bluuebunny/crossref_metadata_2025 huggingface dataset:
Accelerated single UTE-Dixon for simultaneous short T2*water and fat imaging using a FLORET trajectory
Authors: Van Anh , Weiss Kilian , Feuerriegel Georg , Braun Philipp , Krishnamoorthy Guruprasad , Gersing Alexandra , Pipe James , Karampinos Dimitrios
Published: August 2024

Ultra-short echo time (UTE) imaging enables the depiction of short-T2* tissues and is being increasingly used for the generation of CT-like bone images. UTE imaging has been recently combined with single-echo Dixon processing to enable the separation of water and fat signals from a single echo UTE image, but was primarily previously employed in radial stack-of-stars UTE acquisitions with prolonged scan durations. The present work combines single UTE-Dixon processing with a Fermat looped, orthogonally encoded trajectory (FLORET) to enable accelerated simultaneous short T2* water- and fat-separated imaging at sub-millimeter isotropic resolution. The technique is applied in the ankle.
Acute tumour response to STING activation assessed with multi-parametric MRI
Authors: Roy Upasana , Pedersen Malin , Box Carol , Boult Jessica , Rullan Antonio , Schmohl Michael , Carotta Sebastian , Harrington Kevin , Robinson Simon
Published: August 2024

Whilst cancer immunotherapies have shown marked and durable tumour responses in some patients, the majority derive no benefit. Strategies are being exploited to enhance tumour responses to immuno-oncology agents, including pharmacological activation of the STING pathway to create a more inflamed microenvironment. Multi-parametric MRI revealed a dose-dependent increase in murine tumour ADC in response to a STING agonist that was associated with histologically confirmed increase in tumour cell death. An acute, transient increase in tumour R2*, consistent with vascular occlusion, was also found. ADC is a sensitive early imaging biomarker of tumour response to STING agonism.
Feasibility of oxygen-enhanced (OE) and intravoxel incoherent motion (IVIM) MRI for detection of HN cancer radiation therapy induced changes
Authors: Palmér Emilia , Brovall Jesper , Jalnefjord Oscar , Petruson Karin , Nordström Fredrik , Karlsson Anna , Ljungberg Maria , Sohlin Maja
Published: August 2024

Tumor oxygenation is a biomarker proposed as a predictor of radiation therapy (RT) response. Here, the feasibility of Oxygen-Enhanced MRI, intravoxel incoherent motion, and diffusion kurtosis imaging for monitoring of oxygenation changes in head and neck cancers was evaluated. Seven patients were examined pre- and mid-RT. No relative change in population mean longitudinal relaxation rate was observed following RT. A general increase was noticed in population mean diffusion and capillary perfusion fraction, and a decrease in population mean kurtosis. The implementation of these techniques was clinically feasible, and relative changes in almost every derived biomarker could be observed following RT.
Repeatability and reproducibility of a multi-vendor spin and gradient echo (SAGE) pulse sequence for dynamic susceptibility contrast MRI
Authors: Choudhary Poonam , Zhou YuXiang , Ragunathan Sudarshan , Mathew Ethan , Anil Aliya , Semmineh Natenael , Gutierrez Belinda , Karis John , Hu Leland , Schmainda Kathleen , Stokes Ashley , Quarles C.
Published: August 2024

Single-echo pulse sequences are commonly employed for DSC-MRI. The multi-echo spin and gradient echo (SAGE) sequence can be useful in multi-contrast and multi-scale imaging of morphologic and functional features of brain tumor vasculature. The goal of this study is to establish harmonized SAGE sequence and analysis protocol across primary MRI vendors to facilitate multi-site clinical trials. In this work, we present initial results of SAGE sequence multi-site reproducibility and repeatability in phantom, healthy volunteers and high-grade glioma patients.
Diffusion tensor imaging on a 1.5T MR-Linac and comparison to a 3T diagnostic scanner in glioma patients
Authors: Lawrence Liam , Chan Rachel , Stewart James , Ruschin Mark , Theriault Aimee , Myrehaug Sten , Detsky Jay , Maralani Pejman , Tseng Chia-Lin , Soliman Hany , Lim-Fat Mary Jane , Das Sunit , Stanisz Greg , Sahgal Arjun , Lau Angus
Published: August 2024

Diffusion tensor imaging was implemented on a 1.5T MR-Linac and used to scan ten glioma patients and four healthy volunteers. Mean diffusivity and fractional anisotropy (FA) measurements were compared to those at 3T in 35 glioma patients. FA values surrounding the tumour and in white matter structures (genu, splenium, and body of corpus callosum) were investigated for the detection of tumour infiltration and radiation-induced damage, respectively. There was no evidence of dose-dependent white matter changes, in contrast to previous literature. Peritumoural FA changes occurred more frequently for high-grade compared to low-grade gliomas.
Developing a Graph Convolutional Network of Differentiable Graph Module for Multi-Modal MRI Data: An Application to Parkinson's Disease
Authors: Li Fanshi , Li Jun , Guo Yifan , Wang Zhihui , Zhang Zhilin , Liu Xin , Zheng Hairong , Zhu Yanjie , Dong Liang , Wang Haifeng
Published: August 2024

With the ageing of the population, Parkinson's disease (PD) has presented a severe challenge to public health. Here, a deep-learning framework named the AMDGM model was proposed to predict PD patients at an early stage. Firstly, multi-modal image-based models were respectively generated using the AMDGM model. Then, a weighted ensemble network was created as the final model. The proposed method achieved the best AUC performance of 0.872 in the testing cohort, better than others. And the proposed method can predict PD patients early to help clinical radiologists formulate more targeted treatments in the future.
MRFlow: Flow-based neural network for MR image harmonization
Authors: Jeong Hwihun , Kang Dong Un , Kim Jiye , Lee Jongho
Published: August 2024

We propose MRFlow, which is a normalizing flow-based neural network for the MRI harmonization framework. With the normalizing flow trained only with the target domain (e.g., 3T image) data, we harmonize the image from the source domain (e.g., 1.5T image) to the target domain by alternately reducing the norm of the latent variable and increasing similarity between the source domain and harmonized images. When MRFlow is applied to synthesized source domain images, the harmonized images showed lower errors than the source domain images. In the prospective study, the harmonized images became more similar to the target domain images after MRFlow.
High-Resolution Right Ventricular T1, T2, and M0 Mapping Using MR Fingerprinting with a Deep Image Prior Reconstruction
Authors: Hamilton Jesse , Rashid Imran , Rajagopalan Sanjay , Seiberlich Nicole
Published: August 2024

This work proposes a high-resolution (1.2x1.2x5 mm3) MR Fingerprinting method for T1, T2, and M0 mapping of both left and right ventricles during a breathhold, with validation in 12 healthy subjects at 1.5T. A key component is the use of a deep image prior reconstruction for reducing noise and undersampling artifacts despite the decreased SNR when moving to higher resolution. Comparable myocardial relaxation times were measured in both ventricles (LV T1 1061+/-22ms, T2 42.2+/-3.4ms; RV T1 1062+/-29ms, T2 42.7+/-2.5ms). Higher-resolution MRF yielded slightly smaller intersubject standard deviation (SD) but larger intrasubject SD compared to a lower-resolution (1.6x1.6x8 mm3) MRF acquisition.
The performance of evaluation in neoadjuvant chemotherapy for breast cancer on abbreviated breast MRI: comparison with full diagnostic protocol
Authors: Tang Wenjie , Guo Yuan , Chen Siyi , Li Xueli , Xu Yongzhou , Wei Xinhua
Published: August 2024

To compare the diagnostic efficacy of abbreviated breast MRI (AB-MRI) and regular full diagnostic protocol MRI (FDP-MRI) in the assessment of response to neoadjuvant chemotherapy (NAC) in breast cancer, this study retrospectively analyzed the performance of AB-MRI and FDP-MRI in breast cancer patients undergoing NAC. We found that, for experienced radiologists, compared with FDP-MRI, AB-MRI showed similar sensitivity, specificity, and accuracy in the evaluation of pCR and similar accuracy in the measurement of residual tumor size for breast cancer.
Excitation and inhibition in the human M1 during motor memory consolidation and the relation to neural plasticity: a multimodal 7T study
Authors: Eisenstein Tamir , Furman-Haran Edna , Tal Assaf
Published: August 2024

Here, we show, using ultra-high field MRS and functional and structural MRI, how changes in glutamate and GABA in the human motor cortex following motor skill learning may play key roles in promoting motor memory consolidation and neuroplasticity. Increased glutamate after learning was associated with overnight skill performance improvements, and increased functional connectivity of M1 with the striatum, suggesting for functional plasticity. Greater reduction in GABA following learning was associated with increased grey matter volume in M1 overnight, suggesting for structural plasticity. We therefore highlight the importance of these neurochemical modifications in promoting learning and plasticity in the human brain.
Prediction of immune status and overall survival of glioblastoma based on immune-related lncRNA signature and radiomics signature
Authors: Luan Jixin , Zhang Chuanchen , Zhang Di , Ma Guolin
Published: August 2024

In this study, we aimed to investigate the correlation between immune-related lncRNA signature and radiomics signature and immune cell infiltration and immune checkpoint blockade in glioblastoma multiform (GBM), and to develop a prognostic model to predict the overall survival of patients. We found that immune-related lncRNA signature and radiomics signature can better predict the immune status and overall survival of GBM patients, which can help clinical prognosis determination and immunotherapy selection.
Multiparametric MRI radiomic model for diagnosing focal cortical dysplasia and laterality
Authors: Chen Shiqi , Xiao Yawen , Zhang Zhaotao , Dai Jiankun , Gui Yifei , Xiao Xinlan
Published: August 2024

Focal cortical dysplasia (FCD) is the most common epileptogenic developmental malformation which remains challenging to diagnose. This study aimed to investigate the possibility of diagnosing FCD and laterality in epilepsy patients using the multiparametric MRI radiomics model. Radiomic features were extracted from the preoperative MRI images of 86 patients. Multivariable logistic regression was used to develop the diagnosis model. The performance of radiomic model was evaluated with general evaluation metrics and was compared with that of inexperienced radiologists. We concluded that radiomics features derived from the combined of T1WI, T2WI and FLAIR might help diagnosing FCD and laterality.
Radio-pathomic maps of glioblastoma identify phenotypes of non-enhancing infiltration associated with bevacizumab treatment response
Authors: Bobholz Samuel , Hoefs Alisha , Hamburger Jordyn , Lowman Allison , Duenweg Savannah , Winiarz Aleksandra , Stebbins Margaret , Kyereme Fitzgerald , Connelly Jennifer , Coss Dylan , Mueller Wade , Agarwal Mohit , Banerjee Anjishnu , LaViolette Peter
Published: August 2024

We tested the hypothesis that autopsy-based radio-pathomic maps of glioblastoma pathology reveal distinct phenotypes (hypercellular, hypocellular, hybrid, and well-circumscribed fronts) that differ in patient survival and bevacizumab treatment response. Patients with tumor invasion beyond contrast showed worse survival outcomes compared to patients with well-circumscribed tumors. Additionally, patients with hypocellular components of the non-enhancing front selectively benefit from bevacizumab treatment, with an observable reduction in the hypocellular volume over the course of bevacizumab use.
Identification of IDH and tumor subtype of adult-type diffuse gliomas based on WHO CNS5 using standard, high and ultra-high b value DWI
Authors: Wang Xueqin , Shu Xinru , He Pingping , Song Yang , Jiang Rifeng
Published: August 2024

To date, few studies have investigated the association between ADC values and tumor subtypes of adult-type diffuse gliomas based on WHO CNS5. By comparing standard, high and ultra-high b value DWI, our research found that all ADC values can differentiate IDH genotypes with ADC8,000 having the highest AUC of 0.827, and mostly ADC values can differentiate the tumor subtypes of gliomas, with ADC8,000 and ADC4,000 having the highest AUC of 0.780 and 0.902, respectively. High and ultra-high b value DWI, is a potent approach in identifying IDH genotype and tumor subtype of adult-type diffuse gliomas based on WHO CNS5.
Dependency of Proton MR Spectroscopy Neuro-Metabolite Concentrations on Grey Matter Fraction and Location in the Healthy Human Brain
Authors: Gonçalves Ana Jorge , Matthews Julian , Haroon Hamied , Parkes Laura , Asselin Marie-Claude , Williams Stephen
Published: August 2024

Variations in six neuro-metabolite (N-acetylaspartate, creatine, myo-inositol, glutamate, glutamine and glycerophosphorylcholine) signals from MR spectroscopy (MRS) data across eleven brain regions were tested for regional differences and for dependence on the spectroscopic volume tissue composition (fractional grey matter (GM)), using a linear mixed-effect model. We found significant positive correlations of N-acetylaspartate, creatine and glutamate concentrations with fractional GM across all eleven regions and a significant regional effect for all six metabolites. This provides clear evidence that brain metabolite measurements are dependent on both the region and fractional GM, demonstrating the importance of knowing tissue fractions when interpreting MRS measurements.
On-site construction of a point-of-care low-field MRI system in Africa
Authors: Obungoloch Johnes , Muhumuza Ivan , Teeuwisse Wouter , Harper Joshua , van Gijzen Martin , Schiff Steven , Webb Andrew , O'Reilly Thomas
Published: August 2024

Point-of-care (POC) low-field MRI systems have a large potential to increase the accessibility and sustainability of MRI in low- and middle-income countries (LMICs). An important step in translating scientific developments from high-income countries to LMICs is technology that can be assembled or constructed locally. We describe the construction and testing of a POC system on site in Africa. All components to assemble a 50 mT Halbach magnet based system, together with the necessary tools, were air-freighted from The Netherlands to Uganda. With four instructors and six untrained personnel, the complete project from delivery to first image took approximately 11 days.
Artifact reduction for real-time spiral MRI using out-in sampling at 0.55T
Authors: Wong Jeffery , Kumar Prakash , Nayak Krishna , Tian Ye
Published: August 2024

We demonstrate reduced artifacts for real-time MRI of speech production at 0.55T with a gradient echo sequence using spiral out-in sampling, and constrained image reconstruction. This approach avoids banding artifacts experienced by spiral bSSFP sequences, and exhibits reduced blurring artifact compared to a spiral out gradient echo sequence at the same readout duration.
Multi-Coil Multi-Contrast Random Matrix Theory-Based Denoising for Liver Fat and R2* Quantification at 0.55T
Authors: Shih Shu-Fu , Zhang Zhaohuan , Tasdelen Bilal , Yagiz Ecrin , Cui Sophia , Zhong Xiaodong , Nayak Krishna , Wu Holden
Published: August 2024

Liver fat and R2* quantification has been extensively validated at 1.5T and 3T. Recently, there is renewed interest in lower-field MRI because of potential advantages such as a larger bore and lower costs. However, it is challenging to acquire images with sufficient signal-to-noise ratio for accurate fat and R2* quantification at 0.55T. Previous random matrix theory (RMT)-based approaches leverage Gaussian noise characteristics to markedly reduce the noise without compromising the tissue signal. In this work, we investigated a multi-coil multi-contrast RMT-based denoising approach which is compatible with parallel imaging and we demonstrated improved liver fat and R2* quantification at 0.55T.
Characterize right ventricle deformation pattern in pulmonary arterial hypertension using layer-specific strain cardiovascular MRI
Authors: Li Wen , Zhang Xianchang , An Jing , Wetzl Jens , Gu Qing , He Jianguo
Published: August 2024

This is the first study to describe the distribution pattern of right ventricular layer-specific strain/strain rate in pulmonary arterial hypertension patients by processing cine cardiovascular MR images using a deformation registration algorithm based strain analysis software.
Diagnostic pearls and potential pitfalls of free-breathing motion-corrected LGE: a prospective head-to-head comparative study
Authors: Zhou Hui , Luo Jing , Zhang Huiting , Bi Xiaoming
Published: August 2024

This study investigated the advantages and potential disadvantages of the MOCO-LGE sequence. The results showed that MOCO-LGE can effectively improve the image quality compared to BH-LGE. Meanwhile, the MOCO-LGE images could overestimate epicardial hyperenhancement and pericardial effusion, which might lead to overdiagnosis of myocarditis in clinical work. The study indicates that further refinement of this useful sequence may be needed.
DeepFittingNet: a deep neural network-based approach for simplifying cardiac T1 and T2 estimation with improved robustness
Authors: Guo Rui , Si Dongyue , Fan Yingwei , Zhang Haina , Ding Haiying , Tang Xiaoying
Published: August 2024

The most used curve-fitting method for map reconstruction of the cardiovascular magnetic resonance mapping is sensitive to the initial conditions, time-consuming, and prone to fitting error. In this study, we sought to develop a deep-learning approach (DeepFittingNet) to perform T1 and T2 calculations for the most clinically used cardiac parametric mappings, to simplify the clinical workflow of cardiac T1/T2 measurements and improve the robustness. In testing, DeepFittingNet could perform T1/T2 estimation tasks for MOLLI, SASHA, and T2-prep bSSFP. Compared to the curve-fitting algorithm, DeepFittingNet could improve the robustness for inversion-recovery T1 estimation and have comparable accuracy and precision.
Temperature Mapping Based on Chemical Exchange Saturation Transfer of Creatine
Authors: Cai Siqi , Zhou Yang , Zou Chao , Jiang Linhai , Wan Qian , Jiang Chunxiang , Tie Changjun , Zhang Lijuan
Published: August 2024

Chemical exchange between endogenous labile guanidinium (Guan) protons of creatine and free water and its thermal dependency were investigated with CEST imaging. The apparent offsets of Cr-CEST were linearly correlated to the experiment temperatures and was relatively insensitive to Cr concentration and pH variations at a range corresponding to physiological and pathological conditions, suggesting a potential utility of Cr-CEST for in vivo thermometry based on endogeneous creatine of the biological tissue.
3D MR Fingerprinting with Fat-navigator-based Motion Correction for Pediatric Imaging
Authors: Hu Siyuan , Chen Yong , Griswold Mark , Ma Dan
Published: August 2024

MR Fingerprinting (MRF) simultaneously measures multiple tissue properties within a single scan. Although 2D MRF has been shown to be less sensitivie to motion than conventional imaging, bulk motion is still problematic for longer 3D MR Fingerprinting scans. We propose to integrate 3D fat navigators with 3D MRF acquisitions for motion correction in neuroimaging, especially for non-sedated pediatric imaging. The proposed method was validated in in vivo scans of healthy subjects with various types of motions and in non-sedated infants. We showed that the fat-navigated 3D MRF framework could resolve and correct bulk motions of both healthy volunteers and infants.
DEveloping Blood-Brain barrier arterial spin labeling as a non-Invasive Early biomarker (DEBBIE)
Authors: Padrela Beatriz , Tee Mervin , Sneve Markus , Mahroo Amnah , Geier Oliver , Thomas David , Morgan Catherine , Moyaert Paulien , Ozturk Esin , Nordhøy Wibeke , Pålhaugen Lene , Linn Jennifer , Selnes Per , Eickel Klaus , Konstandin Simon , Kuijer Joost , Hoinkiss Daniel , Breutigam Nora , Buck Mareike , Achten Rik , Barkhof Frederik , Hilal Saima , Fladby Tormod , Anazodo Udunna , Petr Jan , Mutsaerts Henk , Günther Matthias
Published: August 2024

One of the earliest signs of Alzheimer’s disease (AD) is the loss of blood-brain barrier (BBB) integrity. Arterial spin labeling (ASL) MRI is a non-invasive way to measure perfusion and several other hemodynamic and physiological parameters, including vascular permeability. The DEveloping BBB-ASL as non-Invasive Early biomarker (DEBBIE) consortium aims to develop and integrate innovative techniques to allow robust BBB permeability assessments by ASL to develop a sensitive, non-invasive, and early biomarker for AD and related dementias. This work summarizes our planned efforts to develop and establish an MRI-based BBB permeability biomarker.
Velocity-selective arterial spin labelling bolus duration measurements: Implications for consensus recommendations
Authors: Driver Ian , Chandler Hannah , Patitucci Eleonora , Wise Richard , Germuska Michael
Published: August 2024

Velocity-selective ASL (VSASL) measurement of CBF is relatively insensitive to arterial arrival times, unlike other ASL techniques, making it suitable for measuring CBF in patient groups with long arrival times. However, VSASL can underestimate CBF when the trailing edge of the labelled bolus arrives before imaging. Our study finds substantial spatial heterogeneity in bolus duration in Fourier Transform velocity-selective inversion (FT-VSI), with short bolus durations in anterior regions and longer bolus durations in posterior regions. These results build on a recent VSASL consensus paper contributing to recommendations for cerebrovascular reactivity mapping experiments.
Reproducibility of the bSTAR sequence and open-source implementation
Authors: Lee Nam , Bauman Grzegorz , Bieri Oliver , Nayak Krishna
Published: August 2024

The reproducibility of scientific reports is crucial to advancing human knowledge. This abstract is a response to the 2023 ISMRM Challenge “Repeat it With Me: Reproducibility Team Challenge”. We reproduce the bSTAR sequence, a very short-TR, 3D half-radial dual-echo bSSFP sequence, providing banding-artifact free images within a large FOV. bSTAR imaging is attractive for various applications at low field and especially attractive for lung parenchyma imaging due to the prolonged T2’. We have successfully reproduced the bSTAR method, and figures with comparable image quality compared to published literature. We provide an open-source implementation using Pulseq and BART.
Coupling between low-frequency hemodynamic oscillations and cerebrospinal fluid flow is altered in patients with cerebral amyloid angiopathy
Authors: Hirschler Lydiane , Zotin Maria Clara Zanon , Lewis Laura , Horn Mitchell , Gurol M. Edip , Viswanathan Anand , Polimeni Jonathan , van Osch Matthias , van Veluw Susanne , Greenberg Steven
Published: August 2024

Cerebral amyloid angiopathy (CAA) is characterized by the accumulation of amyloid-β in the vessel walls. Prominent manifestations of CAA include enlarged perivascular spaces (ePVS) and lower amyloid-β concentrations in CSF, which may be the result of impaired brain clearance. CAA patients also demonstrate impaired evoked vascular reactivity. Whether vascular dysfunction is associated with impaired fluid movement in the human brain remains unclear. Here we show that BOLD-CSF coupling is reduced in CAA patients compared to elderly controls, which is a first demonstration of a cerebral small vessel disease affecting CSF motion.
MR Fingerprinting with a Deep Image Prior Reconstruction for Combined T1, T2, and M0 Mapping and Multi-Contrast Cine Imaging
Authors: Hamilton Jesse , Cruz Gastao Lima da , Rashid Imran , Rajagopalan Sanjay , Seiberlich Nicole
Published: August 2024

This work introduces a self-supervised deep learning reconstruction for cine Magnetic Resonance Fingerprinting, allowing for simultaneous cardiac phase-resolved T1, T2, and M0 mapping (without motion correction or averaging of data across different phases) and bright-blood and dark-blood cine imaging during a 10-second breathhold, with a temporal resolution (24 phases) comparable to standard cine imaging. Results are presented in simulations using the XCAT phantom and in healthy subjects, where the proposed reconstruction yielded reduced noise, undersampling artifacts, and motion blurring compared to previous low-rank and motion-corrected methods.
Optimization of Magnetic Resonance Fingerprinting with Subspace Reconstruction
Authors: Wang Nan , Cao Xiaozhi , Iyer Siddharth , Liao Congyu , Lee Philiip , Zhang Molin , Setsompop Kawin
Published: August 2024

Cramér-Rao Lower Bound has been used to optimize the acquisition design for MRF, but the effect from undersampling and reconstruction has not been taken into consideration. In this work, we evaluated the estimation error and standard deviation using CRLB optimized acquisition parameters with spiral undersampling trajectory and subspace reconstruction. The results demonstrated that CRLB produced lower estimation variation but is sensitive to the selected number of subspaces. A rank that is too low or two high an increase the estimation error. The dictionary match on coefficient maps provided lower estimation error and variation compared to match on whole time series.
Can 3D APTw Imaging improve the differential diagnosis ability of traditional MRI in Ovarian Cystadenoma and Cystadenocarcinoma？
Authors: Yu Yibei , Song Xiaolei , Wang Lixue , Zheng Dandan , Zheng Zhuozhao
Published: August 2024

The therapies for ovarian cystadenoma and cystadenocarcinoma are different, thus the differential diagnosis of ovarian lesions is critical. The diagnostic efficacy increased with the use of DWI and DCE-MRI, but the differential diagnosis of cystic ovarian lesions is still a challenge. This study evaluates the diagnostic efficacy of 3D APTw MRI in the differentiation between cystadenoma and cystadenocarcinoma based on the analysis of the cystic regions. The results showed that APTw SIs had better diagnostic performance than ADC values and may be used as a noninvasive tool for differential diagnosis and therapy guidance.
A deep learning pipeline using priori knowledge for automatic evaluation of placenta accreta spectrum disorders with MRI
Authors: Wang Haijie , Wang Yida , Wang Chenglong , Zhang He , Zhu Hao , Lu Yuanyuan , Song Yang , Yang Guang
Published: August 2024

Placenta accreta spectrum (PAS) is a pathologic condition of placentation associated with significant maternal morbidity and mortality. We enrolled 540 patients from two institutions to build an automatic pipeline for early diagnosis of PAS based on T2W images. An nnU-Net model was trained for automatic segmentation of the placenta, then an image stripe was created, in which utero-placental borderline (UPB) was straightened and centered. The UPB image was fed into a DenseNet-based network together with placental position for PAS diagnosis. The pipeline achieved good performance with AUCs of 0.860 and 0.897 in internal and external test cohorts, respectively.
Affinity of Structural White Matter Tracts between Infant and Adult Pigs
Authors: Sun Wenwu , Ahmed Ishfaque , Dubrof Stephanie , West Franklin , Park Hea , Zhao Qun
Published: August 2024

Affinity of structural white matter tracts during development is critical for longitudinal studies of many neurological diseases and brain injuries. Diffusion weighted imaging (DWI) data was collected from 3-week-old piglets. Data-driven tractography analysis was applied to profile white matter tracts for the piglets, which were then compared to recently reported 27 adult pig white matter tracts. Among the 27 tracts, 17 were found with consistent high spatial correlations between infant and adult pigs. This result provides possibilities to further study white matter during development, and to evaluate how different interventions (e.g., TBI) alter the brain myelination trajectory.
Exploring whether differences in brain diffusion MRI metrics distinguish symptom phenotypes in athletes exposed to repetitive head impacts.
Authors: McGeown Joshua , Tayebi Maryam , McDonald Matthew , Condron Paul , Holdsworth Samantha , Potter Leigh , Taylor Davidson , McHugh Patrick , Qiao Miao , Maller Jerome , Fernandez Justin , Shim Vickie , Pedersen Mangor , Kwon Eryn
Published: August 2024

It is important to account for the heterogeneity of clinical presentation when studying mild traumatic brain injury (mTBI) with advanced brain imaging. We used post-season symptom data from a cohort of rugby players exposed to repetitive head impacts, and we applied unsupervised learning to cluster athletes into clinically distinct groups. We explored whether these clusters demonstrated post-season group differences in white matter tracts compared to controls. This analysis framework suggests that group differences of diffusion metrics in athletes exposed to repetitive head impacts may be associated with clinical presentation rather than generalisable across all participants.
Quantitative Susceptibility Mapping in Patients with Persistent-Post Concussion Symptoms
Authors: Bell Tiffany , Ansari Muhammad , Mercier Leah , Gobbi David , Frayne Richard , Debert Chantel , Harris Ashley
Published: August 2024

Twenty percent of people experience symptoms months to years following a concussion, known as persistent post concussive symptoms (PPCS). We used quantitative susceptibility mapping (QSM) to measure tissue susceptibility in white matter tracts of patients with PPCS. We provide preliminary evidence for alterations in white matter susceptibility in patients with PPCS and show that susceptibility levels are correlated with symptom severity. We hypothesise altered susceptibility is related to gliosis, resulting in sustained inflammation. Further, this study demonstrates the potential application of QSM to provide novel information on the pathophysiology of PPCS.
Pseudo resting-state by task-evoked functional connectivity.
Authors: Giubergia Alice , Mascheretti Sara , Lampis Valentina , Ciceri Tommaso , Villa Martina , Andreola Chiara , Arrigoni Filippo , Peruzzo Denis
Published: August 2024

Functional connectomics investigates how brain regions are functionally associated. Studies in literature seek to infer a “pseudo-resting” state from task data, however it should be tested whether resting-state-like connectivity can be inferred by task-fMRI data. This work investigates several preprocessings of task-evoked connectivity performing classification experiments, to test their ability to reproduce a real “resting-state” connectivity and their impact on a clinical context, namely the comparison of Typical Readers and Developmental Dyslexics. Our results suggest that a task-free “pseudo-resting” connectivity cannot be inferred from task-fMRI data and that signal preprocessing does not influence the way the classification rules are inferred.
Biophysical deformation in brain-around-tumor on MRI can distinguish radionecrosis vs recurrent tumor in brain metastases: A feasibility study
Authors: Um Hyemin , Hill Virginia , Ismail Marwa , Puri Sushant , Nayate Ameya , Prasanna Prateek , Rogers Lisa , Yu Jennifer , Tiwari Pallavi
Published: August 2024

A significant challenge in the management of metastatic brain tumors following radiation therapy is distinguishing radiation necrosis from tumor recurrence. Differential diagnosis is difficult on routine MRI and patients are subject to invasive procedures to confirm the absence of disease. We explored the feasibility of deformation features from the normal parenchyma to identify disease recurrence versus radiation effects. Our results suggest that measurements of the subtle tissue deformations in the normal-appearing brain regions may elucidate differences in the tissue microarchitecture of radionecrosis and tumor recurrence and may serve as surrogate markers to non-invasively characterize treatment response in brain metastases.
Functional Activation Pattern to varied working memory loads in Mild Traumatic Brain Injury Patients
Authors: Jiang Li , Zhuo Jiachen , Roys Steven , Rhodes Chandler , Raghavan Prashant Raghavan , Gullapalli Rao
Published: August 2024

Mild traumatic brain injury (mTBI) account for 85% of all TBIs. Working memory impairment is one of the most common symptoms in mTBI patients and may persist years post-mTBI. In this study, we used N-back fMRI to investigate the varying N-back task loads on the functional activation pattern in patients with mild TBI and age-matched healthy controls (HCs) as well as the longitudinal changes within mTBI group. Our results suggested that appropriate task load would be more sensitive in detecting the subtle brain functional changes, even though differences in behavioral performance between mTBI and HCs were absent.
Simultaneous concentration and T2 mapping of brain metabolites by multi-echo spectroscopic imaging
Authors: Rizzo Rudy , Stamatelatou Angeliki , Heerschap Arend , Scheenen Tom , Kreis Roland
Published: August 2024

A multi-parametric MR Spectroscopic Imaging (MRSI) experiment (Multi-Echo Single-Shot MRSI, MESS-MRSI) deploys partially sampled multi-echo trains from single readouts combined with simultaneous multi-parametric model fitting to produce metabolite-specific T2 and concentration maps in 7min. It was tested in-vivo on a cohort of 5 subjects. Cramer-Rao Lower-Bounds (CRLBs) are used as measure of performance. The novel scheme was compared with the (i) traditional Multi-Echo Multi-Shot (MEMS) method and (ii) a truncated version of MEMS, which mimics the MESS acquisition (MESS-mocked). Results extended former findings for single voxel measurements with improvements in CRLB ranging from 17-45% for concentrations and 10-23% for T2s.
sLASER Performed Similarly to PRESS at Revealing Metabolite-Age Correlations
Authors: Hui Steve , Gong Tao , Zöllner Helge , Hupfeld Kathleen , Gudmundson Aaron , Song Yulu , Murali-Manohar Saipavitra , Davies-Jenkins Christopher , Oeltzschner Georg , Wang Guangbin , Edden Richard
Published: August 2024

Recent MRS community consensus recommended sLASER over PRESS for reduced chemical-shift displacement. There is very little evidence supporting this consensus in terms of ability to reveal in vivo biochemistry. sLASER- and PRESS-localized spectra were collected in gray- and white-matter regions in 102 adult subjects (aged 20-69). sLASER showed slightly higher SNR than PRESS (by 4% on average), but improved SNR and localization did not convert into reduced variance or improved detection of metabolite-age correlations. Between-subject CVs of 13 modeled metabolites were remarkably consistent, and the pattern of metabolite-age correlations was also similar.
Free-Breathing Dynamic Pancreatic MRI Using Stack-of-Stars Radial Sampling Algorithm and Compressed SENSE
Authors: Noda Yoshifumi , Kawai Nobuyuki , Kaga Tetsuro , Kajita Kimihiro , Ueda Yu , Honda Masatoshi , Hyodo Fuminori , Kato Hiroki , Matsuo Masayuki
Published: August 2024

Dynamic contrast-enhanced imaging is an essential examination in pancreatic MRI. However, non-diagnosable image quality due to motion artifacts and inappropriate scan timing for pancreatic phase are common problems. Recently, free-breathing sequence (4D FreeBreathing) has been introduced and it can provide diagnosable image quality even in free-breathing. In this study, we evaluated the feasibility of 4D FreeBreathing in pancreatic MRI. Our results showed that 4D FreeBreathing could provide diagnosable image quality and appropriate pancreatic phase scanning could be achieved in all examinations.
Defining radiation target volumes for glioblastoma from predictions of tumor recurrence with AI and diffusion & metabolic MRI
Authors: Tran Nate , Ellison Jacob , Luks Tracy , Li Yan , Jakary Angela , Adegbite Oluwaseun , Genc Ozan , Liu Bo , Lin Hui , Villanueva-Meyer Javier , Morin Olivier , Braunstein Steve , Butowski Nicholas , Clarke Jennifer , Chang Susan , Lupo Janine
Published: August 2024

Using pre-radiotherapy anatomical, diffusion, and metabolic MRI from 42 patients newly-diagnosed with GBM, we first used Random Forest models to identify voxels that later exhibit either contrast-enhancing or T2 lesion progression. We then applied convolutional encoder-decoder neural networks to pre-radiotherapy imaging to segment subsequent tumor progression and found that the resulting predicted region better covered the actual tumor progression while sparing normal brain compared to the standard uniform 2cm expansion of the anatomical lesion to define the radiation target volume. This shows that multi-parametric MRI with deep learning has the potential to assist in future RT treatment planning.
Spiral Fast Spin Echo MRI with Interleaved Diffusion Sensitization for Simultaneous ADC and T2 Mapping
Authors: Bielak Lars , Hennig Jürgen , Lottner Thomas , Bock Michael
Published: August 2024

A sequence design is presented based on spiral fast spin echo acquisition with interleaved diffusion sensitization for simultaneous ADC and T2 mapping. With spiral readout trajectories only few echoes need to be acquired per (TE,b) pair allowing to accelerate the acquisition significantly. A phantom experiment with single echo per k-space is shown for T2 and ADC mapping. With a model-based reconstruction both parameter maps can be rapidly reconstructed.
3D Fast Spin Echo using Frequency-Modulated RF Pulses for MRI in Highly Inhomogeneous Magnetic Fields
Authors: Kobayashi Naoharu , Garwood Michael
Published: August 2024

3D Fast spin echo (FSE) with frequency-modulated (FM) pulses has been introduced for MRI in highly inhomogeneous fields. B1 dependent phase in FM pulse excitation and refocus was adjusted in the FM-FSE pulse sequence. Refocus flip angles in FM-FSE were determined with prospective extended phase graph (EPG). Proposed flip angle and phase in FM-FSE were validated in EPG simulation and experiments at 3T by introducing a linear inhomogeneous field. Finally, in vivo human brain imaging with T1- and T2-weighting was performed using the proposed 3D FM-FSE sequence.
REACT-QUANT: simultaneous non-contrast-enhanced subclavian MRA and vessel-wall imaging with multi-parametric quantitative mapping
Authors: Yoneyama Masami , Goto Yasuhiro , Nagao Michinobu , Zhang Shuo , Abe Kayoko , Hamatani Yutaka , Kodaira Kazuo , Ogawa Takumi , Kato Mana , Shiina Isao , Stehning Christian , Van Cauteren Marc
Published: August 2024

Clinical imaging procedure for vascular evaluation and tissue characterization often needs separate MR scans. Both scenarios require multiple imaging sequences with different image contrasts, which results in long exam times and image misalignment due to possible motion between the scans that needs to be corrected in post-processing. In this work, the recently proposed REACT (Relaxation-Enhanced Angiography without ContrasT) technique was further developed and combined with multi-echo data acquisitions and Dixon-based chemical-shift-based water-fat separation. Initial results in patients showed great promise in detection and assessment of vascular and vessel wall lesions in one single scan.
Fetal cardiac 3D cine MRI at low field - whole heart slice-to-volume reconstruction from real-time spiral SSFP at 0.55T
Authors: van Amerom Joshua , Tian Ye , Goolaub Datta , Wood John , Detterich Jon , Nayak Krishna , Macgowan Christopher
Published: August 2024

Spiral SSFP of the fetal heart at low-field has the advantage of low artifact and high sampling efficiency, compared to conventional systems. This work demonstrates the feasibility of spiral SSFP on a high-performance 0.55 T scanner to produce high spatiotemporal resolution real-time 2D and motion-corrected slice-to-volume super-resolution reconstructed 3D cine images of the heart and great vessels of the human fetus in utero. Patient comfort is improved with the use of a low-field scanner, while motion-robust slice-to-volume reconstruction allows for free-breathing acquisitions that do not require precise scan plane prescriptions during acquisition.
Free-running 5D whole-heart MRI with ferumoxytol enhancement to evaluate cardiac function in congenital heart disease
Authors: Si-Mohamed Salim , Romanin Ludovica , Falcao Mariana , Yerly Jerome , Tenisch Estelle , Rutz Tobias , De Bourguignon Charles , Schwitter Jurg , Stuber Matthias , Roy Christopher , Prsa Milan
Published: August 2024

Free-running 5D whole-heart imaging (5D CMR) has been proposed as a means of simplifying CMR exams by capturing the entire 3D cardiac anatomy without the need for ECG gating or breath-holds. We demonstrated that 5D CMR with ferumoxytol enhancement enables the evaluation of cardiac function in comparison to ECG gated 2D CINE images in congenital heart disease patients. In addition, it enables evaluation of the cardiac morphology with improved diagnostic quality in ~40% of the cases. This suggests that the free-running approach has the potential for replacing the conventional 2D imaging for evaluation of both cardiac function and morphology.
Diffusion Tensor Imaging and ActiveAx analysis of Post-Mortem Human Cervical Spinal Cord Injury
Authors: Lesack Nikolai , Morris Sarah , Swift-LaPointe Taylor , Yung Andrew , Prevost Valentin , George Shana , Bauman Andrew , Kozlowski Piotr , Samadi Farah , Fournier Caron , Parker Lisa , Dong Kevin , Streijger Femke , Hirsch-Reinshagen Veronica , Wayne Moore G. R. , Kwon Brian , Laule Cornelia
Published: August 2024

7T Diffusion Tensor Imaging (DTI) and ActiveAx analysis techniques were used to probe the microstructural properties of post-mortem human spinal cord injury tissue. A decrease in DTI fractional anisotropy was observed caudal to (below) the injury epicenter for descending tracts and rostral to (above) the injury epicenter for ascending tracts. All cords displayed increased axon diameter in ascending tracts rostral to the injury site, which may be evidence of axonal swelling. A decrease in axon density for the two subjects with the longest injury-to-death interval may indicate the time scale of Wallerian degeneration-induced axonal damage observable using ActiveAx.
Quantitative correlations of propagator metrics with phosphorylated tau and astrogliosis in chronic traumatic encephalopathy
Authors: Gangolli Mihika , Pajevic Sinisa , Hutchinson Elizabeth , Kim Joong Hee , Benjamini Dan , Basser Peter
Published: August 2024

Propagator metrics computed from high spatial resolution diffusion MRI data are correlated with histopathological assessments of phosphorylated tau (p-tau) and astrogliosis in tissue specimen with a diagnosis of Stage III/IV chronic traumatic encephalopathy (CTE). Region of interest based analysis showed significant correlations of p-tau with non-Gaussianity (NG) in deep cortical gray matter and of propagator anisotropy (PA) with astrogliosis in superficial cortical white matter. An unsupervised clustering approach with PA and NG as inputs is then used to segment MR data of tissue specimen into clusters to determine whether propagator metrics can be utilized to detect underlying pathology.
Impact of Online Safety Screening on Outpatient MRI Workflow
Authors: Chu Sheena , Briel Elizabeth , Garrett John , Reeder Scott , Pirasteh Ali
Published: August 2024

MRI safety screening is required for all patients prior to their MRI exam. We aim to determine the impact of online MRI safety screening on delays and post-arrival cancellations. Time-to-image is the time between when the patient is paged in the waiting area and their first image acquisition. Post-arrival cancellations occur when the patient arrives but does not complete their MRI due to an unexpected safety or other issues (e.g., claustrophobia). We conclude that post-arrival cancellations and overall time-to-image decreased as a result of online MRI safety screening. Keywords: Physics & Engineering: Safety, New Devices, MR Value
Vertical MRI systems may offer a safer platform with substantially reduced RF heating in adult and pediatric patients with CIEDs
Authors: Vu Jasmine , Jiang Fuchang , Bhusal Bhumi , Sanpitak Pia , Webster Gregory , Bonmassar Giorgio , Golestanirad Laleh
Published: August 2024

MRI is restricted for patients with cardiac implantable electronic devices (CIEDs)—especially children with epicardial systems—due to potential radiofrequency (RF) heating of the tissue around the lead. Here, we present the first assessment of RF heating of epicardial and endocardial CIEDs with varying lead lengths in a vertical MRI system, where we found up to a 78-fold reduction in the simulated maximum specific absorption rate (SAR) compared to a horizontal coil. Reduction in the maximum 0.1g-averaged SAR in the vertical coil was consistent for leads with various internal wire geometries and electrical lengths.
Temperature Prediction for Bilateral Deep Brain Stimulation Electrodes Undergoing MRI
Authors: Zulkarnain Nur Izzati Huda , Sadeghi-Tarakameh Alireza , Thotland Jeromy , Harel Noam , Eryaman Yigitcan
Published: August 2024

We utilized a previously proposed workflow to predict heating around the contacts of bilateral deep brain stimulation (DBS) electrodes undergoing MRI. Phantom experiments demonstrated a quantitative agreement with the simulated and experimentally measured temperature for different electrode trajectories and excitations.
7 Tesla MRI of the knee joint after anterior cruciate ligament graft reconstruction: safety discussion and image quality study
Authors: Kraff Oliver , Theysohn Jens , Theisejans Jana , Quick Harald
Published: August 2024

This study presents the MR safety discussion for imaging subjects with metallic fixation buttons after reconstruction of the anterior cruciate ligament, which have not been labeled MR conditional at 7T by the implant vendor. In addition, image quality and artifacts are evaluated in a knee imaging protocol consisting of both gradient- and spin echo sequences. Two imaging cases are presented: one with 7T imaging before and after surgery, and another case with comparative imaging between 1.5T and 7T. Artifact sizes from metallic fixation buttons at the femur did not impair the image quality and diagnostic evaluation of the knee joint.
Detecting high temporal laminar-specific responses with line-scanning fMRI in awake mice
Authors: Choi Sangcheon , Xie Zeping , Liu Xiaochen , Zang Bei , Hike David , Liu Andy , Yu Xin
Published: August 2024

The 2D line-scanning fMRI has been used to map laminar BOLD onset and single-vessel vasodynamic changes. Lately, this method has been applied to map ultra-fast T2*-weighted MRI signal changes, directly coupled to the multi-unit activity in anesthetized mice with 5ms TR. Here, we have adjusted the 1D line-scanning fMRI method to test it for awake mice. The current setup enables the detection of evoked BOLD fMRI signals in the visual cortex following 4s (3 Hz, 20ms) light exposure. It provides the proof-of-concept to further examine the ultra-fast MRI signals directly linked to neuronal activity.
Depth Dependent Signal from Human Ocular Dominance Columns with VASO fMRI at 7T
Authors: Akbari Atena , Gati Joseph , Zeman Peter , Liem Brett , Menon Ravi
Published: August 2024

In this study, we measured the monocular and binocular responses of ocular dominance columns across cortical depths in human V1 using vascular-space-occupancy (VASO) fMRI at 7T. BOLD and VASO images were acquired from five participants using the DZNE sequence with an isotropic resolution of 0.8 mm. Our results indicate that VASO better differentiates the monocular responses between adjacent columns compared to GRE BOLD. In addition, the binocular modulation of the monocular neurons in V1 could possibly be revealed with VASO contrast.
Layer-resolved FMRI activation and connectivity of the left inferior frontal cortex during reading
Authors: Sharoh Daniel , Hagoort Peter , Norris David
Published: August 2024

We present results which demonstrate simultaneous bottom-up and top-down connectivity from BA44 to regions hierarchically inferior/superior to it in the context of a reading paradigm. BA44 is critical to a number of cognitive functions in humans, notably language. We also demonstrate that the layer dependent signal is sensitive to stimulus length. This effect is contrary to what would be expected in primary sensory cortices, as increased length relates to decreased input. Hence, we also provide insight to how canonical cortico-cortical circuits can lead to different outcomes depending on the nature of the input and the stage of the processing hierarchy.