bluuebunny/crossref_metadata_2025 huggingface dataset:
TR effect on Myelin Water Imaging
Authors: Zhang Jing , Banerjee Suchandrima , MacKay Alexander
Published: August 2024

Myelin water fraction (MWF) is conventionally measured using the T2 decay curve. For a spin-echo based sequence, the repetition time (TR) is limited by SAR. Most MWF studies have been carried out at 3T; but a 1.5T system has lower power deposition, which enables MWF imaging at lower TRs. Shorter TR will also reduce the total scan time. In this work, we performed myelin water imaging on a 1.5T system to investigate the effect of shorter TR on this technique. This work demonstrated increased MWF in human brain in vivo with decreasing TR.
Effects of aquaporin-4 on neurovascular coupling and brain network in Alzheimer’s disease mice model
Authors: Li Jing , Liu Renyuan , Lv Pin , Zhang Bing
Published: August 2024

Neurovascular uncoupling can be found in the early stage of AD continuum. The effect of AQP4 content on neurovascular coupling (NVC) in AD mice is unclear. Adult 5xFAD mice and wild-type mice were employed in this study. Mice received TGN-020, an AQP4 inhibitor, intraperitoneally. The results showed that 20 min after the injection of TGN-020, reduced ReHo in the basal area of the frontal lobe, a trend of reduced functional connectivities and disordered network properties were found among the AQP4-inhibited WT and 5xFAD mice. Therefore, Inhibition of AQP4 may reduce the NVC, and disorder the functional network.
ROI-dependence in clarifying metabolic connectivity mapping within default-mode network using simultaneous FDG PET and BOLD-based fMRI
Authors: Yeh Tzu-chen , Cheng Chou-ming , Chou Chi-che
Published: August 2024

Metabolic connectivity mapping (MCM) is a unique application of simultaneous PET/fMRI for solving the effective connectivity (EC) of brain circuits. Reproducibility of MCM was critical after the initial report. By applying the released database of MONASH (Melbourne, Australia), consistent EC among bilateral inferior parietal lobules (IPL) and posterior cingulate cortices (PCC), as nodes within default mode network (DMN), was identified using MCM with the statistic-based approach. One-way EC using dedicated ROI (regions of interest) derived from grouped ICA (independent component analysis) outperformed the atlas-based ROIs of DMN.
Brain connectome-based imaging markers for identifiable signature of migraine with and without aura
Authors: Fu Tong , Gao Yujia , Huang Xiaobin , Zhang Di , Liu Lindong , Yin Xindao , Wu Xinying , Lin Hai , Dai Yongming
Published: August 2024

In comparison with migraine without aura (MwoA), migraine with aura (MwA) has its own characteristics in symptom, pathological mechanism, treatment and prognosis. In this study, we conducted connectome-based analysis to capture brain connectivity markers that would show identifiable signature of MwA and MwoA, using diffusion tensor imaging and resting-state functional MRI. We found that the alterations of structural and functional connectivity strength contributed to migraine patient subtyping. The whole brain connectome-based imaging markers might provide possible evidence in understanding the heterogeneity of migraine with aura and help for patient-specific decision.
DTI reveals altered structural connectivity of pain-associated regions in a genetic variant of small fiber neuropathy
Authors: Drenthen Gerhard , Far Amir , Faber Catharina , Upadhyay Jaymin , Linden David , van Gool Raquel , Backes Walter , Hoeijmakers Janneke , Jansen Jacobus
Published: August 2024

Patients with small fiber neuropathy (SFN) suffer from chronic pain, which may lead to cerebral changes. Here, we studied structural network changes in idiopathic- and genetic-SFN compared to controls using diffusion-MRI. We found that for the genetic-SFN group pain-associated regions take a more prominent place in the network (in terms of nodal importance). Furthermore, in the genetic-SFN group, a higher nodal importance of pain-associated regions related to lower self-reported pain. This shows that genetic-SFN has a distinct structural pain pathway, which may be indicative of a compensatory mechanism where the structural organization is altered to inhibit the response to pain.
Rapid transfer function-based transmission field shimming for safe and B1+ artefact free MRI of implantation sites
Authors: Berangi Mostafa , Waiczies Helmar , Niendorf Thoralf
Published: August 2024

Fixation of bone fractures with screws is common clinical practical including follow-up monitoring of the implantation site and of the healing process. MRI-based monitoring can be compromised by tissue heating and transmission field distortion. To overcome this challenge, this work uses parallel transmission using an optimal transmission vector. The proposed approach leverages a single EMF simulation without the implant, while the effect of implant electromagnetic scattered fields are estimated using a transfer matrix. Optimal shim vectors are computed by an optimization process using a multilevel genetic algorithm. Our findings demonstrate the feasibility and performance of the transfer function driven approach.
Workflow proposal to test SAR virtual observation points with convex optimization: application to intersubject variability at 11.7T MRI
Authors: Gras Vincent , Chazel Edouard , Boulant Nicolas , Amadon Alexis , Luong Michel
Published: August 2024

Efficient monitoring of the specific absorption rate (SAR) in parallel-transmission MRI is performed by evaluating the RF power deposition on specific SAR matrices called Virtual Observation Points (VOPs). But given the various sources of uncertainties that occur in practice (head placement, anatomy, precision of the body model to name a few), a challenging task remains to determine a suitable safety margin to be applied on the VOPs to offer a tradeoff between safety and scanning performance. In this work, as a first step towards this, we propose a workflow to tackle this problem for brain imaging at 11.7 Tesla.
Local and Whole-Body SAR in UHF Body Imaging: Implications for Matrix Compression
Authors: Fiedler Thomas , Ladd Mark , Orzada Stephan
Published: August 2024

RF safety of multi-channel transmit arrays is supervised with a set of matrices representing local SAR or whole-body SAR. As transmit arrays for body imaging have characteristics of both volume and local transmit coils, this study evaluates both SAR aspects: local and whole-body SAR. In all evaluated cases, the local SAR limit was reached before the whole-body SAR. Nevertheless, the whole-body SAR matrix can be used to reduce the number of local SAR matrices, reducing memory and computing time.
Temperature rise modelling framework for multiple electrode configurations on parallel transmit systems.
Authors: Sidhu Jagjit , Sakaie Ken , Bhattacharyya Pallab , Lowe Mark
Published: August 2024

Implanted electrodes can induce unsafe heating during MRI. Developing safe MRI protocols can be a burdensome process, involving intensive simulations that are hard to tailor to individual patients. To increase the feasibility of safe imaging of patients with implanted electrodes, we extend previous work, that nulled induced currents when the number of transmitters exceeded the number of electrodes, to account for the case when these are equal or the number of electrodes exceeds the number of transmitters. In such cases, complete nulling (no measured temperature rise) is impossible in all electrodes unless an acceptable induced temperature rise is allowed.
Reducing the number of virtual observation points when utilizing populations of body models
Authors: Kazemivalipour Ehsan , May Markus , Stockmann Jason , Barry Robert , Keil Boris , Wald Lawrence , Guerin Bastien
Published: August 2024

We introduce a VOP compression scheme using “stacked E-fields” followed by the removal of linear redundancies with a positive semi-definite convex optimization problem. This method provides a lower VOP-count at a constant SAR overestimation factor compared to three other approaches when applied to 7 Tesla 8-channel and 16-channel arrays loaded with three body models, each placed at three z-positions. The “stacked E-field” method yielded a compression factor of 0.0124% and 0.0039% for the 8-channel and 16-channel arrays, respectively, and 61% and 6% fewer VOPs than the standard VOP approach that does not remove linear redundancies.
Added Value of Quantitative DCE-MRI in Prediction of Breast Cancer Recurrence Following Neoadjuvant Chemotherapy?
Authors: Thawani Rajat , Gao Lina , Mohinani Ajay , Tudorica Alina , Li Xin , Mitri Zahi , Huang Wei
Published: August 2024

Breast cancer patients treated with neoadjuvant chemotherapy (NACT) are at risk of recurrence depending on clinicopathological characteristics. This preliminary study aimed to investigate the predictive performances of quantitative dynamic contrast-enhanced (DCE) MRI parameters, alone and in combination with clinicopathological variables, for prediction of recurrence in patients treated with NACT. Pre- and post-NACT DCE-MRI parameters performed better than tumor size measurement in prediction of recurrence, whether alone or in combination with clinicopathological variables. Combining post-NACT Ktrans with residual cancer burden and age showed the best improvement in predictive performance with ROC AUC = 0.965.
The application of multiband acceleration technique in temporal diffusion spectroscopy for breast tumor imaging
Authors: Ding Jie , Zhang Zhen , Gu Yajia , Wang Yishi , Yue Xiuzheng , Chen Dazhi , Zhu Rongrong , Ha Ruoshui
Published: August 2024

Both the IMPULSED and MRI-cytometry approaches are based on temporal diffusion spectroscopy (TDS), which connotes the acquisitionof dMRI data with a range of diffusion times expressed in terms of components of a diffusion spectrum. MR cell size imaging is possible with IMPULSED and MRI-cytometry using the theory of TDS. In this study, we proposed to use multiband to accelerate the data acquisition for TDS and compared the IMPULSED quantitative parameters and derivative ADC spectrum for two protocols. Our results showed the consistency in IMPULSED quantitative parameters and ADC calculation for the multiband accelerated protocol with the results without using multiband.
Accelerated DWI with deep learning reconstruction in 3T breast MRI: initial clinical experiences and image quality
Authors: Wilpert Caroline , Schneider Hannah , Neubauer Claudia , Benkert Thomas , Weiland Elisabeth , Strecker Ralph , Reisert Marco , Weiß Jakob , Benndorf Matthias , Bamberg Fabian , Windfuhr-Blum Marisa , Neubauer Jakob
Published: August 2024

This prospective study evaluated image quality features of a novel accelerated DWI with deep learning image reconstruction in 3T breast MRI in a clinical setting in direct comparison to conventional DWI. Deep learning DWI (DL-DWI) shows a drastically shortened acquisition time of 46% compared to standard DWI, while maintaining a high image quality. Even though some image quality features were rated superior in standard DWI, image quality remained good for DL-DWI and lesion conspicuity scores were rated superior for DL-DWI compared to conventional breast DWI. Therefore, DL-DWI seems a feasible technique for accelerated breast DWI.
Fast, isotropic, whole head perfusion imaging using a Spin Echo Rotating In-Out Spiral with velocity selective arterial spin labeling
Authors: Frey David , Fessler Jeffrey , Noll Douglas , Hernandez-Garcia Luis
Published: August 2024

We investigate the performance of a new and efficient k-space sampling scheme that presents several advantages for velocity selective ASL imaging by rotating 2D spirals about the kx and ky axis. This paper compares the new readout to a traditional Stack-of-spirals readout by evaluating SNR for perfusion weighted images and the accuracy of z-scores for ASL FMRI experiments.
Subspace reconstruction of high temporal resolution arterial spin labeling angiography using a kinetic model
Authors: Shen Qijia , Chiew Mark , Wu Wenchuan , Okell Thomas
Published: August 2024

4D combined angiography and perfusion using radial imaging and arterial spin labelling (CAPRIA) allows dynamic angiograms to be reconstructed. However, the current approach uses a relatively long temporal window to ensure sufficient k-space coverage within each frame, resulting in abrupt changes between adjacent frames, and additional artefacts. In this work, we use a kinetic model of the angiographic signal to constrain the reconstruction of highly undersampled data. A subspace reconstruction was developed for compressed representation of signal during reconstruction for computational efficiency. In-vivo results showed smoother variation of the angiographic signal in the temporal dimension compared to the original approach.
Measuring Microvascular Pulsatility with Short Bolus Duration (τ) VSASL
Authors: Chen Conan , Barnes Ryan , Wong Eric , Liu Thomas , Bolar Divya
Published: August 2024

Pulsatile blood flow has been linked to structural damage to the cerebral microvasculature. Previous methods have successfully measured pulsatility in the arteries, but few methods exist to target the microvasculature where the damage is occurring. In this current work, we present a simple theoretical model for CBF pulsatility, apply the model to experimental data acquired in human subjects, and report in vivo microvascular pulsatility using VSASL.
Sensitivity of Bi-Exponential UTE-T2* Mapping to Tendon Laxity
Authors: Goyal Ananya , Barbieri Marco , Mazzoli Valentina , Kogan Feliks
Published: August 2024

Tendon laxity can cause pain and increased injury risk. Quantitative MRI using Ultrashort echo time (UTE) sequences can quantify both short and long T2* water components in tendons. This study evaluates the sensitivity of UTE-T2* mapping with a bi-exponential fit model to tendon laxity, in the Achilles tendon under tension and relaxation. T2*long values seemed to increase as tendon load increased, while T2*short values were the opposite. These changes may be caused by water movement due to loading and changes in fiber orientation due to tendon slackening.
Sodium 23Na-MRI reveals elevated sodium content in lower-extremity skin and adipose tissue in peripheral arterial disease
Authors: Pridmore Michael , Shardelow Emily , Taylor Shannon , Behroozian Adam , Donahue Manus , Sullivan Alex , Beckman Joshua , Crescenzi Rachelle
Published: August 2024

Peripheral artery disease (PAD) is an atherosclerotic occlusive disease that reduces lower-limb perfusion, causes ambulatory dysfunction, and leg pain. Sodium imaging (23Na-MRI) may reveal areas of increased tissue sodium deposition related to the mechanisms of PAD dysfunction. We found that patients with PAD showed increased tissue sodium content in skin, subcutaneous adipose tissue (SAT), and inter-muscular adipose tissue (IMAT) compared to controls. Participants with PAD had lower SAT volume and fat content, arguing against a positive relationship between fat as the mediator of increased tissue sodium. 23Na-MRI may inform PAD mechanisms and is being investigated in response to PAD therapies.
Feasibility study of synthetic MRI in shoulder imaging
Authors: Yabo Ni , Zhaorong Tian , zhijun Wang
Published: August 2024

In this work,we found that the image quality of shoulder synthetic MRI sequence is not comparable to that of conventional image quality, and the scanning time is long, but once scanning can generate multiple sets of quantitative images, T2 mapping of synthetic sequence can provide a new quantitative method for the diagnosis and differential diagnosis of supraspinatus tendon related diseases.
Deep learning-based quantification of white matter hyperintensity applicable to real-world clinical FLAIR images
Authors: Onda Kengo , Chotiyanonta Jill , Uchida Yuto , Li Xin , Mori Susumu , Oishi Kenichi
Published: August 2024

White matter hyperintensity (WMH) in the brain is known to correlate with cognitive prognosis in many diseases; automated quantification tools for WMH have been developed, but most have been used to quantify study data from specific diseases imaged with a single scanning protocol. The low accuracy of these tools when used for clinical data with diverse scan protocols and diseases has been a problem in clinical applications. To overcome this limitation, we developed a deep-learning-based WMH quantification model for real-world clinical FLAIR images with high heterogeneity. The results show the potential of this method as a clinical tool.
Hippocampal sLASER 1H-MRS in cognitively unimpaired elderly: Associations with APOE4, CSF p-tau181 and MR morphometry
Authors: Chen Anna , Gajdošík Martin , Peralta Rosemary , Zheng Helena , Gajdošík Mia , Tordjman Mickael , Zabludovsky Julia , Azad Dishari , George Ajax , Rusinek Henry , Zhang Yuxin , Chen LianLian , Madelin Guillaume , Juchem Christoph , Osorio Ricardo , Kirov Ivan
Published: August 2024

The hippocampus, a vulnerable structure in Alzheimer’s disease progression, is one of the most challenging brain structures for 1H-MRS applications. To examine whether hippocampal metabolic dysfunction in cognitively normal elderly may contribute to disease pathology, we used a validated long-TE sLASER sequence to minimize macromolecular signal contamination and chemical shift displacement errors. We tested whether, after adjusting for age, metabolites were associated with APOE4 genotype, a risk factor for amyloid accumulation; and CSF p-tau181 and left hippocampal volume, indicators of tau burden and neurodegeneration, respectively. The main result was a statistically significant direct correlation between Glx and CSF p-tau181.
Comparability of mcTFI QSM and 2D GRE CMB Detection: Implications for for Alzheimer’s Anti-Amyloid Therapy
Authors: Seth Nikita , Kim Geunwon , Selim Magdy , Thomas Ajith , Filippidis Aristotelis , Wen Yan , Spincemaille Pascal , Wang Yi , Soman Salil
Published: August 2024

Cerebral microbleeds/microhemorrhages (CMB) are used for risk stratification, including for the hemorrhagic complication ARIA-H of Alzheimer’s anti-amyloid therapy. For AD, risk information is based on many trials using 2DGRE technique, which is MRI field and parameter dependent. The use of techniques that better distinguish CMB mimics, like calcifications, is limited by an unclear relationship to 2D GRE CMB depiction. In this study we found the number of CMB candidate lesions between 2D GRE and mcTFI QSM obtained during the same scan session highly correlated, suggesting mcTFI could be used in the management of pathologies evaluating presence and number of CMBs.
Investigation of iron content changes in Alzheimer's disease and mild cognitive impairment using quantitative susceptibility mapping
Authors: Huang Chuan-Bin , Zhang Yong , Deng Ke-Xue , Liu Chang
Published: August 2024

This study investigated iron content changes using Quantitative Susceptibility Mapping (QSM) technique in AD and MCI patients, as compared with normal controls, and correlated iron deposit levels with cognitive scores to assess the clinical values of QSM in the diagnosis of AD and MCI. Bilateral caudate nucleus and right putamen showed significantly increased QSM values in AD and MCI patients as compared to healthy controls. The QSM values of right caudate nucleus correlated with the MMSE scores of AD patients. These results might indicate QSM as the potential biomarker for clinical diagnosis of AD and MCI.
Comparison of MR Spectroscopy of Probable Alzheimer’s Disease and Symptoms of Chronic Traumatic Encephalopathy
Authors: Chen Jessica , Alosco Michael , Liao Huijun , Koerte Inga , Shenton Martha , Stern Robert , Lin Alexander
Published: August 2024

Chronic traumatic encephalopathy (CTE) is widely found in individuals exposed to repetitive head impacts (RHI) in organized contact sports, such as football. Previous findings have determined that there is a distinct deposition of phosphorylated tau (p-tau) in its neuropathology compared to other tauopathies, including Alzheimer’s disease. However, there is a lack of diagnostic criteria that examine later-life neurochemical changes due to long-term neurologic consequences to RHI. This study uses magnetic resonance spectroscopy (MRS) to compare neurochemical markers between participants with probable Alzheimer’s disease and symptomatic chronic traumatic encephalopathy in relation to healthy controls.
SWI and MRSI Unite! Metabolic Insights into Iron Deposition in Relapsing-Remitting MS via 7T Magnetic Resonance Spectroscopic Imaging
Authors: Lipka Alexandra , Bogner Wolfgang , Dal-Bianco Assunta , Hangel Gilbert , Rommer Paulus , Strasser Bernhard , Motyka Stanislav , Hingerl Lukas , Berger Thomas , Leutmezer Fritz , Gruber Stephan , Trattnig Siegfried , Niess Eva
Published: August 2024

Besides clinical examination, conventional T1/T2-weighted magnetic resonance imaging (cMRI) is the method of choice for diagnosis and treatment monitoring of Multiple Sclerosis (MS). In contrast to cMRI, which - in MS - can only depict the severity of irreversible tissue damage and is not able to explain underlying pathological processes, MR Spectroscopic Imaging (MRSI) can detect pathologies on a biochemical level, while Susceptibility Weighted Imaging (SWI) provides information about iron deposition. In 31 relapsing-remitting (RRMS) patients, we investigate - via ultra-high resolution FID-MRSI at 7T - metabolic characteristics of different types of iron accumulation and the metabolic distribution within lesions and their vicinity.
Characterization of Paramagnetic Rim Lesions using quantitative and semi-quantitative MRI modalities
Authors: Tamanti Agnese , Colombi Annalisa , Peloso Angela , Serafin Nicola , Camera Valentina , Pizzini Francesca , Castellaro Marco , Calabrese Massimiliano
Published: August 2024

Chronic active lesions have been recently investigated in multiple sclerosis (MS) and associated with the detection of paramagnetic rims on susceptibility-based MRI images (filtered phase and quantitative susceptibility mapping). Quantitative MRI approaches have the potential to reveal the degree of tissue damage in paramagnetic rim lesions. In this study a significant increase in T2* relaxation time and Quantitative Susceptibility Mapping (QSM) as well as a decrease in Magnetization Transfer Ratio (MTR) and Magnetization Transfer Saturation (MTSat) was revealed in PRL+ lesions compared to PRL-, thus supporting the use of these MRI metrics to detect tissue damage associated with chronic activity.
Disruption of default mode network and salience network dynamics in acute traumatic pain states
Authors: Karunanayaka Prasanna , Mills-Huffnagle Sara , Augusto Corinne , Cauffman Aimee , Hazelton Joshua , Kanekar Sangam , Hobkirk Andréa , Nyland Jennifer
Published: August 2024

Persistent and chronic pain following acute musculoskeletal injury is a significant contributor to diminished quality of life. We correlated self-reported pain using the McGill Pain Questionnaire with resting-state brain network connectivity in patients with blunt chest trauma. Results suggest that both inferior parietal and insular cortex connectivity were positively correlated to greater self-reported pain and a region within the salient network showed a negative correlation. These results support the hypothesis that aberrant functioning of brain circuits that assign salience values to stimuli may contribute to pain perception. Understanding abnormal activity/connectivity may identify targets to prevent persistent and chronic pain.
Brain Micro-Structural and Functional Alterations for Cognitive Function Prediction in the End-Stage Renal Disease Patients
Authors: Zheng Jiahui , Dou Weiqiang , Wu Xiangxiang , Shi Haifeng
Published: August 2024

The goal of this study was to investigate the relationships of altered brain micro-structure and function, and cognitive function for ESRD patients undergoing maintenance hemodialysis. Specifically, diffusion kurtosis imaging (DKI), the resting-state functional connectivity (FC) algorithm, and the least squares support vector regression machine (LSSVRM) were utilized to conduct our study. Brain micro-structural and functional changes were found in ESRD patients, which may account for the onset of cognitive impairment in affected patients. These quantitative parameters combined with our optimized prediction model may be helpful to establish reliable imaging markers to detect and monitor cognitive impairment associated with ESRD.
Aberrant brain gray matter and functional networks topology in end stage renal disease patients with cognitive impairment
Authors: Zheng Jiahui , Dai Jiankun , Wu Xiangxiang , Shi Haifeng
Published: August 2024

This study aimed to characterize the topological properties of gray matter (GM) and functional networks in end-stage renal disease (ESRD) patients undergoing maintenance hemodialysis to provide insights into the underlying mechanisms of cognitive impairment. Functional and GM networks were constructed based on resting-state functional magnetic resonance imaging (rs-fMRI) and diffusion kurtosis imaging (DKI), respectively. Disrupted topological organizations were observed, as indicated by significantly altered global measures, nodal efficiency, and degree centrality, which may account for the progression of cognitive dysfunction. And implementation of prediction models based on neuroimaging metrics may provide more objective information to promote early diagnosis and intervention.
Microstructral and Functional Changes of brain in Pontine Infarction: A Combined Arterial Spin Labeling and Diffusion Tensor Imaging Study
Authors: Chang Peipei , Sun Peng , Miao Yanwei
Published: August 2024

Pontine infarction (PI) is very common in posterior circulation infarction, which can lead to behavioral dysfunctions, such as motor and cognition impairment. However, secondary changes in microstructure after PI in the whole brain remain unclear. This study aimed to explore the changes in cerebral blood flow (CBF) and fractional anisotropy (FA) in PI patients and to better understand the whole brain microstructure changes. We found PI could lead to extensive white matter tracts impairment in most of the whole brain regions and perfusion changes in some brain regions.
Voxel-mirrored homotopic connectivity is impaired in cortical stroke but compensatory in subcortical stroke: a resting-state fMRI study
Authors: Zhao Changjiang , Yu Chengxin , Rao Bo , Pan Junlong , Zhu Li , Chen Jiangjin , Chen Long , Xiong Xiong , Zhang Can , Ye Yong , Wang Zheng , Yang Xiaoling , Xie Lisi , Zhao Xiance , Zhao Chen , Huang Shan
Published: August 2024

The alteration patterns of bi-hemispheric coordination between homologous areas in the whole brain of acute ischemic stroke patients with different infarct sites remains unclear. In the analysis of the voxel-mirrored homotopic connectivity (VMHC) among patients with frontoparietal lesion (G1), radiation coronal lesion (G2) and basal ganglia lesion (G3), VMHC was significantly decreased in G1 compared with G2 and G3. The impaired regions, such as precentral gyrus and postcentral gyrus, were part of the sensorimotor and default mode network. In contrast, VMHC mostly increased in patients with subcortical stroke, which indicates compensation rather than impairment of bi-hemispheric coordination.
Use of Magnetic Materials to Mitigate RF-induced Heating in Active Implantable Medical Devices with 1.5T MRI
Authors: Islam Md Zahidul , Kumar Ananda , Zheng Jianfeng , Chen Ji
Published: August 2024

The effect of ferrite magnetic beads to suppress the induced currents on a straight wire active implantable medical devices (AIMDs) lead was investigated. Leads with one, two and no ferrite beads were studied experimentally and using numerical simulations. The application of ferrite beads on the leads significantly reduced induced currents, and thus heating on experiments outside the MRI scanner. In the MRI magnet no significant reduction in heating was observed due to magnetic saturation of the ferrite beads. Suitable magnetic material for current suppression needs to be developed for application in MRI scanners.
MR conditionality of two MR Conditional DBS ipsilateral implants with separate IPGs
Authors: Aldayeh Louai , Rahman Mizan , Venook Ross
Published: August 2024

Previous investigations of RF-induced heating of multiple implants (active as well as passive) have shown that heating of an implant can be impacted by the presence of a separate neighboring implant. This work assessed to which extend this phenomenon is present for the limited scope of two separate MR Conditional ipsilateral DBS implants, one on one side of the body, and another on the other side. Both, RF-induced heating and voltage injection level into the IPG were assessed. A variety of DBS lead configurations, and clinically relevant distances in-between the two separate implants, were thoroughly assessed for a data-driven conclusion.
Potential anti-HER2 target therapy beneficiaries: can MRI radiomics identify the status of HER2-low in breast cancer?
Authors: Bian Xiaoqian , Yue Zhibin , Du Siyao , Xu Yan , Song Yang , Zhao Min , Zhang Lina
Published: August 2024

Recently, HER2-low expression tumor was proposed as a new entity in the field of breast cancer and radiomics studies related to HER2-low are rare. This study investigated whether multiparametric MRI-based radiomics can distinguish HER2- low from HER2-positive and HER2-zero in breast cancer. Results showed that clinico-radiomics nomograms including hormone receptor status and radiomics signatures combined contrast-enhanced T1-weighted and apparent diffusion coefficient map performed best in both prediction tasks: HER2-positive vs. HER2-negative and HER2-low vs. HER2-zero. This suggests that multiparametric MRI radiomics achieved effective prediction of HER2-low, which might be further guidance of the anti-HER2 targeted therapy in breast cancer.
The Impact of Compressed Sensing on Radiomics of Fast Anatomical MRI of Rat Brain at 7T
Authors: Arpak Arda , Sümer Esra , Samlı Asım , Özbay Pınar S. , Pamuk Uluç , Çağlar Kübra , Demir Elif M. , Yumak Mehmet , Yucesoy Can A. , Ozturk-Isik Esin
Published: August 2024

This study aims to investigate the effect of compressed sensing reconstruction on radiomics parameters of rat brain MRI at 7T. T2 weighted MRI of rat brain were randomly under-sampled with R=2.2 and reconstructed using compressed sensing. Brains were segmented after registration to a Wistar rat brain atlas. The radiomics of original and accelerated MRI data were compared in seven scans of rat brains using a Wilcoxon signed-rank test. Stable radiomics features were identified using intraclass correlation coefficients. The findings of this study indicated that not all radiomics features of rat brain were robust to compressed sensing acceleration.
Different multiparametric MRI-based radiomics models for differentiating stage IA endometrial cancer from benign endometrial lesions: A multicenter study
Authors: Bi Qiu , Wu Kunhua , Wu Yunzhu
Published: August 2024

In the study, age and irregular vaginal bleeding were the valid predictive parameters in clinical model. On the basis of several common machine learning algorithms, the diverse multiparametric MRI-based radiomics models were developed to differentiate stage IA EC from benign endometrial lesions, and LR algorithm model were selected as the optimal radiomics model with the highest AUC and accuracy. Compared with clinical model and radiologist, the optimal radiomics model and the compositive models combining clinical parameters with radiomics features, like the nomogram, stacking model, and ensemble model showed better diagnostic performance and achieved good clinical net benefits. The nomogram had a higher AUC than that of the optimal radiomics model, and revealed more stable discrimination efficiency and better generalization ability than stacking and ensemble modals.
MT-DICE for Simultaneous Quantification of Perfusion, Permeability, and Susceptibility
Authors: Chen Yang , Hu Zhehao , Xiao Jiayu , Shiroishi Mark , Yang Wensha , Li Debiao , Christodoulou Anthony , Fan Zhaoyang
Published: August 2024

We have recently developed an MR MultiTasking based Dynamic Imaging for Cerebrovascular Evaluation (MT-DICE) technique that provides DCE- and leakage-corrected DSC-MRI parameters simultaneously with one scan and a single-dose contrast injection. This work further expanded the technique by incorporating quantitative susceptibility mapping. The refined technique was validated in healthy volunteers and patients, demonstrating the good agreement with reference methods.
Resolution Dependency Study of Cerebral Blood Volume and Vessel Size Index
Authors: Gong Yelim , Lee DongKyu , Cho HyungJoon
Published: August 2024

To obtain cerebral vasculature related information, various kinds of cerebrovascular magnetic resonance imaging (MRI) technique are being applied. However, it turned out that cerebral blood volume (CBV) and vessel size index (VSI) values differ depending on their spatial resolutions. To find an adjustment solution for this phenomenon, the resolution dependency must be confirmed in advance. Therefore, this study aims to investigate the resolution dependency of CBV and VSI through whole brain and region of interest based analysis. The results show that micro CBV and VSI values are resolution-dependent, while total CBV did not show any distinct patterns.
MixRecon: A neural network mixing CNN and Transformer utilizes hybrid representations of image features for Accelerated MRI Reconstruction
Authors: Kang Hongjian , Zhang Liping , Chen Weitian
Published: August 2024

Accelerated reconstruction for magnetic resonance imaging (MRI) is a challenging ill-posed problem because of the excessive under-sampling operation in k-space. Existing CNN-based and Transformer-based solutions face difficulties obtaining powerful representation due to relatively unitary local or global feature modeling capability. In this study, we develop a dual-branch network that can simultaneously exploit the complementarity of the two-style features by leveraging the merits of CNN and Transformer, to generate high-quality reconstruction from zero-filled images in the spatial domain. Qualitative and quantitative results from the fastMRI dataset demonstrate that the proposed method can achieve improved performance compared with other benchmark methods.
On Training Model Bias of Deep Learning based Super-resolution Frameworks for Magnetic Resonance Imaging
Authors: Shrestha Mamata , Wang Nian , Nakarmi Ukash
Published: August 2024

Deep Learning based image super-resolution methods are biased towards training data modeling. Generalizability of DL based super-resolution frameworks can be improved by introducing variability and diversity in the training data.
Deep learning of 3D T2-weighted MRI provides support for arachnoid granulation hypertrophy in patients with Parkinson’s disease
Authors: Leguizamon Melanie , McKnight Colin , Eisma Jarrod , Song Alex , Elenberger Jason , Claassen Daniel , Donahue Manus , Hett Kilian
Published: August 2024

We apply novel deep learning algorithms using non-contrasted T2-weighted MRI to test hypotheses regarding arachnoid granulation (AG) hypertrophy in patients with Parkinson’s disease (PD). Using this method, we identify AGs protruding into the superior sinus lumen, which may serve as a site of CSF egress implicated in the neurofluid clearance system. Results suggest a significant increase in AG volume in the parietal and frontal lobes of PD participants compared to age-matched healthy controls, potentially indicative of reduced neurofluid clearance efficiency secondary to macromolecular aggregation along the CSF circuit.
Deep learning-based saturation band placement in spine localizer images
Authors: Saxena Ashish , Bhushan Chitresh , Ghose Soumya , Uday Patil , Padmanabhan Kameswari , NT Sanjay , Shanbhag Dattesh
Published: August 2024

Saturation band placement is important for obtaining good quality MRI images in presence of structures which can generate artifacts such as cardiac regions or large pulsating blood vessels. In anatomy such as spine, saturation-band placement can be time consuming since technologist has to ensure that it doesn’t overlap with vertebrae regions. In this study, we demonstrated an automated deep-learning method to accurately place the saturation band on 2D three-plane localizer images with no intervention from the technologist.
CEST effect of dimethyl sulfoxide (DMSO) at negative offset frequency
Authors: Su Haoyun , Huang Jianpan , Chan Kannie W.Y.
Published: August 2024

CEST MRI can detect mM range of endogenous and exogenous molecules, and bound small molecules such as glycogen and lactate via rNOE. Here we reported for the first time that DMSO and its structural analogs in aqueous solution had distinctive CEST peaks at the negative offsets of Z-spectrum. CEST effect of DMSO was dependent on saturation power and concentration, and less sensitive to tested temperature. Alcohols, acetone, acetonitrile, acetic acid and N,N-dimethylformamide also showed observable CEST peaks at the negative offsets. Interaction between DMSO and water molecule, such as hydrogen bonding, could contribute to the observed CEST effect.
Imaging treatment efficacy of repeated photodynamic therapy in glioblastoma using CEST MRI
Authors: Leung Vivian W.M. , Lai Joseph H.C. , Chen Zilin , Huang Jianpan , Park Se Weon , Liu Yang , Hu Charles , Chan Kannie W. Y.
Published: August 2024

Glioblastoma (GBM) is hard to treat and has poor prognosis. Photodynamic therapy (PDT) is a promising treatment for GBM. Here, we detect the treatment efficacies of different PDT schemes (repeated (re-) and single (s-) PDT) on a rodent model of GBM using CEST MRI to monitor the molecular changes associated with tumor physiology and necrosis. Significant decreases in APT and rNOE signals were detected in the rePDT group as well as decreased proliferative activities in histology when compared with sPDT. This indicates that both APT and rNOE can be a reliable approach to assess PDT treatment efficacy against GBM.
Paravascular Fluid Dynamics Reveal Arterial Stiffness Assessed using Dynamic Diffusion-Weighted Imaging (dDWI)
Authors: Wen Qiuting , Wright Adam , Tong Yunjie , Zhao Yi , Risacher Shannon , Saykin Andrew , Wu Yu-Chien , Riley Kalen , Limaye Kaustubh
Published: August 2024

We recently developped a novel technique, dynamic diffusion-weighted imaging (dDWI), for measuring paravascular cerebrospinal fluid (pCSF) dynamics. In this work, we evaluated the time shifts between the pulsation-driven pCSF waves (measured by dDWI) and finger pulse waves (measured by scanner’s built-in finger pulse oximeter) to calculate brain-finger pulse wave travel time. Our preliminary results of an aging cohort support that the dDWI-derived brain-finger TimeDelay can be a surrogate for arterial stiffness. This method can be used as an add-on analysis to the recently developed dDWI framework to offer information about the participant’s vascular conditions.
Associations between Extracellular Diffusivity Along Perivascular Space (eALPS) and Structural Abnormalities in Brain
Authors: Kim Sang-Young , Kim Eunju , Hwang Jinwoo , Kim Joo Hyun , Park Chae Jung
Published: August 2024

Non-invasive measure of glymphatic function or flow in vivo has gained a great attention from neuroscience research community. Diffusion tensor imaging (DTI) can provide a mean that measures the diffusivity along perivascular space (ALPS). However, conventional DTI captures diffusion indices from both tissue and free water compartments due to partial volume effects, which may raise a concern about validity of DTI-ALPS index for glymphatic function. In this work, we present a novel method that can extract extracellular diffusivity (i.e., eALPS) using free water eliminated DTI and investigate the relationship between eALPS and structural abnormalities in brain.
Desynchronized white matter function and structure in drug-naive first-episode major depressive disorder patients
Authors: Guo Qinger , Duan Jingfeng , Cai Shuyang , Zhang Jiaxi , Chen Tao , Yang Hong
Published: August 2024

Objective. To describe the abnormalities in WM function and structure in drug-naive first-episode MDD patients. Methods. 33 patients and 34 HCs were included. Different frequency bands of ALFF and FA were used to analyze the differences between the two groups. Results. Compared to HCs, patients showed decreased ALFF in PTR and SLF in slow-5 band, which were negatively correlated with the HAMD-17 anxiety/somatization factor items. No difference in FA between two groups. Conclusions. WM dysfunction relate to the pathophysiological mechanisms of MDD and predates structural damage. Compared to the typical and slow-4 bands, the slow-5 band is more sensitive for early detecting WM dysfunction.
White matter damage in end-stage kidney disease patients with cognitive impairment: a fixel-based analysis
Authors: Tsai Chih-Chien , Hou YI-Chou , Chen Yao-Liang , Wang Jiun-Jie
Published: August 2024

Patients with end-stage kidney disease are vulnerable to cognitive impairment or dementia. Previous studies indicated that end-stage kidney disease subjects manifest prominent white matter hyperintensities. We use fixel-based analysis to examine the tract-specific differences in fixel-based metrics between end-stage kidney disease patients and normal participants. The results demonstrate the pattern of white matter degeneration in end-stage kidney disease patients. Our findings suggest that end-stage kidney disease patients with cognitive impairment exhibit white matter abnormalities. In clinical, the fixel-based analysis may serve as a potential biomarker for monitoring white matter change caused by disease.
Investigating Alzheimer’s disease in women: is pregnancy a risk factor?
Authors: Pinto Joana , Sparks Sierra , Hayes Genevieve , Bulte Daniel
Published: August 2024

The influence of biological sex on clinical outcomes has been often neglected. Nevertheless, it is known that women have higher risk of dementia. Pregnancy might play an important role in this discrepancy, and studies have shown that this event is related to an increased risk of cerebrovascular impairment later in life. In this work we investigated the relation between the pregnancy related metrics and cognitive status and cerebral blood flow. Our results confirm that the number of pregnancies might be an important factor to consider when studying AD. Baseline CBF is not related to cognitive status or number of pregnancies.
Multi-shell DTI diffusion MRI Based Graph Theory Measures for Prediction of Cognitive Impairment in the Alzheimer’s Disease Connectome Project
Authors: Choi Timothy , Adluru Nagesh , Nair Veena , Chu Daniel , Garcia-Ramos Camille , Adluru Anusha , Li Shi-Jiang , Alexander Andrew , Bendlin Barbara , Prabhakaran Vivek
Published: August 2024

The prevalence of Alzheimer’s Dementia (AD) is on the rise, with an estimated economic burden to the US rivaling that of diabetes. Graph theory (GT) offers topological measures that can be used to detect connectivity changes due to aging and AD related processes. We aim to investigate the utility of GT measures based on multi-shell diffusion MRI (ms-dMRI) in discriminating aging individuals with cognitive impairment (CI) from healthy controls, and to find any intrinsic differences within the cognitively impaired subjects by clustering on the GT measures.
Relative Cerebral Blood Volume Differences Between Adult-Type Diffuse Glioma Subgroups According to WHO 2021: A Study of 146 Gliomas
Authors: Buz-Yalug Buse , Danyeli Ayca Ersen , Yakicier M. Cengiz , Pamir M. Necmettin , Ozduman Koray , Dincer Alp , Ozturk-Isik Esin
Published: August 2024

The main purpose of this study is to analyze the relative cerebral blood volume (rCBV) differences of adult diffuse glioma subgroups defined in the updated WHO 2021 brain tumor classification. The IDH wildtype group had statistically significantly higher rCBV values, and IDH mutational subgroups were classified with 82.5% accuracy (precision = 82.1%, recall = 82.9%), while the accuracies of glioblastoma and oligodendroglioma classification was 81.9%, glioblastoma and astrocytoma classification was 83.3%, and astrocytoma and oligodendroglioma classification was 77.5%.
The impact of naproxen on Cerebral Blood Flow in preclinical Alzheimer’s disease
Authors: Sanami Safa , Intzandt Brittany , Huck Julia , Group PREVENT-AD Research , Gauthier Claudine
Published: August 2024

Alzheimer’s Disease (AD) is the most common form of dementia and displays a long preclinical phase. The use of non-steroidal anti-inflammatory drugs (NSAIDs) in this phase has a protective effect and decreases the risk of developing AD cross-sectionally. However, the effects of NSAIDs therapy long-term on cerebral hemodynamics in this early phase is unclear. This is the first study to assess whether longitudinal use of NSAIDs (i.e., naproxen) has an impact on cerebral blood flow, and whether this is associated with a change in cognition and/or cerebrospinal fluid markers.
Intracranial Wall Permeability for Prediction of Aneurysm Growth Using Dynamic Contrast-Enhanced MRI
Authors: Xu Ziming , Dong Linggen , Zhang Longhui , Wang Yajie , Dou Jiaqi , Liu Peng , Lv Ming , Chen Huijun
Published: August 2024

Size of intracranial aneurysm (IA) is considered the most important clinical factor to determine the risk of IA rupture. Accurate prediction of aneurysm growth is crucial for preventive management but remains challenging. Herein, we studied the potential predictive roles of demography and imaging characteristics in a radiological follow-up study. And wall permeability calculated by DCE-MRI was firstly observed to accurately identify the IAs with a relatively high risk of aneurysm growth (AUC = 0.875). Our study demonstrated that higher wall permeability was associated with aneurysm growth and the regions with higher wall permeability co-localized with the direction of aneurysm growth.
Super-resolution reconstruction of time-resolved four-dimensional computed tomography (TR-4DCT) with multiple breaths based on TR-4DMRI
Authors: Liu Yilin , Ahamd Asala , Nie Xingyu , Li Guang
Published: August 2024

This study has demonstrated that the feasibility to reconstruct multiple-breath TR-4DCT via the super-resolution reconstruction framework through either CT4D→(MRBH→MRFB) or (CT4D←MRBH)→ MRFB deformable image registration. Using TR-4DCT, potential dosimetry consequences in radiotherapy of lung, liver, and pancreatic patients due to patient breathing irregularities can be readily assessed.
Tracking the moving stomach using MRI and neural ordinary differential equations
Authors: Wang Xiaokai , Cao Jiayue , Han Kuan , Choi Minkyu , She Yushi , Scheven Ulrich , Liu Zhongming
Published: August 2024

We describe a method, namely neural ordinary differential equations, to track the movement of the stomach based on dynamic and contrast-enhanced gastrointestinal MRI. This model uses a neural network to learn the continuous biomechanical process that drives the shape change of the stomach wall over the course of digestion. This method allows us to represent gastric motor events on a generic surface template of the stomach and to further reveal the pattern of gastric motility with higher specificity and resolution than are previously attainable in vivo. This method should be also applicable to other organs, such as the heart.
Accelerated Propeller FSE-DWI with Unrolled Deep Learning Reconstruction at 1.5T Clinical MRI
Authors: Yarach Uten , Suwannasak Atita , Sangpin Prapatsorn
Published: August 2024

Fast spin echo diffusion magnetic resonance imaging (FSE-DWI) is often referred to as a standard for MRI diagnosis of Cholesteatoma. However, the acquired data require multiple steps during image reconstruction which turn out high residual artifacts. In this work, we develop rapid reconstruction for propeller FSE-DWI to improve its signal-to-noise ratio (SNR) through unrolled deep learning (DL) framework. Results show that the proposed unrolled DL reconstruction enables increasing bout 2x SNR compared to SNR obtained by online reconstructed images. Moreover, its speed is about 200x faster than conventional locally low rank constraint reconstruction.