bluuebunny/crossref_metadata_2025 huggingface dataset:
An Advanced (k,T)-acquisition scheme to largely improve sensitivity and resolution for dynamic deuterium MRSI application in human brain at 7T
Authors: Wiesner Hannes , Li Yudu , Li Xin , Zhu Xiao-Hong , Liang Zhi-Pei , Chen Wei
Published: November 2024

Motivation: Further improving the spatial resolution and sensitivity of human brain deuterium MRSI (DMRSI). Goal(s): To develop an advanced (k,T)-acquisition scheme and processing pipeline to improve the SNR and resolution of dynamic DMRSI at 7T. Approach: We designed and implemented the new DMRSI pulse sequence on an FDA-approved 7T clinical scanner equipped with a 4-channel 2H-1H dual-frequency transreceiver head array coil; evaluated and compared the new (k,T)-CSI sequence and the FSW-CSI sequence performing high-resolution dynamic DMRSI. Results: The new DMRSI method significantly improves the SNR and spatial resolution and achieved better contrast between human GM, WM and CSF. Impact: We developed an advanced DMRSI method for high-resolution and high-fidelity whole-brain DMRSI in humans at 7T. It enhances our ability to study neuroenergetics and metabolic reprograming associated with brain tumors and other neurological disorders, and provides clinical value for diagnosis.
Fast and Motion-Robust Non-Contrast MR Angiography using Centric ky–kz Trajectory.
Authors: Malis Vadim , Bae Won , Vucevic Diana , Kassai Yoshimori , Hsiao Albert , Nakamura Katsumi , Miyazaki Mitsue
Published: November 2024

Motivation: The purpose of this study is to develop a fast, motion-robust fresh blood imaging (FBI) technique using a centric ky–kz k-space trajectory (cFBI) and an exponential refocusing flip angle (eFA) scheme. Goal(s): Investigate scan time reduction and image quality of cFBI and compare it with the standard FBI technique. Approach: Advancement of the cFBI sequences with eFA and optimized cardiac trigger delays on a 3-T MR imager, aiming to reduce the scan time and maintaining the image quality. Results: cFBI outperforms standard FBI in scan time reduction with good image quality with less motion-related artifacts and Nyquist N/2 artifacts. Impact: A two-fold reduction in scan time is achieved with the non-contrast FBI technique, while still maintaining image quality and reducing motion and N/2 artifacts.
Deep Learning based Phase Correction with Noise and Artifacts Removal for MERGE
Authors: Shen Daming , Wang Xinzeng , Lan Patricia , Sun Wei
Published: November 2024

Motivation: Multiple Echo Recombined Gradient Echo (MERGE) images are inherently complex-valued, and motion, field inhomogeneities, etc. could cause echo-to-echo background phase variations. Filter-based phase correction often results in signal cancellation. Goal(s): To remove echo-to-echo phase variations for complex echo combination and improve the in-plane resolution and SNR of complex combined imageApproach: We used a deep-learning-based phase correction to improve complex echo combination and apply AIR Recon DL to further improve the in-plane resolution and SNRResults: Deep learning based phase correction minimized signal cancellation and enabled robust complex echo combination With AIR Recon DL, MERGE images showed improved resolution and SNR. Impact: With improved image quality, it could improve the visualization, segmentation and measurement of tissue of interest, improving diagnosis, treatment response monitoring, etc.
Rapid ∆B0 Field Mapping for Real-Time Shimming of Human Brain
Authors: Jayadev Nutandev Bikkamane , Chang Yulin , van der Kouwe Andre , Stockmann Jason , Frost Robert , Arango Nicolas , Andronesi Ovidiu
Published: November 2024

Motivation: High-quality MRI demands accurate ∆B0 field mapping. Traditional field mapping methods cannot address motion-induced susceptibility changes during acquisition. A rapid navigator can achieve real-time motion correction with accurate shim and frequency updates. Goal(s): Develop a rapid navigator to achieve accurate field maps for real time motion correction applications. Approach: We developed GRAPPA accelerated dual-echo EPI-vNavs of rapid ∆B0 field mapping. We compared field mapping and shim current accuracy of vNavs at different resolutions and accelerations to 3D-GRE in scanner-based 2SH and multi-coil shimming. Results: The field maps generated with accelerated vNavs closely matched 3D-GRE field maps and accurately determined shim currents. Impact: Accelerated dual-echo EPI vNavs provide rapid, accurate field mapping, reducing feedback delays. This research provides valuable insights into impact of acceleration and resolution in vNav-based field mapping, to benefit various MRI applications in mitigating susceptibility artifacts arising from motion-induced changes.
MR Imaging of tumor vascular normalization: DCE and IVIM
Authors: Yu Jing , Cheng Yong , Wu Peng , Gao Bo
Published: November 2024

Motivation: The prognosis for patients with advanced nasopharyngeal carcinoma is often poor. Although anti-angiogenic therapy can enhance the effectiveness of chemo-radiotherapy, drug resistance remains a challenging issue. Accurately monitoring the time window for vascular normalization is crucial. Goal(s): The objective of this study was to assess the value of DCE-MRI and IVIM-MRI in dynamically monitoring tumor vascular normalization. Approach: By applying different antiangiogenic therapies to preclinical models, this study evaluated the effectiveness of DCE and IVIM in monitoring tumor vascular normalization (TVN). Results: Preliminary results suggest that IVIM-MRI can potentially replace DCE-MRI in monitoring tumor vascular normalization. Impact: This study holds profound implications for the clinical application of anti-angiogenesis therapy. It provides valuable insights into the effectiveness of combination therapies and offers a deeper understanding of vascular normalization indicators. These findings could potentially improve treatment strategies.
An fMRI-based investigation for financial decision-making from Neurofinance perspective
Authors: Srivastava Mrinalini , Kumaran S Senthil , Srivastava Achal Kumar , Sharma Gagan Deep , Singh Himanshu
Published: November 2024

Motivation: Neurofinance has shown great opportunity for researchers in the field of finance to understand the financial decision-making process at the neurological level. Goal(s): To investigate the decision-making process through fMRI technique using IOWA Gambling task to understand the significance of education (financial management education in this study) for acquiring financial literacy skills for better financial decision making. Approach: fMRI technique is used to identify the brain activation patterns for acquisition of financial literacy skills and further exploring the role of training on learning, memory. Results: We identified areas with association of memory and learning during financial decision-making via IGT task. Impact: Neuroscience provides the foundation for comprehending affective influences on financial decisions. In recent years, neurological, behavioural and cognitive approaches have given economics and finance an impetus and has led to the emergence of the disciplines in Neurofinance and Neuroeconomics.
T2*-weighted echo-planar imaging of the human brainstem and spinal cord at 7 Tesla with region-wise geometry, timing, and shim parameters
Authors: Finsterbusch Jürgen , Chu Ying , Büchel Christian , Eippert Falk
Published: November 2024

Motivation: Combined fMRI acquisitions of human brainstem and cervical spinal cord helps to investigate their interaction, e.g., during pain processing. Goal(s): To test whether combined T2*-weighted EPI of both regions is feasible at 7 Tesla. Approach: EPI pulse sequence supporting region-wise geometry (FOV, slice thickness, voxel size), timing (echo spacing, echo time), and shim parameters (linear terms and frequency), and flip angles together with a region-wise shim algorithm extended to consider static third-order shim terms. Results: A reasonable image quality could be obtained in both regions, but strategies to reduce ghosting artifacts in the spinal cord need to be investigated. Impact: Being able to cover human brainstem and cervical spinal cord regions in a single EPI acquisition at 7 Tesla can help to investigate the interaction of both regions with improved spatial resolution.
On z-shimming: settings maximizing the signal amplitude may not be derivable from the linear field component and may depend on the echo time
Authors: Finsterbusch Jürgen
Published: November 2024

Motivation: Z-shimming ameliorates through-slice dephasing in T2*-weighted functional neuroimaging but, surprisingly, a linear fit to the field in slice direction may not provide z-shim settings yielding the maximum signal. Goal(s): To demonstrate that optimum z-shim settings should be obtained from a reference acquisition stepping through a range of z-shims at the desired echo time. Approach: Numerical simulations of the MR signal were performed for different through-slice field distributions, echo times, and z-shims. Results: Z-shims derived from the linear fit minimize the dephasing but this is not equivalent to maximizing the signal. Furthermore, optimum z-shim settings may depend on the echo time. Impact: The results could help to optimize z-shim settings in T2*-weighted acquisitions used for BOLD-based functional neuroimaging by using a reference acquisition stepping through a range of z-shims at the desired echo time rather than a fit to the field distribution.
Improved physiology-induced temporal stability achieved with variable-flip-angle FLEET multi-shot Echo Planar Time-resolved Imaging (EPTI)
Authors: Hu Zhangxuan , Berman Avery , Dong Zijing , Grissom William , Reese Timothy , Wang Fuyixue , Wald Lawrence , Polimeni Jonathan
Published: November 2024

Motivation: EPTI is a new highly-efficient imaging approach that addresses limitations of EPI by providing high-resolution distortion- and blurring-free imaging for fMRI. However, shot-to-shot phase-variations induced by physiological processes in conventional multi-shot EPTI can introduce instabilities into the reconstructed time-series data. Goal(s): Improving physiology-induced temporal stability of multi-shot EPTI. Approach: Combing multi-shot EPTI with the VFA-FLEET method, which minimizes shot-to-shot phase-variations by reordering the multi-shot acquisitions while maximizing the signal level by using a variable-flip-angle train and recursive RF pulse design. Results: In vivo fMRI data acquired at 7T demonstrate that the physiological instabilities of multi-shot EPTI can be substantially reduced with proposed method. Impact: Here we test whether temporal instabilities in conventional multi-shot EPTI time-series caused by physiological variability can be reduced by combining EPTI with the variable-flip-angle FLEET method. This combination can improve the usability and robustness of EPTI for high-resolution fMRI studies.
Proposal of self-resonance spin-lock sequence: adaptable contrast fMRI sequences
Authors: Ueda Hiroyuki , Taniguchi YO , Ito Yosuke
Published: November 2024

Motivation: To propose the novel spin-lock sequence employing phase modulation (self-resonance spin-lock: SR-SL). There is no report on self-resonance during the spin-lock pulse, and we would like to share this idea through this report. Goal(s): To demonstrate the feasibility of SR-SL and characterize its pros and cons. Approach: Mathematical analysis of the Bloch equation, numerical simulation, and phantom experiment. Results: All the results of three approaches agreed. We confirmed the phase modulation could control the operating point of MR image contrast, which provides us with desired contrast change depending on the target magnetic field. Impact: We proposed the novel spin-lock sequence named self-resonance spin-lock (SRSL), which can control the operating point of MR image contrast and provides desired contrasts. SR-SL has potential to improve sensitivity to magnetic fields and save saturation absorption rate.
Changes in resting state functional connectivity within and between brain networks reveal effects of an injury to motor cortex in monkey brain
Authors: Sengupta Anirban , Wang Feng , Mishra Arabinda , Wang Pai Feng , Reed Jamie , Chen Li Min , Gore John
Published: November 2024

Motivation: To evaluate whether changes in resting state functional connectivity within and between brain functional networks reveal the effects of an injury to motor cortex in squirrel monkey brain. Goal(s): The goal was to quantify the connectivity changes within and between functionally relevant regions of a squirrel monkey brain post a motor cortex lesion. Approach: Resting state BOLD signals were acquired and analyzed by correlating functional MRI time courses from ICA detected networks using Pearson’s correlation.Results: Differential changes in connectivity measures were observed both within and between functional networks post the lesion which indicates the usefulness of studying both the measures in conjunction. Impact: The study demonstrates the utility of within-network connectivity measures in conjunction with the traditional approach of computing between-network connectivity to investigate the effects of a motor cortex injury. This has translational value in early diagnosis and treatment planning in patients.
Validation of Resting State Functional Connectivity of S2 in Squirrel Monkey Brain: Comparisons with Optogenetic and Tactile fMRI
Authors: Yang Zhangyan , Yang Pai-Feng , Wang Feng , Reed Jamie , Chen Li Min , Gore John
Published: November 2024

Motivation: To validate the derivation of functional networks from resting state and confirm the contribution of specific neuron types to BOLD responses. Goal(s): Our aim is to compare resting state BOLD-derived functional networks with those from neuron-type selective optogenetic and natural tactile stimulationin the non-human primate brain. Approach: We compared the BOLD signals in the brains of squirrel monkeys under three conditions: in response to blue light optogenetic stimulation, vibrotactile stimulation of fingers, and in a resting state. Results: It shows the neural specificity of the optogenetic fMRI approach and its potential to enhance the understanding of brain circuits and connectivity within S2. Impact: This study's validation of functional networks from resting-state BOLD acquisitions and the confirmation of optogenetic fMRI's neural selectivity helps with the understanding brain function. These results encourage further investigations for deeper insights into neurological conditions.
9.4T MR based rs-fMRI of anesthetized mice after passive hyperthermia
Authors: Ruan Yang , Liu Kai , Li Bo , Lei Hongxia , Xing Yao , Sun Gang
Published: November 2024

Motivation: The effects of passive hyperthermia on brain function in resting-state mice are unknown. Goal(s): To expiore the rs-fMRI in hyperthermia treated and normal mice brain. Approach: The ICA network and ROI-ROI FC in passive hyperthermia mice brain were compared with normal control. Results: The ICA networks changed and the overall ROI-ROI FC of the passive hyperthermia mice decreased. Impact: After prolonged exposure to high temperature has a greater impact on the overall perception and cognitive level of mice, which might help understand the relationship between neuronal activities and physiological thermal sensation and regulation as well as behavioral changes.
Comparing responses to visual and auditory stimuli in anesthetized and minimally restrained awake mice using quiet zero echo time MB-SWIFT fMRI
Authors: Stenroos Petteri , Dvořáková Lenka , Salo Raimo , Paasonen Ekaterina , Michaeli Shalom , Mangia Silvia , Zehnder Tamara , Mueggler Thomas , Künnecke Basil , Paasonen Jaakko , Gröhn Olli
Published: November 2024

Motivation: Anesthesia is a major confounding factor for pre-clinical fMRI and thus awake fMRI protocols with minimal body restraints are needed. Goal(s): Our goal was to develop a novel motion-tolerant fMRI approach for awake mice and to compare sensory responsiveness between awake and anesthetized mice. Approach: Following a 14-day habituation protocol, mice were imaged using zero-echo-time MB-SWIFT fMRI with visual and auditory stimulation schemes in awake state and under ketamine-xylazine anesthesia. Results: In awake mice, the activation of all key nodes was detected after both sensory stimuli. However, anesthesia suppressed particularly the auditory responses and affected the fMRI response shapes. Impact: Awake animal imaging has gained much popularity in recent preclinical studies. Together with quiet and motion-tolerant MB-SWIFT imaging our approach has potential for more complex behavioral fMRI designs that improve our understanding of neuroscience and support translational drug discovery.
Multidimensional analysis of longitudinal mechanical stimulus-induced fMRI in Mice of both sexes
Authors: Chen Hui-Fen , Pradier Bruno , Bhatti Hammad , Chao Hsin-Yi , Nagelmann Nina , Sandbrink Martin , Augustin Mirjam , Segelcke Daniel , Pogatzki-Zahn Esther , Faber Cornelius
Published: November 2024

Motivation: Acute postsurgical pain remains difficult to treat and may result in complications including chronic pain and increased use of opioids if insufficiently controlled. Goal(s): A better understanding of the mechanisms inducing and maintaining these pain states is critical in both sexes. Approach: Longitudinal task fMRI was performed with two different mechanical stimulations in male and female mice following acute incision pain (INC) compared to sham-treated animals. Results: Our mixed-method analysis approach identifies INC-regulated brain regions and highlights divergent mechanical pain processing in mice of both sexes. Impact: Our mixed-method analysis approach integrating the general linear model analysis combined with principal component analysis and analysis of functional connectivity provides deep insights into CNS plasticity during incision-induced pain and provides detailed information on relevant brain regions and interaction patterns.
The relationship between preoperative PI-RADS version 2.1 and Gleason score change after radical prostatectomy
Authors: Zhang Jiahui , Xu Lili , Jin Zhengyu , Sun Hao
Published: November 2024

Motivation: If reliable preoperative risk factors to predict Gleason score (GS) upgrading after radical prostatectomy (RP) are identified, such could be helpful to reduce the risk of misclassification of PCa patients. Goal(s): To investigate the relationship between Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1) and GS change after RP. Approach: Multivariate analyses were performed to analyse the factors influencing GS change after RP. Results: Multivariate regression analysis showed positive biopsy cores of ≥ 4, biopsy Gleason score of <7 and PI-RADS v2.1 score of 4–5 were independent predictors of GS upgrading after RP (all P < 0.05). Impact: Combining the number of positive biopsy cores, biopsy Gleason score and PI-RADS v2.1 score could significantly improve the diagnostic efficiency for Gleason score upgrading after radical prostatectomy.
Development of preoperative nomograms to predict the risk of overall and multifocal positive surgical margin after radical prostatectomy
Authors: Peng Qianyu , Xu Lili , Zhang Gumuyang , Zhang Jiahui , Zhang Xiaoxiao , Bai Xin , Chen Li , Guo Erjia , Jin Zhengyu , Sun Hao
Published: November 2024

Motivation: Preoperative prediction of the risk of positive surgical margin (PSM) is important for optimal treatment decision-making in patients with prostate cancer. Goal(s): To develop preoperative nomograms using risk factors based on clinicopathological and MRI for predicting the risk of PSM after radical prostatectomy. Approach: Preoperative clinicopathological factors and MRI-based features were recorded for analysis. The presence or absence of PSM (oPSM) at pathology and the multifocality of PSM (mPSM) were evaluated. Results: The nomogram for oPSM reached an AUC of 0.717 in development and 0.716 in internal verification. The AUC of the nomogram for mPSM was 0.790 in both development and internal verification. Impact: The proposed nomograms showed good performance and were feasible in predicting oPSM and mPSM. The evaluation of risk factors and the application of nomograms preoperatively might facilitate individualized management of prostate cancer.
PSMA PET/CT and mpMRI discrepancies in prostate cancer detection with whole-mount histopathology gold standard
Authors: Sonni Ida , Doddipalli Sahith , Deol Madhvi , Ban David , Kim Hye Ok , Grogan Tristan , Ahuja Preeti , Barroso Nashla , Zong Yang , Soin Priti , Weiner Adam , Sisk Anthony , Calais Jeremie , Hsu William , Czernin Johannes , Reiter Robert , Raman Steven
Published: November 2024

Motivation: In prostate cancer (PCa), multiparametric MRI (mpMRI) and PSMA-PET aid pre-surgical assessment. This study evaluates parameters linked to the agreement/disagreement of PSMA-PET and mpMRI with histopathology. Goal(s): To evaluate the concordance between PSMA-PET, mpMRI, and histopathology in PCa lesion identification. Approach: Patients with PSMA-PET, mpMRI, and histopathology data were analyzed. Imaging lesions were contoured independently. Sensitivity and agreement were assessed. Logistic regression models examined factors affecting concordance. Results: Among 114 patients, PSMA-PET and mpMRI identified 170 and 138 lesions, respectively. Tumor aggressiveness and size impacted agreement. Higher SUVmax on PSMA-PET and higher ISUP grade and size on pathology were associated with concordance. Impact: This work improves prostate cancer diagnosis by identifying key factors influencing the agreement between PSMA-PET, mpMRI, and histopathology, offering valuable insights for more precise pre-surgical assessments.
Testing diagnostic quality after speeding up prostate MRI by reducing the number of echo-trains in T2-weighted TSE.
Authors: Mir Nida , Lohuizen Quintin , Fütterer Jurgen , Yakar Derya , Kwee Thomas , Wolterink Jelmer , Simonis Frank
Published: November 2024

Motivation: Increasing prostate cancer cases are leading to a rising demand for prostate MRI, which is a time-consuming protocol. Speeding up of this protocol will help relieve the rising pressure on the healthcare system. Goal(s): To speed up the T2W TSE by undersampling the data, while maintaining the diagnostic outcome. Approach: Echo-trains with center-lines farthest from the k-space center are removed, to undersample the data semi-incoherently , followed by a Compressed Sense reconstruction. Results: Up to 17% time gain can be achieved while the diagnostic outcome remains unaffected. Impact: The scan time of T2W TSE can be reduced by selectively removing echo-trains based on their center-line distance to the k-space center, without affecting the diagnostic outcome, defined by the PI-RADS score and qualitative parameter ratings.
MRI-based Radiomics Analysis for Clinically Significant Prostate Cancer Diagnosis using a Standardized Prostate Segmentation Model
Authors: Naim Sohaib , Zhao Kai , Zheng Haoxin , Yan Ran , Raman Steven , Sung Kyunghyun
Published: November 2024

Motivation: Despite the growing use of multiparametric MRI (mpMRI), there remains an unmet need for additional quantitative methods to improve prostate cancer (PCa) localization by prostate anatomic zones. Goal(s): To extract radiomics features that determine differences in detection rates (DRs) and positive predictive values (PPV) for clinically significant PCa (csPCa). Approach: We extracted shape- and first-order based features from 543 csPCa lesions across 468 male subjects and used the Mann-Whitney U test to assess differences in key features. Results: csPCa lesions located at anterior and TZ prostate regions had significantly larger shape-based features and significantly smaller first-order features than posterior and PZ regions, respectively. Impact: For patients with csPCa, significant radiomics features extracted from mpMRI lesions in the anterior and transition zone prostate regions show significantly larger shape-based features and significantly smaller first-order features than csPCa lesions in the posterior and peripheral zone regions, respectively.
Correlation Between Morphological Measurements of Intra- and Extracranial Vessel Wall and Whole-Body Fat Distribution Characteristics
Authors: Zhang Hong , Li XuanLe , Xu Yue , Cheng Chuanli , Wu Yingtong , Qin Jiangjun , Li Ye , Liang Dong , Liu Xin , Zheng Hairong , Zhang Na
Published: November 2024

Motivation: Obesity is associated with cardiovascular diseases. However, its effect on cerebrovascular disease remains unclear. Goal(s): To investigate the correlation between morphological measurements of intra- and extracranial arterial vessel walls and whole-body fat distribution characteristics. Approach: A total of 98 volunteers underwent three-dimensional high-resolution MR vessel wall imaging and whole-body MR proton density fat fraction (PDFF) imaging on a 3.0T MRI scanner. Results: The results indicate that the vessel wall thickness of both the extracranial carotid artery and vertebral artery is positively correlated with visceral adipose tissue and the liver-PDFF. Impact: The assessment of vascular health in individuals with central obesity necessitates a comprehensive evaluation of both extracranial carotid arteries and vertebral arteries. This paradigm shift may have far-reaching implications for the prevention and treatment of cerebrovascular diseases associated with obesity.
Improving background suppression of intracranial spiral time-of-flight MRA with phase-sensitive water-fat separation
Authors: Wang Dinghui , Chao Tzu Cheng , Pipe James , Leiner Tim
Published: November 2024

Motivation: Efficient fat suppression can improve flow visualization in time-of-flight (TOF) MRA. We hypothesize that the phase difference of water and fat may be used for efficient fat suppression for out-of-phase (OP) TOF MRA. Goal(s): To demonstrate the feasibility of fat suppression for spiral TOF with sliding-slice localized quadratic (ssLQ) encoding using the phase-sensitive approach. Approach: After the general reconstruction of ssLQ OP TOF, the global slowly varying phase was estimated and removed. Water and fat voxels were then identified according to their phase. Results: Background suppression was substantially improved with the proposed method, resulting in enhanced visualization of small vessels. Impact: The proposed phase-sensitive approach requires no changes of pulse sequence and negligible computational cost. It might be implemented with a wide range of OP TOF MRA for fat suppression.
Comparison between 3T non-selective pulse non-enhanced whole-heart bTFE coronary MR angiography and 3T mDixon water-fat separation GRE method
Authors: Yuan Yong , Lu Guangming , Jin Dongsheng , Chen Weibo , Wang Baijun , Chen Tong , Hu Qiuju , Zhu Jiajia , Zhao Yane
Published: November 2024

Motivation: To improve the image quality of the non-enhanced whole heart bTFE CMRA sequence at 3T. Goal(s): To compare the performance of a newly improved bTFE CMRA sequence with the mDixon water-fat separation GRE method at 3T for CMRA. Approach: Success rate, acquisition time, image quality, and diagnostic performance were compared. Results: This study demonstrated that the performance of the 3D bTFE CMRA sequence at 3T was brilliant, with a high success rate, appropriate acquisition time, excellent image quality, and good diagnostic performance. Impact: The non-enhanced bTFE CMRA sequence at 3T may be recommended for more extensive clinical applications.
Quantitative Flow Visualization in a Patient-Specific Compliant Type B Aortic Dissection Phantom Using 0.55T MRI
Authors: Bilgi Coskun , Moghaddam Abbas , Geng Haojie , Kumar Prakash , Magee Gregory , Nayak Krishna , Pahlevan Niema
Published: November 2024

Motivation: PC-MRI allows for both in-vivo and in-vitro evaluation of complex flow patterns. The accuracy and consistency of these measurements needs to be re-evaluated at new low- and mid-field strengths such as 0.55T. Goal(s): To evaluate flow and velocity patterns using 0.55T PC-MRI to assess the scanner’s suitability for complex flow quantification. Approach: Using an in-vitro human circulatory setup with a patient-specific type-B aortic dissection phantom to measure complex velocity fields. Results: Excellent agreement between MRI-obtained and measured flowrates were observed. Complex rotational flow patterns were captured. Results are consistent within slices and experimental conditions, demonstrating the efficacy of 0.55T MRI for flow evaluation. Impact: This study establishes the viability of 0.55T MRI for phase contrast imaging for three-dimensional velocity field measurements. The findings validate the consistency of flow quantification, and open new avenues for further opportunities on complex flow visualization.
Non-invasive estimation of relative pressure in the murine aortic arch using virtual work-energy (vWERP)
Authors: Winter Patrick , Andelovic Kristina , Kampf Thomas , Herold Volker , Zernecke Alma , Jakob Peter , Bauer Wolfgang , Marlevi David , Schnell Susanne
Published: November 2024

Motivation: MRI-based relative pressure is a promising imaging biomarker. A new technique, vWERP, improves pressure estimations compared to more simplified approaches. Validated in clinical settings, it's unexplored in mouse models. Goal(s): To apply the vWERP algorithm to MRI-microscopy for pressure measurements in wild-type and atherosclerotic mouse models. Approach: 4D flow MRI was performed in wild-type and ApoE-/- mice. Post-processing involved segmenting the aorta, defining analysis planes, and calculating pressure drops using the vWERP algorithm for analysis. Results: Using vWERP with 4D flow MRI shows promise for studying vascular disease hemodynamics. Preliminary findings suggest pressure as a robust parameter to examine changes in CVD progression. Impact: Application of vWERP to MRI-microscopy in mice reveals high potential for assessing cardiovascular disease progression, particularly in studying pressure changes. This new diagnostic tool benefits vascular health studies in preclinical settings and may be used to study atherosclerotic plaque development.
MRI findings of aneurysmal inside and walls associated with sac shrinkage after endovascular aortic repair
Authors: Nakagomi Teppei , Mine Takahiko , Abe Masashi , Sekine Tetsuro , Yasui Daisuke , Kobayashi Rika , Happoh Seigoh , Ikeda Shinpei , Kawase Yasuhiro , Fujii Masahiro , Hayashi Hiromitsu , Kumita Shin-ichiro
Published: November 2024

Motivation: To survey radiographical parameters to predict outcomes after EVAR. Goal(s): To reveal new MRI findings associated with aneurysmal shrinkage. Approach: Various MRI findings were extracted from fifty patients and the relationship between each finding and aneurysmal volume change was analyzed. Results: Lack of endoleak, endoleak with clear boundary shapes, homogenous signal pattern or uncomplex heterogenous signal pattern of intra-aneurysmal thrombus, and aneurysmal wall enhancement and thickening were noted as the factors for sac shrinkage. Impact: Some specific MRI findings as lack of endoleak, clear endoleak boundary, homogenous or uncomplex heterogenous thrombus, and aneurysmal wall enhancement thickening were noted as the factors for sac shrinkage.
An Open-source, Flexible, Plug-and-Play Inline CMR Image Segmentation Platform
Authors: Assana Salah , Morales Manuel , Castiglione Jonah , Johnson Scott , Pierce Patrick , Rodriguez Jennifer , Chow Kelvin , Wallace Tess , Kitslaar Pieter , Manning Warren , Nezafat Reza
Published: November 2024

Motivation: Cardiac magnetic resonance (CMR) image segmentation remains a time-consuming task. Deep learning (DL) segmentation models have advanced considerably in recent years, but they lack flexibility for manual adjustments. Goal(s): We sought to develop an open-source, flexible plug-and-play inline CMR image segmentation platform. Approach: We implemented in-house algorithms in a clinical scanner as separate Python modules, allowing new and existing DL models to be integrated into clinical workflow. Results: We assessed the feasibility of the automated plug-and-play platform for inline cine segmentation in 308 patients referred for clinical CMR. Impact: This platform facilitates the rapid development and evaluation of any segmentation algorithm in a transparent and reproducible fashion. An open-source, flexible, plug-and-play inline CMR segmentation platform will enable rapid testing and evaluation of new segmentation and analysis algorithms.
Monitoring relative diameter change of the carotid artery using non-contrast-enhanced 4D dynamic angiography: preliminary results
Authors: Quesada Isabel Montón , Ogier Augustin , Ferincz Robin , Ledoux Jean-Baptiste , Bustin Aurélien , Michel Patrik , Yerly Jérôme , Stuber Matthias , Roy Christopher , van Heeswijk Ruud
Published: November 2024

Motivation: The carotid artery anatomy is routinely studied with MRI, whilst its relative diameter change is evaluated using ultrasound. An MRI technique to measure the carotid diameter change throughout the cardiac cycle could therefore be complementary to the existing toolset. Goal(s): To combine carotid MR angiography and diameter change quantification in one scan without contrast agent injection. Approach: A 4D (3D+time) free-running sequence was extended with slab-selective RF pulses to increase the inflow blood-to-muscle contrast. Carotid diameter changes and contrast ratios were quantified. Results: The contrast ratio significantly improved with the use of slab-selective pulses and the carotid relative diameter change was precisely measured. Impact: 4D free-running MR angiography with slab-selective RF pulses allows for the dynamic visualization of the carotid lumen and the quantification of the relative carotid diameter change throughout the cardiac cycle without contrast agent injection.
RAMI: Radiomics Predictive Model of Myocardial Infarction and Microvascular Obstruction
Authors: Santinha Joao , Correia Teresa
Published: November 2024

Motivation: Late gadolinium Enhancement (LGE) is the method of choice for assessing myocardial infarction (MI) and viability, essential to guide revascularization decisions. LGE also shows no-reflow regions that occur when blood flow remains inadequate post-revascularization. Existing automatic segmentation methods identify regions of LGE uptake but ignore no-reflow regions. Goal(s): Our goal is to provide a robust and automated solution for the detection of MI and no-reflow. Approach: We propose two LGE-based radiomics models, RAMI and RAMI-NOR, to improve MI diagnosis and detect no-reflow, respectively. Results: RAMI distinguishes normal and pathological cases accurately. RAMI-NOR shows potential in assessing MI with no-reflow but needs further refinement. Impact: The proposed RAMI and RAMI-NOR methods extract radiomics features from LGE images to automatically detect infarcted and microvascular obstruction areas, essential for the diagnosis and treatment management of patients suffering from myocardial infarction.
The combination of carotid plaques characteristics and white matter lesions burden may predict ischemic stroke severity in symptomatic patients
Authors: Cui Zhimeng , Zhang Jun
Published: November 2024

Motivation: Acute care decisions, such as the initiation of anticoagulant therapy, are affected by infarction degree. Goal(s): To assess the severity of ischemic stroke and prognosis in patients with symptomatic carotid artery stenosis, this study combined cerebral WMLs burden derived from FLAIR and carotid plaque characteristics based on HRVW-MRI to construct a noninvasive model. Approach: Logistic regression analysis and LASSO regression analysis were utilized to develop predictive nomogram model. Results: The AUC of predictive model was 0.92 in the training and 0.88 in the validation cohort, and showed good clinical utility. The hybrid model-derived score was an independent predictor of mRS score. Impact: The high discriminative ability indicates the potential of this model for classifying patients with nervous functional defect according to NIHSS score.The hybrid model-derived score is related to judge the neurological function recovery.
PCASL with a clinically practical ischemia-hyperemia protocol for use in critical limb threatening ischemia
Authors: von Stempel Conrad , Bray Timothy , Kirkham Alex , Tsui Janice , Sokolska Magdalena
Published: November 2024

Motivation: Lower-limb vascular imaging used in advanced peripheral arterial disease PAD) is limited to luminography with no functional tissue perfusion data. Goal(s): MRI ASL perfusion quantification is a contrast agent free technique that promises to be a novel imaging biomarker for tissue viability. However, current implementations have several limitations, including low signal-to-noise and the need for a substantial period of hyperemia to induce measurable perfusion in the muscle. Approach: We aimed to develop an abbreviated, clinically-practical ischemia-hyperemia paradigm to measure perfusion, and to evaluate this in volunteers. Results: A 2-minute period of ischemia produced hyperemia a doubling of baseline perfusion, sustained for 30 seconds. Impact: Quantitative perfusion imaging with pseudocontinuous arterial spin labelling can be achieved in the lower limb with an ischemia-hyperemia paradigm with 2 minutes of ischemia. This clinically applicable technique can be used in the assessment of peripheral arterial disease.
CMR-based estimation of mean pulmonary arterial pressure and pulmonary vascular resistance in CTD-PAH
Authors: Ma Kefan , Zhu Yidan , Liu Wangyan , Zhu Xiaomei , Wang Qiang , Sun Xiaoxuan , Zhu Yinsu , Xu Yi
Published: November 2024

Motivation: This research explores the potential of cardiac magnetic resonance (CMR) as a noninvasive tool for evaluating pulmonary arterial hypertension (PAH) in connective tissue disease-associated PAH (CTD-PAH) patients. Goal(s): The goal is to estimate mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) accurately using CMR metrics, with right heart catheterization (RHC) as the gold standard. Approach: Correlations between CMR and RHC parameters were assessed, and predictive models for mPAP and PVR were developed. Results: Strong correlations were observed between RHC and CMR metrics. Predictive CMR models were established for both mPAP and PVR, offering potential clinical applications. Impact: CMR parameters can be used to estimate mPAP and PVR in patients with CTD-PAH, potentially providing a noninvasive method for assessing pulmonary arterial hemodynamics during CTD-PAH management.
Slice-to-Volume 4D flow MRI in pediatric patients with congenital heart disease
Authors: Goolaub Datta Singh , Beland Valerie , Portnoy Sharon , Yoo Shi-Joon , Lam Christopher , Macgowan Christopher
Published: November 2024

Motivation: In the absence of injected contrast agent, the quality of magnitude data from traditional 4D flow techniques can be poor, making structural visualization and blood vessel segmentation challenging. Goal(s): Slice-to-volume 4D flow data has inherently high signal in blood vessels owing to in-flow effects. We apply slice-to-volume 4D flow in pediatric patients and evaluate its accuracy. Approach: 7 pediatric patients were imaged with slice-to-volume 4D flow. Dynamic magnitude reconstructions and angiograms were assessed. The flow accuracy was evaluated using traditional 2D phase contrast MRI. Results: Slice-to-volume 4D flow provided accurate flow quantification along with high quality anatomical and angiographic visualisations without contrast injection. Impact: Volumetric flow imaging was performed using slice-to-volume 4D flow in pediatric patients. The technique provided accurate flow quantification along with high quality anatomical and angiographic visualisations without contrast injection.
Optimized T2 Preparation in Non-Contrast MR Angiography for Improved Visualization of Pulmonary Vessels in Children at 3.0T
Authors: Yoneyama Masami , Isaak Alexander , Hart Christopher , Katemann Christoph , Weber Oliver , Attenberger Ulrike , Luetkens Julian , Zhang Shuo
Published: November 2024

Motivation: Signal loss in non-contrast-enhanced thoracic MRI due to off-resonance artifacts precludes evaluation of pulmonary vessels, particularly in children with complex/turbulent flows at high field. Goal(s): Our goal was to restore the signal and reduce artifacts for improved visualization of pulmonary vessels at 3.0T. Approach: We introduced a T2prep pulse with 16 composite refocusing pulses “MLEV16” with shorter refocusing interval and applied it in patients with congenital heart disease at 3.0T, in comparison to standard T2prep pulse using MLEV4. Results: Visualization of the pulmonary vessels was clearly improved using the MLEV16 pre-pulse compared to standard MLEV4 T2prep at 3.0T. Impact: Non-contrast-enhanced thoracic MRI with MLEV16 pre-pulse for T2 preparation permits improved visualization of pulmonary vessels for clinical evaluation, a primary need in areas where pediatric congenital heart disease is common and high-field MRI at 3.0T becomes more accessible.
SNAKE-fMRI: A modular fMRI simulator from the space-time domain to k-space data and back
Authors: Comby Pierre-Antoine , Vignaud Alexandre , Ciuciu Philippe
Published: November 2024

Motivation: fMRI is a powerful tool for neuroimaging, but its optimization in vivo is complicated due to limited reproducibility. Simulation setup can help, but current solutions lack flexibility, control, or efficiency. Goal(s): Develop a versatile and efficient fMRI simulator generating realistic fMRI data under various conditions: SNR levels, acceleration factors, spatiotemporal resolutions, noise, and artifact sources. Approach: We propose SNAKE-fMRI, a modular, open-source fMRI simulator that operates from image to k-space and vice-versa. It can generate 3D+time k-space and images, mimicking the entire fMRI acquisition process, with potential k-t accelerations. Results: We showcase the use of SNAKE-fMRI on a non-Cartesian k-t accelerated scenario. Impact: With SNAKE-fMRI as an open-source, versatile, and efficient fMRI simulator, researchers can generate realistic fMRI data under a controlled and fully reproducible setup, enabling new advancements in fMRI acquisition and reconstruction methods.
Multi-echo fMRI at 7T in infants
Authors: Moser Julia , Weldon Kimberly , Sung Sooyeon , Sadeghi-Tarakameh Alireza , Madison Thomas , Pham Hannah , Lundquist Jacob , Auerbach Edward , Adriany Gregor , Eryaman Yigitcan , Nelson Steven , Fair Damien , Elison Jed , Yacoub Essa
Published: November 2024

Motivation: Imaging infants with traditional voxel sizes is suboptimal due to their smaller brains. 7T imaging allows for higher spatial resolutions, while multi-echo fMRI provides optimal contrast across the brain. Goal(s): Establish the feasibility of high-resolution multi-echo fMRI in infants at 7T. Approach: Acquire data in the same infant at 3T/7T within the same week, allowing for direct comparisons, while also considering unique safety guidelines for 7T infant imaging. Results: Initial data demonstrate 3T/7T multi-echo fMRI in the same infant, establishing the feasibility of high-resolution ME-fMRI at 7T in infants with high contrast, sensitivity, and stronger functional connections. Impact: This first demonstration of multi-echo fMRI at 7T, including the use of voxel volumes (1.6 mm3) that are half the volume of what is normally used in 3T infant fMRI (2.0 mm3), promises opportunities to advance developmental neuroimaging.
Cerebellar atrophy and cerebellum-cerebral circuits associated with freezing of gait in patients with multiple system atrophy
Authors: Yang Huaguang , Liu Weiyin , Wen Zhi , Li Liang , Zha Yunfei
Published: November 2024

Motivation: The objective of this study was to evaluate the role of cerebellum in gait freezing pathophysiology in multiple system atrophy. Goal(s): Obtain neuroimaging evidence for clinical understanding of cerebellum role in MSA patients with FOG injury. Approach: A SUIT method was used to obtain cerebellum subregion gray matter alterations. In addition, seed-based FC was used to evaluate abnormal cerebello-cortical circuits. Spearman’s correlation analysis was used to evaluate cerebellum structural changes, cerebello-cortical circuit abnormality, and freezing severity. Results: MSA-FOG patients showed an abnormal cerebellum atrophy in subregion VI and VIII,Cerebellar-cortical “executive-control” and “visual-auditory” networks are associated with FOG in MSA. Impact: This study provided neuroimaging evidence for clinical understanding of cerebellum role in MSA patients with FOG injury
Cortical and subcortical proprioceptive contribution to oculomotor control in humans
Authors: Balslev Daniela , Keith Graeme , Hardaker Ross , Crabbe Frances , Fracasso Alessio
Published: November 2024

Motivation: The role of proprioception in controlling the movement of the eyes is currently unknown. Goal(s): To investigate cortical and subcortical activity in response to a proprioceptive stimulation task. Approach: 7T fMRI was used to measure BOLD signal in the whole cortex and the brainstem while volunteers performed a previously published proprioceptive task. Results: BOLD response was measured in the spinal trigeminal nucleus and the central sulcus/postcentral gyrus, as well as the abducens nuclei, frontal eye fields, supplementary eye fields and the cerebellum. Impact: A better understanding of the role of proprioception in eye movement control, can open up new avenues for research into the neural mechanisms underlying disorders of eye position and movement like childhood strabismus.
Thalamic Connectivity and its Role in Resilience to Trauma: Insights from Ultra-High-Field MRI at 7T
Authors: Khudeish Nibal , Rajkumar Ravichandran , Ramkiran Shukti , Sawalma Abdulrahman , Veselinović Tanja , Shah Jon , Neuner Irene
Published: November 2024

Motivation: To discern why some individuals develop stress-related disorders post-trauma while others don't, focusing on the role of thalamus in emotional regulation and resilience. Goal(s): Investigate thalamic functional connectivity differences in trauma-exposed individuals to identify neural mechanisms of resilience. Approach: Acquired MRI data from 35 Syrian refugees using a 7T scanner, analyzed for trauma-related connectivity differences via seed-to-voxel thalamic analysis with the CONN toolbox, informed by RS-25 and HTQ questionnaires to distinguish between asymptomatic and symptomatic groups. Results: Significant right thalamic connectivity differences were found, indicating potential neural resilience correlates and adaptive changes in sensory-motor processing related to PTSD symptom severity. Impact: This study enhances our understanding of trauma's neural basis and resilience, potentially directing new therapeutic strategies targeting thalamic connectivity to prevent stress-related disorders, thereby improving trauma care and mental health outcomes. Ref.
Functional Connectivity and Tract Integrity of the Ventral Tegmental Area in Parkinson’s Disease with Depressive Symptoms
Authors: Bhasin Srijan , Hsu Wei-Jing , Seow Pohchoo , Welton Thomas , Hartono Septian , Chen Celeste , Lee Weiling , Chai Pik Hsien , Tan Louis , Tan Eng King , Chan Ling Ling
Published: November 2024

Motivation: The ventral tegmental area (VTA) is theorized to contribute to the unique pathogenesis of depressive symptoms in Parkinson’s Disease (PD) but remains understudied. Goal(s): We aim to characterize the functional and structural connectivity changes in the VTA as they relate to depressive symptoms in PD. Approach: Resting state functional MRI and correlational tractography approaches were used to map the functional connectivity and tract projection changes associated with increased depressive symptoms in 54 patients and 100 controls. Results: The left VTA was found to have functional connectivity changes and tract profiles that correlate with clinical symptoms in manners unique to the PD subgroup. Impact: This study supports the idea of the ventral tegmental area playing a role in and potentially becoming a therapeutic target for the unique pathogenesis of depressive symptoms in patients with Parkinson’s disease.