bluuebunny/crossref_metadata_2025 huggingface dataset:
Volumetric abnormalities in thalamic subnuclei in drug-naive patients with major depressive disorder
Authors: Wang Yidan , Hu Xinyue , Zhang Lianqing , Li Hailong , Gao Yingxue , Tang Mengyue , Wang Yingying , Bao Weijie , Zhou Zilin , Huang Xiaoqi
Published: November 2024

Motivation: To investigate the specific changes of volumetric differences in Major Depressive Disorder (MDD) and healthy controls (HC) including their relationships with clinically related behavioral phenomena. Goal(s): To investigate volumetric differences in the thalamic subnuclei of untreated MDD patients and HC groups. Approach: We collected high-resolution 3D T1-weighted images from untreated MDD patients and age- and sex-matched healthy controls. Results: No significant volume differences of the bilateral thalamus as a subnuclei between MDD patients and healthy controls. Found age-by-diagnosis interactions for specific thalamic subnuclei. Partial correlation analyses show several left thalamic subnuclei showed positive correlations with HAMD-17 scores and cognitive disturbance scores. Impact: The study offers valuable insights into thalamic subnuclei changes and their impact on MDD. These findings underscore the significance of examining specific thalamic subnuclei and their potential impact on MDD's development.
Quantitative analysis of MRI-visible perivascular spaces in schizophrenia
Authors: Yu Hagyeong , Ryu Changmin , Kang Junghwa , Nam Yoonho , Lee Tae Young
Published: November 2024

Motivation: Perivascular spaces(PVS) are fluid-filled spaces that surround blood vessels in the brain. While dilated PVS(dPVS) play an important role, investigations into dPVS in schizophrenia are poorly understood. Goal(s): In this study, we aim to explore the potential of dPVS quantification as a biomarker for schizophrenia. Approach: For volumetric assessment, we segmented the dPVS in the white matter(WM) and basal ganglia(BG), and calculated the volumes and numbers of dPVS for each subject. Results: Our findings reveal differences in dPVS numbers and volumes among schizophrenia subgroups, especially in treatment-resistant schizophrenia(TRS) which showed smaller dPVS volumes compared to other groups in both WM and BG. Impact: Our study offers insights into the potential of dPVS quantification as a biomarker for schizophrenia. We observed differences in total dPVS volumes and number of dPVS components between different schizophrenia subgroups and found significant results especially in TRS.
Exploring connectivity and microstructural recovery following detoxification in individuals suffering from Alcohol Use Disorder
Authors: Dausort Manon , Delinte Nicolas , Salavrakos Melissa , Dricot Laurence , de Timary Philippe , Macq Benoît
Published: November 2024

Motivation: Alcohol use disorder (AUD) is a widely spread disorder responsible for 6% of global mortality. Alcohol affects a substantial portion of the population in various aspects and part of these changes may be related to brain modifications. Goal(s): To identify the effects of alcohol withdrawal on the brain and their link with symptom improvement. Approach: Combination of connectivity matrices and microstructural models based on diffusion MRI tested during withdrawal period. Results: The study of global brain connectivity revealed six connections, four of which also showed microstructure changes during withdrawal that were beneficial for recovery in areas heavily affected by increased alcohol consumption. Impact: We presented an exploratory way to evaluate the effects of short-term withdrawal using connectivity and microstructural models based on diffusion MRI. It revealed four brain connections that deserve to be studied in greater depth in the case of this pathology.
Eight weeks of bright light therapy increases myelin density in the posterior thalamic radiation in young adults with subthreshold depression
Authors: Chen Guanmao , Tang Guixian , Cui Wei , Wang Ying
Published: November 2024

Motivation: Subthreshold depression (SD) is a significant risk indicator of major depressive episodes. The inhomogeneous magnetization transfer (ihMT) technique has not been used to probe myelin abnormalities and its response to bright light therapy (BLT) in SD. Goal(s): In this study, we used ihMT technique to investigate myelin integrity in a relatively large sample size of university students with SD. Approach: The qihMT and ihMTR values of 50 white matter (WM) fibers were compared between SD and HCs. Results: Macromolecular disruption of myelin in the posterior thalamic radiation (PTR), sagittal stratum, and uncinate fasciculus might exist in the early stages of depression. Impact: These findings suggest the myelin impairments in the posterior thalamic radiation could be reversed by bright light therapy, which might be used as the potential neural target for bright light therapy in subthreshold depression.
Meta-Learning Enabled Score-Based Generative Model for 1.5T-Like Image Reconstruction from 0.5T MRI
Authors: Liu Congcong , Cui Zhuo-Xui , Cao Chentao , Liu Yuanyuan , Cheng Jing , Zhu Qingyong , Zhou Yihang , Zhu Yanjie , Wang Haifeng , Zheng Hairong , Liang Dong
Published: November 2024

Motivation: The high-field-like image reconstruction, mainstream efforts are primarily focused on high or ultra-high fields, lacking in the reconstruction of high-field-like images from low-field ones. Goal(s): This paper presented a model for reconstructing high-field-like MR images from low-field images with unpaired data. Approach: we execute a pairing using OT-driven CycleGAN, described as "teacher learning". Subsequently, we use a diffusion model to learn the joint distribution between high-field and low-field images, guiding the reconstruction from low-field to high-field. Results: The generation experiments of T1W and T2W surpass competing experiments, and the 3-fold acceleration experiment also demonstrates the superiority of the proposed method. Impact: The proposed method represents the first attempt in the reconstruction (acceleration and generation) of images from low-field to high-field. Its potential benefits for advancing overall healthcare standards could be significant.
TDI-Conditioned Diffusion Model for Resolution Enhancement of Diffusion-Weighted Images
Authors: Teng Yujun , Jiang Haotian , Liu Feihong , Rekik Islem , Ma* Jiquan , Chen* Geng
Published: November 2024

Motivation: Diffusion-Weighted Imaging (DWI) suffers from low resolution. Post-acquisition super-resolution can effectively enhance the resolution of DWIs.Goal(s): We propose a novel post-acquisition DWI super-resolution method based on the conditioned diffusion model.Approach: We design an effective condition based on Track Density Imaging (TDI), which contains rich high-resolution information. Furthermore, we consider low-resolution DWIs as another condition to preserve the original information of images. Results: Extensive experiments on HCP data show that our model is effective in DWI super-resolution and outperforms the cutting-edge models.Impact: To enhance the resolution of DWIs, we propose a super-resolution method based on conditioned diffusion model. This is beneficial to the clinical practice of DWI.
Beyond Differences: Cross-Subject and Cross-Dataset fMRI Brain Decoding of visual stimuli
Authors: Ferrante Matteo , Boccato Tommaso , Ozcelik Furkan , VanRullen Rufin , VanRullen Rufin , Toschi Nicola
Published: November 2024

Motivation: Brain decoding has been limited by the need for large data amounts and subject-specific methodologies. Current techniques require extensive scanning, which is costly and time-consuming, restricting their applicability. Goal(s): The study aims to establish a novel, more efficient approach for cross-subject brain decoding of visual stimuli. Approach: Using the NSD we applied regularized ridge regression to align brain activity across different subjects on common stimuli representations, employing the state-of-the art Brain-Diffuser pipeline for decoding and image reconstruction. Results: The ridge regression alignment method surpassed others, enabling consistent cross-subject decoding with significantly reduced data—demonstrating feasibility and a potential 90% scan time reduction. Impact: A reliable technique for cross-subject, -scanner and -field strength alignment can pave the way for efficient brain decoding without the need for extensive data collection and/or ultra-high field strengths.
Focused MRI Segmentation: Leveraging Diffusion Models for Brain Tumor Segmentation in Low-Resolution Areas
Authors: Monroy Luis Rivera , Wang Tianqi , Belagiannis Vasileios , Maier Andreas
Published: November 2024

Motivation: Glioblastoma, the most prevalent and aggressive adult brain tumor, presents a therapeutic and monitoring challenge due to its diverse morphology and composition. Goal(s): This study explores the efficacy of utilizing denoising diffusion models with the widely adopted U-Net architecture for enhanced segmentation performance. Approach: The proposed framework notably improves the segmentation of the tumor, especially the core. This enhancement facilitates an advanced understanding of complex cases and potentially impacts specialist interventions. Results: Our findings present promising results for further research into more intricate glioblastoma cases, thereby aiding in developing sophisticated, targeted treatment strategies for this disease. Impact: This study advances U-Net architecture by integrating denoising diffusion models and specialized loss functions, elevating the precision of low-resolution brain tumor segmentation, with an emphasis on balancing improved accuracy against uncertain predictions.
Unsupervised Neural Network for Super-Resolving Non-Contrast-Enhanced Whole-Heart MRI Using REACT
Authors: Maciel Corbin , Zou Qing
Published: November 2024

Motivation: Three-dimensional (3D) whole-heart MRI requires long scan times and the sequence used to acquire such scans is susceptible to banding artifacts. Goal(s): The goal of this study was to develop an unsupervised super-resolution neural network for 3D whole-heart MRI. Approach: The data used in this study was acquired using a modified Relaxation-Enhanced Angiography without Contrast and Triggering (REACT) sequence. A neural network referred to hereafter as the Super-resolution Neural Network (SRNN) was developed to super-resolve 3D MRI data. Results: The SRNN allows us to acquire lower-resolution scans, thus decreasing scan time, and provides improved image quality after performing super-resolution. Impact: The results of this study show that super-resolution offers a viable option to decrease scan time and improve overall image quality in 3D whole-heart MRI.
Pretraining using masked language modeling improves label noise robustness on the metadata standardization task
Authors: Duffy Ben , Chamberlain Ryan
Published: November 2024

Motivation: The lack of standardization in MRI metadata increases radiologist workload. Goal(s): To demonstrate an approach to standardize the image contrast and the body part examined information in the DICOM header and to understand the benefits of self-supervised pretraining on the metadata standardization task in the presence of label noise. Approach: Masked language modeling was used for pretraining. At the fine-tuning stage, a transformer model was used to predict the image contrast and body part from both the text and numerical DICOM tags. Results: Pretraining improves robustness to label noise, with there being no loss in performance at 20% label noise. Impact: Pretraining using masked language modeling is effective at rendering a metadata stanardization system robust to label noise. Such a system can be used to standardize MRI metadata and therefore reduce radiologist workload. Future work should investigate class conditional label noise.
Tissue Metabolomics Characterization of Human Valve Diseases using NMR spectroscopy
Authors: Palleti Rajashekar , Kumar Pawan , Kumar Pradeep , Chakraborty Sandeep , Mewar Sujeet , Arva Sudheer , Jayasundar Rama , Narang Rajeev
Published: November 2024

Motivation: Heart valve disease (HVD) is a multifactorial process and its pathophysiology has not been fully understood. Goal(s): To investigate and determine the metabolite tissue using the 1H-NMR based metabolomics study to discriminate the aortic valve and mitral valve. Approach: proton NMR spectroscopy Results: The results obtained from PLS-DA and VIP score plots of metabolites in tissue showed a separation between patients with aortic valves and mitral valves. Impact: The present study revealed discrimination of metabolic profiling of tissue of aortic valve patients from mitral valve replacement implying that 1H-NMR-based metabolomics may provide an insight into understanding the potential metabolic alteration.
IRON-HEART: Cardiac and skeletal muscle energetics in chronic heart failure and iron deficiency
Authors: Birkhoelzer Sarah , Arvidsson Per , McGing Jordan , Jafarpour Mehrsa , Henry John , Yeung Kylie , Axford Aaron , Shinozaki Ayaka , Grist James , Tyler Damian , Rider Oliver , Rayner Jenny , Valkovic Ladislav
Published: November 2024

Motivation: Determining the impact of iron repletion on muscle energetics in non-ischaemic cardiomyopathy with reduced ejection fraction (EF). Goal(s): Use cardiac and skeletal muscle 31P MRS to assess cardiac and skeletal muscle energetics pre and post iron repletion therapy. Approach: Participants and ID underwent CMR to assess cardiac function, MRS to assess Phosphocreatine to Adenosine triphosphate (PCr/ATP) ratio in cardiomyocyte and relation to skeletal muscle PCr consumption, end-exercise intracellular pH and PCr recovery rate before and after Ferric carboxymaltose (FCM). Results: FCM improves ejection fraction, 6-minute-walk-distance. It didn’t change in myocardial resting or dynamic energetics or skeletal muscle oxidative metabolism. Impact: Iron infusion didn’t change PCr/ATP, however increased left ventricular ejection fraction, therefor increase ATP requirement. We hypothesise that iron replacement resulted in increase in energy efficiency, or improved flux through Creatine Kinase, which was not assessed during this study.
Characteristics of myocardial tissue triglyceride content detected by MRS in Duchenne muscular dystrophy
Authors: Xu Ting , Xu Huayan
Published: November 2024

Motivation: Myocardial fat infiltration is the key pathological features of Duchenne muscular dystrophy associated cardiomyopathy. Magnetic resonance spectroscopy is a valuable method for detecting the in vivo changes of cardiac metabolism noninvasively. Goal(s): To investigate the characteristics of myocardial tissue triglyceride content in DMD by non-invasive MRS. Approach: Twenty patients with DMD and Controls underwent cardiac MRI, including spectral sequence. The peak area and the area under the peak of H2O and TG in each voxel were calculated. The t-test whether the sample mean was significant. Results: The difference of TG content between DMD children normal group and the two groups was statistically significant. Impact: Cardiac magnetic resonance spectrum can reflect myocardial triglyceride relative quantity for myocardial lipid content in the different stages of disease on how to change.
Deep Learning based Acquisition and Reconstruction for Cardiac Magnetic Resonance Imaging in Patients with Chronic Kidney Disease
Authors: Lu Xuefang , Liu Weiyin , Yan Yuchen , Zha Yunfei
Published: November 2024

Motivation: Cardiac abnormalities and arrhythmias increased risk of cardiovascular mortality especially in patients with Chronic Kidney Disease (CKD). Goal(s): To provide objective and subjective assessment in supproting the feasibility of deep learning acqusition and reconstruction cardiac magnetic resonance (CMR) imaging in patients with Chronic Kidney Disease (CKD). Approach: Qualitative and quantitative evaluation of Sonic DL-based CMR images including breath-hold acquisition within one-beat-interval, free-breathing acquisition in comparison with traditional cine images. Results: Sonic DL significantly accelerated acuqisition time (e.g. 11 seconds) but offered diagnosis-suffcient image quality and reliable strain values ompared to conventional sequences. Impact: Sonic DL cine MRI showed equivalent image quality to conventional one, offered reliable strain values for diagnosis of a CKD patient lack of breath-hold ability and presentce with arrhythmias. Even it acquire a whole heart cine image in 11 seconds.
Diffusion Tensor Phenomapping of Local Microenvironments in the Pressure Overloaded Human Heart
Authors: Rock Christopher , Chen Iris , Philip Anne , Keil Boris , Nguyen Christopher , Sosnovik David
Published: November 2024

Motivation: DTI data in the heart are currently averaged to yield per-patient values that cannot detect local variations in the microstructural microenvironment. Goal(s): We aimed to develop a voxel-based phenomapping approach to cluster the voxels in the myocardium into distinct groups based on their microstructural properties. We then used the approach to compare subjects with aortic stenosis (AS) to age-matched controls (CTL). Approach: A population matrix of voxels was created using z-score normalization and evaluated with k-means clustering (k=4). Results: 4 distinct clusters of voxels were present, each with different microstructural properties. No significant differences were seen between the AS and CTL subjects. Impact: An approach to perform voxel-based phenomapping of DTI data in the heart was developed and used to classify the voxels in the myocardium into distinct microstructural clusters.
Simultaneous 3D whole-heart T2 mapping and coronary angiography (3D-T2A)
Authors: Morita Kosuke , Yoneyama Masami , Oda Seitaro , Kidoh Masafumi , Uetani Hiroyuki , Nakaura Takeshi , Hatemura Masahiro , Hirai Toshinori
Published: November 2024

Motivation: We focused on the similarity between 3D T2prep T2 mapping and whole-heart MRCA and developed a new sequence for simultaneous T2 mapping and MRCA sequence. Goal(s): Our goal of this study is to validate the simultaneous acquisition of 3D T2 mapping with whole heart MRCA. Approach: We visually assessed the image quality of 3D T2 mapping and MRCA. T2 values were compared with 2D T2 mapping (2D-GRASE). Results: This method, which enables simultaneous acquisition of 3D T2 mapping and MRCA, can provide stable image quality and T2 values. Impact: Our method, which enables simultaneous acquisition of 3D T2 mapping and MRCA, can provide stable image quality and T2 values, and will be of great benefit in future imaging.
Differentiating Myocardial Scar and Viable Myocardium without Gadolinium Contrast using Native Cardiac MRF Maps and Synthetic Images
Authors: Bazan Ana Saavedra , Hamilton Jesse , Kaplan Sydney , Rajagopalan Sanjay , Rashid Imrad , Seiberlich Nicole
Published: November 2024

Motivation: Late Gadolinium Enhancement (LGE) imaging is the gold-standard CMR imaging for distinguishing heart tissue viability. However, not all patients can receive gadolinium-based contrast agent. Native T1 have been proposed in place of LGE. Goal(s): This study explores pre-contrast cardiac MRF T1 and T2 measurements as potential indicators of ischemic myocardial scar. Approach: Native T1 and T2 values were measured using cMRF in eleven ischemic patients using ROIs in both scar and non-scar myocardial tissue identified through LGE imaging. Results: Native cMRF measurements differ between scar and non-scar areas. Synthetic images from these maps highlight scar tissue, offering a potential LGE imaging alternative. Impact: Native cMRF T1 and T2 maps and synthetic images derived from these maps may enable differentiation of scar tissue from viable myocardium without the need for gadolinium-based contrast agents.
Evaluation of Local Microstructural Gradients in the Myocardium of Subjects with Severe Aortic Stenosis.
Authors: Rock Christopher , Chen Iris , Philip Anne , Keil Boris , Nguyen Christopher , Sosnovik David
Published: November 2024

Motivation: Diffusion tensor imaging of the heart can be performed with sub-mm resolution. However, established metrics do not fully take advantage of this improved resolution. Goal(s): We aimed to determine whether local gradients in helix angle (HA) could be calculated and used to characterize the microstructural response of the heart to the load imposed by aortic stenosis. Approach: Voxel-wise maps of radial, circumferential, minimum and maximum HA gradients were generated. Results: The radial HA gradient was reduced in aortic stenosis, but microstructural coherence was well preserved in these patients despite a marked increase in the thickness of the myocardium. Impact: DTI of the heart with sub-mm in-plane resolution allows maps of local HA gradients to be generated, providing novel insights into the microstructure of the heart.
Exploring age-related alterations in brain metabolite levels in healthy adult women using 1H MRS at 3T: Effects of exposure to early-life stress
Authors: Mekle Ralf , Fleck Lara , Bauer Martin , Deelchand Dinesh , Buss Claudia , Entringer Sonja , Fiebach Jochen , Endres Matthias , Heim Christine
Published: November 2024

Motivation: Adversity experienced during early life termed early-life stress (ELS) might increase the risk for neuroinflammation and neurodegenerative disorders in the adult human brain. An enhanced understanding of these relationships will aid in diagnosis and intervention. Goal(s): Our goal was to investigate whether ELS is associated with changes in brain metabolism by using 1H MR spectroscopy. Approach: The interaction between metabolite concentrations obtained from MRS, acquired in adult women, age, and scores of ELS was modeled using non-linear statistics. Results: Higher concentrations with increasing age in individuals exposed to ELS were found for specific metabolites suggesting long-term effects of ELS on the human brain. Impact: Understanding the role of early-life stress (ELS) in driving neuroinflammatory processes and identification of specific biomarkers to assess the risk for accelerated cognitive decline and neurodegenerative disorders in individuals exposed to ELS will aid in early identification and targeted interventions.
Investigating Cortical Neurochemical Concentrations in Painful Knee Osteoarthritis using Magnetic Resonance Spectroscopy
Authors: Leech Samantha , DeMayo Marilena , Bell Tiffany , Batuyong Eldridge , Clark Marcia , Schneider Geoff , White Neil , Millar Kayla , Hasselaar Charley , Ng Richard , Manske Sarah , Harris Ashley
Published: November 2024

Motivation: Alterations in the brain are suggested to contribute to chronic arthritis pain, however there is limited research on the specific neurochemicals and brain regions involved in this process. Goal(s): We aimed to identify neurochemicals and brain regions associated with chronic pain in knee osteoarthritis to understand the brain’s contribution to this condition. Approach: We used magnetic resonance spectroscopy to compare neurochemical levels in four pain-related brain regions between cohorts of patients with painful knee osteoarthritis and healthy controls. Results: Significantly lower levels of GABA and myoinositol in the anterior cingulate cortex in the knee osteoarthritis group suggests potential disrupted inhibitory processes and neuroinflammation. Impact: Patients with painful knee osteoarthritis exhibited significantly lower levels of GABA and myoinositol in the anterior cingulate cortex compared to healthy controls. These findings illuminate the anterior cingulate cortex as a potential therapeutic target for knee osteoarthritis pain management.
Mapping of cerebral metabolite concentrations in brain tumors using 1H-MRSI and quantitative MRI
Authors: Thomas Dennis , Alcicek Seyma , Manzhurtsev Andrei , Hattingen Elke , Wenger* Katharina , Pilatus* Ulrich
Published: November 2024

Motivation: Absolute quantification of the 1H MRS metabolites remains a challenge for 2D MRSI, due to long acquisition times for the unsuppressed water reference and the multiple biases present due to relaxation and inhomogeneity. Goal(s): To propose a water reference method combining single voxel STEAM and quantitative MRI (qMRI). Approach: The method is demonstrated and tested against a standard water referencing method on one healthy subject. Its application is demonstrated in a brain tumor patient. Results: Apart from obtaining absolute metabolite concentrations, corrected for all water relaxation times, 4 qMRI maps (PD, T1, T2* and QSM) maps are also generated. Impact: We propose a method for absolute quantification of cerebral metabolites in 2D MRSI by combining STEAM and quantitative MRI. The method is tested against a reference method in a healthy subject and its application demonstrated for a brain tumor patient.
Acceleration of preclinical 1H-FID-MRSI in vivo acquisitions at 14.1T using Compressed Sensing
Authors: Alves Brayan , Mosso Jessie , Lê Thanh , Briand Guillaume , Simicic Dunja , Lanz Bernard , Cudalbu Cristina
Published: November 2024

Motivation: Preclinical Magnetic Resonance Spectroscopic Imaging offers valuable spatial information about metabolite content in the rodent brain, but is subjected to low signal-to-noise ratio and long acquisition time. Goal(s): Our goal was to accelerate preclinical 1H-MRSI by implementing and validating compressed sensing acceleration schemes to enable accurate acquisitions under 10 minutes. Approach: Free Induction Decay MRSI sets were acquired on the rodent brain using compressed sensing with different acceleration factors and k-space center acquired volumes. Results: Metabolic maps and regional differences were preserved with higher acceleration factors, going from 13 minutes to 6.5 minutes acquisition and lower. Impact: 1H-MRSI using compressed sensing, with its achieved 6.5 minutes acquisition, could be used for effective and reliable transversal metabolic studies of neurodegenerative diseases within preclinical models, such as the bile duct ligation rat model for hepatic encephalopathy.
High-field downfield magnetic resonance spectroscopic imaging in the human brain
Authors: Özdemir İpek , Etyemez Semra , Barker Peter
Published: November 2024

Motivation: Downfield (DF) MR spectroscopic imaging (MRSI) is a promising new metabolic imaging technique that has previously been demonstrated in the human brain at 3T. This abstract describes initial results of 3D DF-MRSI at 7T. Goal(s): To implement and test 3D DF-MRSI at 7T. Approach: The 3D DF-MRSI pulse sequence was adapted for 7T and tested on 4 healthy volunteers. Results: High-field DF-MRSI with 0.7 mm3 nominal voxel resolution is feasible. Concentration and uncertainty estimates for the 9 downfield peaks and combined amide resonances from selected voxels were not significantly different, except for DF6.83 which was significantly lower in the CSO than DLPFC (p=0.007). Impact: High-field DF-MRSI should now be able to spatially map the exchangeable protons in human brain within clinically acceptable times and accuracy to be used in future studies of brain tumors or other neuropathological disorders.
Metabolic Atlas of the Human Cerebrum derived from 1H MRSI at 9.4T
Authors: Wright Andrew , Ziegs Theresia , Henning Anke
Published: November 2024

Motivation: To provide a metabolic reference atlas for brain metabolite concentrations. Goal(s): Derive regional metabolite concentration estimates from the human brain. Approach: Brain 1H MRSI data were acquired from 10 healthy controls and quantitative metabolite maps were combined via transformation into MNI space to derive median metabolite maps. Regional metabolite concentration estimates were derived. Results: Brain metabolite maps and regional concentrations for 12 human brain metabolites have been derived. Impact: A reference standard for metabolic brain MRI was established.
Linewidth and lineshape bias in modelled outcomes from GABA-edited 1H MRS
Authors: Craven Alexander , Ersland Lars , Bell Tiffany , Harris Ashley , Hugdahl Kenneth , Oeltzschner Georg
Published: November 2024

Motivation: The study addresses a gap in literature concerning the impact of spectral linewidth and lineshape differences on GABA+ estimates. Goal(s): To assess the degree to which differences in linewidth/lineshape may confound GABA+ estimates. Approach: In-vivo GABA+-edited spectra (N=222) were quantified with six modelling algorithms after applying varying degrees of Lorentzian and Gaussian linebroadening. Results: Most algorithms showed strong negative associations between amount of Lorentzian linebroadening and GABA+ estimate (2-5% per Hz LB), consistently across datasets. Gaussian linebroadening showed contrasting, substantially weaker associations. In functional applications and cases of differing T2 relaxation between regions or subject groups, these results indicate a potentially significant confound. Impact: Comparing metabolite concentration estimates across different anatomical regions, subject groups or experimental conditions requires appropriate handling of differences in linewidth and linebroadening mechanisms. We demonstrate that several modelling algorithms have linebroadening biases, differing by lineshape, that may confound findings.
Constrained Optimized Water Suppression (COWS) for Macromolecule Measurements with 1H Magnetic Resonance Spectroscopy
Authors: Igwe Kay , Landheer Karl , Gajdosik Martin , Juchem Christoph
Published: November 2024

Motivation: A new water suppression module optimized for both macromolecule detection and short repetition time sequences such as magnetic resonance spectroscopic imaging. Goal(s): To have an efficient, flexible, water suppression algorithm where macromolecules can be measured. Approach: Single voxel localization by adiabatic selective refocusing (semi-LASER) measurement of macromolecules were conducted in the prefrontal cortex, posterior frontal (PFL) and occipital lobes. Both VAPOR and the customizable water suppression (COWS) algorithm were performed for each experiment. Results: Both WS methods performed well with residual water signals below the 2.01-ppm NAA singlet signals. COWS demonstrated better water suppression than VAPOR overall, especially in the PFL. Impact: A new customizable water suppression algorithm, COWS, was tested in vivo for improved efficiency and speed when compared to the gold standard (VAPOR).
Longitudinal reproducibility of 3D-FID-CRT-MRSI in the human brain at 3T and 7T
Authors: Eftekhari Zeinab , Shaw Thomas , Eckstein Korbinian , Strasser Bernhard , Niess Fabian , Hingerl Lukas , Bogner Wolfgang , Barth Markus
Published: November 2024

Motivation: A direct comparison of the longitudinal reproducibility of 3D FID-CRT-MRSI across 3T and 7T has not been performed. Goal(s): The aim was to determine the consistency of MRSI across these two field strengths in different brain regions. Approach: The same subjects were scanned twice within a week at both fields and intra-subject and inter-subject Coefficients of Variation (CV%) for three metabolite ratios in different brain regions were calculated. Results: The study found high reproducibility (CVs for most ROIs <10%) for both fields. 3T can provide sufficiently reproducible results by using larger voxel sizes and shorter measurement times. Impact: The results will impact researchers and clinicians using MRSI, providing them with a reproducible technique at a clinical field strength of 3Tand7T and can be a method for those focusing on larger brain regions or longitudinal monitoring of metabolite changes.
Analysis of MRS voxel placements in brain tumors performed by MRS experts
Authors: Lee Sangyoon , Branzoli Francesca , Andronesi Ovidiu , Chen Clark , Lin Alexander , Liserre Roberto , Melkus Gerd , Nguyen Thanh , Bolan Patrick , Marjańska Małgorzata
Published: November 2024

Motivation: There is no standardized way of prescribing MRS voxels in the lesion. This depends entirely on the MR operator’s expertise and opinion. Goal(s): Our goal was to analyze MRS voxel placements in brain tumors for quantitatively reliable and reproducible voxel placement. Approach: MRS experts placed voxels and visually scored their placements. Placements and scores were compared to tumor characteristics. Results: All experts showed a tendency to place the voxels to fill approximately 30% of voxels with tumor core for different participants. The fraction of tumor core in voxels showed a correlation of 0.76 to the fraction of tumor core in the whole tumor. Impact: Quantitative analysis of MRS voxel placement shows that MRS experts deemed a voxel properly placed when tumor core was adequately included, suggesting widely applicable and objective method of voxel placement and assessment for non-experts in clinical settings.
Effect of LCModel basis set B0 frequency on MRS quantification
Authors: Deelchand Dinesh , Öz Gülin
Published: November 2024

Motivation: The actual B0 resonance field of 3T scanners is different between the three major MR vendors. Goal(s): Here, we report the effect on metabolite quantification of using basis sets at different B0 fields than the B0 frequency of the measured in vivo MRS data. Approach: Basis sets were simulated at thirteen different B0 fields. Semi-LASER MRS data measured from the posterior cingulate cortex at 3T were fitted using LCModel. Results: Results show that biases in metabolite concentrations were within 1% when the basis set B0 frequencies were within ±0.5 MHz from the actual scanner frequency. Impact: A single sequence-specific basis set can be used to analyze harmonized spectroscopic data collected on clinical 3T scanners from different vendors that operate at different frequencies.
Cartesian spirals: An alternative to radial imaging for 4D-MRI in MR-guided radiotherapy
Authors: Lecoeur Bastien , Nair Prashant , Westley Rosalyne , Feng Li , Oelfke Uwe , Luk Wayne , Wetscherek Andreas
Published: November 2024

Motivation: 4D-MRI could improve online MR-guided radiotherapy treatments on the MR-Linac, but long reconstruction times hinder clinical implementation. Goal(s): To reconstruct and evaluate respiratory-correlated and time-resolved 4D-MRIs from different acquisitions. Approach: We reconstructed 4D-MRIs using the XD-GRASP and GRASP-Pro algorithms from a clinical protocol (stack-of-stars) and a new Cartesian spiral sequence. We compared the reconstructions regarding diaphragm motion. Results: Respiratory-resolved 4D-MRIs were reconstructed under 4 minutes from current acquisitions. Time-resolved 4D-MRIs from clinical acquisitions showed significant artefacts limiting the achievable temporal resolution which can be overcome by using a different acquisition. Impact: Respiratory-correlated 4D-MRIs reconstruction times were compatible with online radiotherapy constraints for pancreatic cancer patients on the MR-Linac. Reaching high temporal resolutions in reconstructing time-resolved 4D-MRIs is not currently possible from the current clinical protocol.
Improving the spatial-temporal fidelity and resolution of dynamic MRI using complex-valued spatial-temporal super-resolution method
Authors: Sun Duohua , Han Silu , Dieckhaus Laurel , Hutchinson Elizabeth , Chen Nan-kuei
Published: November 2024

Motivation: To improve image quality and spatial-temporal resolution of T2*-weighted dynamic MRI in applications such as MRI-guided focused ultrasound surgery, resulting in more effective diagnostic and treatment outcomes. Goal(s): Our goal is to present an innovative complex-valued spatial-temporal multi-band super-resolution technique, enhancing spatial-temporal resolution, signal-to-noise ratio (SNR) and minimizing susceptibility artifacts in T2*-weighted dynamic MRI. Approach: We highlight the susceptibility artifact through a hybrid simulation and design a multi-band-super-resolution sequence. We perform an experiment on phantom and the acquired data is reconstructed using our proposed method. Results: Hybrid simulation and reconstruction on phantom data demonstrate improvements in SNR, spatial-temporal-resolution, and reduction of susceptibility artifacts. Impact: Conventional magnitude-based super-resolution reconstruction exhibits signal loss due to susceptibility effects. Our proposed method integrating phase in reconstruction shows an improvement in SNR, spatial-temporal resolution, and a reduction of susceptibility artifacts.
Zero-shot self-supervised deep learning reconstruction for abdominal DCE MR multitasking
Authors: Chen Zihao , Sheng Ruofan , Jin Kaipu , Han Shihong , Xu Jian , Zeng Mengsu , Li Debiao , Liu Qi
Published: November 2024

Motivation: Deep learning (DL) MR multitasking reconstruction can reduce the reconstruction time, but previous methods are supervised learning, which may learn artifacts from the reference images. Goal(s): Our goal was to develop a DL reconstruction method that can improve image quality beyond supervised DL and conventional iterative reconstruction. Approach: We developed a zero-shot self-supervised deep learning method for DCE MR multitasking reconstruction. Results: With shorter reconstruction time than conventional iterative reconstruction, the proposed method obtained better image quality than both supervised DL and conventional iterative reconstruction methods. Impact: With the proposed method, DCE MR multitasking can have better image quality with shorter reconstruction time than previous iterative reconstruction, which is essential for the potential clinical application of the motion-resolved and high spatial-temporal-resolution abdominal DCE MR multitasking.
Extended Capabilities for multi-dimensional MR for Abdominal Radiation Therapy Planning
Authors: Chen Junzhou , Kong Qingle , Chen Yang , Deng Jie , Yang Wensha , Li Debiao , Christodoulou Anthony , Fan Zhaoyang
Published: November 2024

Motivation: Motion resolution of the original Multitasking 4D RTP MR sequence is not robust enough. Goal(s): To enhance motion robustness and introduce T1/T2 mappings of 4D abdominal RTP MR protocol. Approach: Estimation of explicit motion deformable vector fields to correct. Results: The proposed approach dramatically enhance motion robustness of MR multitasking in 4D MRI. Impact: The straight-forward explicit motion vector field estimation and application provides effective and robust motion correction .
Feasibility of 3D Reduced-FOV Multi-shot Isotropic DWI in Optic Nerves
Authors: Yuan Chenglang , Chen Shihui , Liang Liyuan , Xu Xiaorui , Xiong Hailin , Li Yi , Liu Tianbaige , Chang Hing-Chiu
Published: November 2024

Motivation: Conventional 2D DWI sequences suffer from several disadvantages, therefore hindering the clinical visual assessment of optic nerves. Goal(s): This study aims to enable a 3D reduced-FOV multi-shot isotropic DWI sequence for optic nerves DWI and verify its feasibility. Approach: The pulse sequence and corresponding reconstruction algorithm of 3D reduced-FOV 2-shot isotropic DWI was developed to achieve effective and accurate reconstruction of optic nerves. Results: Preliminary results have shown the feasibility of our method in depicting the optic nerves with high resolution and high fidelity, therefore potentially benefiting the clinical applications of optic nerves DWI. Impact: 3D reduced-FOV multi-shot isotropic optic nerves DWI shows superior advantages of high resolution and high fidelity compared with other conventional DWI sequences, which should be further investigated and applied for clinical applications of optic nerves.
A Preliminary Study on MRI Water Imaging-based Radiomics Nomogram to Identify Symptomatic Nerves in Primary Trigeminal Neuralgia Patients
Authors: Li hongjian , Zhang chuan , Li zeyong , Liu ying , Yang hanfeng , YANG Yu-Xin , HE Shi-Pei
Published: November 2024

Motivation: Addressing the diagnostic challenges of Primary trigeminal neuralgia (PTN) and exploring the potential of radiomics combined with clinical features for better accuracy. Goal(s): To establish an auxiliary diagnostic model for PTN using radiomic and clinical features. Approach: Retrospectively analyzed 116 patients with trigeminal neuralgia, extracting 1316 radiomics features using 3D slicer and studying 13 clinical features. Lasso regression, ICC analysis, univariate and multivariate logistic regression were used for analysis. Results: Combining radiomic and clinical characteristics improved the model's AUC values to 0.85. Atrophy of the trigeminal roots might be significant in PTN diagnosis. Impact: This study enhances PTN diagnosis, guiding clinicians with improved accuracy, potentially benefiting patients. It paves the way for further research on trigeminal root atrophy's role, optimizing treatment strategies and patient care.
Exploring the diagnostic performances of CISS and DESS in visualizing extracranial nerves and localizing parotid tumors
Authors: Fan Xiaoxue , Ding Changwei , Zhang Chen , Li Yuanrui , Hou Yang
Published: November 2024

Motivation: Identification of the spatial relationship between the parotid tumor and the extracranial segment of the facial nerve can facilitate preoperative planning. Goal(s): We compared image quality and diagnostic efficacy between double-echo steady-state with water (DESS) and constructive interference in steady-state (CISS) sequences. Approach: DESS and CISS sequences were used to determine the visibility of the extracranial segment of the facial nerve in healthy volunteers, then locate parotid tumors and facilitate patient diagnosis. Results: Compared with DESS images, CISS images more reliably showed the location of the facial nerve relative to the lesion in patients with parotid tumorsImpact: CISS demonstrates good visualization of the parotid branches (temporofacial and cervicofacial trunks) compared with DESS. Moreover, CISS is a reliable and direct method for identifying the locations of parotid tumors.
The peripheral branches of the trigeminal nerve: An illustrated article of neurogenic tumors imaging and related anatomy and pathway
Authors: wu haibo
Published: November 2024

Motivation: Trigeminal neurogenic tumors involving the peripheral branches are relatively rare, and valueable.Luckly,I collect many kind of neurogenic tumor including rare case. Goal(s): CT and MR imaging can illustrate related anatomy and pathway of three peripheral branches of the trigeminal neurogenic tumors. Approach: We obtained MR and CT images of all the adult Chinese patients during regular clinical trial with their informed consent. Results: Imaging features include irregular thickening and enhancement of the nerve, furthermore to clearly display supra-orbital, infra-orbital, and inferior alveolar nerves respectively.Surprisely,it also widened the neural foramen those neurogenic nerves pass through. Impact: A thorough understanding of its anatomy and pathwayis very important, both in diagnosis and treatment of tumors.It really provided a important clinical guiding for proper practice.
Spatiotemporally Encoded Single-Sided MRI with a Numerical Point-Spread Function Reconstruction
Authors: Sadinski Meredith , De Matos Gomes Muller , Nacev Aleksander , Grissom William
Published: November 2024

Motivation: Motivation: Single-sided MRI scanners offer excellent interventional access but require novel approaches to image acquisition. Goal(s): To generate distortion-free spatiotemporally encoded images with a single-sided low-field MRI scanner and validate the acquisitions in vivo. Approach: Spatiotemporally encoded images were collected in phantom and volunteer and reconstructed using a numerical PSF-based reconstruction. Results: Images of male and female subjects showed anatomic structures. Reconstruction with a numerical modeled PSF increased visibility of these structures and improved signal across the field of view in both phantom and human images relative to using a sinc-based PSF. Impact: This methodology can be used for translation of an xSPEN encoded sequence into clinical practice and aid other researchers facing similar reconstruction challenges.
Enhancing Self-Navigated Interleaved Spiral with ESPIRiT (eSNAILS)
Authors: Yong Xingwang , Fujita Shohei , Jun Yohan , Cho Jaejin , Liu Qiang , Zhang Yi , Bilgic Berkin
Published: November 2024

Motivation: Current methods for estimation of shot-to-shot phase variations in multi-shot DWI may not fully exploit the correlations in data. Goal(s): To propose a method which efficiently uses correlations between shots and coils to calculate composite sensitivities and then improve multi-shot DWI reconstruction. Approach: A multi-shot, dual density spiral sequence was designed, with each shot having fully sampled k-space center and undersampled periphery. The center of all shots and all coils are concatenated and fed into ESPIRiT to estimate sensitivities. Results: The proposed method successfully estimated shot-to-shot phase variations and yielded comparable results to the reference locally low-rank regularized reconstruction which requires parameter tuning. Impact: The proposed eSNAILS demonstrated the ability of estimating composite sensitivities that incorporate shot-to-shot phase variations. Compared to low-rank modeling methods that assume phase smoothness, eSNAILS can handle cases where there are abrupt phase changes and does not require parameter tuning.
The software system of an MR compatible dedicated brain PET
Authors: Liu Jiamin , Ren Ning , Zeng Tianyi , Kuang Zhonghua , Wang Xiaohui , Liu Zheng , Zheng Hairong , Liang Dong , Yang Yongfeng , Hu Zhanli
Published: November 2024

Motivation: Dedicated brain PET devices can acquire high-quality images while also allowing for simultaneous imaging with MRI equipment. Goal(s): The implemention of software system of a MR compatible brain PET including data acquisition, sinogram generation, imaging reconstructionis presented. Approach: We designed a virtual crystal-based sinogram generation method and implemented OSEM image reconstruction software with various acceleration strategies. Results: The functionality of the software system and the imaging capability of the PET scanner were demonstrated by simultaneous PET and MRI imaging of the human brain. Impact: The sinogram generation method and image reconstruction acceleration strategies developed in this work can also be used for other PET scanners using high DOI resolution depth encoding detectors.
Dose-dependent and dynamic effects of esketamine on neurometabolism: a 7T functional MRI/MRS study
Authors: Boucherie Daphne , Reneman Liesbeth , Hollmann Markus , Immink Rogier , Schrantee Anouk
Published: November 2024

Motivation: An integrated imaging approach using functional magnetic resonance imaging (fMRI) and functional proton magnetic resonance spectroscopy (fMRS) can increase our understanding of the functional response to antidepressant medication like es-ketamine. Goal(s): We aimed to assess the dose- and time-dependent effects of the antidepressant es-ketamine on the functional brain response. Approach: We used an interleaved fMRI and fMRS experiment to assess whole-brain changes in BOLD signal and neurometabolite changes in the anterior cingulate cortex. Results: Es-ketamine increased glutamate levels and the BOLD signal, and decreased aspartate and glucose levels in the first 10-15 minutes following administration, with specific dose-dependent effects. Impact: Our results show both dose- and time-dependent neurometabolic and hemodynamic responses to es-ketamine. Understanding the contribution of these two determinants of the functional response might advance our understanding of the effects of antidepressant medication on the human brain.
Measurement of metabolic changes in response to different types of visual stimulus using functional MRS at 5T
Authors: Liu Yiling , Yang Yanxing , Wei Yu , Chen Hao , Tal Assaf , Zhang Zhiyong
Published: November 2024

Motivation: Many types of visual stimuli were reported effective for visual perception. However, it’s uncertain whether certain types of visual stimuli illicit larger responses. Goal(s): We aim to measure the metabolic changes in response to different types of visual stimuli to observe which types of visual stimuli can excite larger and more consistent responses. Approach: We designed three different types of stimuli sessions ( non-sense images, houses, and faces) for visual stimulation and observed the metabolic changes in the fMRS data at 5T. Results: Preliminary experiments show that compared to non-sense images and “no interesting” houses, faces stimulate larger responses with dynamic increase. Impact: An fMRS study is implemented to measure the dynamic changes in response to different types of visual stimuli. Preliminary experiments indicate that faces stimulate larger responses.