bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating blood supply changes in the osteonecrosis of the femoral head using gadobutrol-based steady-state MRA
Authors: Liao Zhenhong , Zhang Xiaoyong
Published: August 2024

Dynamic evaluation of retinacular arteries is essential for understanding blood supply changes occurring in osteonecrosis of the femoral head (ONFH). The steady-state (SS) magnetic resonance angiography (MRA) may be an effective method as our previous study suggested, however its feasibility is yet to be determined. Therefore, this study intends to use gadobutrol-based SS MRA to evaluate the blood supply of ONFH.
Radiomics based on conventional MRI sequences to differentiate inert fibrogenic tumors and invasive fibrogenic tumors of trunk and limbs
Authors: Gao Peng , Zhang Weisheng , Feng Hexin
Published: August 2024

区分不同亚型的纤维化肿瘤仍然具有挑战性，但具有重要的临床意义。本研究的目的是评估基于常规 MRI 序列的影像组学在区分惰性纤维化肿瘤和躯干和四肢浸润性纤维化肿瘤的价值。预测模型基于 T1 图像的逻辑回归在区分惰性纤维瘤和侵袭性纤维瘤方面具有最好的预测效率，对 T1 和 T2 预测模型贡献最大的特征分别是 idn 和最小轴长。病变的大小和深度对判断肿瘤的性质有一定的参考价值。
Hormone-driven CBF and AAT changes across the menstrual cycle
Authors: Wright Melissa , Crofts Andrew , Davies Saajan , Germuska Michael , Steventon Jessica , Murphy Kevin
Published: August 2024

The current study investigated the influence of progesterone and oestrogen on cerebral blood flow (CBF) and arterial arrival time (AAT) across a menstrual cycle and multiple cortical and subcortical regions. 21 healthy female participants were scanned in a Siemens MAGNETOM Prisma 3T scanner and their bloods were taken to measure circulating hormones. Linear models found that while there was no interactive effect with region for either hormone, circulating oestrogen explained a significant portion of CBF value, while progesterone explained a significant portion of AAT value. Recommendations for future research are discussed.
Assessing Ranges of Cerebral Blood Flow Velocity and Vessel Area with Phase Contrast in Children and Adults
Authors: Doyle Eamon , Wiseman Hannah , Torres Isabel , Shah Payal , Wood John , Borzage Matthew
Published: August 2024

Measuring brain blood flow is possible with phase contrast (PC) imaging. We assessed blood flow through and area of internal carotid and vertebral arteries in pediatric and adult populations. Sequences parameters are suggested based upon the findings to facilitate PC acquisitions at other institutions.
Volumetric MRI analysis of occipital gyrus in fetuses with isolated ventriculomegaly
Authors: Zhang Xin , Wu Fan , Chen Zhaoji , Li Yuchao , Liu Zhenqing , Xie Chenxin , Liu Hongsheng
Published: August 2024

The lateral ventricle is closely related to the occipital lobe anatomically. We found changes in cortical volume and white matter volume in isolated fetuses ventriculomegaly. This study will address whether occipital and occipital gyrus volumes differ in IVM and investigate the developmental pattern of the occipital lobe with increasing gestational age investigate. This study will help to provide the research basis for the study the neurodevelopment in IVM fetuses.
MR Vascular Fingerprinting with 3D realistic blood vessel structures and machine learning to assess oxygenation changes in human volunteers
Authors: Delphin Aurélien , Coudert Thomas , Fan Audrey , Moseley Michael , Zaharchuk Greg , Christen Thomas
Published: August 2024

The MR vascular fingerprinting (MRvF) approach extends the concept of MR fingerprinting to the study of microvascular properties and functions. Encouraging results have been obtained in healthy human volunteers as well as in stroke and tumor models in rats. However, it has been suggested that the method has a low sensitivity to blood oxygenation measurements. We improved the MRvF approach by using simulations with 3D realistic blood vessels from animal microscopy, new fingerprint-pattern organization and machine learning tools. The method was tested in retrospective data acquired in healthy-human volunteers while breathing different gas mixtures (Hyperoxia (100%O2), Normoxia (21%O2), hypoxia (14%O2)).
Anatomical priors informed tractography. Evaluation on the DiSCo synthetic dataset
Authors: Durantel Thomas , Coloigner Julie , Caruyer Emmanuel , Girard Gabriel , Commowick Olivier
Published: August 2024

White matter fiber tracking using diffusion magnetic resonance imaging (DWI) provides a powerful approach to map brain connections, but they are not completely reliable both in academic and clinical context. This is because most methods infer global connectivity from local information,leading to a high rate of false positive. We propose a method to include anatomical prior in the tractography algorithm. We show on synthetic DiSCo data that including this prior on two state-of-the-art tractography algorithms could improve the overall shape of the tractograms.
CMRsim - A Python package for MRI simulations incorporating complex organ motion and flow
Authors: Weine Jonathan , McGrath Charles , Kozerke Sebastian
Published: August 2024

We present CMRsim, a new Python package for MR simulations efficiently incorporating complex organ motion and flow. The MR signal can be calculated using both Bloch simulations as well as analytical signal models. The package leverages TensorFlow2 for GPU acceleration and thereby facilitates fast simulations while also providing a compilation-free framework for prototyping and community contributions. Significant effort has been put on maintainability and software engineering best practices. The API reference as well as information on installation and how to get started is publicly available at: https://people.ee.ethz.ch/~jweine/cmrsim/latest/index.html Keywords: Open-source, Simulation, Cardiovascular, Motion, Reproducible science, Digital twin
QMRI-neuropipe: A flexible software framework for the analysis of quantitative MRI data
Authors: Dean Douglas , Adluru Nagesh , Guerrero Jose
Published: August 2024

Quantitative MRI provides a unique opportunity to characterize the underlying tissue and establish measurements that canserve as biomarkers. However, many of these methods require specialized workflows and and tools which limit their broader adoption. Here, we present QMRI-neuropipe, an open-source, flexible framework that provides a wide selection of methods, algorithms, and tools for processing and analyzing multiple qMRI datatypes. QMRI-neuropipe supports the Brain Imaging Datset Standard (BIDS) and currently supports processing of diffusion and relaxometry datasets. Future developments will aim to incorporate alternative quantitative MRI methods (e.g. MT, QSM, etc.) into the QMRI-neuropipe framework.
Novel subject-specific method of visualising group differences from multiple DTI metrics without averaging
Authors: Kwon Eryn , Tayebi Maryam , McGeown Joshua , McDonald Matthew , McHugh Patrick , Condron Paul , Potter Leigh , Taylor Davidson , Maller Jerome , Qiao Miao , Wang Alan , Nielsen Poul , Fernandez Justin , Scadeng Miriam , Holdsworth Samantha , Shim Vickie
Published: August 2024

Averaging is commonly used for data reduction/aggregation to summarise such high-dimensional data, resulting in information loss. However, individual variability makes group-wise comparisons difficult without data reduction/aggregation. To address these issues, we developed a novel technique that integrates diffusion tensor (DTI) metrics along the whole volumes of the fibre bundle using a mesh-fitting technique. Using the right Corticospinal Tract (rCST) as an example, we demonstrate the utility of the method in detecting differences in DTI metrics of contact-sports and non-contact-sports athletes.
Post mortem magnetic resonance imaging simulation system
Authors: Kabasawa Hiroyuki , Kojima Masatoshi , Yajima Daisuke , Makino Yohsuke
Published: August 2024

A MR Image simulation system for post mortem subject scanning is developed and validated. The system has MR console like user interface. It has body temperature input as well as tissue fixation condition input, so that post mortem MR imaging can be simulated for various scanning condition. The system was validated for T1 weighted image and FLAIR for low body temperature condition. The result showed the system could simulate the actual acquired image contrast change associated with body temperature change. The proposed system can be used to predict MR contrast change associated with body temperature as well as fixation condition.
De-streaking effect Deep Learning Reconstruction in free-breathing dynamic contrast enhanced Liver MRI
Authors: Park Eun Joo , Lee Yedaun , Lee Ho Joon , Yi Jisook , Lee Joonsung , Wang Xinzeng , Guidon Arnaud
Published: August 2024

In dynamic contrast enhanced (DCE) liver MRI, fast image acquisition with free breathing comes in expense of artifacts and noise, the most notably streak artifacts. In our study, we evaluated de-streaking effect and image quality of free-breathing stack of star liver MRI acquisition with deep learning reconstruction. Application of deep learning reconstruction (DLR) provides improved image quality by removing streak artifact and noise in liver MR images.
Ultrafast T2 mapping of knee articular cartilage under compression using a radial turbo-spin-echo sequence at 3T - initial results
Authors: Janacova Veronika , Juras Vladimir , Szomolanyi Pavol , Bencikova Diana , Trattnig Siegfried
Published: August 2024

Quantitative T2 maps have been used for more than a decade in musculoskeletal MR research as a tool for cartilage assessment. In this work, we compared T2 mapping of knee cartilage with ultrafast radial turbo-spin-echo sequence to conventional multi-echo spin echo sequence. We used radial turbo-spin-echo T2 maps to track dynamic changes in knee cartilage during compression. Correlation between the two methods was found in multiple cartilage regions. Dynamic change in T2 values was observable on T2 maps during first two minutes of compression. We demonstrated that radial-TSE sequence allows for fast determination of T2 values of the knee cartilage.
Evaluation of whole compartment and regional meniscal T2* values within elite athletes
Authors: Argentieri Erin , Sacher Sara , Tan Ek Tsoon , Gold Garry , Potter Hollis , Majumdar Sharmila , Koff Matthew
Published: August 2024

Results of the current study demonstrate compartment- and region-specific differences in medial and lateral meniscal T2* values. Meniscal T2* values may provide a non-invasive means to assess response of the tissue specific to the loading environment and identify the early onset meniscal degeneration. A better understanding of the early changes in meniscal T2* values may help define the progression of meniscal degeneration, prior to the onset of gross morphologic defects.
Initial sensitivity evaluation of a new 19F nanoformulation at 3 Tesla using a novel human head coil
Authors: Martinez Gary , Xu Zhan , Nevozhay Dmitry , Harlan Collin , Walker Christopher , Michel Keith , King Tyler , Que Emily , Sokolov Konstantin , Bankson James
Published: August 2024

In order to track immune cells loaded with 19F compound, a nanoformulation based on iron-doped perfluoro-15-crown-5-ether, called Fe-PFCE was developed for Fluorine-19 MRI. It’s relaxation time was characterized with a custom designed 8 channel Fluorine transmit/receive head coil on clinical 3Tesla MR scanner. Its relaxation time (T1/T2) was 39ms/7ms as comparing to 894ms/196ms nanoformulation based on original (undoped) perfluoro-15-crown-5-ether, called “PFCE”. The SNR/19F-concentration ratio of 1ml Fe-PFCE nanoformulation measured by bSSFP was found to be 53% stronger than that of PFCE. A good signal profile was yielded within the coil receiving field.
Cortical alterations after very preterm birth and the association with socio-emotional abilities from childhood to early adolescence
Authors: Fischi-Gomez Elda , Siffredi Vanesssa , Liverani Maria Chiara , Borradori-Tolsa Cristina , Leuchter Russia Hà-Vinh , Hüppi Petra
Published: August 2024

This study compared GM concentration and its developmental trajectory in vey preterm (VPT) and full-term (FT) children aged 6 to 14 years. Widespread abnormal GM concentration was found with complicated patterns of increases/decreases of GM concentration across cortical and subcortical regions. Socio-emotional abilities were association with GM concentration in regions known to be involved in such process for both VPTand FT peers. Our findings suggest the trajectory of brain development following VPT birth may be fundamentally distinctive with impact on socio-emotional abilities.
Diagnostic value of adenohypophyseal magnetic resonance imaging features in girls with precocious puberty
Authors: Liu Dong , Liu Weiyin , Qin Yuanyuan , Ding Guojun , Zhu Wenzhen
Published: August 2024

It is difficult to distinguish IPP from CPP in the clinical diagnosis. GnRH stimulation test has long been considered the gold standard for the diagnosis of CPP and evaluation of hypothalamic-pituitary-gonadal axis activation, but it is a high cost and an invasive approach. To simplify examination and dig out an alternative method is necessary. In our study, analysis of clinical data, adenohypophyseal MRI features and laboratory characteristics of PP girls help us better comprehensive PP. A combined model of adenohypophyseal MRI features and clinical characteristics improved the diagnostic efficacy of PP and provided us a non-invasive and reliable diagnostic method.
Prediction of the Prognostic Factors of Breast Cancer Using MRI with a Continuous-Time Random-Walk Diffusion Model
Authors: Chang Huan , Wang Dawei , Li Yuting , Xiang Shaoxin , Xue Ke , Kong Peng , Zeng Qingshi
Published: August 2024

Breast cancer is a heterogeneous tumor, and its treatment is customized determined by the pathologic and tumor molecular features. This study used a continuous-time random-walk (CTRW) diffusion model to characterize prognostic factors status of breast lesions. The parameter β showed significantly differences in ER and PR status and showed significant correlation with ER and PR expression, and the combination of Dm, α, and β produced the best performance in identifying ER and PR status. Our study demonstrated that the CTRW parameters as potential biomarkers were superior to conventional ADC in predicting prognostic factors of breast cancer.
Effect of general anesthesia on cerebral blood flow measured by Arterial Spin Labeling: A retrospective study
Authors: Lindner Thomas , Huhndorf Monika , Eimer Christine , Becher Tobias , Ahmeti Hajrullah , Jansen Olav , Synowtiz Michael , Helle Michael , Ulmer Stephan
Published: August 2024

In this study, we non-invasively evaluated the change in cerebral blood flow (CBF) and correlation with mean arterial pressure (MAP) before and during anesthesia using Arterial Spin Labeling. It could be shown that both CBF and MAP are reduced comparing the awake and anesthesia-induced state in patients.
Age dependent changes of water exchange rate across the blood-brain barrier (BBB) in 115 subjects with age ranging from 8 to 87 years
Authors: Shao Xingfeng , Shou Qinyang , Felix Kimberly , Ojogho Brandon , Jiang Xuejuan , Gold Brian , Herting Megan , Wang Danny JJ
Published: August 2024

We studied age-related BBB water exchange rate (kw) changes in a wide range of age groups with 115 subjects using diffusion prepared pseudo-continuous arterial spin labeling (DP-pCASL). We observed a significant trend of decreasing kw with age (slow when ≤50 years old and fast when >50 years old) and large spread of kw values in subjects >50 years, which may indicate compromised BBB function in some ageing populations. The inverted U-shaped correlations between kw versus age suggest a more complex age dependent changes in hippocampus and PHG regions.
Extracting CBF and ATT from One or Two Post-labeling Delays-based Arterial Spin Labeled Perfusion MRI via Deep Learning
Authors: Li Yiran , Li Xiufeng , Detre John , Wang Ze
Published: August 2024

Cerebral blood flow (CBF) and arterial transit time (ATT) can be quantified through fitting the arterial spin labeling (ASL) perfusion MRI signal acquired at different post-labeling delays (PLDs) into a kinetic model. Acquiring multiple-PLD ASL MRI needs exponentially prolonged total scan time compared to the single-PLD acquisition, making it highly sensitive to motions and impractical for clinical use. We proposed a deep neural network that can reliably estimate ATT and CBF maps from significantly fewer PLD ASL MRI acquisitions without image quality loss.
High temporal resolution dynamic 23Na-MRI in skeletal muscle following exercise
Authors: Neal Mary , Townsend Isobel , Wightman Harry , Thelwall Peter
Published: August 2024

Atypical Na+ regulation following exercise can be indicative of skeletal muscle dysfunction. Dynamic 23Na-MRI of signal recovery following exercise therefore holds potential to provide a sensitive, quantitative, and non-invasive tool for physiological monitoring of disease progression or response to interventions. 23Na-MRI sequences with temporal resolutions ranging from 2-8 minutes were acquired in the lower leg before and repeatedly after strenuous isometric dorsiflexion. Our data characterised sodium dynamics during recovery from exercise, and demonstrated an initial increase in 23Na signal intensity from baseline levels after exercise ceased. These findings may provide additional metrics for monitoring skeletal muscle dysfunction.
Quantitative assessment of longitudinal changes in intervertebral discs
Authors: Muftuler L. Tugan , Bych Brendan , King Jeffrey , Gliedt Jordan
Published: August 2024

Chronic low back pain is usually associated with degeneration of the intervertebral discs, although the disc itself may not be the source of pain. Unfortunately, there are no objective measures of the disc degeneration process. The gold standard relies on visual assessment of MRI scans, which may not capture complex physiological changes in degenerating discs. We used quantitative MRI metrics to study longitudinal changes disc degeneration over a period of 2 years. Although most subjects did not show visible changes in discs, there were significant losses in disc height and some discs also showed a reduction in ADC and T1ρ.
Cortical demyelination in chronic post-traumatic stress disorder: A study of World Trade Center responders
Authors: Zhou Juin , Huang Chuan , Minos Kritikos , Clouston Sean , Horton Megan , Kotov Roman , Lucchini Roberto , Bromet Evelyn , Luft Benjamin
Published: August 2024

World Trade Center (WTC) responders are at mid-life, with 23% presenting with chronic post-traumatic stress disorder (PTSD). Epidemiologic studies suggest that chronic PTSD is associated with psychomotor slowing and physical functional limitations consistent with intracortical neuroinflammation. Prior neuroimaging has suggested that chronic PTSD is associated with glial activation and reduced cortical complexity, as well as neurodegeneration in the hippocampus and anterior cingulate, suggestive of PTSD-induced cortical neuropathology. Hypothesizing that these results might reduce intercortical density, we evaluated intercortical demyelination in WTC responders with chronic PTSD. We used gray-white contrast purported to measure cortical demyelination and, by extension, interneuronal health.
Quantification of myelination in Children with Attention-deficit/hyperactivity Disorder: A Comparative Assessment with Synthetic MRI and DTI
Authors: lin liping , chen Yingqian , Dai Yan , zi yan , zou Mengsha , qian Long , Liu Meina , zhang Hongyu , yang Zhiyun , su Shu
Published: August 2024

Evaluation of myelin content is crucial for attention-deficit/hyperactivity disorder (ADHD) and other neurodevelopmental disorders. Diffusion tensor imaging (DTI) is a usual tool to assess white matter structural change in ADHD but it’s indirectly. Synthetic MRI–based (SyMRI-based) method, as a suitable quantitative technique, can investigate myelin content through quantifying whole-brain myelin volume fraction (MVF) and myelin volume (MYV). We aim to evaluate myelin estimation using SyMRI–based method and compared it with established DTI metrics in ADHD children.
Detection of Capillary Leakage in a Transgenic Mouse Model of Alzheimer’s Disease
Authors: Hua Ning , Minaeva Olga , Moncaster Juliet , Jara Hernan , Goldstein Lee
Published: August 2024

The goal of the project is to explore the possibility of using dynamic contrast-enhanced (DCE)-MRI for detecting subtle blood-brain barrier leakage in a transgenic mouse model of Alzheimer’s disease. The washout slope of Gd concentration was used to assess microvascular integrity. We observed different washout patterns in transgenic relative to control mice. Our findings demonstrated that the washout slope could be used to assess status of blood-brain barrier permeability in AD mice.
TR(acking) individuals down: Exploring the effect of temporal resolution in resting-state fingerprinting
Authors: Cassone Barbara , Saviola Francesca , Tambalo Stefano , Amico Enrico , Van De Ville Dimitri , Jovicich Jorge
Published: August 2024

Brain fingerprints reside in timescale-specific functional connectivity of specific regions. However, the effect of acquisition’s temporal resolution on fingerprinting is unknown. Here, we manipulated repetition time (TR) in resting-state fMRI acquisitions, and observed that subject identifiability was maximized when using fast (TR = 0.5 s) or slow (TR = 3 s) protocols, and decreased with TR = 0.7, 1 or 2 s. Moreover, while high-level association areas gave the highest contribution to individual fingerprinting regardless of TR, low-level sensorimotor areas were mostly involved in discriminating between acquisitions with different TRs.
Neural perspective on observational drawing: A longitudinal resting state functional connectivity study using 7T MRI
Authors: Safai Apoorva , Katz Jeffrey , Bondy Barbara , Deshpande Gopikrishna
Published: August 2024

Observational drawing is representation of observed 3D real-life objects into 2D drawings on paper, which involves engaging complex skills like visual perception, spatial encoding, memory and decision making. This study investigates longitudinal functional connectivity (FC) in art students who underwent a 16-week long drawing course, in comparison to students who took unrelated courses. The art group showed improved drawing skills and demonstrated enhanced FC between DMN and salience network and in cerebellar regions post-art class, in comparison, with healthy non-art students. These findings imply positive changes in brain functioning on learning and practicing art, thereby highlighting its potential therapeutic applications.
Experimental Validation of Deep Learning Based Local SAR Mapping from 3D B1+ and Localizer-like MRIs for 7T pTx Systems
Authors: Gokyar Sayim , Zhao Chenyang , Wang Danny
Published: August 2024

Local SAR related heating is a limiting safety factor at UHF MRI. Since local SAR cannot be measured, it should either be estimated from the global SAR or predicted by using the available data such as B1+ maps and MRIs. Here we proposed to use a multi-channel 3D CNN to utilize different channels for B1+ maps and MRIs simultaneously to improve local SAR prediction. We validated our method on 6 participants and found that maximum SAR values can be predicted with 80% accuracy, and local SAR variation can be predicted over 95% accuracy by using common image similarity metrics.
Extreme Value Theory as a Risk Analysis Tool to Infer Specific Absorption Rate Intersubject Variability Safety Margins
Authors: Tyshchenko Igor , Lévy Simon , Tahayori Bahman , Johnston Leigh
Published: August 2024

Specific absorption rate (SAR) in parallel transmission (pTx) ultra-high field MRI is typically evaluated by performing offline electromagnetic simulations on a generic human model. Conventionally, a safety margin that addresses the issue of intersubject variability is selected by choice of the 99th or higher percentile of the SAR distribution. In this work, we argue that this approach underestimates the risk of exceeding the SAR limit. As an alternative, we propose the use of Extreme Value Theory (EVT) for controlling the probability of extremal events in the form of large SAR deviations.
The dependence of the macrovascular transverse R2’ relaxation and resultant BOLD fMRI signal on vascular position: A simulation study
Authors: Zhong Xiaole , Chen J. Jean
Published: August 2024

The R2’ effect is the foundation of BOLD fMRI contrast. R2’ is disproportionately sensitive to the presence of macrovasculature, which disrupts the homogeneity of the main magnetic field (B0), resulting in BOLD signal intensities that may heavily depend on macrovascular orientation and volume but also on vascular position. We simulate the BOLD signal strength in a voxel containing macrovasculature at various vascular positions within the voxel. This simulation highlights an additional source of variability in the macrovascular contributions to R2’-weighted MRI.
Using BOLD-fMRI to Compute Respiration Volume per Time (RVT) and Respiration Variation (RV) with Convolutional Neural Network (CNN) in Children
Authors: Addeh Abdoljalil , Vega Fernando , Williams Rebecca J. , Golestani Ali , Pike G. Bruce , MacDonald M. Ethan
Published: August 2024

In many fMRI studies, respiratory signals are unavailable or do not have acceptable quality. Consequently, the direct removal of low-frequency respiratory variations from BOLD signals is not possible. This study proposes a one-dimensional CNN model for reconstruction of two respiratory measures including RV and RVT. Results show that a CNN can capture informative features from the BOLD signals and reconstruct accurate RV and RVT timeseries. It is expected that application of the proposed method will lower the cost of fMRI studies, reduce complexity, and decrease the burden on participants because they will not be required to wear a respiratory bellows
Representation learning of resting state functional MRI using a volumetric variational autoencoder model (3D VAE)
Authors: Peltier Scott , Karker Michelle , Han Kuan , Noll Doug , Liu Zhongming
Published: August 2024

In this work, we consider whether a VAE model trained with volumetric fMRI data (rather than a cortical subset of the data) is capable of encoding fMRI into low-dimensional representations, decoding these representations back into volumetric fMRI space, and also generating new fMRI patterns from the latent space. For 3D VAE model training, validation, and testing, volumetric resting-state fMRI data was used from the Human Connectome Project minimally preprocessed pipeline. We find the 3D VAE is able to accurately represent the spatial and temporal information in the data. In addition, it is able to synthesize realistic resting-state networks.
When BOLD Optimized ME-EPI Echo Combination Isn't BOLD Optimized
Authors: Waggoner R. Allen , Suzuki Chisato , Ueno Ken-ichi , Tanaka Keiji
Published: August 2024

In regions suffering from magnetic susceptibility effects, the use of BOLD optimized echo combination for averaging Single-Shot/Multi-Echo EPI data across echos, leads to voxels with improves signal but reduced BOLD sensitivity. The use of Multi-shot/Multi-Echo EPI can suppress the susceptibility effects allowing BOLD optimized echo averaging that retains BOLD sensitivity.
Towards Look-Locker encoding as an arterial spin labeling mechanism: T1/B1+/perfusion mapping with MR Multitasking
Authors: Serry Fardad , Lee Hsu-Lei , Qiu Shihan , Xie Yibin , Han Fei , Han Hui , Christodoulou Anthony
Published: August 2024

We hypothesized that the Look-Locker (LL) effect can label arterial spins without the need for subtraction between different inversion schemes. We developed a multiple-flip-angle, non-selective-inversion MR multitasking brain scan to produce co-registered T1, B1+, and perfusion-weighted maps. Flow-sensitive LL fitting homogenized B1+ maps and produced flow maps combining features of time-of-flight angiography images and PCASL perfusion-weighted images. GM/WM flow ratios were similar to PCASL and the literature range.
Total Generalized Variation (TGV) Constrained Reconstruction Improves Test-retest Reliability of High Resolution 3D pCASL in Children
Authors: Shou Qinyang , Shao Xingfeng , Felix Kimberly , Stollberger Rudolf , Herting Megan , Wang Danny
Published: August 2024

We developed an accelerated multi-delay 3D pCASL scheme with high-resolution (iso-2mm), CAIPI acceleration and TGV reconstruction to achieve a ~9-minute protocol with 5 delays with 8 averages per delay. We tested the feasibility of this protocol on 19 pediatric subjects and found the proposed imaging protocol with TGV constrained reconstruction can improve the test-retest reliability of high-resolution 3D pCASL perfusion imaging in typically developing children compared to a standard segmented acquisition.
A Mathematical Model for Velocity-Selective Arterial Spin Labeling
Authors: Liu Thomas , Wong Eric , Bolar Divya , Chen Conan , Barnes Ryan
Published: August 2024

A mathematical model is presented that describes the arterial delivery function and cerebral blood volume components in velocity-selective arterial spin labeling. The model incorporates physiologically valid approximations of changes in acceleration and velocity along the vascular system. Applications of the model are shown using a set of example labeling and saturation profiles.
The choroid plexus as a source for selecting an arterial input function for resting cerebral perfusion measures
Authors: Sobczyk Olivia , Sayin Ece Su , Poublanc Julien , Levine Harrison , Duffin James , Fisher Joseph , Mikulis David
Published: August 2024

The choroid plexus is composed of arteries and stroma with negligible metabolic activity allowing its vessels to remain arterialized throughout its structure. We assessed the choroid plexus as a suitable alternate arterial input function rather than the middle cerebral artery in DSC imaging in individuals with both normal vasculature and pathology affecting the middle cerebral artery.
MRI and Ultrasound of lower extremity subcutaneous adipose tissue: potential translational screening tools for lipedema
Authors: Zheng Yinan , Beasley John , Crain Vanessa , Taylor Shannon , Pridmore Michael , Garza Maria , Chen Sheau-Chiann , Aday Aaron , Beckman Joshua , Donahue Paula , Donahue Manus , Crescenzi Rachelle
Published: August 2024

Lipedema is an underdiagnosed connective tissue disorder characterized by disproportionate subcutaneous adipose tissue (SAT) accumulation in the lower extremities. Lipedema is frequently misdiagnosed as obesity and objective diagnostic tools are lacking for lipedema. Patients with lipedema (n=22) and BMI-matched controls (n=7) underwent lower extremity MRI and ultrasound evaluations of SAT as potential diagnostic modalities. MRI and ultrasound measurement of SAT thickness yielded good concordance between modalities (Pearson’s r=0.95, reproducibility coefficient=3.3 mm), and demonstrated similar moderate effect sizes (Cohen’s d>0.5) for discriminating lipedema from controls. MRI and ultrasound are promising screening modalities for lipedema.
Clinical feasibility of synthetic T1-weighted images in evaluation of rotator cuff injury using ZTE-MRI as reference
Authors: Jiang Jingyu , Liu Weiyin , Chen Wen , Sang Ling , Wang Huizheng , Yu Xingyao , Xu Lin
Published: August 2024

Magnetic resonance imaging is the gold standard for evaluation of rotator cuff injury in non-invasive examination. And 90% occur in supraspinatus tendons. In this study, synthetic MRI (SyMRI) generated both structural and functional images to qualitatively and quantitatively evaluate supraspinatus tendon injury using zero-echo magnetic resonance imaging (ZTE-MRI) as structural reference images. Despite superior quality and inter-reader agreement on critical shoulder angle measurements of ZTE-MRI to SyMRI-generated T1WI, SyMRI showed excellent intra-modality agreement of acromion index and CSA to ZTE-MRI and also provided quantitative information for better identifying injured sites at the early stage of rotator cuff injury.
Machine-learning prediction of fMRI language laterality based on morphological features of Arcuate fasciculi CSD tractograms
Authors: Radwan Ahmed , Pretorius Robert , Sunaert Stefan
Published: August 2024

Shape features of the arcuate fasciculi (AF) can be used for predicting language laterality by a machine-learning algorithm as determined by language task-based functional MRI (tb-fMRI) laterality index (LI) relatively accurately (AUC = 0.893, accuracy = 0.868) in a sample of 60 clinical preoperative patients with variable pathology. Constrained spherical deconvolution (CSD) tractograms seemed to give the best outcome of model training regardless of additional streamline filtering or anatomical constraint. The best-performing model appeared to prioritise bundle curl, irregularity and span over the more conventional measures of surface-area and volume.
Macromolecular proton fraction as a biomarker of early myelination: ultrastructural and immunochemical validation in a rabbit model
Authors: Drobyshevsky Alexander , Aksenov Daniil , Yarnykh Vasiliy
Published: August 2024

Ultrastructural and immunochemical methods of myelin quantification were applied to validate a model-based MRI techniques, macromolecular proton fraction mapping (MPF), during early development in major white matter tracts and cerebral cortex in rabbits. MPF trajectories were in general agreement with levels of myelination by histology and accurately reflected differential rate of development between white matter tracts and cortical regions.
Glymphatic Dysfunction Mediates the Influence of White Matter Hyperintensities on Episodic Memory in Cerebral Small Vessel Disease
Authors: Ke Zhihong , Mo Yuting , Xu Yun
Published: August 2024

In this study, we used the diffusion tensor image analysis along the perivascular space (ALPS)-index to evaluate glymphatic function and highlighted the reliability of using the ALPS-index in the early recognition of cognitive impairment (CI) in cerebral small vessel disease (CSVD) patients. We reported that 1) ALPS-index was a sensitive indicator to distinguish mild CI (MCI); 2) ALPS-index was an independent influencing factor of episodic memory in CSVD patients with MCI; 3) ALPS-index mediated the relationship between white matter hyperintensities and episodic memory in CSVD patients with MCI.
Identifying fiber tracts strategic for cognitive impairments in cerebral small vessel disease with harmonized diffusion MRI
Authors: Huang Peiyu , Valentim Carolina Canelas , Biessels Geert-Jan , Chen Christopher , Dewenter Anna , Duering Marco , Hilal Saima , Koek Huiberdina , Kopczak Anna , Lam Bonnie , Leemans Alexander , Mok Vincent , Onkenhout Laurien , van den Brink Hilde , De Luca Alberto
Published: August 2024

Small vessel disease (SVD) is a worldwide leading cause of dementia. Damage to white matter tracts is a key mechanism through which SVD impacts cognition. In this work, we leverage a large multicenter dataset of patients with SVD to investigate which white matter tracts are strategic in SVD, that is, robustly associated with cognitive decline. Our early results show that the corpus callosum, superior longitudinal fasciculus and thalamo parietal tracts were the most associated to processing speed, verbal memory and executive function, respectively. Tract-based measures explained additional variance (2-5%) as compared to whole brain measures.
Tissue damage and impaired processing speed are related to brain parenchyma free water fraction in multiple sclerosis
Authors: Caporale Alessandra , Chiarelli Antonio , Biondetti Emma , Villani Alessandro , Lipp Ilona , Tomassini Valentina , Wise Richard
Published: August 2024

In 99 relapsing-remitting multiple sclerosis (MS) patients and 25 healthy controls we quantified cerebral free water fraction (FWF) and investigated its relationship with lesion burden and information processing speed, measured with Symbol Digit Modalities Test (SDMT). FWF was obtained from the mcDESPOT method, fitting a three-compartment relaxation model to spoiled-gradient-echo and balanced-SSFP signals with varying flip angles. MS patients showed higher FWF than controls, in the lesioned tissue and in normal appearing white matter (NAWM). In NAWM and perilesional tissue, FWF correlated with lesion load. FWF spatial heterogeneity increased with worsening SDMT performance in regions involved in MS-related cognitive impairment.
Time-dependent Diffusion in Acute and Chronic Plaques of Multiple Sclerosis Investigated with Oscillating-gradient Spin-echo.
Authors: Maekawa Tomoko , Hori Masaaki , Murata Katsutoshi , Kamiya Kouhei , Andica Christina , Hagiwara Akifumi , Fujita Shohei , Kamagata Koji , Wada Akihiko , Aoki Shigeki
Published: August 2024

The purpose of our study was to investigate the utility of changes in diffusivity between short and long diffusion time in evaluating acute and chronic plaques of multiple sclerosis. Chronic plaques showed weak diffusion time-dependence with diffusion times between 6.5 ms and 35.2 ms. The differences in diffusion time-dependence were attributed to the internal structure of plaques. DWI with a short diffusion time may provide additional information about the microstructure of MS plaques.
Time- and Signal-Efficient 3T Ultra-High-Resolution Imaging of the Ex Vivo Cerebellum and Entire Human Brain
Authors: Weigel Matthias , Dechent Peter , Galbusera Riccardo , Bahn Erik , Kappos Ludwig , Brück Wolfgang , Stadelmann Christine , Granziera Cristina
Published: August 2024

Ex Vivo MRI of the entire human brain facilitates new and fascinating insights into cerebral and cerebellar morphology and pathology. One key factor for achieving ultra-high spatial resolutions is a signal- and time-efficient MRI sequence, particularly, at 3T field strength. Though counterintuitive at first notion, we suggest a “slow” balanced steady-state free precession (bSSFP) approach with phase-cycling and very low receiver bandwidth (“LoBa-bSSFP”) as a highly signal- and time-efficient scheme for ex vivo acquisitions. LoBa-bSSFP can support spatial resolutions as high as 98-microns isotropic for covering the entire cerebellum on a common 3T MR system.
Altered dynamic effective connectivity of the default mode network in T2DM
Authors: kun xu , jun wang , jing zhang
Published: August 2024

Type 2 diabetes (T2DM) as one of the risk factors for developing Alzheimer's, however, the underlying pathogenesis of cognitive impairment in patients with T2DM was still unknown. our study combined the method of sliding-window approach and Granger causality analysis and found decreased dynamic effective connectivity (DEC) in T2DM compared with healthy people, and the decrease was associated with abnormal blood glucose level.
Association of brain connections in anterior and posterior circulation with the side of asymptomatic internal carotid stenosis and verbal memory
Authors: Chen Jyun-Ru , Lin Chun-Jen , Lee I-Hui , Lu Chia-Feng
Published: August 2024

Previous studies have reported that patients with asymptomatic internal carotid stenosis (aICS) had recall verbal memory impairment. However, the underlying mechanism to elucidate the altered functional connectivity (FC) associated with the anterior and posterior circulation was not proposed. Furthermore, whether the laterality of aICS is a factor in FC alterations and verbal memory impairment requires further investigation. In this study, we reported that the left and right aICS groups showed different patterns of FC changes related to secondary language regions in anterior and posterior circulation. These FCs could be served as imaging biomarkers for recall verbal memory.
A New Method to Improve RF Safety of Implantable Medical Devices using Inductive Coupling at 3.0T MRI
Authors: Park Bu , Guag Joshua , Rajan Sunder , McCright Brent
Published: August 2024

This study describes a new method to improve RF safety of implantable medical devices located outside of the imaging region by using a secondary resonator (SR) to reduce electric fields and corresponding specific absorption rate (SAR) during MRI. The SR is designed to produce opposing electro-magnetic fields (EM-fields) compared to the EM-fields made by a body coil at 3.0T. This study was performed using numerical simulations with ASTM phantom and human models, and corresponding experimental verifications with the ASTM phantom. Keywords: RF safety, secondary resonator
Radiomic feature reliability of protein-based amide proton transfer-weighted images of brain tumors acquired with compressed sensing
Authors: Wu Jingpu , Shen Yiqing , Huang Qianqi , Guo Pengfei , Zhou Jinyuan , Jiang Shanshan
Published: August 2024

Sensitivity encoding (SENSE) is a conventional practice for accelerating APTw image acquisition. To achieve an even higher acceleration, SENSE with compressed sensing (CS-SENSE) was introduced. However, its effect on the radiomic features extracted from the APTw images was yet studied. Here we extracted radiomic features from both SENSE- and CS-SENSE-APTw images and evaluated their reliability in different regions of interest (ROIs). Moreover, filters play an important part in emphasizing specific image characteristics in radiomics. The impact of filters on the radiomic features were also discussed. Our results provided a comprehensive reference for radiomic analyses where CS is implemented for acceleration.
Effects of SMS accelerating factor on stability of radiomics features from quantitative parametric maps of IVIM and DKI in Cervical Cancer
Authors: Shuangquan Ai , Wei Peng , Yaoyao He , Huiting Zhang , Robert Grimm , Zhaoxi Zhang , Lin Peng , Yulin Liu , Zilong Yuan
Published: August 2024

The aim of this study was to explore the effects of SMS on radiomics features in quantitative parametric maps based on IVIM and DKI models. Meanwhile, the effects of whole-tumor and maximal-tumor layer delineation on radiomics features were compared, whether stable features are associated with clinical staging of cervical cancer was analyzed. The results showed that SMS had the greatest effect on features extracted from D* and f map from IVIM model and the least effect on features extracted from ADC map; SMS had a greater effect on the radiomics features extracted by maximum-tumor layer delineation than by whole-tumor delineation.
2.5D Networks for Physics-Guided Deep Learning Reconstruction of 3D Non-Cartesian MRI from Limited Training Data
Authors: Zhang Chi , Piccini Davide , Demirel Omer Burak , Bonanno Gabriele , Moeller Steen , Yaman Burhaneddin , Stuber Matthias , Akçakaya Mehmet
Published: August 2024

Although recent studies enabled physics-guided deep learning (PG-DL) reconstruction of 3D non-Cartesian MRI, it suffers from blurring, partially due to limited training data. In this study we propose 2.5D PG-DL using three 2D CNNs on orthogonal views for 3D reconstruction to efficiently exploit the limited training data. Results on 3D kooshball coronary MRI show the proposed strategy noticeably improves image sharpness.
Posterior Sampling for Accelerated Multicoil MRI Reconstruction using a Conditional Normalizing Flow
Authors: Wen Jeffrey , Ahmad Rizwan , Schniter Philip
Published: August 2024

For accelerated MR image reconstruction, machine learning (ML)-based methods outperform traditional sparsity-based methods by exploiting large datasets to learn effective priors. However, most ML methods output only a single image reconstruction when in fact there may be many plausible reconstructions given the measurement and prior. To extract this diagnostically relevant information, we propose to explore the space of plausible images, i.e., to sample the posterior, using ML. Among ML methods, conditional normalizing flows (CNFs) stand out for rapid sample generation and simple likelihood-based training. In this work, we present the first CNF for posterior sample generation in accelerated multicoil MRI.
Realizing a robust multi-task training strategy with deep learning: application in Spine MR image quality assessment
Authors: Anand Deepa , Shanbhag Dattesh , Bhushan Chitresh , Patil Uday
Published: August 2024

Multi-task training is attractive in AI applications (from memory, processing time and potential data reduction), where tasks have commonality in terms of features, but still requires differentiation for individual outputs derived. In this work we present a methodology to implement robust multi-task learning framework considering various strategies (parallel, iterative and sequential). We tested the approach for image quality assessment of spine MRI localizer images. We demonstrate that the sequential training is the most effective, in preserving an accuracy above the acceptable level while allowing for a save in number of model parameters (50%).
Respiratory Motion Artifact Simulation for DL application in Cardiac MR Image Quality Assessment
Authors: Amirrajab Sina , Khalil Yasmina Al , Pluim Josien , Breeuwer Marcel , Scannell Cian
Published: August 2024

To tackle data scarcity for training a deep-learning algorithm for cardiac MR image quality assessment, we develop a k-space method for simulating respiratory motion artifacts with different levels of severity on artifact-free publicly available cardiac MRI data. The benefit of such simulated data is investigated, demonstrating the usefulness of training a feature extractor with the simulated artifacts for image quality classification. Our proposed method achieved the test accuracy of 0.625 and Cohen's Kappa of 0.473 (n=120 images), ranking third in task one for the CMRxMotion challenge of MICCAI 2022.
Application of MultVane XD combined with compressed sensing in T2-weighted imaging of uterus
Authors: Zhang Haonan , Song Qingwei , Wang Jiazheng , Liu Ailian
Published: August 2024

Through the radial K-space filling, MultiVane XD(MVXD) can significantly reduce magnetic motion artefacts. As the filling percentage increases, artifacts are significantly reduced, but the scanning time gradually increases. The purpose of this study is to investigate the appropriate compressed sensing(CS) acceleration factor(AF) and filling percentage for clinical uterus T2WI.
A two-perfusion IVIM model to account for both villous and trophoblast perfusion in the human placenta
Authors: Maiuro Alessandra , Ercolani Giada , Porpora Maria Grazia , Catalano Carlo , Manganaro Lucia , Capuani Silvia
Published: August 2024

The placenta may incur several pathologies during fetal growth due to perfusion impairment such as Fetal-Growth-Restriction (FGR) and the accretism. Two-perfusion IVIM model (with f1, D1*, f2, D*2 and D parameters) and IVIM model were used to fit data. DWIs were corrected for distributed noise χ. Mean-values differences of the quantified parameters in diseased and healthy placentas were analyzed by ANOVA test. The slower f2 perfusion fraction associated with trophoblastic perfusion was significantly lower in FGR compared to normal placenta, whereas the faster f1, quantifying villi perfusion fraction, was higher in the accretism compared to healthy placenta zone.
Vascular Assessment of Rhesus Macaque Placental Injury through Maternal Intervillous Blood Volume Measurement
Authors: Chen Ruiming , Keding Logan , Vazquez Jessica , Antony Kathleen , Simmons Heather , Johnson Kevin , Stanic Aleksandar , Liu Ruo-Yu , Shah Dinesh , Golos Thaddus , Wieben Oliver
Published: August 2024

Early assessment of utero-placental vasculature is an important novel approach to predicting pregnancy outcomes and fetal growth. Ferumoxytol-enhanced MRI is a powerful tool to measure intervillous fractional blood volume (FBV) in vivo, which could reflect structural and vascular health in the placenta. This study reports such measurements for rhesus macaque placentas that underwent localized Tisseel injections to mimic the effects of local ischemia. We observed increased regions of low FBV with gestation following the Tisseel injection.