bluuebunny/crossref_metadata_2025 huggingface dataset:
High spatial and temporal resolution absolute temperature imaging of Ethylene Glycol
Authors: Odéen Henrik , Hofstetter Lorne , Kim Seong-Eun , Parker Dennis
Published: August 2023

Multi-echo MRI was used to image and detect peak spacing between OH groups in ethylene glycol. The OH peak spacing was shown to change linearly with temperature, and the fit from one experiment could be used to accurately reconstruct absolute temperatures from another experiment. This approach can provide high spatial and temporal resolution absolute temperature measurements for ex vivo applications.
Smart MetaBox: Metamaterial arrangement for volume-homogeneous SNR enhancement
Authors: Philipp Dennis , Stoja Endri , Konstandin Simon , Wilke Robin , Betancourt Diego , Bertuch Thomas , Jenne Juergen , Umathum Reiner , Guenther Matthias
Published: August 2023

A metamaterial arrangement that encloses a volume "metaBox" is shown to yield a significant and volume-homogeneous SNR enhancement in 3T MRI. Due to the integration of non-linear components, the structure self-detunes in Tx whilst being resonant in Rx. Fine-tuning capabilities are included in two different prototypes via (i) a manually trimmable capacitor and (ii) a Bluetooth-controlled digital capacitor that allows for a wireless interface. On-bench characterization as well as MRI experiments verify the functionality of the device. Thus, the metaBox is ideally suited for, e.g., imaging of extremities.
Combining Arterial Blood Contrast with BOLD improves fMRI laminar specificity.
Authors: Priovoulos Nikos , Oliveira Icaro , Poser Benedikt , Norris David , van der Zwaag Wietske
Published: August 2023

BOLD fMRI is widely applied in human neuroscience, but is limited in its spatial specificity compared to cerebral blood volume approaches due to its venous bias. Here we added cerebral blood-volume weighting based on magnetization transfer (Arterial Blood Contrast) to a BOLD submillimeter acquisition at 7T. Adding Arterial Blood Contrast helped differentiate the deep and superficial cortical responses in the human primary motor cortex. The results suggest that combining Arterial Blood Contrast with BOLD can improve the fMRI spatial specificity while retaining high sensitivity.
Cortical-depth dependent functional connectivity at the human auditory cortex during the resting state and under complex naturalistic stimuli
Authors: Lee Hsin-Ju , Lee Hankyeol , Uludag Kamil , Ahveninen Jyrki , Lin Fa-Hsuan
Published: August 2023

We explored the functional connectivity of the human auditory cortex with cortical depth analysis and compared music listening and the resting state using 7T fMRI with 0.8 mm isotropic resolution. Tonotopic maps, principal component analysis, and seed-based correlation revealed network topologies and suggested functions supporting feed-forward and feed-back processing. The feed-forward process is manifested by the reduced correlation to the contralateral auditory cortex during music-listening at the intermediate cortical depths. The feed-back processing is associated with a network like the tonotopic organization, which was stable between the resting and music listening but more correlated with the contralateral auditory cortex.
BraCoil – preliminary performance evaluation of a wearable breast coil array for 3 T MR mammography
Authors: Nohava Lena , Obermann Michael , Frass-Kriegl Roberta , Isaieva Karyna , Dessale Claire , Felblinger Jacques , Laistler Elmar
Published: August 2023

A dedicated radio frequency coil design for MR mammography needs to optimize sensitivity, reduce scan time, and improve patient comfort to ultimately facilitate diagnosis. We investigate signal-to-noise ratio and parallel imaging performance differences between widely used commercial 16-/18-channel receive coils for breast MRI at 3 T in prone and supine position and an in-house developed 28-channel wearable coil array (“BraCoil”). An SNR gain of up to a factor of 6 with BraCoil was found in this phantom study.
A 4-channel flexible array with integrated B0 shimming for 3 T
Authors: Gruber Bernhard , Obermann Michael , Nohava Lena , Zaitsev Maxim , Wald Lawrence , Stockmann Jason , Laistler Elmar
Published: August 2023

Integrated B0 shimming capability with RF coil arrays has already shown advantages in dense configurations. For highly flexible arrays this approach is a challenge due to the bulky RF chokes required to bypass the segmenting capacitors of classical loop coils. In this work we present a flexible 4-channel coaxial coil array module with integrated B0 shimming requiring only two RF chokes per shim channel and thereby demonstrate the feasibility of integrating B0 shim capability into flexible arrays.
RF Coils for Evaluation of Duchenne Muscular Dystrophy Biomarkers at 4.7 T
Authors: Valle Edith , Carrell Travis , Nghiem Peter , Wright Steven , McDougall Mary
Published: August 2023

Duchenne muscular dystrophy (DMD) is a debilitating genetic muscle disorder. To study and characterize this disease efficiently, our group has developed a set of custom single-tuned and multi-tuned coils. We have acquired 1H, 23Na and 31P data from 20 healthy and diseased samples. Some of the studied biomarkers have shown clear distinctions between healthy and diseased samples.
Automated 3D MRI Decision Tree to guide referral and diagnosis of parkinsonian disorders
Authors: Kim Jisoo , Willett Andrew , Crotty Grace , Mesidor Merlyne , Bay Camden , Xu Xiaoyin , Qin Lei , Khurana Vikram , Young Geoffrey
Published: August 2023

For screening and diagnosis of Parkinson disease (PD), progressive supranuclear palsy (PSP), and multiple system atrophy-parkinsonian/cerebellar subtypes (MSA-P/MSA-C), we propose a two-step decision tree using a novel MRI biomarker and volumetric measures. MRIs from 50 MSA-C, 22 MSA-P, 50 PSP, 50 PD, and 172 age/legal-sex-matched control were used for fully automated volumetric analysis of the brain and brainstem. Sensitivity/specificity for diseased vs control was 90.1/90.7%. Then, a comprehensive tree with the diseased group yielded sensitivity/specificity of 81.9/93.0% (MSA), 94.0/88.5% (MSA-C), 54.5/96.0% (MSA-P), 74.0/86.0% (PD), 76.0/98.4% (PSP). We provide a reproducible and specific diagnostic tool for screening and initial differential diagnosis.
Automatic DTI measures in the superficial white matter associated with cognitive decline and CSF amyloid-β42 in neurodegenerative dementia
Authors: Contarino Valeria , Siggillino Silvia , Arighi Andrea , Scola Elisa , Fumagalli Giorgio , Conte Giorgio , Rotondo Emanuela , Galimberti Daniela , Pietroboni Anna , Carandini Tiziana , Leemans Alexander , Bianchi Anna Maria , Triulzi Fabio
Published: August 2023

Diffusion tensor imaging (DTI) studies showed superficial white matter (SWM) alterations in Alzheimer’s disease (AD). The study aims to investigate the relationship between DTI in the SWM and CSF biomarkers in neurodegenerative dementia (ND). 93 ND patients were retrospectively recruited and images were processed for automatic segmentation of lobar white matter and Diffusion tensor imaging (DTI). Spearman’s correlation tests were performed between lobar DTI measures in the SWM, CSF biomarkers and clinical data. DTI measures in the SWM strongly correlated with Mini-Mental State Examination (MMSE) and amyloid-β42 suggesting SWM DTI as a candidate in-vivo non-invasive clinical and preclinical biomarker.
Unloaded-to-loaded changes in regional tibial cartilage T1ρ and T2: Utilization of an MRI compatible loading device
Authors: Argentieri Erin , Zhu Andrew , Bansal Sonia , Wach Amanda , Pekmezian Ashley , Breighner Ryan , Potter Hollis , Maher Suzanne , Koff Matthew
Published: August 2023

Unloaded and loaded tibial cartilage T1ρ and T2 values were evaluated regionally. Only T1ρ, significantly changed from the unloaded-to-loaded condition. Shortening of loaded T1ρ values may be attributed to matrix water loss due to PG damage and attendant loss of the cartilage FCD. Though not all regions exhibited significant changes in unloaded-to-loaded T1ρ values, previous work demonstrated that tibial cartilage tissue and fibril strains follow the pattern of changes in FCD distribution. Inter-regional T2 variation increased from unloaded-to-loaded conditions, suggesting that T2 values were affected by a decreased FCD of cartilage that allowed water to move more freely between regions.
Improved accuracy and precision in 3D T2 mapping of knee cartilage with dictionary fitting and patch-based denoising
Authors: Kuhn Simon , Bustin Aurélien , Lamri-Senouci Aicha , Rumac Simone , Ledoux Jean-Baptiste , Colotti Roberto , Bastiaansen Jessica , Yerly Jérôme , Favre Julien , Omoumi Patrick , van Heeswijk Ruud
Published: August 2023

We implemented and compared three different reconstructions for 3D T2 mapping of the knee: I) a standard image reconstruction followed by an analytical fit, II) a standard image reconstruction followed by a dictionary fit, and III) a denoised image reconstruction followed by a dictionary fit. We optimized and compared these techniques in phantoms, five healthy volunteers, and five patients with mild osteoarthritis. The third reconstruction resulted in the highest accuracy and precision while retaining the spatial resolution, and allowed the load-bearing cartilage in the mild-OA patients to be differentiated from that in the healthy volunteers.
Feasibility of Simultaneous Bilateral Hip Quantitative MRI
Authors: Roach Koren , Han Misung , Link Thomas , Souza Richard , Majumdar Sharmila , Pedoia Valentina
Published: August 2023

Our group recently developed simultaneous bilateral hip MR acquisition methods to reduce total imaging time and employ during longitudinal evaluations of hip OA. This study evaluated the ability of simultaneous bilateral 3D FSE Cube and MAPSS acquisitions to maintain relevant morphological information compared to unilateral acquisitions. The mean T1ρ and T2 values of the simultaneous bilateral MAPSS acquisitions were not significantly different from unilateral acquisitions and relaxometry map patterns were preserved. Additionally, our simultaneous bilateral hip protocol promoted high resolution 3D Cube images for morphological abnormality detection and reduced scan time by 40%, to under 30 minutes.
High resolution Multi-voxel spectroscopy using CSI-semi-LASER for mouse brain preclinical studies
Authors: Javed Zoona , Martinez Gary , Candiota AnaPaula , Cabanas Miquel , Lope Silvia
Published: August 2023

This work describes an improved multi-voxel Chemical shift imaging (CSI) pulse sequence that uses the semi-LASER localization approach. Bruker CSI sequence containing PRESS localization block (CSI-PRESS) was modified by replacing the aforementioned PRESS block with a semi-LASER one resulting in a CSI-semi-LASER sequence. This work was developed on a 7T Bruker BioSpec 70/30 USR spectrometer running ParaVision 5.1 which does not contain neither built-in blocks for semi-LASER sequence nor adiabatic pulses. The sequence was tested in wt C57/BL6 mouse brain and compared with the stock CSI-PRESS sequence. The results show improved homogeneity and reduction in chemical shift displacement error (CSDE).
Choroid plexus tissue perfusion and blood to CSF barrier function (BCSFB) in rats measured with continuous arterial spin labeling
Authors: Lee Hedok , Ozturk Burhan , Stringer Michael , MacIntosh Bradley , Rothman Douglas , Benveniste Helene
Published: August 2023

In this study choroid plexus tissue perfusion and blood to CSF barrier function in rats were studied using long and short TE continuous arterial spin labeling technique. Non-mono exponential perfusion weighted signal decay in the CP was modelled by a two-compartment perfusion model and we report that partial volume effect is significant and must be considered to derive accurate choroid plexus tissue perfusion measurements.
DTI and fMRI Biomarkers in a Pig Model of Pediatric Traumatic Brain Injury
Authors: Netzley Alesa , Badachhape Andrew , Wade-Kleyn Lauren , Huang Jie , Munoz Kirk , Colbath Aimee , Meoded Avner , Pelled Galit
Published: August 2023

The goal of this work is to identify MRI biomarkers of mild traumatic brain injury (mTBI) using a pig model of pediatric concussion. We have found changes in the brain using DTI and fMRI in the days and weeks immediately following injury. We also collected data from a battery of cognitive, emotional, and motor assessments. Together, we anticipate these data will help us to identify biomarkers of injury that will improve diagnostics of children to decrease the risk of post-injury complications.
Nigral Neuromelanin MRI Changes in Isolated Rapid Eye Movement Sleep Behavior Disorder Using Deep Learning
Authors: Gaurav Rahul , Valabrègue Romain , Pyatigorskaya Nadya , Mangone Graziella , Leu-Semenescu Smaranda , Corvol Jean-Christophe , Vidailhet Marie , Arnulf Isabelle , Lehericy Stephane
Published: August 2023

Isolated REM sleep behavior disorder (iRBD) is considered a prodromal stage of parkinsonism. Neurodegenerative changes in the substantia nigra pars compacta (SNc) in parkinsonism can be detected using neuromelanin-sensitive MRI. In this cross-sectional, observational, case-control study, we investigated changes in neuromelanin in participants with iRBD compared to Parkinson’s disease and healthy volunteers in the SNc segmented automatically using convolutional neural network-based U-net architecture. The iRBD participants had reduced neuromelanin content at an intermediate level between the values in HV and PD patients.
Assessment of resting-state networks in Alzheimer’s disease using combined spin- and gradient-echo fMRI
Authors: Keeling Elizabeth , Bergamino Maurizio , Sisco Nicholas , Ragunathan Sudarshan , Quarles C. , Prigatano George , Stokes Ashley
Published: August 2023

Functional connectivity, measured with BOLD-fMRI, has been previously used to study changes in aging and Alzheimer’s disease. A combined spin- and gradient-echo (SAGE) acquisition may be able to more sensitively distinguish between disease-related changes in functional connectivity. Therefore, this study aims to implement SAGE in resting-state fMRI to assess differences between macro- and microvasculature-sensitive data, between SAGE maps and single-echo methods, and between healthy aging and cognitively impaired cohorts’ functional networks.
A Transceiver Coil for improved in ovo Imaging of the Chorioallantoic Membrane at 7T
Authors: Mahmutovic Mirsad , Shrestha Manisha , Poniatowski Matthäus , Jedelská Jarmila , Bakowsky Udo , König Alexander , Mahnken Andreas , Keil Boris
Published: August 2023

The chorioallantoic membrane (CAM) model is a simple and low-cost model that allows screening of a large number of pharmacological samples. It is used in preclinical research as an intermediate step between in vitro and in vivo experiments and does not require approval by the animal experiment ethics committee. Latest studies show that MRI is a suitable imaging modality for evaluating drug delivering systems with the CAM-model. However, appropriate hardware for high-resolution MR imaging of the CAM model is still missing. To fill this gap, we designed, constructed, and evaluated a transceiver solenoid coil for in ovo imaging at 7T.
Multi-contrast Multi-scale vision Transformers (MMT) for MRI Contrast Synthesis
Authors: Liu Jiang , Venkata Srivathsa Pasumarthi , Datta Keshav
Published: August 2023

Complementary information from multi-modal MRI is widely used in clinical practice for disease diagnosis. Due to scan time limitations, image corruptions, and different acquisition protocols, one or more contrasts may be missing or unusable. Recently developed CNN models for contrast synthesis are unable to capture the intricate dependencies between input contrasts and are not dynamic to the varying number of inputs. This work proposes a novel Multi-contrast and Multi-scale vision Transformer (MMT) that can take any number and combination of input sequences and synthesize the missing contrasts.
A Least-squares Method for Improved Sensitivity Map Estimation when Imaging X-Nuclei
Authors: Dwork Nicholas , Tang Shuyu , Larson Peder , Gordon Jeremy
Published: August 2023

We present a least-squares method for estimating sensitivity when imaging x-nuclei. We show results with hyperpolarized pyruvate in both the heart and the brain.
Synchronizing TMS pulses for free artifact fMRI for multichannel TMS systems using the integrated whole head TMSMR 28 channel RF coil array
Authors: de Lara Lucia Navarro , Uluc Isil , Meng Qinglei , Stockmann Jason , Wald Larry , Nummenmaa Aapo
Published: August 2023

For TMS/fMRI experiments, to acquire functional images without artifacts, general recommendations have been proposed. In order to apply TMS pulses in a multichannel Transcranial Magnetic Stimulation system integrated with the new constructed TMSMR 28- channel RF coil, we have explored the different options and artifacts that can be generated depending on when the TMS pulses are applied with respect to the sequence timing. As conclusion, we propose a method using an RF pick up loop to assure that the delivery of the TMS pulses are not close to the EPI navigators or the imaging gradients.
Estimation of cellular water exchange rate, intracellular volume fraction and longitudinal relaxation time in cancer cells
Authors: Kiser Karl , Zhang Jin , Kim Gene
Published: August 2023

The T1 recovery curves of cells may be sensitized to water exchange when suspended in solution with gadolinium-based contrast agent. The non-monoexponential recovery curves are fitted to a two-site exchange model to estimate the water exchange rate. This estimation process requires the inclusion of relevant parameters such as volume mol fraction and intracellular relaxation time, cannot be accurately estimated from a single curve. Here, we propose a multiple curve fitting approach, which infuses the model with additional information. By modelling multiple recovery curves of samples in a titration of GBCAs, we demonstrate an accurate and robust method for measuring invitro water exchange, volume mol fractions and intracellular relaxation rate.

The T1 recovery curves of cells may be sensitized to water exchange across the cell membrane when suspended in solution with gadolinium-based contrast agent. The two-compartment model fitting requires the inclusion of relevant parameters such as volume mol fraction and intracellular relaxation time but cannot be accurately estimated from a single curve. Here, we propose a multiple curve fitting approach, which infuses the model with additional information. By modelling multiple recovery curves of samples in a titration of GBCAs, we demonstrate an accurate and robust method for measuring invitro water exchange, cell volume and intracellular relaxation rate.
Reducing streak artefacts in radial MR fingerprinting of the prostate through automated channel removal
Authors: Sørland Kaia , Trimble Cristopher , Sandsmark Elise , Bathen Tone , Elschot Mattijs , Cloos Martijn
Published: August 2023

The extreme undersampling factors used in radial magnetic resonance fingerprinting (MRF) of the prostate lead to strong streak artefacts from the femoral arteries and veins. However, it turns out that only a subset of receiver channels is responsible for these streaks. In this work we automatically detected and removed these from the reconstruction pipeline. The method was applied to MRF acquired with various acceleration factors in seven asymptomatic volunteers, significantly reducing visible streaks in reference tissues surrounding the prostate without impairing the prostate T1 and T2 values in the MRF maps.
Spectral principal axes system (SPAS) and tuning of tensor-valued encoding for time-dependent anisotropic diffusion
Authors: Lasič Samo , Just Nathalie , Lundell Henrik
Published: August 2023

Tensor-valued diffusion encoding can be confounded by time-dependent diffusion (TDD). Matching sensitivity to TDD or tuning of b-tensors with different shapes is needed for unbiased microstructure assessment. We present a method for tuning linear tensor encoding (LTE) to spherical tensor encoding (STE), which could be optimized for different hardware constraints. Furthermore, we introduce the spectral principle axes system (SPAS), representing spectral anisotropy of STE. The SPAS LTEs could provide an alternative to tuning and enable disentangling effects of microscopic anisotropy and TDD, useful to correlate cell shape and size.
Suppression of extracranial lipids in short TE STEAM of the human brain at 7T with an external crusher coil
Authors: Wiegers Evita , Bhogal Alex , Jacobs Sarah , Gosselink Mark , Prompers Jeanine , Klomp Dennis
Published: August 2023

Short TE STEAM is an appealing MRS sequence especially for the quantification of low-concentration J-coupled spin systems. However, in comparison to sLASER, STEAM is associated with larger chemical shift displacement errors in all three directions. With an inhomogeneous B1+-field, slice profiles degrade, resulting in artefacts from extracranial lipids. Here we demonstrate that lipid artefacts can be removed through the use of an external crusher coil. Without use of the crusher coil, large extracranial lipid artefacts are present when selecting a large voxel. Upon activation of the crusher coil, these signals are eliminated, yielding 1H spectra free of large baseline distortions.
Time-efficient and reproducible relaxation measurements by 31P-MR fingerprinting in human brain at 7T
Authors: Widmaier Mark , Lim Song-I , Xin Lijing
Published: August 2023

In this abstract, we report the reproducibility of the new 31P-MRF technique on healthy volunteers. We show that relaxation and concentration rates can be estimated fast and accurate in good agreement with state-of-the-art methods in the human brain and in phantoms at 7T. This novel efficient technique is able to achieve a 5-fold acquisition time reduction of 31P relaxation parameter measurements, using only 6 min scan time.
Effects of Intersubject Differences on Scattering Parameters, SAR, and B1+ in a 7T 8ch. Head Coil
Authors: Hardy Benjamin , Banik Rana , Yan Xinqiang , Anderson Adam
Published: August 2023

Shorter wavelengths and higher frequencies at UHF contribute to complicated electric field distributions and higher power absorption in the human head leading to potential safety concerns. Scattering parameters, local and global SAR, and B1+ fields are calculated in an 8-channel surface loop Tx array simulated over 70 head-and-shoulder models of 10 tissue compartments. RF shimming methods and pulse sequences are analyzed over each model to demonstrate local and global SAR variation in a population. Patient proximity, coil loading and design, patient composition, and RF shim weights contribute to the variations in SAR and B1+ experienced by each subject.
Correction Factor for EPT-based Patient-Specific SAR Maps
Authors: Martinez Jessica , Arduino Alessandro , Bottauscio Oriano , Zilberti Luca
Published: August 2023

Specific absorption rate (SAR) values can be obtained using MRI data to calculate the electrical conductivity via Electric Properties Tomography (EPT) and by indirectly obtaining the electric field by the B1+ field. However, only using B1+ will result in incorrect SAR values. In this work, we propose the calculation of a tissue-specific correction factor to mitigate the inaccuracy of SAR.
A 16-channel transceiver dipole array for 1H body imaging at 10.5T: Validation and VOP enabled imaging in-vivo
Authors: Schmidt Simon , Erturk Arcan , He Xiaoxuan , Eryaman Yigitcan , Metzger Gregory
Published: August 2023

To realize the increased pTx functionality of a 16-channel transceiver dipole array for body imaging at 10.5T, a validation process was implemented. After quantifying the uncertainty of the RF arrays electromagnetic simulations a total safety factor was determined enabling the implementation of real-time local SAR monitoring on the scanner through use of virtual observation points (VOP). In vivo data was acquired with the VOP enabled power monitoring demonstrating local RF shimming performance with and without local SAR constrained optimizations.
Comparison of the reproducibility of human renal amide proton transfer weighted imaging in axial and coronal orientations
Authors: Wang Xia , Du# Zeliu , Tian Gang , Jiang Yu , Bu Chaoqun , Zhao Na , Yu Chanjuan , Han* Yuedong , Yue Xiuzheng , Shen Zhiwei
Published: August 2023

Three-dimensional (3D) amide proton transfer (APT)-weighted (APTw) techniques have been applied in clinical work, However, image quality and feasibility of APTw imaging in normal kidneys at different scanning orientations have not been well confirmed. This study conducted on 27 healthy adult volunteers and all volunteers underwent intermittent end-respiratory breath-holding of axial and coronal 3D-APTw imaging. The preliminary results of this study show that the image quality of the image quality of renal APTw axial plane is better than that of coronal plane, and the reproducibility of APTw measurement values in axial plane is superior to that of coronal plane.
Evaluation of microsatellite instability in endometrial cancer using APTw combined with IVIM MR imaging
Authors: Ma Changjun , Liu Ailian , Tian Shifeng , Chen Lihua , Wang Nan , Song Qingwei , Shen Zhiwei
Published: August 2023

Testing of Microsatellite Instability (MSI) is used to evaluate the prognosis of endometrial cancer (EC) to make the optimal treatment, and plays an important role to screen for Lynch syndrome. MSI had been detected by the traditional technology, such as PCR, IHC and Next Generation Sequencing（NGS）, however, MSI also could be assessed using magnetic resonance imaging with the advantages of non-invasion and low-cost. This study aimed to investigate the clinical value in assessing the status of EC MSI with amide proton transfer weighted (APTw) imaging and intravoxel incoherent motion (IVIM) diffusion MR imaging.
Searching for an MR Fingerprinting sequence to measure brain oxygenation without contrast agent
Authors: Coudert Thomas , Delphin Aurélien , Warnking Jan , Lemasson Benjamin , Barbier Emmanuel , Christen Thomas
Published: August 2023

We propose to use numerical simulations and Monte Carlo approaches to test 40 MR fingerprinting sequences for their ability to quantify the BOLD effect and provide maps of baseline blood oxygen saturation without the need for contrast agent injection. Our results suggest that several sequences can produce SO2 maps with less that 3% error on average even in the presence of B1 and B0 inhomogeneities. T2 and blood vessel radius could also be estimated with the same acquisitions.
Accuracy and repeatability of joint sparsity multi-component estimations in MR Fingerprinting
Authors: Nagtegaal Martijn , Nunez-Gonzalez Laura , Poot Dirk , de Bresser Jeroen , van Osch Thijs , Tamames Juan Hernandez , Vos Frans
Published: August 2023

Multi-component MR Fingerprinting estimations with Sparsity Promoting Iterative Joint Non-negative least squares (SPIJN-MRF) provide the possibility to obtain partial volume tissue segmentations and myelin water maps. We evaluated the accuracy and repeatability of SPIJN-MRF estimations in simulations and 5 subjects, scanned 8 times. The obtained segmentations were compared to segmentations from SPM12 and FSL. In simulations, SPIJN-MRF showed the highest accuracy in total volume and voxel-wise measures. In vivo, higher variation was observed with SPIJN-MRF than with SPM12 and FSL, especially in WM and GM. In conclusion, SPIJN-MRF provides accurate and precise tissue relaxation parameter estimations with partial volume estimations.
Deep-learning based brain tumor segmentation using quantitative MRI
Authors: Tampu Iulian , Blystad Ida , Haj-Hosseini Neda , Eklund Anders
Published: August 2023

Manual annotation of gliomas in magnetic resonance (MR) images is a laborious task, and it is impossible to identify active tumor regions not enhanced in the conventionally acquired MR modalities. Recently, quantitative MRI (qMRI) has shown capability in capturing tumor-like values beyond the visible tumor structure. Aiming at addressing the challenges of manual annotation, qMRI data was used to train a 2D U-Net deep-learning model for brain tumor segmentation. Results on the available data show that a 7% higher Dice score is obtained when training the model on qMRI post-contrast images compared to when the conventional MR images are used.
Study of Subjective Tolerance during 5T Whole-Body MRI Examinations
Authors: Zhu Xuchen , Sun Wenbo , Zhu Shuo , Shen Zhenhua , Lan Lan , Han Shihong , Zhang Shuheng , Shi Zhang , Liu Qi , Ye Yongquan , Liang Liang , Xu Haibo , Liu Liang
Published: August 2023

Questionnaires on subjective feeling were collected and analyzed from 202 subjects following whole-body MRI examinations at 5T. No intolerable discomfort was reported, indicating whole-body examinations at 5T is safe when necessary safety protocols were followed.
Brain-wide Quantitative Imaging Measures in progressive Multiple Sclerosis: a Multi-modal Framework and Longitudinal Validation Study
Authors: Zou Yukai , Varatharaj Aravinthan , Stuart Charlotte , Lennartsson Finn , Darekar Angela , Wheeler-Kingshott Claudia , Galea Ian
Published: August 2023

This study aims to develop quantitative MRI measures that are more statistically straightforward to correlate with clinical disability of progressive MS individuals, whose brains often show atrophy and tissue damage that vary amongst regions, which is hard to interpret clinically. The impacts of different software packages and MR contrasts on estimating brain atrophy were investigated. Individual DTI profiles characterised specific progression within each brain region, preserving the heterogeneity amongst individuals. Some of the measures were shown to capture the overall progression and correlate with clinical disability. In summary, this framework shows promise to integrate quantitative MRI into routine clinical care.
Diagnosing Parkinson’s disease by Combining Neuromelanin and Iron Image Features Using Automatic SN Subregions Detection Approach
Authors: Jin Zhijia , Jokar Mojtaba , Wang Ying , Li Yan , Cheng Zenghui , Liu Yu , Tang Rongbiao , Shi Xiaofeng , Zhang Youmin , Min Jihua , Liu Fangtao , He Naying , Haacke E. Mark , Yan Fuhua
Published: August 2023

A total of 100 Parkinson’s disease (PD) patients and 100 age- and sex-matched healthy controls (HCs) were scanned using a single 3D gradient echo magnetization transfer sequence. We developed an automatic substantia nigra (SN) subregions segmentation approach to get neuromelanin (NM) and iron measurements in the SN. These measures along with their overlap region volume and the nigrosome-1 (N1) sign showed reliable results indicative of promising diagnostic biomarkers to differentiate PD patients from HCs.
Machine Learning-Based Contrast Enhanced T2-FLAIR Radiomics method for predicting IDH1 Genotype of Diffuse Gliomas
Authors: Bao Han , Lu Yi , Zhao Qirui , Hou Zujun , Chen Liuyang , Xie Wei , Wang Qing , Zhao Wei , Koh Tong-San , Nie Lisha , Li Zongfang
Published: August 2023

The current study aims to build isocitrate dehydrogenase 1 (IDH1) genotype prediction models based on selected radiomics features derived from contrast-enhanced T2 fluid attenuated inversion recovery (CE-T2-FLAIR) in predicting IDH1 genotype of diffuse gliomas. Radiomics features from CE-T2-FLAIR images go a step further to enrich the content of MRI-based radiomics. It was concluded that machine learning-based radiomics of CE-T2-FLAIR could efficiently predict the IDH1 genotype of diffuse gliomas.
Quality control and nuisance regression of fMRI, looking out where signal should not be found
Authors: Provins Céline , Markiewicz Christopher , Ciric Rastko , Goncalves Mathias , Caballero-Gaudes Cesar , Poldrack Russell , Hagmann Patric , Esteban Oscar
Published: August 2023

Quality control of functional MRI data is essential as artifacts can have a critical impact on subsequent analysis. Yet, visual assessment of a dataset is tedious and time-consuming. By extending the carpet plot with the voxels located on a closed band (or “crown”) around the brain, we showed that fMRI data quality can be assessed more effectively. This new feature has been incorporated into MRIQC and fMRIPrep. In addition, a new nuisance regressor has been added to the latter, calculated from timeseries within this new “crown”.
SynthStrip: skull stripping for any brain image
Authors: Hoopes Andrew , Mora Jocelyn , Dalca Adrian , Fischl* Bruce , Hoffmann* Malte
Published: August 2023

The removal of non-brain signal from MR data is an integral component of neuroimaging streams. However, popular skull-stripping utilities are typically tailored to isotropic T1-weighted scans and tend to fail, sometimes catastrophically, on images with other MRI contrasts or stack-of-slices acquisitions that are common in the clinic. We propose SynthStrip, a flexible tool that produces highly accurate brain masks across a landscape of neuroimaging data with widely varying contrast and resolution. We implement our method by leveraging anatomical label maps to synthesize a broad set of training images, optimizing a robust convolutional network agnostic to MRI contrast and acquisition scheme.
Identifying perfused tissue regions through IVIM and ADC model comparison: technical validation
Authors: McHugh Damien , Dubec Michael , Price James , Moore Chris , Buckley David , O'Connor James , Thomson David , McPartlin Andrew
Published: August 2023

Intravoxel incoherent motion (IVIM) can provide information about tissue perfusion in tumours and organs at risk, but the model may not be applicable in all voxels in a region of interest. Here, a model comparison framework is developed, based on comparing IVIM and apparent diffusion coefficient model fits, aiming to identify perfused voxels and quantify the proportion of tissue containing a perfusion component, pIVIM. Technical validation of the framework is performed, with simulations and phantom data showing that SNR and diffusion properties can bias pIVIM, while in vivo parotid gland data show that pIVIM exhibits good repeatability.
Quantitative Magnetization Transfer parametric mapping unbiased by on-resonance saturation and dipolar order contributions
Authors: Soustelle Lucas , Troalen Thomas , Hertanu Andreea , Guye Maxime , Ranjeva Jean-Philippe , Varma Gopal , Alsop David , Girard Olivier , Duhamel Guillaume
Published: August 2023

Two major biases in the current qMT methodology arise from i) on-resonance saturation effects induced by readout pulses used in variable flip angle SPGR experiments, and ii) dipolar order effects induced by single-frequency off-resonance saturation pulses leading to a reduced saturation efficiency. In this work, we evaluate these two biases by performing experiments and analyses by accounting for on-resonance saturation in the qMT model and using simultaneous symmetric dual-offset frequency saturation pulses to cancel out dipolar order effects. Results show improvement in the fitting procedure and more accurate estimation of T1,f and MPF values in white and grey matter structures.
FAR-CEST: Fast Acquisition and Reconstruction for Chemical Exchange Saturation Transfer (CEST) imaging using a Deep-Learning Approach
Authors: Liu Chuyu , Chen Zhensen , Chen Yibing , Chai Xubin , Li Zhongsen , Song Xiaolei
Published: August 2023

We developed a Fast Acquisition and Reconstruction CEST (FAR-CEST) method at 3T human scanners, based on a deep learning approach. A 10X accelerated acquisition was achieved, which under-sampled K-space using a randomized Cartesian pattern of variable density. To fully utilize the correlation among saturation offset dimension, especially to compensate for sparsely-sampled K-space edge, a 3D-Res-Unet model was trained for reconstruction. Results on healthy adult brain suggested that FAR-CEST can produce high quality saturation-weighted images and Z-spectra，but the CEST contrast slightly altered. The highly-acceleration feature of FAR-CEST has been initially validated, yet still require improvement on reconstruction accuracy.
Large-scale simulations to create large collections of realistic white matter samples using MEDUSA
Authors: Brullé Alexis , Bachiri Anas , Destrieux Christophe , Wiber Gilles , Delzescaux Thierry , Uszynski Ivy , Poupon Cyril
Published: August 2023

In this work, we demonstrate that the MEDUSA simulator can be used to create huge collections of brain white matter tissue microstructure samples in the frame of large-scale HPC simulation campaigns and how these Big Data could serve the design of novel computational models able to decode white matter microstructure.
Fabrication of an Anthropomorphic, In-Vitro Liver Flow Phantom for Use in Motion-Robust MRI Sequence Validation Experiments
Authors: Rice James , Geng Ruiqi , Hernando Diego , Roldan-Alzate Alejandro
Published: August 2023

A major limitation of standard diffusion-weighted imaging (DWI) in the various organs, including the liver, is the presence of artifacts, bias, and poor reproducibility resulting from physiologic cardiovascular-induced motion. Recent efforts to develop motion-robust DWI sequences show promise, but there is an important unmet need for highly controlled validation in motion phantoms. This study presents the fabrication of an anthropomorphic liver flow phantom that can produce compressive motion in the liver to generate and control artifact seen in DW images. This phantom may enable improved validation of motion-robust DWI and other motion-robust applications.
ASSESSMENT OF TREATMENT RESPONSE TO DC VACCINE IN RECURRENT GBM PATIENTS USING MULTIPARAMETRIC MRI PREDICTION MODEL
Authors: de Godoy Laiz , Wang Sumei , Asadollahi Shadi , Nasrallah MacLean P. , O’Rourke Donald M. , Brem Steven , Desai Arati , Loevner Laurie , Mohan Suyash , Chawla Sanjeev
Published: August 2023

The highly aggressive nature of glioblastoma (GBM) leads to a dismal prognosis, and alternative therapies are being sought. Immunotherapy, such as the Dendritic Cell (DC) vaccine, is currently being evaluated for recurrent GBMs in clinical trials. Follow-up imaging after this immunotherapeutic approach often mimics disease progression on conventional images, making standard MRI evaluation challenging. Our findings indicate that our previously established multiparametric MRI-based prediction model has the capacity to accurately assess response to DC vaccine in recurrent GBM patients, objectively characterizing as either TP or PsP GBM patients, avoiding interruptions in satisfactory treatments, and preventing invasive procedures in PsP cases.
Preclinical platform for the identification of deuterium magnetic resonance spectroscopy-based biomarkers of tumor metabolism
Authors: Batsios Georgios , Tran Meryssa , Taglang Celine , Gillespie Anne Marie , Ronen Sabrina , Costello Joseph , Viswanath Pavithra
Published: August 2023

Metabolic reprogramming is a fundamental hallmark of cancer, which can be exploited for non-invasive tumor imaging. Deuterium magnetic resonance spectroscopy (2H-MRS) recently emerged as a novel, clinically applicable method of non-invasively monitoring flux from 2H-labeled substrates to metabolic products. However, to date, preclinical studies have been performed in vivo, an endeavor that suffers from low-throughput and potential waste of animal lives, especially in treatment response studies. Here, we demonstrate the ability to quantify metabolism of 2H-MRS probes in live cell suspensions. Our studies will expedite the identification of novel 2H-MRS probes for imaging brain tumors and potentially other cancers.
MRI Monitoring of Therapeutic Efficacy of Novel Heme targeting drugs in Non-small cell lung cancer (NSCLC) Orthotopic Tumors in Mice
Authors: Liu Li , Yang Donghan , Wansapura Janaka , Hao Guiyang , Mason Ralph P. , Zhang Li
Published: August 2023

The goal was to evaluate the activity of two novel heme targeting drugs in Non-Small Cell Lung Cancer models using multi-modality imaging. We found that the novel heme targeting drugs CycT (cyclopamine tartrate) and HSP2 (heme-sequestering peptide 2) were effective in suppressing NSCLC lung tumor growth as assessed by multimodality imaging and confirmed by pathology/histology. MRI detected the H1395 and H1299 orthotopic xenografts and was correlated with PET studies and histology.
Magnetic resonance mapping with calculation of extracellular volume fraction allows for a reliable assessment of liver cirrhosis severity
Authors: Mesropyan Narine , Kupczyk Patrick , Dold Leona , Praktiknjo Michael , Chang Johannes , Isaak Alexander , Endler Christoph , Kravchenko Dmitrij , Bischoff Leon , Sprinkart Alois , Pieper Claus , Kuetting Daniel , Jansen Christian , Attenberger Ulrike , Luetkens Julian
Published: August 2023

Assessment of disease severity in patients with liver cirrhosis is of great clinical importance and allows outcome prediction and overall mortality risk estimation. In the present study, we investigated the diagnostic utility of MRI-derived extracellular volume fraction (ECV) for the assessment of liver cirrhosis severity and differentiation between different Child-Pugh classes. Our study results demonstrated a high diagnostic performance of ECV for the assessment of liver cirrhosis severity and offer a reliable discrimination between different Child-Pugh classes. ECV might be a new quantitative marker for the assessment of liver cirrhosis severity, which can be calculated from quantitative liver MRI.
Liver response to fasting and isocaloric high-carbohydrate refeeding in lean and obese women
Authors: Sedivy Petr , Dusilova Tereza , Setinova Barbora , Dezortova Monika , Burian Martin , Krauzova Eva , Siklova Michaela , Rossmeislova Lenka , Koc Michal , Hajek Milan , Kovar Jan
Published: August 2023

Our MRS and MRI study investigates the liver response to two days of fasting followed by two days of isocaloric high carbohydrate refeeding in lean and obese women. Hepatic fat content increased after fasting in lean women whereas it did not change in obese women. The tendency to lose or accumulate fat during fasting could be related to the overall initial hepatic fat content. Moreover, liver volume significantly decreased and increased during fasting and refeeding, respectively.
Ginkgo: a novel modular and and Open Source MRI pulse sequence development framework dedicated to MRI systems
Authors: Artiges Anaïs , Mauconduit Franck , Uszynski Ivy , Mulot Baptiste , Chaillou Elodie , Ciuciu Philippe , Poupon Cyril
Published: August 2023

We created a new object-oriented environment for MR pulse-sequence development based on IDEA VE11C and above versions using an Open Science philosophy. This Ginkgo toolkit uses a modular structure to facilitate the design of pulse sequences using the aggregation of basic open-source sequence blocks available from the toolkit. Proofs of concept of the productivity gain reached using Ginkgo are provided through the implementation of a series of sequence models including a diffusion-weighted PGSE 3D EPI sequence.
A Software Tool for Inline Post-processing and Visualization of Chemical Exchange Saturation Transfer (PV-CEST) on 3T Scanner
Authors: Liu Chuyu , Wang Yishi , Chen Zhensen , Zhang Yajing , Song Xiaolei
Published: August 2023

We developed a real-time software for CEST post-processing and visualization on Philips 3T scanner, termed as PV-CEST. PV-CEST runs in the vendor provided PRIDE 2.0 environment, providing image view, Z-spectra analysis and quantitative maps calculation functionalities during scanning procedure, which could have great clinical utility.
Test-retest and inter-vendor variability of brain segmentation using 3D synthetic MRI in volunteers at 3T
Authors: Naeyaert Maarten , Vanderhasselt Tim , Raeymaekers Hubert
Published: August 2023

Six volunteers were scanned two times on two different 3T scanners (GE, Philips) using the 3D-QALAS sequence. The intracranial and brain parenchymal volume and myelin content were determined and the brain segmented in cerebrospinal fluid and white and grey matter using synthetic MRI. Bland-Altman plots, Dice coefficient and coefficient of variation indicate that the test-retest variability is very small, but there is an inter-vendor bias for CSF, GM and WM. MyC, BPV and ICV have only a very limited inter-vendor bias. At least for GM and BPV, the expected inter-scanner variation, besides the bias, is below the clinically relevant threshold.
In vivo metabolic CEST changes in brain tumors in a model of metastatic breast cancer
Authors: Lefeuvre Jennifer , MacKey Katie , Tu Tsang-Wei , Frank Joseph
Published: August 2023

Metabolic changes may occur earlier and/or may help distinguish different type of tumors. We investigated the metabolic changes using CEST MRI and characterized induced metastatic breast cancer in the brain of 10 nude rats. In vivo CEST MRI were performed at 9.4T on 3 slices with 31 frequency offsets to cover the full Z-spectra. A total of 12 tumors were analyzed for CEST signal changes. Different tumor types (solid tumor vs necrosis) showed different metabolites uptakes. Tumors located within the dentate gyrus showed significant increased values compared to the tumors in brainstem, cortex and hippocampus.
Improving clinical 3T Amide Proton Transfer weighted contrast in Brain Tumors by using a novel spatial denoising method
Authors: Romdhane Feriel , Longo Dario Livio , Papageorgakis Christos , Firippi Eleni , Mancini Laura , Bisdas Sotirios , Zaiss Moritz , Casagranda Stefano
Published: August 2023

Amide Proton Transfer weighted (APTw) imaging is a promising MR molecular technique for characterizing brain tumors on clinical 3T scanners. However, improving the APT weighted contrast is crucial to translate this approach to clinical practice. In this work we investigated a novel spatial denoising filter in synthetic and clinical APTw data of brain tumor patients.
Healthy vs pathological tau can be differentiated by CEST NMR
Authors: Yu Fang , Ratnakar James , Brewer Jonathan , Hitt Brian , Sherry A Dean , Vinogradov Elena
Published: August 2023

Alzheimer’s Disease (AD) is defined biologically by the presence of neuritic plaques composed of amyloid-in β (Aβ)peptides and dystrophic neurites, neurofibrillary tangles (NFTs) of hyperphosphorylated tau protein, and neuronal loss. In this study, CEST experiments were performed on purified full-length tau monomer and aggregated tau fibrils. We found differences in CEST z-spectra between purified full-length tau monomers and aggregated tau fibrils. This finding substantiates the potential use of CEST for ultimately monitoring disease progression in AD patients
Octopus rubescens as a model for the development and validation of muscle DTI tractography
Authors: Naughton Noel , Ciobanu Luisa , Majumdar Shreyan , Gazzola Mattia , Sutton Brad
Published: August 2023

We present data from a pilot study of an Octopus rubescens arm demonstrating it is possibly to identify the complex structural arrangement of its musculature using MRI and DTI tractography. All major muscle groups of the octopus arm are able to be identified and extracted using DTI tractography. Overall, this pilot study establishes cephalopod arms as an appealing testbed for the development of muscle MRI segmentation and tractography algorithms.
Separation of Intra- and Extra-cellular Sodium Using A Rotation of Spiral Disc (RSD) Sequence with Multiple Echoes
Authors: Jung Kwan-Jin , Fang Hsin-Yu , Wilund Kenneth , Sutton Brad
Published: August 2023

An efficient sequence to acquire sodium image, i.e., rotation of the spiral disc, was developed last year. This sequence is further developed to separate the sodium signal into intra- and extra-cellular sodium by collecting multiple echoes and bi-exponential curve fitting. This method is confirmed on agarose phantom for T2* mapping and on human lower-leg muscle with an isometric plantar flexion exercise for separation of intra- and extra-cellular sodium. In the calf muscle experiment, it was found that the intracellular sodium was increased more than the extra-cellular sodium. This method finally allows studying separately the intra- and extra-cellular sodium in muscles.
Investigation of multiplexed sensitivity encoding diffusion-weighted imaging (DWI) in cervical carcinoma:comparison with conventional DWI
Authors: Meng Tiebao , Zhang Weijing , He Haoqiang , Liu Huiming , Xu Guixiao , Zhu Fengting , Qian Long , Xie Chuanmiao
Published: August 2023

MUSE provides significantly better image quality in CC compared with C-DWI, with no significant difference in ADC.