of high-resolution structural neuroimaging in the diagnostics of the most prevalent vestibular disorders. After creating an in-vivo template and atlas space for the inner ear, we have no investigated structural aging across all cochlear and vestibular anatomical regions in a representative cohort (n=87). We significant reduction along the aging process for cochlear width and length as well as some semicircular canal dimensions. Total intracranial volume was a highly relevant covariate in our analysis. Aging also seemed to affect most neuroimaging quality parameters as well and had to be controlled for.
Beyond Fractional Anisotropy: A Comparative Study of Myelin Water Fraction and Propagator Anisotropy in the Bonnet Macaque Brain
Authors: Dieckhaus Laurel , Comrie Courtney , McDermott Kelsey , Gray Daniel , Barnes Carol , Hutchinson Elizabeth
Published: August 2023

White matter (WM) is commonly studied using the Diffusion Tensor Imaging (DTI) metric Fractional Anisotropy (FA), which has limitations especially in regions where more than one fiber population exists. We compared FA to diffusion techniques (Mean Apparent Propagator (MAP-MRI)) and relaxometry techniques (Myelin Water Fraction (MWF) and Bound Pool Fraction (BPF)) mapping in the normal bonnet macaque brain. The combination of histograms and correlation analysis revealed that MAP-MRI metric, Propagator Anisotropy (PA) and MWF may offer more information about WM than FA alone, while remaining relatively correlated with FA; while BPF did not have strong association with FA or MWF.
Assessing white matter maturation and integrity in children using multi-component 3D-MR Fingerprinting and diffusion imaging
Authors: Lancione Marta , Cencini Matteo , Scaffei Elena , Cipriano Emilio , Buonincontri Guido , Ticci Chiara , Pasquariello Rosa , Battini Roberta , Canapicchi Raffaello , Biagi Laura , Tosetti Michela , (IDEA) Italian DEvelopmental Age Health Network
Published: August 2023

New biomarkers for myelination could improve the understanding of neurodevelopmental diseases and their diagnosis and treatment. We quantified Myelin Water Fraction (MWF) using MRF in a cohort of children with leukoencephalopathies and age-matched controls and we compared it to DTI-based FA. We obtained normative curves of white matter development with both techniques. MWF discriminated between controls and patients with higher sensitivity than FA, it was more myelin-specific and independent of the degree of axonal packing. Thanks to short scan time and simultaneous acquisition of other quantitative maps, MRF-based MWF may represent a valuable tool to study developmental disorders.
Functional Lung MRI at 3.0 T using Oxygen-Enhanced MRI (OE-MRI) and Independent Component Analysis (ICA)
Authors: Needleman Sarah , Kim Mina , McClelland Jamie , Tibiletti Marta , Naish Josephine , O'Connor James , Parker Geoff
Published: August 2023

Analysis of dynamic lung OE-MRI is challenging due to the presence of substantial artefacts and poor SNR, particularly at 3 T. We propose a cyclical oxygen delivery scheme and ICA to separate the oxygen-enhancement signal from these confounding factors at 3 T. The proposed method extracts a well-defined oxygen-enhancement signal that removes confounds due to proton density changes, blood flow and motion. We also demonstrate the ability to resolve the opposite enhancement effects of the parenchymal and vascular OE-MRI signals to provide information on pulmonary vasculature and gas distribution. The method is shown to be sensitive to smoking status.
Lung nodule imaging using high-performance 0.55T MRI
Authors: Wieslander Björn , Javed Ahsan , Ramasawmy Rajiv , Malayeri Ashkan , Baute Scott , O'Brien Kendall , Mancini Christine , Potersnak Amanda , Warga Cheryl , Moss Joel , Chen Marcus , Campbell-Washburn Adrienne
Published: August 2023

Lung imaging plays an important role in routine screening for lung nodules and lung cancer. Magnetic resonance imaging (MRI) has recently emerged as an alternative to computed tomography (CT) to image lung nodules. Lower field MRI offers high image quality, due to improved field homogeneity, and lower cost. We imaged 11 patients who had a total of 29 nodules visible on clinically motivated CT scans. T2-weighted images showed good agreement with CT in terms of nodule size and diameters and malignant nodules were more often visible on diffusion weighted images (b = 800).
Longitudinal comparison of quantitative UTE lung MRI and CT biomarkers in interstitial lung disease
Authors: Chan Ho-Fung , Baldwin Timothy , Barker Harry , Stewart Neil , Eaden James , Hughes Paul , Weatherley Nicholas , Astley Joshua , Tahir Bilal , Johnson Kevin , Karwoski Ronald , Bartholmai Brian , Tibiletti Marta , Leonard Colm , Skeoch Sarah , Chaudhuri Nazia , Bruce Ian , Parker Geoff , Bianchi Stephen , Wild Jim
Published: August 2023

UTE lung MRI approaches the diagnostic quality of CT, opening up the possibility for longitudinal follow-up of interstitial lung disease (ILD) progression. Two quantitative biomarkers of UTE lung signal were developed for monitoring longitudinal change in ILD and benchmarked against quantitative CT CALIPER measurements. Normalized UTE lung signal and UTE high percentage (based on 95% cutoff of healthy UTE lung values) was significantly different between nine healthy volunteers and sixteen ILD patients. Longitudinal change in UTE biomarkers correlated with change in CT CALIPER ILD% in the ILD patients, and most-strongly correlated to CT ground-glass changes in the lung parenchyma.
Improving Efficiency of Ultra-short Echo Time MRI in Neonatal Lungs with a FLORET Spiral Trajectory
Authors: Hahn Andrew , Higano Nara , Willmering Matthew , Stewart Neil , Woods Jason , Fain Sean
Published: August 2023

State-of-the-art structural pulmonary MRI of neonatal intensive care unit patients has previously been performed using 3D radial UTE. Performance is high yet scan times can be 15 minutes or more due to the low sampling efficiency of radial trajectories. Here we explore FLORET UTE in this application and demonstrate comparable image quality to the state-of-the-art in approximately 25% of the scan time. Lung parenchymal SNR is maintained, and the spiral trajectory provides a higher parenchymal signal relative to muscle. Shorter scan times reduce the opportunity for bulk motion and risk to this sensitive population.
Imaging lung water redistribution using 0.55T ultrashort echo time MRI
Authors: Seemann Felicia , Javed Ahsan , Chae Rachel , Potersnak Amanda , Baute Scott , O’Brien Kendall , Ramasawmy Rajiv , Lederman Robert , Campbell-Washburn Adrienne
Published: August 2023

Quantification of changes in lung water using MRI may provide clinical value in early diagnosis of heart failure. In this study, we demonstrate the ability of our 3D free-breathing spiral ultrashort-TE sequence to quantify and capture changes in lung water using a high-performance 0.55T MRI system. A phantom containing mixtures of water and deuterium oxide at varying concentrations was used to validate water density quantification. Our proposed approach captured the gravity-induced redistribution of lung water, achieved by imaging subjects in the supine and prone positions.
Extra-ocular muscle volume, T2water and fat fraction are slightly increased in patients with myasthenia gravis
Authors: Keene Kevin , Verschuuren Jan , Notting Irene , Tannemaat Martijn , Beenakker Jan-Willem , Kan Hermien
Published: August 2023

Quantitative MRI of the extra-ocular muscles might have diagnostic value and play a role in therapeutic monitoring in myasthenia gravis (MG). Our data show a slight increase in volume, fat fraction and T2water in extra-ocular muscles of MG patients compared to controls. Volume and fat fraction changes were most pronounced in chronic MG patients, T2water changes were most pronounced in recently diagnosed and untreated MG patients. The absence of gross structural changes implies that eye muscle weakness might be reversible, even in chronic patients with residual ophthalmoplegia.
Cell proliferation correlates with glucose metabolic fluxes in mouse glioblastoma subtypes as assessed via deuterium MRS
Authors: Simoes Rui , Henriques Rafael , Cardoso Beatriz , Fernandes Francisca , Carvalho Tania , Shemesh Noam
Published: August 2023

Dynamic glucose-enhanced deuterium MRS (DGE 2H-MRS) coupled with Marchenko-Pastur PCA denoising has shown potential for in vivo quantification of glucose metabolism through glycolysis and mitochondrial oxidation in a mouse model of glioblastoma, and for assessment of pathway flux modulations according to tumor heterogeneity. Here, we extend this approach to immunocompetent mouse glioblastoma subtypes with marked differences in tumor cell metabolism and histopathologic features, to utterly demonstrate the potential of DGE 2H-MRS for non-invasive metabolic phenotyping of glioma, or other cancers with mitochondrial oxidation dependencies, according to key features of the tumor microenvironment such as cell proliferation.
BladeNet: Rapid PROPELLER Acquisition and Reconstruction for High spatio-temporal Resolution Abdominal MRI
Authors: Shimron Efrat , De Goyeneche Alfredo , Wang Ke , Halgren Alma , Syed Ali , Vasanawala Shreyas , Lustig Michael
Published: August 2023

To improve bowel wall imaging in abdominal pediatric MRI scans, we propose a multi-phase single-shot fast spin echo (SSFSE) PROPELLER acquisition with novel deep learning reconstruction. This acquisition offers shorter scan time and thus higher temporal resolution, PROPELLER built-in motion correction, and alias-free images; these however exhibit spatial blurring. Our approach leverages the blurring-axis temporal rotation and data redundancy; we train a network to recover high-frequency spatial details from consecutive frames. Retrospective simulations with data from balanced SSFP scans show that this approach yields reconstructions with high spatio-temporal resolution and motion-correction, which are essential for pediatric abdominal imaging.
Designing a Clinical Decision Support System for MRI Radiology Titles Using Machine Learning Techniques and Electronic Medical Records
Authors: Shokrollahi Peyman , Chaves Juan Zambrano , Lam Jonathan , Sharma Avishkar , Pal Debashish , Bahrami Naeim , Chaudhari Akshay , Loening Andreas
Published: August 2023

The use of inappropriate radiology protocols introduces risk of missed and incomplete diagnoses, thus endangering patient health, potentially prolonging treatment, and increasing healthcare costs. A clinical decision support system based on machine learning and electronic medical records of patients undergoing MRI was developed to predict radiology titles and their probabilities for radiologist review. A cumulative F1-score of ~85% was obtained for the top three predicted titles. The proposed system can guide physicians toward selecting appropriate titles and alert radiologists of potentially inappropriate selections, thereby improving imaging utility and increasing diagnostic accuracy, which favors better patient outcomes.
On the Reliability of Connectome Harmonic Decompositions of Human Brain Structure and Function
Authors: Winston Brian , Taylor Hoyt , Yap Pew-Thian , Barrett Frederick , Pekar James
Published: August 2023

The connectome harmonic decomposition provides a principled approach to dimensionality reduction of human brain functional data using the eigenmodes of the graph Laplacian derived from the anatomical connectome. In the present report, test-retest data from the Human Connectome Project are used to assess the reliability of the structural harmonics, and of decompositions of resting-state functional MRI data using these harmonics. For both structure and function, reliability was higher within than between subjects, and decreased with harmonic rank.
Functional MRI of mice olfactory bulbs at 15.2T reveals characteristic activation patterns when stimulated by different odors
Authors: Chitrit Odélia , Bao Qingjia , Chuartzman Silvia , Silkha Noga , Kimchi Tali , Frydman Lucio
Published: August 2023

Single-shot fMRI executed at ultrahigh fields can reveal valuable insight about brain function, if it successfully overcomes field inhomogeneity problems. Spatiotemporal Encoding provides a route for achieving this, enabling studies on the olfactory bulbs of mice at 15.2T. Images collected with a 125 µm in-plane resolution yielded remarkably large and well-defined responses to olfactory cues, particularly in males. These were unambiguously linked to olfaction via single-nostril experiments. The experiments highlighted specific activation regions in the external plexiform region and in glomeruli in the lateral part of the bulb, when stimulated by aversive or appetitive odors, respectively.
Sensitivity of dMRI with TBSS analysis to WM pathology in SLE: influence of field strength, acquisition approach and post-processing strategy
Authors: Kornaropoulos Evgenios , Winzeck Stefan , Knutsson Linda , Correia Marta , Sundgren Pia , Nilsson Markus
Published: August 2023

We examined whether more advanced dMRI increase the sensitivity to white matter pathology in systemic lupus erythematosus. Specifically, we examined whether more advanced acquisitions (DKI versus DTI, 7T versus 3T) and more complex processing (e.g. denoising, Gibbs-ringing removal) provide increased sensitivity. Tract-based spatial statistical analysis was applied, and the fraction of significant voxels in the white matter skeleton was used as the sensitivity metric. Results showed that the choice of the acquisition protocol had a greater impact on sensitivity than the choice of the post-processing strategy. 3T-DTI was more sensitive than 3T-DKI and 7T-DTI, regardless of the applied post-processing pipeline.
Feasibility study for conductivity reconstructions from spin-echo images using artificial neural network with simulation data in 3T MR system
Authors: Jung Kyu-Jin , Mandija Stefano , Kim Jun-Hyung , Cui Chuanjiang , Choi Sanghyeok , Yi Jaeuk , Park Mina , van den Berg Cornelis A.T. , Kim Dong-Hyun
Published: August 2023

Phase-based Electrical properties tomography is a non-invasive imaging technique that uses MRI systems to measure the tissue conductivity. However, the conductivity reconstruction process causes problems such as noise amplification and boundary artifact. To address such limitations, several DL-based reconstruction methods were proposed. Building upon these works, we propose an ANN-based conductivity reconstruction method trained only on simulation dataset. The proposed method was studied with the aim of: (a) approaching ground-truth conductivity values, (b) noise-robustness, (c) higher image resolution, (d) generalization to clinical data. The feasibility was investigated on simulations and TSE in-vivo data (one healthy volunteer, two meningioma cases).
­The Double Bent Dipole (DBD): A hybrid element designed for combined RF/B0 shimming for imaging at 10.5T
Authors: Bratch Alexander , Radder Jerahmie , Sadeghi-Tarakameh Alireza , Adriany Gregor , Ugurbil Kamil , Rutt Brian
Published: August 2023

In this work, we demonstrate a new double bent dipole geometry for use as a hybrid RF/B0 shimming element for 10.5T imaging, featuring two B0 shimming channels per RF channel. Initial simulations compare this element to standard dipoles and loops. Bench assessments and simulations further demonstrate excellent inter-element decoupling, and initial steps toward a 32-channel Tx/64-channel B0 array show promising results.
Tracking developmental connectopathy in 22q11.2 deletion syndrome with cross-species fMRI
Authors: Alvino Filomena Grazia , Gini Silvia , Galbusera Alberto , Sastre David , Rocchi Federico , Pagani Marco , Montani Caterina , Papaleo Francesco , Pasqualetti Massimo , Bearden Carrie , Gozzi Alessandro
Published: August 2023

22q11.2 Deletion Syndrome (22q11DS), a major risk factor schizophrenia and autism, is often associated with disrupted brain connectivity. However, the developmental and neural underpinnings of brain connectopathy in 22q11DS remain unclear. Using mouse fMRI, we found that 22q11DS-related dysconnectivity exhibits a stereotypical developmental trajectory, with widespread functional hyperconnectivity in pre-pubertal mice reverting to focal fronto-hippocampal hypoconnectivity in adulthood. Notably, juvenile hyperconnectivity, but not adult hypoconnectivity, was completely rescued by a GSK3β antagonist. Finally, guided by our mouse model data, we identified a similar developmental trajectory in 22q11DS patients, hence corroborating the translational validity of these findings.
Blood-brain barrier water exchange rate is associated with cognitive performance in mild cognitive impairment and early Alzheimer’s disease
Authors: Morgan Catherine , Shao Xingfeng , Govender Jane , Manson Tabitha , Suresh Vinod , Jansson Deidre , Wang Danny , Thomas David , Tippett Lynette , Dragunow Michael
Published: August 2023

Blood-brain barrier (BBB) dysfunction has been observed in multiple neurodegenerative conditions, including mild cognitive impairment (MCI) and Alzheimer’s disease (AD). However recent concerns on the repeated use of Gadolinium based contrast agents (GBCAs), prompted us to investigate alternative, non-invasive methods for measuring BBB health. Diffusion-prepared arterial spin labelling (DP-ASL) imaging was implemented at 3T to determine water exchange rates (Kw) in 55 participants, comprising MCI, early AD and control participants. We found Kw to be associated with cognitive performance, suggesting it may be a useful imaging biomarker of early AD pathology.
Multimodal MRI-derived phenotypes in preclinical Alzheimer’s Disease: results from the EPAD cohort
Authors: Lorenzini Luigi , Ingala Silvia , Wink Alle Meije , Kuijer Joost , Wottschel Viktor , Sudre Carole , Haller Sven , Molinuevo José Luis , Gispert Juan Domingo , Cash David , Thomas David , Vos Sjoerd , Ferran Prados , Petr Jan , Wolz Robin , Palombit Alessandro , Schwarz Adam , Chételat Gael , Payoux Pierre , Di Perri Carol , Pernet Cyril , Frisoni Giovanni , Fox Nick , Ritchie Craig , Wardlaw Joanna , Waldman Adam , Barkhof Frederik , Mutsaerts Henk
Published: August 2023

Image-derived phenotypes (IDPs) from multimodal MRI sequences constitute an important resource that allows the characterization of brain alterations in the early stages of Alzheimer diseases and other neurodegenerative conditions. Here, we showed the computation of multimodal IDPs from the European Prevention of Alzheimer Dementia (EPAD) cohort and assessed their relationship with non-imaging markers of neurodegeneration. We demonstrated the clinical relevance of IDPs to uncover early brain alteration in AD by showing expected association with non-imaging data.
Maternal Blood Volume Measurements of Human Placenta with Fetal Growth Restriction using Ferumoxytol-Enhanced MRI
Authors: Chen Ruiming , Fain Sean , Magness Ronald , Antony Kathleen , Iruretagoyena J. Igor , Bird Ian , Shah Dinesh , Wieben Oliver , Johnson Kevin
Published: August 2023

Fetal growth restriction (FGR) has been associated with insufficient development of utero-placental vasculature, which could be identified using maternal placental blood volume measurements. This preliminary study uses ferumoxytol-enhanced MRI to measure placental blood volume of three FGR subjects using variable flip angle T1-mapping. Mean values of maternal fractional, placental, and total blood volumes are reported, as well as changes in placental R1 values between two time points after contrast injection. We observe local placental heterogeneities, including regions with low factional blood volume in the subjects.
Quantifying Placental Structure and Function over Gestation with Combined T2*-diffusion MRI
Authors: Slator Paddy , Hutter Jana , Jackson Laurence , Ho Alison , Story Lisa , Chappell Lucy , Rutherford Mary , Hajnal Joseph , Alexander Daniel
Published: August 2023

We quantify placental structure and function over gestation with combined diffusion-relaxometry MRI. We apply a simultaneous T2*-diffusion acquisition protocol to a cohort of 65 pregnant participants, and hence estimate T2* and ADC maps, T2*-ADC spectra, and map T2*-ADC spectrum components with a data-driven technique, InSpect. We show InSpect is more sensitive to placental maturation than separate T2* and ADC mapping alone.
Myocardial Metabolic Changes Detected Post-COVID-19 with Hyperpolarized Pyruvate
Authors: Zaha Vlad , Ma Junjie , Park Jae Mo , Fares Munes , Hendren Nicholas , Carter Spencer , Rao Anjali , Vamsee Ravi , Ganigara Madhusudan , Nagiub Mohamed , Hussain Mohammad , La Hoz Ricardo , Cutrell James , Mammen Pradeep , Drazner Mark , de Lemos James , Malloy Craig , Grodin Justin
Published: August 2023

Noninvasive detection of myocardial inflammation can be challenging. Up to 73% of patients recovered from COVID-19 had increased native T1 on cardiac MRI1 representing inflammation or edema. Therefore, we tested whether hyperpolarized (HP) [1-13C]pyruvate detectis post-COVID-19 inflammation in the myocardium. HP [1-13C]lactate has been suggested as a surrogate imaging marker of inflammation in the heart2,3, attributed to increased glycolytic activity in infiltrating white cells plus a possible increase in activity of lactate dehydrogenase. We demonstrate the feasibility of imaging with HP [1-13C]pyruvate as noninvasive method to detect metabolic changes that may identify cardiac inflammation in the convalescent stage after COVID-19.
Automatic Assessment of Fetal Gestational Age using Bayesian Deep learning Method
Authors: Largent Axel , Murnick Jonathan , Lu Yuan-Chiao , Kapse Kushal , Andersen Nicole , Richmann Todd , De Asis-Cruz Josepheen , Quistorff Jessica , Lopez Catherine , Andescavage Nickie , Limperopoulos Catherine
Published: August 2023

Monitoring fetal brain development is crucial for early diagnosis of brain malformations and other congenital disorders. Standard methods to monitor brain maturation are mainly based on subjective and time-consuming visual analysis of the progression of sulcation. Our study proposed a Bayesian deep-learning method (DLM) for automatic assessment of fetal-gestational age (GA), and accurate and efficient identification of fetuses with abnormal brain development. Our Bayesian DLM showed excellent performance in predicted GA (mean-absolute-error = 0.928 weeks) and compared favorably with other state-of-the-art methods. This method may be used in clinical practice for monitoring fetal-brain development and early diagnosis of fetal brain malformations.
Improved acquisition efficiency in T2-weighted fetal MRI with optimized variable flip angles and prospective wave-encoding
Authors: Arefeen Yamin , Gagoski Borjan , Bilgic Berkin , Grant Ellen , Adalsteinsson Elfar
Published: August 2023

Fetal MRI utilizes Half-Fourier-acquisition-single-shot-turbo-spin-echo (HASTE) for motion robust imaging. However, specific-absorption-rate (SAR) constraints from the refocusing pulse train lengthens scan time and increases vulnerability to motion-induced artifacts. Variable refocusing flip angle (VFA) acquisitions improve efficiency, but may suffer from poor contrast-to-noise-ratios (CNR). We propose an optimization technique for VFA that retains ~90% CNR with 2.5x SAR reduction. Furthermore, we demonstrate the first application of wave-encoding in fetal MRI at Rin-plane = 3-fold prospectively under-sampled acquisitions. Combining HASTE, VFA, and wave-encoding improves acquisition time with reduced repetition times and shorter echo-trains and could enable simultaneous-multislice acquisitions for further acceleration.
Prediction of survival in paediatric brain tumour patients using multicentre leakage-corrected perfusion MRI
Authors: Withey Stephanie , MacPherson Lesley , Oates Adam , Powell Stephen , Novak Jan , Abernethy Laurence , Pizer Barry , Grundy Richard , Morgan Paul , Bailey Simon , Mitra Dipayan , Arvanitis Theodoros , Auer Dorothee , Avula Shivaram , Peet Andrew
Published: August 2023

Dynamic susceptibility (DSC-) MRI provides measures of relative cerebral blood volume (rCBV) in paediatric brain tumours. Correction of rCBV for the effects of contrast agent leakage can be done using post-processing techniques. Eighty-five patients with a range of paediatric brain tumours underwent DSC-MRI scans at 4 centres using variable protocols. Leakage-corrected and uncorrected DSC-MRI parameters were calculated and patients were followed up. Median DSC-MRI parameters significantly predicted overall survival.
Phase distribution graphs for differentiable and efficient simulations of arbitrary MRI sequences
Authors: Endres Jonathan , Dang Hoai , Glang Felix , Loktyushin Alexander , Weinmüller Simon , Zaiss Moritz
Published: August 2023

We propose an alternate method for simulating arbitrary MRI sequences, forming complete Bloch simulations. It is closely related to Extended Phase Graphs but imposes no restrictions on the alignment of timing or gradients, extends it to support T2' relaxation and 3D gradient encoding, is fully differentiable, provides additional insight into the composition of the measured signal while outperforming isochromat-based Bloch simulations in execution speed by using an analytical description of the signal instead of relying on a Monte-Carlo simulation.
Rotational invariants of the cumulant expansion (RICE)
Authors: Coelho Santiago , Fieremans Els , Novikov Dmitry
Published: August 2023

We studied the symmetries of the diffusion and covariance tensors, both accessible through a general b-tensor acquisition. We showed that there is an unexplored contrast in the non-symmetric part of the covariance tensor and use it to compute the size-shape covariance of compartmental diffusion tensors. We measure all rotational invariants of the cumulant tensors in a normal volunteer, explore the novel size-shape contrast, and provide the relations between these invariants and typical diffusion contrasts.
Voxel-wise compartmental modelling of blood-brain barrier water exchange measurements using FEXI
Authors: Powell Elizabeth , Ohene Yolanda , Battiston Marco , Parkes Laura , Parker Geoff
Published: August 2023

We propose compartmental modelling of blood-brain barrier (BBB) water exchange measurements using diffusion-filtered exchange imaging (FEXI), with the aim of providing greater biophysical insight into BBB function than is possible using the apparent exchange rate (AXR) approach. As relaxation time differences between blood and extravascular tissue have not yet been accounted for in FEXI-based BBB permeability measurements, we use simulations to quantify potential biases in exchange rates from both the AXR and compartmental approaches. Finally, we evaluate the repeatability of the AXR and compartmental models in a cohort of healthy subjects.
Respiration artifact-free 3D DESS T2 mapping of the human brain
Authors: Kadalie Emile , Trotier Aurélien , Corbin Nadège , Miraux Sylvain , Ribot Emeline
Published: August 2023

The Dual Echo Steady State (DESS) sequence has the potential to be used for 3D human brain imaging and 3D T2 mapping. It is however known to be sensitive to respiration. The DESS sequence was therefore modified to include a self-gating approach in order to investigate the influence of breathing on brain images and then extract artifact-free images. To apply this method for high resolution T2 mapping at 3T, an acceleration method compatible with Compressed Sensing was implemented to maintain a clinically acceptable acquisition time.
Microstructure-Informed Synthetic Axons (MISA): generating synthetic axons from 3D histology
Authors: Andersson Mariam , Rafael-Patino Jonathan , Kjer Hans Martin , Pizzolato Marco , Girard Gabriel , Thiran Jean-Philippe , Dyrby Tim
Published: August 2023

Changes in diffusion properties of the intra-axonal space can be linked to brain health and function. Monte Carlo simulations of diffusion using realistic substrates are important for sequence design and for understanding diffusion MRI signals observed ex vivo and in vivo. However, it is difficult to construct tissue phantoms that accurately reflect compartment morphology. Here, we present the framework MISA for the generation of Microstructure-Informed Synthetic Axons. MISA uses statistical descriptions of axonal morphology from 3D histology to mimic real axons. We show here that MISA axons match axons from 3D histology in terms of their diffusion properties.
Intravoxel incoherent motion (IVIM) MRI for juvenile idiopathic arthritis in the knee: a prospective pilot study
Authors: Stumpf Kilian , Huch Britta , Bracher Anna-Katinka , Hüfken Thomas , Beer Meinrad , Neubauer Henning , Rasche Volker
Published: August 2023

Intravoxel incoherent motion (IVIM) imaging allows the quantification of diffusion and pseudo-perfusion in tissues and has been proposed as an alternative to conventional contrast agent enhanced (CE) T1-weighted scans. Its qualitative benefits for diagnosing juvenile idiopathic arthritis in the knee has previously been demonstrated. In this work, quantitative data of diffusion and perfusion fraction values between synovitis patients and healthy volunteers were compared in a prospective setting.
Longitudinal evaluation of bundle-wise diffusion metrics in a region of fiber crossing for axonal degeneration and inflammation
Authors: Coronado-Leija Ricardo , Narvaez Omar , Rios Ricardo , Scherrer Benoit , Ramirez-Manzanares Alonso , Concha Luis
Published: August 2023

Single fiber methods, such as the diffusion tensor, cannot accurately determine per-bundle characteristics in voxels occupied by multiple axonal populations specially in the case of pathology when they have different diffusion properties. In this work, we used animal models of axonal degeneration and inflammation to evaluate longitudinally the sensitivity of bundle specific metrics provided by three multi-fiber methods in a region of crossing fiber in which only one fiber population is injured.
Comparison of diffusion MRI models for white matter in simulations and in early human brain development
Authors: Liao Ying , Coelho Santiago , Chen Jenny , Ades-Aron Benjamin , Novikov Dmitry , Fieremans Els
Published: August 2023

Biophysical modeling of diffusion MRI is instrumental in achieving specificity to tissue microstructure in human white matter. The “Standard Model” (SM) framework encompasses many approaches assuming multiple Gaussian compartments. To robustly estimate SM parameters, different constraints and techniques have been applied, resulting in different outcomes. Here we evaluate the precision and accuracy of commonly used implementations and constraints for SM parameter estimation, and compare their results both in simulations and in early human brain development.