bluuebunny/crossref_metadata_2025 huggingface dataset:
Ternary plot method for presenting information acquired by OGSE and PGSE sequences: Evaluation of the peritumoral area in malignant glioma
Authors: Taoka Toshiaki , Ito Rintaro , Nakamichi Rei , Nakane Toshiki , Ichikawa Kazushige , Sakai Mayuko , Ichinose Nobuyasu , Ozaki Masanori , Mori Takaya , Tanaka Yoshiki , Naganawa Shinji
Published: August 2024

The characteristics of tissue structures can be estimated by comparing images with different diffusion times acquired using the OGSE and PGSE methods. However, for multiple images, it is difficult to make pixel-by-pixel comparison. We attempted a method for integrating the pixel values of these images using ternary plotting for malignant glioma cases. Tumor areas with abnormal enhancement, peritumoral abnormal signal areas, and distant edematous areas were evaluated. The ternary plot provided immediate visual information. It also highlighted similarities in the tissue characteristics of the tumor, with enhancement to the peritumoral area showing abnormal signals.
Habitat analysis based on diffusion kurtosis imaging to predict adult-type diffuse gliomas grade
Authors: Wang Peng , Liu Yanhao , Wu Qiong , Wang Shaoyu , Zhang Huapeng , Song Yang , Yan Xu , Gao Yang
Published: August 2024

Glioma composition is complicated, making whole-tumor investigation with traditional pathological analysis typically challenging. It is possible to demonstrate intratumor heterogeneity using habitat analysis in radiography, a technique analogous to biological environmental analysis with individualized descriptions and quantitative expression of subregions inside the region of interest. Therefore, our goal was to create an integrated model for the habitat analysis-based diffusion kurtosis imaging diagnosis of adult-type diffuse glioma grade. According to the findings, diffusion kurtosis imaging based on habitat analysis accurately predicted adult-type diffuse gliomas grade, which may help to resolve some "intermediate situations" that are challenging to diagnose clinically.
Relative CBV Combined with Mean ADC in Assessing the Differential Between Glioblastoma and Primary Cerebral Lymphoma
Authors: Lin Qi , Tang Langlang , Xu Yongzhou , Wu Peng
Published: August 2024

To further evaluate the efficacy of MRI in the differential diagnosis of glioblastoma (GBM) and primary cerebral lymphoma (PCL), this study retrospectively analysed rCBV and mADC-related data from patients with GBM and PCL and performed a quantitative comparison. The rCBV and mADC values were found to be significantly higher in the GBM group than in the PCL group. We diagnosed GBM when rCBV >23.2900 ml/100g or mADC >0.6550×10-3mm2/s, and the corresponding sensitivity, specificity, and predictive values were all high. This demonstrates the important clinical value of the combined application of mADC and rCBV for the definitive diagnosis of brain tumours.
Pre-treatment Turbo Spin-Echo (TSE) intravoxel incoherent motion (IVIM) predicts treatment outcome in nasopharyngeal carcinoma
Authors: Qian Lijuan , Yu Jie , Liu Yuan , Sun Peng , Chen Manman , Li Xin , Yang Fan
Published: August 2024

TSE-DWI-IVIM as a new and feasible method for predicting the early response to Induction Chemotherapy(IC) for NPC patients. Diffusion-related IVIM parameters (pre-D) might be and perfusion-related parameters (pre-f) can be helpful as potential imaging biomarkers of the therapeutic response to IC in NPC patients.
The feasibility of arterial spin labeling imaging of intracranial tumors at 7T
Authors: Ma Xiaoxiao , Cheng Kun , Zhao Chenyang , Qu Jianxun , Li Chenxi , Li Runze , Duan Caohui , Bian Xiangbing , Wang Danny JJ , Lou Xin
Published: August 2024

The goal of this study was to assess the feasibility of pseudo-continuous arterial spin labeling (pCASL) at 7T on patients with intracranial tumors. We found that 7T ASL imaging was feasible and had a higher resolution than 3T ASL imaging and therefore, may enable in vivo assessment of subtle changes and provides a valuable tool for early detection and mechanism investigation of neurovascular function impairments in patients with intracranial tumors.
Differentiation of High-Grade Gliomas from Solitary Brain Metastases in the Peritumoral Edema: using Combined Synthetic MRI and 3D-pCASL
Authors: Ge Xin , Xiong Yuhui , Li Min , Wang Xiaodong , Zhang Jing
Published: August 2024

The main work of our research was to investigate the difference of quantitative MR metrics from synthetic MRI and 3D-pCASL including T1, T2, PD, CBF, and the multiparametric strategies that contained more than one of the metrics between high-grade gliomas (HGGs) from solitary brain metastases (SBMs) in the peritumoral edema. We found that the T1, T2, and CBF were useful metrics for differentiating HGGs from SBMs which were easily confounded with HGGs in daily diagnosis. Furthermore, combining T1, T2, and CBF further improved their diagnostic performance.
Magnetic Resonance Elastography at 0.055 Tesla: A Preliminary Study
Authors: Su Shi , Ding Ye , Hu Jiahao , Lau Vick , Zhao Yujiao , Zhang Junhao , Man Christopher , Leong Alex , Wu Ed
Published: August 2024

Recent development of ultra-low-field (ULF) MRI presents opportunities for low-cost and portable imaging in point-of-care scenarios or/and low- and mid-income countries. Magnetic resonance elastography (MRE) is an essential part of MR abdominal imaging especially for chronic liver diseases. In this study, we explore the MRE at 0.055 Tesla. We demonstrate the feasibility of MRE based on phantom experiments at 0.055 Tesla.
Relaxation Times of the Musculoskeletal Tissues at 0.55 T
Authors: Khodarahmi Iman , Bruno Mary , Brown Ryan , Fritz Jan , Keerthivasan Mahesh
Published: August 2024

Modern 0.55 T MRI promises to increase worldwide healthcare access through lower costs. Knowledge of the tissue relaxation parameters is essential to achieve the desired image contrast. Here for the first time, we quantify the T1 and T2 relaxation times of the musculoskeletal tissues through a Bloch model-based fitting approach. Our results show that the T1 relaxation time of non-fluid tissues is about 47% of those at 1.5 T. T2 relaxation times are about 70% of that of 1.5 T for synovial fluid, bone marrow and subcutaneous fat, and approximately similar to that of 1.5 T for cartilage and muscle.
Low-field MR Multitasking for an integrated abdominal MRgRT imaging framework
Authors: Chen Junzhou , Tian Ye , Lee Namgyun , Cao Mingsong , Yang Wensha , Cui Sophia , Nayak Krishna , Li Debiao , Christodoulou Anthony , Fan Zhaoyang
Published: August 2024

MR applications in radiation therapy has shown great promise for highly conformal treatment. However, MRgRT in the abdomen remains challenging due to motion and the sheer number of organs. In this work, we have demonstrated at 0.55T an integrated multi-task MR platform for adaptive radiation planning and treatment monitoring in the abdomen. We propose using a hybrid GRE-TSE sequence, from a single "pre-beam" scan we are able to generate a volumetric, multi-contrast and motion resolved images for adaptive treatment planning as well as enabling multi-contrast 3D real-time display during treatment.
Simultaneous multi-slice real-time cardiac MRI at 0.55T
Authors: Yagiz Ecrin , Garg Parveen , Nayak Krishna , Tian Ye
Published: August 2024

A standard cine MRI exam typically collects a stack of short-axis slices to cover all left ventricular myocardium and uses electrocardiogram gating and breath-holds. Real-time imaging methods are often used to resolve issues with insufficient gating signal or breath-hold failure. In this work, we demonstrate that real-time SMS cardiac imaging at 0.55T provides sufficient blood-myocardium contrast and regional wall motion evaluation with three-fold acceleration compared to real-time single-band and Cartesian breath-hold ECG-gated cine. We also show an alternative reconstruction approach, clustered locally low rank that can improve image quality.
Multiparametric quantitative MRI mapping using ultrahigh-field strength
Authors: Abbas Zaheer , Zimmermann Markus , Ridder Dominik , Oros-Peusquens Ana-Maria , Shah N. Jon
Published: August 2024

Measurement of quantitative, tissue-specific MR properties such as water content or relaxation times using quantitative-MRI at clinical field strength (1.5T and 3T) is a well-explored topic. Established methods for water content mapping are based on the variable flip-angle (VFA) approach. However, transition to ultrahigh field strength remains challenging due to significantly increased RF field inhomogeneity. Here, we demonstrate a novel VFA method to acquire quantitative water content and relaxation times at 7T with full brain coverage and 1x1x1.5 mm resolution within 7 min. Accuracy and precision of the parametric maps is demonstrated by comparison to already reported results.
Robust reconstruction of electrical conductivity using anatomically-informed quadratic fit
Authors: Savigny Flavy , Lamy Julien , de Sousa Paulo Loureiro
Published: August 2024

Magnetic resonance electrical properties tomography (MREPT), aiming at reconstructing the electrical conductivity and permittivity at radio frequencies. The related reconstruction algorithm relies on the numerical approximation of the Laplacian of the transceiver phase, an operation sensitive to noise. In this work, we evaluate whether 3D parabolic phase fitting combined with anatomical information obtained from T1-weighted and T2-weighted images can be used to improve the reconstruction of conductivity maps of the human brain at 3T.
Preliminary investigation of a rapid proxy measure of T2* in cartilage using a double echo uTE
Authors: Subramanian Aditya , Watkins Lauren , Gold Garry , Kogan Feliks , Barbieri Marco
Published: August 2024

Ultrashort echo time (uTE) T2* mapping of articular cartilage is sensitive to changes in components of cartilage with short T2* such as water bound to proteoglycans and collagen. T2* mapping requires acquiring multiple echoes and fitting the signal intensities to a monoexponential decay model to estimate a single T2*. We propose a ratio based proxy for T2*, the Free Water Index (FWI). Our exploratory study showed high correlations between the index and T2* in vivo, supporting the potential for our index to reduce scan time while retaining information from T2*.
AI-based reconstruction of T2-weighted sequences in prostate MRI: clinical evaluation and impact on diagnostic confidence
Authors: Bischoff Leon , Isaak Alexander , Katemann Christoph , Kravchenko Dmitrij , Mesropyan Narine , Endler Christoph , Wichtmann Barbara , Weber Oliver , Peeters Johannes , Pieper Claus , Kütting Daniel , Sprinkart Alois , Attenberger Ulrike , Luetkens Julian
Published: August 2024

In this prospective study, 56 male patients with suspected prostate cancer were included to evaluate an artificial intelligence (AI) based reconstruction method for T2-weighted sequences in multiparametric MRI (mpMRI). After comparison with conventionally acquired and reconstructed sequences we found the new AI-based method to produce images with higher image sharpness and delineation of lesions, confirmed by both qualitative and quantitative analysis. This is accompanied by a reduction of scan time by 29-37%. Confidence in the assessed PI-RADS scores was significantly higher for the AI-reconstruction. This new technique could therefore potentially increase diagnostic accuracy of mpMRI of the prostate.
Multiparametric MR-based Feature Fusion Radiomics Combined with ADC Maps-based Tumor Proliferative Burden in Distinguishing TNBC vs. non-TNBC
Authors: Liang Fangrong , Zhang Wanli , Li Jiamin , Xu Yongzhou , Zhang Aaron , Jiang Xinqing , Zhen Xin , Yang Ruimeng
Published: August 2024

Triple negative breast cancer (TNBC) is highly heterogeneous, with poorer prognosis, higher recurrence rates and severe treatment challenges. Accurate preoperative identification of TNBC is helpful for individualized patient management. Based on multiparametric magnetic resonance imaging (mMRI), we employed whole-tumor ADC maps-based radiomics (RADC) model, tumor proliferative burden (TPBADC) model, mMRI-based feature fusion radiomics (RFF) model and combinational RFF-TPBADC model to investigate their performance in distinguishing TNBC from non-TNBC. Our results showed that the RFF-TPBADC model outperformed the RADC, TPBADC, and RFF models by integrating mMRI radiomics features and TPBs, demonstrating its potential for classification of breast cancer.
Using convolutional neural network predicts microvascular invasion in hepatocellular carcinoma based on Gd-EOB-DTPA-enhanced MRI
Authors: Liu Baoer , Wang Pingjing , Huang Jianbin , Zhou Wu , Xu Yikai
Published: August 2024

An accurate preoperative assessment of microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) is of great clinical importance in choosing appropriate surgical interventions. We aimed to investigate diagnostic performance of Gd-EOB-DTPA-enhanced MRI for prediction of MVI in HCC using convolutional neural network (CNN). The CNN model based on hepatobiliary phase (HBP) images had great diagnostic efficiency for the prediction of MVI with the AUC of 0.858 (range, 0.854, 0.893). Deep learning with CNN based on Gd-EOB-DTPA-enhanced MRI can be conducive to preoperative prediction of MVI in HCC.
An update of Graded prognostic assessment using molecular markers and Radiomics for estimating survival in NSCLC patients with brain metastases
Authors: He Lan , Liu Zaiyi
Published: August 2024

Rad-molGPA index is prognostic for non-small cell lung cancer patients with brain metastases. The updated Rad-molGPA incorporating radiomics features into the Lung-molGPA is a user-friendly tool to facilitate clinical decision making and appropriate stratification of future clinical trials.
Multi-nuclear 1H and 23Na MRI investigation of fibroadipose tissue sodium in patients with secondary lymphedema
Authors: Taylor Shannon , Pridmore Michael , Garza Maria , Crain Vanessa , Chen Sheau-Chiann , Brown Alaina , Luo Yu , Donahue Paula , Donahue Manus , Crescenzi Rachelle
Published: August 2024

Advanced-stage lymphedema is a disease of chronic fluid accumulation and tissue inflammation that results in fibrosis and subcutaneous fat expansion in affected limbs. Assessment of fat and fibrosis currently relies on biopsies or non-specific bedside measures. Noninvasive MRI could be important for understanding pathophysiology and evaluating emerging therapies. We cross-sectionally evaluated multi-nuclear proton and sodium MRI in patients with lower-extremity secondary lymphedema. Results reveal subcutaneous adipose tissue expansion throughout the affected calf, locoregional fibrosis, and elevated sodium content in fibroadipose tissues particularly in the anterior calf, thereby highlighting the relevance of these technologies for interrogating tissue health in lymphedema.
Habitat Analysis Based on Multiparametric MRI Predicts Lung Adenocarcinoma Subtypes
Authors: Shi Gaofeng , Wang Qi , Feng Hui , Liu Hui , Song Mengyu , Liang Xinyue , Dai Yongming
Published: August 2024

As a promising approach to analyze tumor heterogeneity through image features, habitat analysis has been applied for a variety of tumors, such as lung adenocarcinoma (LUAD). To our knowledge, the previous applications, mainly based on CT and PET images, would potentially hold a limited impact on the power of habitats analysis. In this study, our goal is to extend the applications of habitat analysis in LUAD with multi-parametric MR images, which would be obtained routinely longitudinally and to guide specific therapies.
Deep Learning Reconstruction: Capability for Image Quality and Staging Accuracy Improvements on Chest MRI in NSCLC Patients
Authors: Ohno Yoshiharu , Yamamoto Kaori , Ikedo Masato , Yui Masao , Iwase Akiyoshi , Oshima Yuka , Hamabuchi Nayu , Hanamatsu Satomu , Nagata Hiroyuki , Ueda Takahiro , Ikeda Hirotaka , Yoshikawa Takeshi , Takenaka Daisuke , Ozawa Yoshiyuki , Toyama Hiroshi
Published: August 2024

Deep learning reconstruction (DLR) has been applied in routine clinical practice and started to demonstrate its’ potential in different MR examinations. However, no one have evaluated the utility of DLR for chest MRI, yet. We hypothesize that DLR method is useful for chest MRI and improve image quality and diagnostic performance for T and N factor evaluations in non-small cell lung cancer (NSCLC) patients. The purpose of this study was to determine the influence of DLR method on image quality and diagnostic performance for T and N factor evaluations at chest MRI in NSCLC patients.
Application of fractional order calculus diffusion model in predicting the differentiation in esophageal squamous cell carcinoma
Authors: Zhao Keke , Wang Shaoyu , Zhang Hongkai , Qu Jinrong , Li Hailiang
Published: August 2024

A total of 50 patients with locally advanced ESCC were prospectively enrolled in this study. Diffusion Weighted Imaging (DWI) with multiple high b-values was performed before surgery, and a new set of parameters (D, β and m) from a fractional order calculus (FROC) diffusion model were acquired. The grade of differentiation about ESCC was assessed. We found that β and D value exhibited non-significant difference, and m value showed a significant difference between different grades ESCC (P =0.029).
APTw combined with mDixon‑Quant imaging to distinguish the differentiation degree of cervical squamous carcinoma
Authors: Meng Xing , Liu Ailian , Tian Shifeng
Published: August 2024

APTw and mDixon-Quant imaging were evaluated in this study for discrimination of the differention degree of CSC by histopathology. The APTw and R2* values of the poorly differentiated group were significantly higher than those of the well/moderately differentiated group. And the combination of APTw and R2* values showed a high diagnostic efficacy in discrimination of CSC with different differention degrees.
Cardiac Gated, Ferumoxytol-Enhanced MR Angiography of the Aorta with a Flexible k-space Trajectory: Initial Results
Authors: Finn J Paul , Yoshida Takegawa , Bedayat Arash , Nguyen Kim-Lien , Zhong Xiaodong , Laub Gerhard
Published: August 2024

Contrast enhanced MRA of the aorta is typically performed without cardiac gating, greatly limiting its value in the aortic root and its more widespread utilization. We implemented a cardiac gated sequence for breath-held MRA of the thoracic aorta with flexible contrast during the steady-state distribution of ferumoxytol and compared it to ungated MRA with similar resolution. The resulting images were compared for definition of the aortic annulus, leaflets and ascending aorta. The gated sequence performed significantly better than the ungated sequence for all measured parameters and holds promise as a high quality alternative to gated CTA in appropriate clinical circumstances.
Assessment of Glx and GABA levels in primary dysmenorrhea patients in menstruation and periovulatory phases
Authors: Chen Xue , Huang Zhou , Wu Peng , Li Yonggang
Published: August 2024

The pathogenesis of primary dysmenorrhea (PDM) and the central nervous system (CNS) mechanisms leading to poorer mode and pain sensitization remain totally unclear, which was explored in our study using MEGA-PRESS. PDM patients showed significantly higher Glx level and mildly higher GABA+ level (not significantly) in ACC in menstruation phase. In menstruation phase, the SDS/PCS scores of the PDM patients had a positive correlation with ACC GABA+ levels. The imbalances in ACC GABA+/Glx levels in PDM patients in menstruation phase may be the mechanism mediating depressive symptoms and pain catastrophe.
The effects of repetitive head impact exposure on cerebrovascular reactivity in middle and high-school athletes
Authors: Cohen Alexander , Brett Benjamin , Patel Milan , Ristow Kelly , McCrea Michael , Wang Yang
Published: August 2024

Cerebrovascular reactivity (CVR) can provide a marker of vascular injury. The effects of repetitive head impact exposure (RHIE) during contact sports remains to be fully elucidated. We investigated the effect of sport, time, and their interaction on CVR in contact sport (CS) and non-contact sport (NCS) middle school and high school athletes. There was a significant effect of time and a significant interaction effect between contact group and time on CVR with CVR decreasing pre to post season in the NCS group but remaining unchanged in the CS group.
White Matter Alterations Evident with DTI, DKI and Axonal Radius Measurements in Clinical Presentation of Chronic Symptomatic mTBI
Authors: Abad Nastaren , Bhushan Chitresh , Marinelli Luca , Ajala Afis , Morris H. , Zhu Ante , Fiveland Eric , Lee Seung-Kyun , DeMarco J , Shih Robert , Hood Maureen , Kohls Gail , Kenney Kimbra , Ho Vincent , Foo Thomas
Published: August 2024

Diffusion MRI based microstructural evaluation of DTI, DKI, and intra-axonal radii, enabled by the ultra-high performance MAGNUS gradients, was leveraged in this study to assess differences between healthy controls and chronic mild traumatic brain injury presentations. Parcel-wise group and brain WM asymmetry analysis highlighted specific sub-region involvement differing from healthy controls in evaluated metrics. Subject specific analysis highlighted specific anatomical regions that could be more susceptible in TBI with the effect size potentially masked with central tendency analysis.
IRON OVERLOAD IN AMYOTROPHIC LATERAL SCLEROSIS: DIAGNOSTIC ACCURACY OF VISUAL AND AUTOMATIC ASSESSMENTS
Authors: Contarino Valeria , Russo Francesco Lo , Conte Giorgio , Morelli Claudia , Trogu Francesca , Casale Silvia , Sbaraini Sara , Caschera Luca , Genovese Valentina , Liu Chunlei , Cinnante Claudia , Silani Vincenzo , Triulzi Fabio
Published: August 2024

vVisual SWI-based and automatic QSM-based assessments show high diagnostic accuracy in UMN- predominant ALS
Assessment of Brainstem volume in Myalgic Encephalomyelitis/Chronic fatigue syndrome and long-COVID patients
Authors: THAPALIYA KIRAN , Marshall-Gradisnik Sonya , Barth Markus , Eaton-Fitch Natalie , Barnden Leighton
Published: August 2024

COVID -19 caused by the novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has infected more than 600 million and caused the deaths of over six million people worldwide. The majority of the infected patients do not recover fully from the COVID-19 infections and develop post-COVID conditions also known as long-COVID has similar symptoms compared to Myalgic Encephalomyelitis/Chronic fatigue syndrome. In this study, we evaluated the volumetric changes in the brainstem regions in ME/CFS, long-COVID patients compared to healthy controls. Our study showed that brainstem volumes higher in ME/CFS and long-COVID patients compared to healthy controls.
Changes in the dynamic spontaneous neural activity of brain activity in minimal hepatic encephalopathy
Authors: Lin Jia-Hui , Cao Yun-Bin , Dong Qiu-Yi , Chen Hua-Jun
Published: August 2024

Amplitude of low-frequency fluctuation (ALFF) can identify abnormal regional neural activity in minimal hepatic encephalopathy (MHE). This work sought to evaluate the temporal variability of ALFF to reveal MHE-related alterations in the dynamics of spontaneous neural activity. Healthy controls and patients with cirrhosis [including MHE and without MHE (NHE)] were enrolled in this investigation. Utilizing a sliding-window approach to calculate the dynamic ALFF (dALFF) variability. The dALFF variability in some brain region progressively decreased from NHE to MHE group and it can distinguish NHE and MHE patients. Our findings highlight aberrant dynamic brain function in MHE.
Time-dependent diffusion-weighted imaging for differentiation between glioblastoma and brain metastasis
Authors: Kamimura Kiyohisa , Nakano Tsubasa , Hasegawa Tomohito , Nakajo Masanori , Uchida Hiroyuki , Iwanaga Takashi , Imai Hiroshi , Feiweier Thorsten , Yoshiura Takashi
Published: August 2024

To investigate the utility of time-dependent DWI for differentiating between glioblastoma and brain metastasis, 65 patients with glioblastoma and 27 patients with brain metastasis were examined. ADC was not significantly different between the two tumor types neither at a short (7.1ms) nor at a long (44.5ms) diffusion time, whereas the ADC difference (ΔADCmean, ΔADC5, ΔADC95) and ADC change ratio (rADCmean, rADC5, rADC95) were significantly higher in brain metastasis than in glioblastoma. The ΔADCmean showed the best diagnostic performance. The ΔADCmean and rADCmean showed a significant negative correlation with ADC44.5msmean, but not with extracellular extravascular space volume fraction derived from DCE-MRI.
Healthy and cancerous brain ADC: diffusion- and echo time dependence with pulsed gradient spin-echo (PGSE) diffusion imaging
Authors: Johansson Jens , Lagerstrand Kerstin , Björk-Burtscher Isabella , Laesser Mats , Hebelka Hanna , Maier Stephan
Published: August 2024

Clinical systems vary widely in their gradient performance. Accordingly, effective diffusion time and echo time, which are minimized by the system software according to available gradient performance, can differ significantly among systems. A major concern is that non-Gaussian diffusion in tissues can lead to significant variation of the measured apparent diffusion coefficient (ADC), which would clearly diminish its value as biomarker. This study evaluated if diffusion and/or echo time variations in pulsed gradient spin-echo (PGSE) sequences significantly influences the ADC measured in healthy brain and brain tumors.
Arterial Spin Labeling in Cerebral Gliomas During Breath-Holding
Authors: Solis-Barquero Sergio , Calvo-Imirizaldu Marta , Aramendia-Vidaurreta Veronica , Echeverria-Chasco Rebeca , Martinez-Simon Antonio , Cacho-Asenjo Elena , Vidorreta Marta , Dominguez Pablo , de Eulate Reyes Garcia , Fernandez-Seara Maria
Published: August 2024

PCASL was used to measure cerebral blood flow (CBF) in eighteen patients with high-grade gliomas (III and IV) during normal breathing followed by a breath-holding task (ten periods of 21s interleaved with periods of normal breathing) to assess baseline CBF and cerebrovascular reactivity (CVR). All patients completed the task successfully and CBF and CVR maps were generated. CBF ratio in contrast-enhanced tumor area was higher in grade IV than grade III gliomas, as expected. CVR in tumor areas was decreased compared to GM CVR values. More studies are needed to assess the CVR heterogeneity in tumoral tissue.
Preoperative ASL correlates with molecular markers of IDH and HIF-1α in glioma microenvironment and is predictive of patient outcome
Authors: Geng Ruiwen , Dong Yang , Xie Lizhi
Published: August 2024

This study retrospectively analyzed the association between arterial spin labeling (ASL) and the molecular markers of isocitrate-dehydrogenase (IDH) mutation and hypoxia-inducible factor (HIF) -1α in glioma. The association of patients’ overall survival (OS) and progression-free survival (PFS) with quantization cerebral blood flow (CBF) from ASL, the imaging parameters from conventional MRI, clinical and pathological parameters were investigated in glioma.
Characterising glioma heterogeneity with diffusion-relaxation MRI and InSpect
Authors: Slator Paddy , Simoes Rui , Henriques Rafael , Carvalho Tânia , Alexander Daniel , Shemesh Noam , Ianus Andrada
Published: August 2024

We characterise ex-vivo mouse brain tumours with combined T2-diffusion MRI and InSpect, a data-driven unsupervised learning technique that identifies distinct tissue components. We hence reveal heterogeneous tumour structures without imposing a biophysical model.
A SNR and contrast comparison study at 0.11T, 0.25T, 1.5T and 3T MRI systems
Authors: Qiu Yueqi , Bai Haoran , Chen Hao , Zhang Zhiyong
Published: August 2024

Low-field MRI systems have seen a renaissance recently due to improvements in technology and its low costs. However, properties like SNR, T1 and T2 values of low fields have caused a lot of concern because they always change with field strengths. This study conducted the SNR comparison based on phantom and fitted the quantitative mapping of human brains at 0.11T, 0.25T, 1.5T and 3T to design a set of protocols enabling similar contrasts of the typical clinical images at different fields. The impacts of lowered magnetic field strengths on imaging quality were shown in this study.
An initial exploration of spiral imaging for quantitative fetal T2* mapping on a low-cost low-field MRI scanner
Authors: Verdera Jordina Aviles , Leitao David , West Daniel , Hajnal Joseph , Malik Shaihan , Tomi-Tricot Raphael , Hutter Jana
Published: August 2024

Fetal MRI is an important complementary technique to ultrasound to monitor fetal health. Low-field MRI benefits from reduced distortion, increased B1 homogeneity, wider bore sizes for maintained field homogeneity and longer T2*. The latter is particularly beneficial for single-shot techniques as it allows more flexible and longer read-out strategies. This abstract explores, for the first time, spiral read-out for fetal brain T2* relaxometry and offers preliminary quantitative fetal brain T2* results. Next steps include further exploration of flexible read-out strategies such as undersampled interleaved spirals to work towards higher temporal resolution and motion robustness.
Study of Frequency selective surface (FSS) to shield solenoids for low-field portable MRI
Authors: RAJENDRAN MEENA , HUANG SHAOYING
Published: August 2024

The lightweight frequency selective surface(FSS) using high-pass inductive mesh grids is proposed as shielding of RF solenoids at 2.84MHz for an MRI system using a Halbach array(average B0=67mT). Its effects on the coil B1-sensitivity and the shielding effectiveness are examined. A solenoid(diameter=60mm) was used as an example and the shielding of 5-25mm away was examined. The 5mm-away-FSS-shielded coil has 50.1% (in simulation) and 91.3% (in measurements) higher B1-sensitivity and comparable shielding effectiveness within a defined FoV compared to the copper-shielded coil of the same dimensions. The measured data agree with the simulated ones.
Breast and Chest RF Design and Optimization for Ultra-low Field MRI
Authors: Hornung Torben , Koonjoo Neha , Yan Susu , Rosen Matthew , Bortfeld Thomas
Published: August 2024

MRI guidance in Proton Therapy can improve breast cancer targeting accuracy during treatment planning. This study focuses on RF coil optimization for breast imaging at ultra-low field where proton beam deflection is minimal. Our previous optimization algorithm was further improved to adapt to any breast-shaped coil and any anatomical region. It was also developed for organs-at-risk imaging with a deep view into the chest. This new optimization method was tested for a single-channel conical-shaped coil and validated with imaging. The optimized coil showed a more homogenous B-field compared to its unoptimized evenly spaced wound coil in agreement with the simulations.
Improved T1w Imaging at Ultra-Low Field by use of phase-sensitive reconstruction
Authors: Lafayette Samson Lecurieux , Padormo Francesco , Cawley Paul , Ljunberg Emil , Teixeira Rui , Edwards David , Rutherford Mary , Arichi Tomoki , Hajnal Joseph
Published: August 2024

A phase-sensitive reconstruction is used on adult and neonatal T1w acquisitions on a ultra-low field point-of-care MRI system. We show improved image contrast and reduction in confusing intensities associated with rectification of negative signals.
Characterization of Longitudinal Anatomic and Functional Changes following HIFU Therapy and Implications for Prostate Cancer Surveillance
Authors: Breto Adrian , Algohary Ahmad , Tradewell Michael , Bittencourt Leonardo , Kryvenko Oleksandr , Gonzalgo Mark , Punnen Sanoj , Parekh Dipen , Nahar Bruno , Stoyanova Radka
Published: August 2024

Detecting prostate cancer recurrence after high intensity focused ultrasound (HIFU) therapy is a challenge for clinicians. We characterize longitudinal anatomical/functional changes of prostate in men undergoing HIFU therapy for prostate cancer. Nineteen men had mpMRI exams pre-HIFU, and at 1 and 12 months post-HIFU. Prostate volume decreased by 17% on the one year exam and in two-thirds of men changes in prostatic axis, up to 20 degrees in the direction of ablation. Functional mpMRI analysis shows a dramatic decrease in volume transfer constant (Ktrans) on dynamic contrast enhancing (DCE) imaging while there were no changes in apparent diffusion coefficient (ADC).
Automatic Assessment of UTE MRI High Signal Volume in the Lung for Pediatric Patients with Cystic Fibrosis
Authors: Genkin Daniel , Zanette Brandon , Benkert Thomas , Ratjen Felix , Santyr Giles , Kirby Miranda
Published: August 2024

High signal volume (MR-HSV) obtained by Ultrashort Echo-Time (UTE) MRI has been shown to be associated with disease severity in adults with CF, but has yet to be investigated in pediatric CF patients. In this study, MR-HSV was automatically extracted from UTE MRI of pediatric CF (n=9) and healthy (n=4) participants. MR-HSV measurements were significantly increased in CF compared to health, and increased MR-HSV correlated with decreased lung function (ie. FEV1pp, FEV1/FVC). The findings in this work confirm that MR-HSV measurement is feasible in pediatric participants and may reflect disease severity associated with airway/parenchyma signal intensity abnormalities in CF.
Signal intensity form of extended Tofts model for quantitative analysis of dynamic contrast enhanced MRI data
Authors: Fan Xiaobing , Chatterjee Aritrick , Ren Zhen , Oto Aytekin , Karczmar Gregory
Published: August 2024

The extended Tofts model (ETM) requires calculation of contrast agent concentration in tissue as function of time (C(t)) using a non-linear model that results in error propagation. Here, we introduce a signal intensity (S(t)) form of ETM (SI-ETM) without calculating C(t). QIBA DCE-MRI data was used to validate the SI-ETM, and then human prostate DCE-MRI data were analyzed to compare physiological parameters calculated from the ETM and the SI-ETM. The parameters calculated from S(t) were strongly correlated with the values calculated from C(t). Bland–Altman analysis showed good agreement between the parameters calculated from the ETM and the SI-ETM.
Quantitative analysis of the placental structure and function and fetal growth using intravoxel incoherent motion MRI
Authors: Schonberger Dana , Link-Sourani Daphna , Avisdris Netanell , Rabinowich Aviad , Fadida Bella Specktopr , Ben-Sira Liat , Joskowicz Leo , Hiersch Liran , Zilberman Ayala , Ben Bashat Dafna
Published: August 2024

Placental structural and functional parameters are important for the assessment of placental insufficiency and fetal growth. Here we assessed quantitative measures of placental structural and functional parameters extracted from Intravoxel-incoherent motion (IVIM) with radiomics analysis, in fetuses with growth restriction (FGR) and appropriate for gestational age (AGA). Placental structure (volume and centricity index (CI, umbilical cord insertion location) were correlated with radiomics features of placental perfusion in AGA, and some were found to be significantly different between FGR and AGA, indicating higher functional heterogeneity in FGR. This multi-parametric quantitative placental assessment may improve identification of FGR fetuses.
Correlation of T1/T2/PD map and apparent diffusion coefficient for neoadjuvant therapy response evaluation in three breast cancer subtypes
Authors: Jiang Wenhong , DU Siyao , Xie Lizhi , Zhao Min , Xie Zichuan , Zhang Lina
Published: August 2024

In this study, we evaluated and analyzed the potential correlation of first-order feature pairs from T1/T2/PD and ADC maps within different treatment response groups in locally advanced breast cancer patients undergoing neoadjuvant chemotherapy (NAC). In TNBC subtype, multiple features on ADC and PD maps strongly correlated only in pCR group, which may indicate PD map as complements to ADC for monitoring NAC response.
Concurrent mapping of brain metabolism and airway architecture during respiration and volitional apneas
Authors: Langham Michael , Xu Jing , Wehrli Felix
Published: August 2024

Obstructive sleep apnea is associated with changes in upper airway morphology and sleep disturbances from transient nocturnal hypoxemia and hypoxia. The latter adversely affects brain metabolism and neurologic function. MRI is the only non-invasive modality cable of concurrently visualize airway architecture and quantify neurometabolism during sleep. We present an interleaved pulse sequence and demonstrate its ability to detect metabolic response and airway anatomic alteration from a swallowing apnea (SA). Although airway anatomy during SA is distinctively different from a breath-hold apnea both result in similar physiological responses in terms of cerebral blood flow and venous blood oxygenation.
Quantification of APT and NOE(-3.5) using chemical exchange saturation transfer MRI with double saturation powers (DSP-CEST)
Authors: Zhao Yu , Zu Zhongliang
Published: August 2024

In this study, we proposed a new data-postprocessing method to specifically quantify the APT and NOE effects based on two canonical CEST MRI acquisitions with double saturation powers (DSP). First, Numerical simulations based on Bloch equations is used to demonstrate that the proposed method can detect the APT and NOE effects with a removal of background signals from the direct water saturation (DS) and the semi-solid magnetization transfer (MT) and the CEST signals that originate from the fast-exchange pools. Then, an in vivo validation of the proposed method is conducted using an animal tumor model at a 4.7-T scanner.
Prospective Motion Correction for 3D-EPI fMRI using Orbital Navigators and Linear Regression
Authors: Ulrich Thomas , Riedel Malte , Prüssmann Klaas
Published: August 2024

We propose to apply a navigator-based prospective motion correction method to 3D-EPI fMRI scans. The method is investigated during in-vivo volunteer experiments with and without intentional motion. Post-processing with SPM12 shows that head motion is largely compensated by the navigator method. We show that the technique is sensitive to breathing motion and cardioballistic motion by comparing to physiological measurements from a breathing belt and pulse oximeter, and we show that it strongly reduces inter-volume displacements.
Self-navigated free-breathing ZTE lung imaging
Authors: de Arcos Jose , Solana Ana Beatriz , Weir-McCall Jonathan , Ljungberg Emil , Kaggie Joshua , Wiesinger Florian
Published: August 2024

Here we propose a self-navigated technique, based on the extraction of respiratory motion estimates using interleaved spiral phyllotaxis trajectories in 3D radial zero echo time (ZTE) acquisitions. These are particularly well-suited to capture the short T2* signal, characteristic of lung parenchyma, and have high acquisition efficiency allowing to generate fast temporal resolution navigators. The self-navigation technique worked robustly for different respiratory patterns and on 1.5T and 3.0T fields strengths, obtaining high quality images comparable to the ones obtained with bellows-gating.
Multislice-to-volume Prospective Motion Correction for Functional MRI Protocols at 7T
Authors: Winata Steven , Hoinkiss Daniel , Keith Graeme , al-Wasity Salim , Porter David
Published: August 2024

7 Tesla MRI provides higher signal-to-noise ratio (SNR) and spatial resolution, but is also more sensitive to motion-induced artefacts. The restricted environment within 7T scanners make non-hardware options for motion correction attractive. In this abstract, we investigate the use of the markerless, image-based, real-time Multislice Prospective Acquisition Correction (MS-PACE) technique for functional MRI protocols at 7T. This multislice scheme allows for a sub-TR motion detection and correction. It is demonstrated that the technique is able to correct longer-term motion components occurring during the acquisition.
Accuracy and test-retest repeatability of stiffness measurement with MR Elastography: a multi-center phantom study
Authors: Ozkaya Efe , Kennedy Paul , Chen Jun , Bane Octavia , Dillman Jonathan , Jhaveri Kartik , Ohliger Michael , Rossman Phillip , Tkach Jean , Venkatesh Sudhakar , Ehman Richard , Taouli Bachir
Published: August 2024

The purpose of our multicenter study was to determine the accuracy and test-retest repeatability of stiffness measured with MRE in phantoms. Three phantoms with known stiffness (2.4, 4.4, and 7.5 kPa) were circulated between 5 different centers. 1.5T or 3T systems from the 3 major vendors were used for scanning with 2D GRE and/or SE-EPI MRE sequences. The reference was based on measurements in the reference center made at the start and end of study. For all 3 phantoms the mean accuracy error for the 4 testing centers was 10.2%, while test-retest repeatability error was 2.9% for all centers.
Glycogen Imaging of The Human Liver Using GraspNOE-Dixon
Authors: Xu Xiang , Leforestier Rodolphe , Xia Ding , Feng Li
Published: August 2024

We aim to translate the glycogen imaging approach to clinical scanners for human liver imaging. By combining saturation transfer preparation and Golden-angle Radial Sparse Parallel (GRASP) imaging, we can achieve steady-state saturation suitable for generating glycogen nuclear Overhauser enhancement (NOE) contrast and free-breathing imaging readout. Furthermore, we incorporated multi-echo acquisition, enabling NOE quantification in water-only images without fat influence. In this project, we demonstrated the effect of fat signal in z spectra from the composite images and the removal of such effect in z spectra from water only images. We also validated the glycoNOE signal using a fasting protocol.
Heterogeneity of liver stiffness in chronic HBV infection: Influence on concordance between MRE-based fibrosis staging and biopsy staging
Authors: Li Chao , Li Mingkai , Jin Xin , Dong Mengshi , Han Yu , Yin Meng , Chen Jun , Glaser Kevin , Ehman Richard , Wang Jin
Published: August 2024

Chronic hepatitis B (CHB) viral infection can lead to liver fibrosis. Liver biopsy, the gold standard for liver fibrosis assessment, is invasive and carries risks of complications and sampling errors. MR elastography (MRE) is regarded as the most accurate noninvasive tool for evaluating liver fibrosis. In this study we characterized the spatial heterogeneity of liver stiffness depicted by MRE in patients with CHB and found heterogeneity at all pathological fibrosis stages. The severity of spatial heterogeneity affected the concordance between MRE-based and pathology-based fibrosis staging.
Quantitative Digital Histological Analysis and Comparison to Proton Density Fat Fraction in Patients Undergoing Weight Loss Surgery
Authors: Joshi Devashish , Harris David , Panagiotopoulos Nikolaos , Batakis Danielle , Grunvald Eduardo , Zhang Xiaofei , Agni Rashmi , Horgan Santiago , Funk Luke , Sirlin Claude , Reeder Scott
Published: August 2024

The goal of our study was to correlate quantitative digital microscopic histological markers of hepatic steatosis with MRI-PDFF and demonstrate that microenvironment characterization can be used to evaluate hepatic microstructure in NAFLD for future MRI-based studies. Patients were recruited to undergo weight loss surgery during which a liver biopsy was performed. The biopsies were analyzed for steatosis proportionate area (SPA) and characterization of fat droplets. The SPA strongly correlated to the pathologist grading and MRI-PDFF and the liver fat content strongly correlated with the number of fat droplets. Our work demonstrated the feasibility of using MRI to characterize liver microstructure.
MRI-based liver iron quantification using refocused gradient-echo (bSSFP): initial results
Authors: Wunderlich Arthur , Cario Holger , Götz Michael , Beer Meinrad , Schmidt Stefan
Published: August 2024

Purpose: To evaluate the feasibility of using a balanced steady-state free precession sequence (bSSFP) to determine liver iron content (LIC). Methods: Thirty-five consecutive patients with liver iron overload were examined with bSSFP. Signal intensity ratios between liver parenchyma and paraspinal muscles were correlated with LIC reference values obtained using Ferriscan. Results: LIC values ranged from 24 to 756 µmol/g. The best SIR-to-LIC correlation was obtained with 3.5 ms repetition time and 17° excitation flip angle. Conclusion: bSSFP is suitable to determine LIC. Its advantages are high SNR efficiency and the ability to acquire the entire liver in a breath hold.
Impact of Iron Particle Sizes on R2* Estimation in Phantoms Mimicking Hepatic Iron Overload and Steatosis Using MRI
Authors: Brasher Sarah , Chan Annie , Khan Ayaz , Abramson Zachary , Morin Cara , Tipirneni-Sajja Aaryani
Published: August 2024

Size and concentration of iron will affect the dephasing of an MRI signal. However, iron particle size is often unaccounted for in phantom studies investigating iron overload. In this study, phantoms utilizing iron nanoparticles of different diameters were used to mimic in vivo iron deposits, and R2* quantification was analyzed using different signal models. Our results show that R2* was higher and more unstable in phantoms with iron particles of 500nm diameter in comparison to those with 250nm and 130nm particles potentially due to clustering. High iron concentrations and large iron particle sizes were also shown to confound fat quantification.
High-resolution PROPELLER T2-weighted imaging of the prostate with deep learning reconstruction: a phantom and clinical preliminary study
Authors: Nakamoto Atsushi , Onishi Hiromitsu , Tsuboyama Takahiro , Ota Takashi , Fukui Hideyuki , Yano Keigo , Kiso Kengo , Honda Toru , Matsumoto Shohei , Tatsumi Mitsuaki , Tarewaki Hiroyuki , Koyama Yoshihiro , Wakayama Tetsuya , Wang Xinzeng , Tomiyama Noriyuki
Published: August 2024

The image quality of high-resolution PROPELLER T2WI combined with deep learning reconstruction (DLR) in prostate MRI was evaluated by the phantom and clinical studies. In the phantom study, noise reduction was achieved by DLR, and spatial resolution was remarkably improved in PROPELLER T2WI compared to Cartesian T2WI. In the clinical study, DLR showed a significant improvement in signal-to-noise ratio, and the qualitative analyses showed reduced image noise and improved spatial resolution, with PROPELLER T2WI DLR images showing the highest overall image quality. PROPELLER T2WI with DLR would be promising technique to improve the image quality of T2WI in prostate MRI.
Positive Predictive Value of Multiparametric MRI in Detection of Prostate cancer: A Tertiary Center Retrospective Study
Authors: Franks Zachary , Rosenberg Jarrett , Fan Richard , Sonn Geoffrey , Ghanouni Pejman
Published: August 2024

Prostate Imaging Reporting and Data System (PIRADS) guidelines are used as a standard to help radiologists diminish variation in the acquisition, interpretation, and reporting of multiparametric magnetic resonance imaging (mpMRI) for prostate cancer diagnosis. However, the performance of mpMRI has been shown to vary across radiologists. A retrospective study was performed at a tertiary care center to assess the range of positive predictive values (PPV) across individual radiologists interpreting mpMRI in detecting any prostate cancer compared to targeted MR-US guided fusion biopsy pathology results.
Estimated quantitative relaxation mapping calculated from Multiple-Repetition Multiple-Echo (MRME) based DWI acquisition in prostate
Authors: Ueda Yu , Tamada Tsutomu , Kido Ayumu , Moriya Kazunori , Shibata Shigeru , Takeuchi Mitsuru , Yamamoto Akira , Obara Makoto , Cauteren Marc
Published: August 2024

It has been reported that synthetised DW images with short TR and zero TE, generated from quantitative relaxation parameters, improved lesion contrast in prostate. In this study, we investigate the added value of the estimated T1 and T2 values in differentiating benign from malignant lesion in suspicious cancers with PI-RADS category 3, potentially reducing unnecessary biopsies. In addition to the conventional DW images at b-values of 1000 and 2000, ADC map, and estimated T1 and T2 maps, synthetised DW images can be acquired in approximately 4 minutes, an acceptable scan time in clinical practice.