bluuebunny/crossref_metadata_2025 huggingface dataset:
Response linearity of functional Quantitative Susceptibility Mapping (fQSM) and effect of reduced z-coverage: a pilot study
Authors: Lancione Marta , Cencini Matteo , Costagli Mauro , Donatelli Graziella , Cecchi Paolo , Yang Baolian , Tosetti Michela , Biagi Laura
Published: November 2024

Motivation: fQSM quantitative and spatially-specific information on brain activity may be valuable in studying cortical substructures. However, fQSM response to varying stimulus intensity is unknown, and, as for QSM, reduced z-coverage may affect quantification. Goal(s): We aimed to assess fQSM linearity to stimulus intensity and its dependence on z-coverage. Approach: We employed visual stimuli with different contrasts and acquired whole-brain fQSM datasets that were truncated to simulate partial coverage. Results: We reported fQSM response linearity to different contrasts and, while extremely small coverage led to brain activity underestimation, whole-brain acquisitions were not necessary to obtain accurate results. Impact: Linearity and feasibility at reduced z-coverage, together with high spatial specificity, suggest that fQSM may provide added value to the functional study of cortical substructures.
Evaluation of Quantitative Susceptibility Mapping Methods for Cerebral Cavernous Malformation in Mice at 9.4T
Authors: Ho Timothy , Fisher Delaney , Sharifi Khadijeh , Vu Kevin , Hoch Matthew , Price Richard , Tvrdik Petr , Miller G. Wilson
Published: November 2024

Motivation: While GRE and SWI are the primary methods for identifying iron deposition in cerebral cavernous malformation (CCM), improved preclinical lesion characterization can be achieved by using Quantitative Susceptibility Mapping (QSM). Goal(s): Our goal was to introduce the use of QSM in a preclinical CCM model and evaluate the impact of the different QSM methods available. Approach: 8 healthy mice and 13 CCM mice were scanned using a multi-gradient echo and images were processed through each QSM method then compared using RMSE. Results: Each QSM method displayed large susceptibilities in areas suspected of CCM lesions. Impact: The addition of QSM for preclinical CCM may benefit longitudinal analysis. By establishing the use of QSM and further development in QSM calibration with ex vivo studies, QSM can be used for tracking CCM lesion progression noninvasively.
Patterns of Popular Artifacts in QSM and χ-separation (chi-separation)
Authors: Lee Hayeon , Min Kyeongseon , Ji Sooyeon , Youn Jonghyo , Kim Taechang , Kim Jiye , Sohn Beomseok , Kim Woo Jung , Park Chae Jung , Song Soohwa , Shin Dong Hoon , Chang Kyung Won , Shin Na-Young , Lee Phil Hyu , Choi Yangsean , Nam Yoonho , Kang Koung Mi , Burzynska Agnieszka , Lebel Catherine , Lee Jongho
Published: November 2024

Motivation: In QSM and χ-separation (chi-separation), artifacts from various sources may be introduced. The oversight of these artifacts could lead researchers to analyse inaccurate maps, resulting in potentially erroneous conclusions. Goal(s): The primary objective of this research is to investigate the characteristics, origins, and solutions related to artifacts encountered in QSM and χ-separation. Approach: We processed QSM and χ-separation in 364 subjects from Parkinson’s disease, Alzheimer’s disease, hypertension, and alcohol-exposed adolescents development studies, reporting various types of artifacts. They are categorized and explored for origins and potential solutions. Results: This study identified and provided solutions for 11 artifact types. Impact: While processing QSM and χ-separation in diverse subjects and vendors, various artifacts emerged. This study categorized these artifacts, investigated origins, mitigation strategies, and discernible effects on QSM and χ-separation results, aiding researchers and practitioners in artifact identification, correction, and exclusion.
Investigating Relationships Between Brain Magnetic Susceptibility, Transfusion Treatments, and Fine Motor Function in Sickle Cell Disease
Authors: Cherukara Matthew , Kawadler Jamie , Kirkham Fenella , Shmueli Karin
Published: November 2024

Motivation: Sickle cell disease (SCD) can lead to cognitive difficulties, but transfusion treatment presents a risk of iron overload which may lead to neurodegeneration. Better understanding of the impact of SCD and transfusions is needed. Goal(s): To use quantitative susceptibility mapping (QSM) to assess iron deposition in the brain in SCD with and without transfusions. Approach: Brain susceptibility was quantified in 28 SCD patients and 16 healthy controls using QSM and related to fine motor function by a general linear model. Results: Susceptibilities in deep brain structures were not correlated with transfusions, SCD status (except in substantia nigra), or motor function (except in pulvinar). Impact: Using an up-to-date QSM reconstruction pipeline reduced noise and artefacts and revealed correlations of susceptibility with age which were not found previously in these data, confirming the importance of correct coil combination for QSM studies.
Magnetic Resonance Imaging Findings Suggest that Cortical Thickness Mediates Glymphatic Effects on Cognitive Function in Alzheimer’s Disease
Authors: Guo Yihao , Liu Tao , Huang Weiyuan , Chen Huijuan , Zhu Jinxia , Chen Feng
Published: November 2024

Motivation: Glymphatic function, which eliminates soluble proteins from the brain, is positively associated with cognitive function for patients with Alzheimer’s disease (AD). Goal(s): To analyze whether the associations between glymphatic function and cognitive function were mediated by regional cortical thickness (CTh) for patients with AD. Approach: Mediator analysis was conducted to explore the ALPS index as a predictor, regional CThs as mediators, and cognitive test scores as outcomes. Results: Mediation analysis showed that regional CTh was a significant mediator between ALPS index and executive function. Impact: CTh is a key mediator between impaired glymphatic function and cognitive decline. Our findings provide insights regarding associations between decreased glymphatic function and cognitive decline in patients with AD.
Evaluation of glymphatic system and inflammation alteration in patients with brain metastases using DTI-ALPS and NLR
Authors: Yuxia Liang , Yu Shang , Xiang Liu , Ruoyan Qi , Maode Wang , MIng Zhang , Hui Liu , Chen Niu
Published: November 2024

Motivation: Malignant tumors always metastasize along the blood or meningeal infiltration. We hope to evaluate CSF and blood changes in brain metastases patients through a simple and effective method. Goal(s): To investigate glymphatic system and inflammation alteration in patients with brain metastases. Approach: We combined DTI-ALPS and NLR to analyze the differences between healthy controls and patients with brain metastases. Results: Compared with HCs, the mean ALPS index of patients with brain metastases was significantly decreased, and the NLR was significantly increased. Impact: ALPS-index and NLR can provide a new perspective for potential assessment of how brain metastasis affects the glymphatic system and inflammatory immune system, and may also support more relevant treatments for patients.
Investigating the characteristics of the region-of-interest for calculating the diffusion tensor imaging along perivascular spaces index
Authors: Ulloa Patricia , Rudolf Justus , Schmidt Aileen , Schramm Peter
Published: November 2024

Motivation: Several parameters affect diffusion tensor imaging along the perivascular spaces (DTI-ALPS) index calculation. However, the impact of ROI size, shape, and relative orientation to the lateral ventricle remains unclear, potentially hindering cross-study comparability. Goal(s): To investigate the influence of ROI characteristics in estimating the DTI-ALPS index. Approach: Differences in DTI-ALPS index and correlations among 8 ROI types (size, shape, and orientation) were investigated. Results: DTI-ALPS index calculation depends on ROI size, shape, and orientation. Single-voxel and parallel rectangular ROIs exhibit strong agreement; parallel-parallel and orthogonal-orthogonal ROIs show excellent correlation. However, larger, rectangular ROIs with orthogonal placement result in significant differences and poor correlation. Impact: Our analysis shows that ROI size, shape, and relative orientation to the lateral ventricle impact DTI-ALPS index calculation. Therefore, in addition to imaging parameters, ROI characteristics also need to be considered for comparison among studies.
Validation of diffusivity analysis along the perivascular space (ALPS) index as a biomarker for vascular cognitive impairment and dementia
Authors: Liu Xiaodan , Barisano Giuseppe , Maillard Pauline , Caprihan Arvind , Cen Steven , Shao Xingfeng , Jann Kay , Ringman John , Lu Hanzhang , Arfanakis Konstantinos , DeCarli Charles , Gold Brian T. , Satizabal Clandia L. , Habes Mohamad , Stables Lara , Singh Herpreet , Fischl Bruce , van der Kouwe Andre , Schwab Kristin , Helmer Karl G. , Greenberg Steven M. , Wang Danny JJ
Published: November 2024

Motivation: To test the validity of the ALPS index as a biomarker for VCIDGoal(s): To test our hypothesis that ALPS index is an independent biomarker for the cognitive decline in cSVD. Approach: Participants from MarkVCID consortium underwent baseline and follow-up MRI examinations and clinical evaluations of cognitive functionResults: We found the baseline ALPS index was correlated with the existing biomarkers of cSVD and VCID, and was independently associated with the baseline cognitive performanceImpact: Our study provides the clinical validation of the ALPS index as a sensitive and independent biomarker for the cognitive function of cSVD related VCID.
Feasibility Assessment of Measuring ADC of Meningeal Lymphatic Vessels using High-Resolution MUSE DWI and PROPELLER DWI
Authors: Liao Chun-Han , Cheng Yung-Yin , Peng Shin-Lei , Chang Hing-Chiu , Lin Shao Chieh , Juan Chun-Jung , Liu Chang-Hsien , Lee Ya- Hui , Lin Chao-Chun , Lin Chia-Wei , Liu Yi-Jui
Published: November 2024

Motivation: Is it possible to water diffusion be measured in meningeal lymphatic vessels (MLVs)?Goal(s): Diffusion-weighted MRI is employed to assess the circulatory condition of MLVs, eliminating the need for MRI with contrast agent administration, which typically requires monitoring for over 4 hours. Approach: Water diffusion measurements in MLVs were conducted using MUSE DWI and PROPELLER DWI, which offer low image distortion and high resolution. Results: Our results indicate that MLVs were clearly visible on high spatial resolution DWI and ADC maps, and the ADC values of MLVs are higher than those of GM and WM but lower than CSF. Impact: Since evaluating the circulatory condition of meningeal lymphatic vessels takes over 4 hours by contrast agent injection, our study investigates the feasibility of assessing the ADC of meningeal lymphatic vessels using high-resolution MUSE DWI and PROPELLER DWI.
Quantification of breathing-induced B0 field variations along the human spinal cord at 3T
Authors: Beghini Laura , David Gergely , Liechti Martina D. , Büeler Silvan , Jaffray Alexander , Vannesjo S. Johanna
Published: November 2024

Motivation: Breathing-induced B0 field variations cause artefacts in spinal cord MRI. Characterizing the variations is useful for optimizing correction strategies, but has not yet been done below the thoracic region. Goal(s): To quantify breathing-induced fields in the cervical, thoracic, and lumbar spinal cord, and to investigate their effect on image quality in multi-echo GRE. Approach: Field measurements were obtained from navigator projection lines in 2D slices, and were quantified by taking their standard deviation over time. Results: Breathing-induced field variations were detected in every subject, with a similar profile across vertebral levels. Levels with more intense field variations showed higher artifact load. Impact: Breathing-induced B0 fields impact image quality and exhibit a consistent pattern of variation along the spinal cord that is highly similar between subjects. Characterizing these variations lays the foundation for future optimized corrections to achieve consistently high image quality.
Highly segmented skipped-CAIPI 3D-EPI with a modified interleaved Flyback and partial Fourier acquisition for fast MR angiography
Authors: Blömer Simon , Stirnberg Rüdiger , Stöcker Tony
Published: November 2024

Motivation: As of yet, ghosting and signal dropouts limit the usability of EPI sequences for MRA-TOF compared to well-established methods such as GRE-TOF. Goal(s): Our goal was to mitigate flow artifacts in MRA-TOF images at short acquisition times whilst improving the efficiency of previous techniquesApproach: We introduced a novel Flyback sampling approach in a highly segmented skipped-CAIPI 3D-EPI sequence with phase partial Fourier to acquire in vivo data at a resolution of 0.6mm isotropic at 7T within about one minute. Results: The in vivo measurements show a significant reduction in ghosting and signal dropout and improved resolution of small vessels in TOF MIPs. Impact: Reduced acquisition times and flow artifacts of highly segmented skipped-CAIPI 3D-EPI with a modified, interleaved Flyback acquisition and partial Fourier may increase the applicability of EPI for fast MRA-TOF.
Imaging Near Metallic Implants: Initial 0.55T vs. 3T MRI Comparison in Hip Implant Patients
Authors: Keskin Kübra , Cui Sophia , Li Bochao , Gross Jordan , Buser Zorica , Lieberman Jay , Hargreaves Brian , Nayak Krishna
Published: November 2024

Motivation: Patients with orthopedic metallic implants often require diagnostic imaging to evaluate adjacent tissues. MRI performance, including artifact levels and SNR, varies with field strength. Goal(s): To compare 0.55T and 3T MRI for imaging patients with total hip arthroplasty (THA). Approach: Patients with THA were scanned with similar protocols at 0.55T and 3T, including multi-spectral imaging (MSI). We qualitatively compared the images from both scanners. Results: Metal artifact severity was reduced at 0.55T compared to 3T at the expense of SNR. Diagnostic imaging of patients with titanium hip implants at 0.55T is possible without MSI. Impact: We qualitatively compared 0.55T and 3T image quality in patients with hip replacements. Our findings indicate that 0.55T MRI offers substantially reduced metal artifacts and advanced multi-spectral techniques may not be required in many cases.
Self-supervised Contrastive Learning for Automatic Image Quality Assessment in Whole-body MRI: Preliminary results in UK Biobank
Authors: Ecker Veronika , Früh Marcel , Yang Bin , Gatidis Sergios , Küstner Thomas
Published: November 2024

Motivation: MRI is vital for many medical decisions, yet susceptible to motion artifacts. Impairment by motion artifacts can reduce the reliability of diagnoses and a motion‐free reacquisition can become time-/cost‐intensive. Moreover, in large-scale cohorts, manual inspection is impractical. An automated quality assessment is desirable, but collection of motion-free references is challenging or even impractical. Goal(s): We aim for automatic image quality assessment without extensive labeled training data. Approach: We present a self-supervised quality classification framework based on SimCLR operating as zero-shot learning. Results: The framework achieves promising results for binary quality classification, while showcasing its potential for future work as continuous quality score. Impact: By automating MRI quality assessment, our approach helps in preventing artifact propagation into downstream tasks without additional efforts for manual inspection or data labeling.
Relationship between Head Motion and Scattering: in-Silico Evaluation of Linearity
Authors: Simmons Hugh , Mailhe Boris , Hess Aaron
Published: November 2024

Motivation: To investigate the relationship between head motion and scattering for potential future work on motion correction, using radio frequency sensors to detect changes in head pose. Goal(s): Establish if scattering changes are linearly related to head translations or rotations. Approach: Simulations were run using the Sim4Life EM FDTD software with a human model at different positions relative to a coil model. Results: Translations in the x and y directions varied co-linearly with scattering. However, rotations and z-translation display both linear and non-linear relationships. Impact: These results allow for a greater understanding of the relationship between head motion and scattering, and demonstrates the potential for scattering to be used as a rapid, contact-free head pose tracker.
Hybrid Motion Correction: Latency Compensation In The Presence Of Respiratory Motion
Authors: Laustsen Malte , Gaass Thomas , Slipsager Jakob , Frost Robert , Ganz Melanie , van der Kouwe André , Glimberg Stefan
Published: November 2024

Motivation: Prospective motion correction (PMC) techniques face challenges due to inherent latency and filter-induced delays, particularly impactful in cases of periodic motion, like breathing. Goal(s): This study examines how periodic motion affects PMC with increased latency and employs retrospective techniques to compensate for latency-induced discrepancies. Approach: Brain MRI scans were conducted on a volunteer performing exaggerated breathing using a PMC-enabled sequence. Retrospective motion correction was used to reverse latency-induced errors and compensate for residual motion. Results: The hybrid approach combining PMC and RMC yielded superior results when compared to no correction and PMC-only, emphasizing the importance of addressing latency in motion correction for MRI. Impact: Breathing motion can lead to suboptimal results in prospective motion correction. Implementing this technique broadens PMC's applicability, aiding its integration into clinical practice.
Comparison of Fat Navigators and Optical Camera Based Retrospective Motion Correction
Authors: Zhao Bingbing , Zhou Yichen , Diao Xuanhang , Zhu Lixuan , Zhang Han , Zong Xiaopeng
Published: November 2024

Motivation: A comparison between efficacies of navigators and optical camera in retrospective motion correction (MC) on brain MR images remains largely unknown. Goal(s): Our goal was to compare two motion tracking techniques (fat navigators [FatNav] and markerless optical camera [MoCAP]) and their performance in MC. Approach: Twenty-one healthy subjects were imaged by T2-weighted turbo-spin-echo sequence with their head movements monitored simultaneously by both techniques. Performance was evaluated by image sharpness calculated at lateral ventricle/white matter boundary. Results: Compared to MoCAP, FatNav had lower motion scores and less fluctuations at small motion. Images after FatNav-based MC showed greater sharpness than MoCAP. Impact: The better performance of FatNav-based MC despite low temporal resolution suggest that FatNav can be integrated with MoCAP to achieve robust image quality in the presence of both abrupt and slow head motions.
Flexible Receiver Coil Using Direct-3D-Write Technology at 0.55T
Authors: Muñoz Felix , Islam Mohammad , Stark Helmut , Le Ted , Nayak Krishna , Khan Yasser
Published: November 2024

Motivation: MRI receiver coils are often rigid thus cannot conform to every anatomy. This motivates to create flexible, robust, and easy to manufacture coils. Goal(s): To create scalable and low-cost MRI coils using direct-3D-writing. The coils should conform to different anatomies and be robust to bending and stretching. Approach: We utilize a fast direct-3D-write method (~8 minutes print time per coil) that uses an easy to modify coil model, and compare performance against a rigid copper coil at 0.55 Tesla. Results: The flexible printed coil provided 1.8 times higher SNR compared to the reference copper coil due to better form-fitting. Impact: MRI receiver coils, printed with the direct-3D-write method, can be made flexible to conform to imaging anatomy, while offering scalability and lower cost. This simplifies manufacturing and improves SNR due to better form-fitting.
Clinical Imaging of Patients with Spinal Hardware at 0.55T: Diagnostic Feasibility and Metallic Artifact Comparison to 1.5/3T
Authors: Kelsey Lauren , Seiberlich Nicole , Bapuraj Jayapalli , Gulani Vikas , Mishra Shruti
Published: November 2024

Motivation: MR image quality concerns due to metallic implants may be addressed by preferentially scanning on 0.55T units. Goal(s): To assess image quality, metallic artifacts, and diagnostic agreement secondary to spinal hardware at 0.55T compared to higher-field imaging. Approach: Two blinded neuroradiologists independently reviewed 20 0.55T studies and 10 paired high-field studies. Diagnostic efficacy of 0.55T scans was assessed via pick-list, and image quality and metal artifact reduction were assigned scaled ratings. Results: 0.55T produced studies with high diagnostic efficacy (16/20 studies had complete or near-complete agreement) and equivalent or improved image quality compared to higher-field images. Impact: Commercial 0.55T MRI systems may improve the appearance of artifacts caused by spinal hardware compared to higher fields, and can be used in routine clinical practice without compromising image quality or diagnostic efficacy.
Comb EMI: a hardware-free, training-free approach to EMI correction
Authors: Sun Heng , Sun Chenhao , Ha Yonghyun , Samardzija Anja , Gross Ryan , Galiana Gigi , Constable R.
Published: November 2024

Motivation: Point-of-care MRI systems need electromagnetic interference (EMI) cancellation with limited passive shielding to improve cost and portability. Existing methods require external hardware or training, which increases costs and design complexity. Goal(s): This novel solution targeting narrowband EMI is hardware-free, training-free, introduces no white-noise and can be used in conjunction with other methods. Approach: Exploiting the sparsity, L1-regularized compressed sensing is used to extract EMI from a comb-shaped sampling window that consists of noise-dominated regions in acquisition. Results: With proof-of-concept implementation, robust EMI cancellation is demonstrated on both simulated and experimental data, with comparable performance to collector-based method despite the lack of extra hardware. Impact: Point-of-care MRI systems can further push SNR and save scan time by removing narrowband EMI without the cost of additional hardware or training data, enabling new design possibilities for fast, portable, and economically accessible MRI.
Four-channel receiver coil array for focused ultrasound spine imaging
Authors: Lee Hsin-Ju , O'Reilly Meaghan , Jones Ryan , Lin Fa-Hsuan
Published: November 2024

Motivation: MRI with the focused ultrasound treatment on the spine has low image quality, presumably due to a tailored receiver coil array. Goal(s): A receiver coil array for 3T MRI is developed to image the spine of a large animal during focused ultrasound (FUS) treatment using a flat, large-aperture (25 cm diameter) phased array transducer. Approach: A 4-channel receiver coil array was built with a housing curved to conform to the back of the specimen. Results: Structural images with T1- and T2-weighted contrast confirmed an SNR gain of approximately 50% using this coil array compared with images acquired using a body coil. Impact: The FUS-compatible spine MRI receiver coil array will enhance visualization of BSCB openings. As a clinical application, this coil array will also alleviate intraprocedural imaging challenges.
MR Thermometry with a Deep-Learning Reconstruction
Authors: Huang Sherry , Wang Xinzeng , Lebel Marc , Abad Nastaren , Hushek Steve , Yeo Desmond , Holmes James
Published: November 2024

Motivation: Improved MR thermometry is needed for thermal-based therapies. Goal(s): Improve precision while maintaining accuracy by denoising proton resonance frequency shift (PRFS)-based thermometry images using a deep learning-based reconstruction (DLR). Approach: 2D fast spoiled gradient-echo (FSPGR) images were acquired on a variety of phantoms with and without heating. Complex images were reconstructed with and without DLR to calculate temperature change maps. The mean and standard deviation of ROIs were analyzed to demonstrate any changes in accuracy and precision. Results: DLR improves precision and maintains accuracy in PRFS temperature change maps in phantoms. Impact: The improvements indicate an opportunity to increase spatial and/or temporal resolution in MRI thermometry. It may be possible to improve MRI-based heating optimization during clinical thermal therapies.
Mild hyperthermia induced by MRgHIFU as an adjuvant to radiation therapy in bone metastases: preliminary results of a phase I study
Authors: Lorton Orane , M’Rad Yacine , Guillemin Pauline , Gau Max , Tsoutsou Pelagia , Zilli Thomas , Poletti Pierre-Alexandre , Salomir Rares , Boudabbous Sana
Published: November 2024

Motivation: Mild hyperthermia (HT) induced by magnetic resonance-guided focused ultrasound (MRgHIFU) before radiation therapy (RT) could act as adjuvant in pain relief for bone metastasis. Goal(s): This study aims to evaluate the feasibility and safety of MRgHIFU procedure in one patient with a posterior right acetabulumApproach: The target temperature elevation was 6°C. The targeting and temperature monitoring in near real-time were performed by MRI. Results: The temperature elevation lasting 30-minutes was 6.01°C on average in bone metastasis. The MR-guidance allowed a safe and successful procedure without adverse events. The 25-minutes between HT end point and RT demonstrated the technical feasibility of the procedure. Impact: This study is a first step to demonstrate MRgHIFU hyperthermia adjuvant to palliative radiotherapy of bone metastases. The non-invasive, safe and accurate use of focused ultrasound to sensitize tumors opens the way to more efficient application of the radiation dose.
Multi-Modality Imaging and Analysis of Mouse Cortex after Focused Ultrasound-Induced Blood-Brain Barrier Opening.
Authors: Murphy Devin , Samoy-Alvarado Alex , Carlson Rhea , Howison Christine , Matsunaga Terry , Utzinger Urs , Trouard Theodore , Hutchinson Elizabeth
Published: November 2024

Motivation: The gold-standard for confirmation of blood-brain barrier (BBB) disruption after FUS is T1-weighted MRI with contrast enhancement. Conventional MRI-based metrics cannot differentiate between BBB leakage at the microvascular level, and thus there is a need for validation with higher spatial and temporal resolution modalitiesGoal(s): Use 2-photon microscopy to investigate solute extravasation from the microvasculature into the parenchyma and paravascular space. Approach: This project is an in-vivo validation of BBB opening after FUS using 2-photon microscopy and MRI. Results: Results suggest BBB opening occurs in capillaries, and that dye extravasation can be measured within minutes of sonication. Impact: Sub-micron imaging of the microvasculature after BBB opening will provide insight into which vessels are opened after FUS and improve pharmacokinetic understanding of the paravascular space around arterioles and venules.
Multi-Class 3D Transformer-Based Segmentation of the Liver, Liver Vessels, and Interventional Needle on Intra-Procedural 3D MRI
Authors: Zhou Wenqi , Li Xinzhou , Kaufman Justin , Lu David , Wu Holden
Published: November 2024

Motivation: Localization of liver, liver vessels, and interventional needle on 3D magnetic resonance imaging (MRI) provides essential information for MR-guided interventions. Goal(s): To develop a multi-class network for segmenting the three classes on intra-procedural 3D MRI. Approach: 3D Swin UNEt Transformer (UNETR) with pre-trained model weights was trained with data augmentation. Needle localization was performed based on the predicted needle segmentation. Results: In six-fold cross validation of 42 3D images, the multi-class model achieved median Dice scores of 0.87, 0.64, 0.76 for liver, liver vessels and needle. The needle tip localization showed improvements compared to a single-class 3D Swin UNETR model. Impact: We trained the 3D Swin UNETR for 3D liver, liver vessel, and interventional needle segmentation on intra-procedural 3D MRI and showed that the needle localization performance can be improved using multi-class model compared to single-class model for needle localization.
Whole Brain Coverage Multi-Target Framework for Benchmarking RF Arrays Tailored for Thermal Magnetic Resonance of Glioblastoma Multiforme
Authors: Rahimi Faezeh , Millward Jason , Schuhmann Rolf , Niendorf Thoralf
Published: November 2024

Motivation: Thermal Magnetic Resonance (ThermalMR) adds a thermal intervention dimension to MRI by focusing E-fields in the target region (TR). Today’s assessment of RF applicators uses TRs covering a few specific but arbitrary locations in the brain. This approach does not represent the full clinical picture. Goal(s): This work introduces a multi-target evaluation (MTE) framework and expands RF applicator evaluation to whole brain coverage. Approach: MTE using EMF simulations for a helmet and for an annular RF applicator. Results: Our MTE approach provides a technical foundation for the development and objective evaluation of RF applicators tailored for ThermalMR. Impact: MTE provides a technical foundation for objective RF applicator evaluation using whole brain coverage instead of a few specific but arbitrary target locations. Our framework presents a springboard for RF applicator design and for ThermalMR-based therapy of glioblastoma multiforme.
Analyzing the Impact of Transcranial Direct Current Stimulation on the Human Primary Visual Cortex through fMRI-based Brain Entropy
Authors: Qian Rui , Shuai Yifan , Liao Chengjiaao , Zhou Yangling , Zhang Shaomin , Wu Dan , Wang Minmin , Zhao Zhiyong
Published: November 2024

Motivation: Specific impact of Transcranial Direct Current Stimulation (tDCS) on the human primary visual cortex (V1) remains unclear. Goal(s): We used fMRI-based brain entropy (BEN) method to investigate the effects of short- and long-term tDCS on brain activity, and dynamic changes of BEN during tDCS. Approach: The resting-state fMRl data were collected before, during and after stimulation from 10 healthy subjects. Results: We observed reduced BEN values after both short- and long-term tDCS in frontoparietal and occipital areas. During tDCS, the brain preferred to stay in a state with lower BEN values in the default mode network compared to other brain regions. Impact: Short- and long-term tDCS on V1 both have a positive effect on improving cognitive functions in healthy and psychiatric disorder population. We also further validated the utility of BEN as an effective method for assessing tDCS effects.
Artificial Sparsity Enhanced Deep Learning BUDA Imaging Enables Rapid and Distortion-corrected High-Resolution 3D-EPI and QSM
Authors: Chen Zhifeng , Jin Jin , Mcintyre Richard , O'Brien Kieran , Stäb Daniel , Law Meng , Chen Zhaolin
Published: November 2024

Motivation: MR susceptibility mapping serves as a highly valuable tool in various neuroscientific and clinical applications. Goal(s): This innovative approach is designed to facilitate fast and robust high-resolution whole-brain imaging and quantitative susceptibility mapping (QSM). Approach: In this study, our primary objective was to create a distortion-free 3D-EPI with blip-up/down acquisition (BUDA), incorporating controlled aliasing in parallel imaging (CAIPI) sampling, and applying artificial sparsity enhanced deep learning image reconstruction. Results: Our developed technique holds the potential to produce distortion-free high-resolution whole-brain quantitative susceptibility mapping in just 12s at 3T and 9s at 7T, achieving an impressive resolution of 1 mm isotropic. Impact: The proposed 3D-BUDA, incorporating a 2D CAIPIRINHA acquisition sequence with artificial sparsity-enhanced self-supervised deep learning reconstruction, demonstrated its ability to deliver rapid, distortion-free, high-resolution, whole-brain T2*-weighted imaging and QSM.
DeepSNMs for highly accelerated multi-contrast volumetric brain imaging
Authors: Zhao Jiaying , Jia Sen , Cheng Jing , Jiao Chunlin , Cui Zhuoxu , Li Ye , Liu Xin , Zheng Hairong , Liang Dong
Published: November 2024

Motivation: The conventional multi-contrast 3D reconstruction process is time-consuming and lacks sufficient acceleration factors. Goal(s): To achieve highly accelerated multi-contrast brain imaging while enhancing reconstruction efficiency, the learnable CNN network is utilized. Approach: Deep learning regularized SNMs (Deep SNMs) is developed by unrolling parallel imaging reconstruction using spatial nulling maps (SNMs) with CNN regularization. The network is iteratively expanded by gradient descent blocks and 2D convolution blocks. Results: Compared to L1 regularized SNMs, the learnable CNN regularization simplifies reconstruction complexity and attains higher image quality. DeepSNMs achieves multi-contrast volumetric brain imaging reconstruction under caipirinha 9x and 12x acceleration. Impact: This work successfully accomplishes multi-contrast volumetric brain imaging with 9-fold and 12-fold caipirinha acceleration. By addressing the time-consuming challenge of reconstructing multi-contrast 3D images, this work effectively utilizes and integrates information from multiple contrasts concurrently.
Variational Network Meets Conjugate Gradient: Inline Reconstruction and Strain Analysis of Accelerated Cardiac Cine MRI
Authors: Vornehm Marc , Wetzl Jens , Fürnrohr Florian , Giese Daniel , Ahmad Rizwan , Knoll Florian
Published: November 2024

Motivation: Accelerated cardiac cine MRI is prone to motion artifacts and underestimation of imaging biomarkers. Furthermore, many approaches lack prospective evaluation. Goal(s): Improve data-driven reconstruction of cardiac cine MRI and enable inline reconstruction with improved estimation of strain parameters. Approach: Training a neural network based on a Variational Network combined with intermediate conjugate gradient optimizations and evaluation on retrospectively undersampled data. Inline integration into scanner software using the FIRE framework and prospective evaluation in terms of image quality and cardiac strain parameters. Results: The proposed network outperformed established compressed sensing approaches both retrospectively and prospectively, and in both image quality and cardiac strain estimation. Impact: Our research enables inline reconstruction of highly accelerated (up to real-time) cardiac cine MRI with high motion fidelity and improved strain estimation compared to well-established compressed sensing approaches.
Navigator-gated 2D radial MR fingerprinting of the kidney at 3T.
Authors: Calarnou Pauline , Ogier Augustin , Ledoux Jean-Baptiste , Aslam Ibtisam , Vallée Jean-Paul , Yerly Jérôme , Van Heeswijk Ruud
Published: November 2024

Motivation: A free-breathing renal joint T1-T2 MR fingerprinting technique with respiratory navigators would allow kidney function to be mapped non-invasively in patients that cannot hold their breath. Goal(s): To assess the effect of rejected respiratory navigators on the relaxation times and their precision. Approach: Joint kidney T1-T2 maps with four different navigator acceptance window widths (NAWW, from ±4mm to ±32mm) were acquired in 8 healthy volunteers and compared to clinical routine maps. Results: Map accuracy and precision were high and did not change as a function of NAWW, suggesting that the NAWW can be chosen as a balance between navigator inefficiency and through-plane motion. Impact: This work demonstrates the feasibility of a free-breathing 2D joint T1-T2 renal MR fingerprinting in healthy volunteers. The navigator allows a free breathing acquisition with limited through-plane motion.
Combining ASL and MRE to Investigate the Impact of Perfusion on Renal Stiffness in Patients with CKD: A Preliminary Study
Authors: Chen Yueyao , Luo Peiyin , Qi Ruirui , Chen Qiuyi , Li Junfeng , Liang Qiumei , Liu Wenxi , Qin Haodong , kuehn bernd , Meng Fanqi , Lyu Hanqing , Pan Jingtong , Qu Feifei , Wu Yanglei
Published: November 2024

Motivation: The impact of renal perfusion on stiffness values is yet to be conclusively validated, which has hindered the diagnostic application of magnetic resonance elastography (MRE) in patients with chronic kidney disease (CKD). Goal(s): To explore the characteristics of renal perfusion and stiffness values in patients with CKD and their correlation. Approach: Renal MRE and arterial spin labeling (ASL) were used to measure renal stiffness and blood flow. The study employed t-test, receiver-operating characteristic curves, and Spearman correlation for data analysis. Results: The two techniques were effective in diagnosing CKD, simultaneously confirming the influence of perfusion factors on stiffness. Impact: This preliminary human study further supported the correlation between renal stiffness and perfusion, supporting the enhanced diagnostic efficacy of combining MRE and ASL for CKD, thus facilitating staging.
Effect of Bronchodilator Treatment on Pulmonary Artery Pulse Wave Velocity in COPD measured with PREFUL MRI
Authors: Wernz Marius , Voskrebenzev Andreas , Müller Robin , Zubke Maximilian , Klimeš Filip , Hohlfeld Jens , Wacker Frank , Vogel-Claussen Jens
Published: November 2024

Motivation: Vascular stiffness and secondary pulmonary hypertension in COPD are common. Noninvasive measurement of pulse wave velocity as a marker of arterial stiffness by PREFUL MRI is feasible. The effect of bronchodilators on PWV is unclear. Goal(s): To determine the effect of bronchodilators on pulmonary artery stiffness as measured by PWV derived using PREFUL MRI. Approach: PREFUL MRI in 52 patients before and after placebo-controlled bronchodilator treatment. Results: In patients with elevated PWV, a significant decrease in PWV was measured after treatment. In the placebo control period and in the patients with normal baseline PWV, no significant changes were observed. Impact: Pulmonary artery stiffness can be measured by PREFUL MRI-based pulse wave velocity (PWV) calculation. PREFUL MRI is a promising tool to monitor PWV changes after bronchodilator treatment.
Oxygen-enhanced Ultrashort Echo Time MRI in Diagnosis of Benign and Malignant Solid Pulmonary Nodules: a preliminary study
Authors: Wang Xianqi , Liu Jinsha , Wang Xingang , Li Jing , Xiang Shaoxin , Yang Yuxin , Yang Taotao , Zeng Meng , Chen Wei
Published: November 2024

Motivation: People pay more and more attention to the high incidence and mortality of lung cancer. Goal(s): To develop a non-invasive, radiation-free imaging scheme to distinguish between benign and malignant solid pulmonary nodules and to improve the management of patients with pulmonary nodules. Approach: Two three-dimensional ultrashort echo time series scans of pulmonary nodules were performed on 3.0T MRI under the condition of 21% and 100% oxygen, respectively, and the percent signal enhancement was used as the evaluation index of benign and malignant nodules. Results: The increase of the percent signal enhancement in benign pulmonary nodules was higher than that in malignant pulmonary nodules. Impact: This imaging tool will reduce or eliminate the radiation damage caused by computed tomography, reduce clinicians' over-dependence on high resolution computed tomography, and bring new gospel for personalized and accurate diagnosis and treatment of patients.
Pulmonary Perfusion via Magnetic Resonance Imaging is Associated with hospitalization for COVID-19
Authors: Afyouni Shadi , Lancaster Andy , Zandieh Ghazal , Noda Chikara , Kato Yoko , Liu Chia-Ying , Kassai Yoshimori , Lima Joao , Venkatesh Bharath Ambale
Published: November 2024

Motivation: COVID-19's persistent respiratory effects are well-documented, but the long-term pulmonary consequences, particularly after severe illness, remain inadequately understood. Goal(s): To identify enduring perfusion deficits in the lungs of individuals previously hospitalized with COVID-19, using dynamic contrast-enhanced (DCE) MRI. Approach: The study recruited adults post-COVID-19 for a comprehensive pulmonary assessment. Dynamic contrast enhanced MRI was used to quantify lung perfusion and relating them to COVID-related hospitalization. Results: The study found a significant correlation between MRI perfusion parameters and previous hospitalization for COVID-19. It indicated that patients with a history of hospitalization due to COVID-19 might experience persistent alterations in lung perfusion. Impact: Our research, through dynamic contrast-enhanced MRI, reveals persisting lung perfusion deficits in post-hospitalized COVID-19 patients, notably related to severity of initial disease. This aids in understanding post-COVID pulmonary sequelae, guiding future patient management and research on long-term COVID-19 impact.
Variability in measurements of abdominal blood flow using non-invasive phase-contrast-mapping MRI
Authors: Haddock Bryan , Østergaard Frederikke , Rasmussen Rasmus , Langberg Ludvig , Alstrup Lotte , Larsson Tanne , Asmar Ali , Larsson Henrik , Andersen Ulrik , Gasberg Lærke , Vestergaard Mark
Published: November 2024

Motivation: Measuring the reproducibility of 2D PC-MRI measures of intestinal blood flow is important for its clinical application. Goal(s): The aim is to examine the precision of 2D PC-MR measures of resting intestinal blood flow and postprandial blood flow changes. Approach: Ten healthy men were scanned on eight different days collecting at least three repeated 2D PC-MRI measures each day. Participants were also given an oral glucose tolerance test. Results: A CoV of 6%-9% was obtained for consecutive flow measures and 13%-15% for between day measurements. Flow increased 75% in the arteria mesenterica superior and 60% in the vena portae after glucose consumption. Impact: The low variability of repeated flow measures in the arteria mesenterica superior and vena portae compared to the high change in flow after glucose consumption makes 2D PC-MRI measures of flow changes in these vessels a feasible diagnostic test.
Consistency of hemodynamics information measured by 4D Flow MRI and 2D phase contrast MRI in patients with mild to moderate carotid artery stenosis
Authors: BIN WANG , liangjie Lin , Jie LU
Published: November 2024

Motivation: The blood flow of carotid artory can be assessed by the standard 2D PC MRI, as well as the advanced 4D Flow MRI. Goal(s): The aim of this study is to test the potential of 4D flow for accuracy of quantification of carotid flow parameters compared to the reference standards 2D PC MRI in patients. Approach: 4D Flow MRI and 2D PC MRI were performed in patients with carotid artery stenosis. Quantitative hemodynamics of carotid arteries were measured in 2D PC and 4D Flow MRI. Results: 4D Flow MRI and 2D PC MRI had a good consistency in the evaluation of carotid hemodynamics. Impact: This study found that 4D Flow MRI and 2D PC MRI had a good consistency in the evaluation of carotid hemodynamics in patients with mild to moderate carotid artery stenosis.
Ultra-low-field Neck Time-of-flight MRA at 0.05 Tesla: A Preliminary Study
Authors: Su Shi , Ding Ye , Hu Jiahao , Zhang Junhao , Lau Vick , Zhao Yujiao , Wu Ed
Published: November 2024

Motivation: The recent resurgence of ultra-low-field MRI (i.e., below 0.1 T) is showing great promise for future clinical applications due to its low cost, portability, and accessibility, potentially advancing neck MRA for evaluating and diagnosing carotid diseases in point-of-care scenarios and low/mid-income countries. Goal(s): To explore the neck MRA using TOF technique at 0.05 Tesla. Approach: Flow-compensated 2D GRE sequences with and without flow saturation for multi-slice neck scans. Results: Carotid arteries/bifurcations and jugular veins can be visualized with strong vessel-to-background contrast. We envision that usable and quality neck MRA can be potentially achieved at ULF with further sequence and/or post-processing optimization. Impact: Ultra-low-field (ULF) neck MRA can potentially advance the evaluation of carotid stenosis and occlusion, as well as the diagnosis of stroke and aneurysms, in point-of-care scenarios and low/mid-income countries.
Evaluation of blood flow changes in iliac vein compression: a hemodynamic model based on magnetic resonance multimodal imaging and CFD simulation
Authors: Wang Shu , Liu Zhe , Ding Ningning , Zhou Li , Zhu Guangyu , Ai Kai , Zhu Yi , Yang Jian
Published: November 2024

Motivation: Hemodynamic changes are important for evaluating Iliac venous compression syndrome. CFD simulation can obtain individualized and quantitative hemodynamic information that traditional imaging methods cannot obtain. Goal(s): Qbtain hemodynamic parameters through the establishment of patient individualized vascular model and CFD simulation. By observing hemodynamic parameters, the changes in blood flow caused by iliac venous compression can be more accurately evaluated. Approach: The 3D model is constructed based on the MRA images. After CFD simulation, changes of flow dynamics parameters observed due to the influence of iliac venous compression. Results: The CFD simulation shows that iliac venous compression can cause significant changes in hemodynamicsImpact: Hemodynamic changes are the pathological basis of iliac venous compression. Accurate diagnosis of blood flow changes is helpful to guide the surgical treatment of iliac venous compression and provide powerful help for clinical decision-making.
Joint Optimization Sampling and Reconstruction of Multi-Contrast MRI under Specific Scan Sequence Combination
Authors: Geng Jianing , Zhou Zijian , Qi Haikun , Hu Peng
Published: November 2024

Motivation: The current multi-contrast MRI sampling and reconstruction methods cannot efficiently collect complementary information to achieve better reconstruction performance. Goal(s): A method was designed to generate corresponding sampling masks for each contrast image in a multi-sequence clinical scanning scenario, collect the optimal complementary information for better application in multi-contrast joint reconstruction. Approach: We jointly optimized the sampling and reconstruction of multi-contrast images, and designed learnable acceleration ratio and decoder feature fusion for images with different contrasts. Results: The PSNR and SSIM metrics of reconstructed images have significantly improved, and different sampling masks can be generated for different contrasts and sampling order. Impact: The method of jointly optimizing the sampling and reconstruction of multi-contrast images in a single scan may provide a powerful tool for accelerating and optimizing the MRI scanning process and improving the reconstructed quality of the multi-contrast images.
Hankel-based data preparation method for radial MRI artifact removal from undersampled zero-filled images
Authors: Ghaffarzadeh Sina , Makhsousi Faeze , Feizifar Babak , Ghodrati Vahid , Moghaddam Abbas Nasiraei
Published: November 2024

Motivation: Hankel-based reconstruction distorts the image's center less than its periphery. This prompts us to examine Hankel-based reconstruction for neural network training data preparation. Goal(s): To train the model-agnostic neural network on Hankel-based reconstruction data to improve image center reconstruction. Approach: A neural network trained on Hankel-based reconstruction data was compared to an equivalent network trained on NUFFT-based reconstruction data. Results: In the context of radial dynamic imaging, where the ROI can be placed in the center of the image, our approach achieved better results than when using NUFFT-based data preparation for reconstruction of undersampled radial data. Impact: This study might influence dynamic radial-MRI reconstruction. Our data preparation for training and testing the network improved cardiac-MRI qualitative outcomes, especially in the heart region. The radial-MRI society may find the proposed solution appealing when paired with DL-based approaches.