bluuebunny/crossref_metadata_2025 huggingface dataset:
Nodular change of the cervical nerve root on quantitative double-echo steady-state in cervical spondylosis
Authors: Nitta Keisuke , Yokota Hajime , Sada Takayuki , Kurosawa Ryuuna , Matsumoto Koji , Namiki Takashi , Yoneyama Masami , Masuda Yoshitada , Uno Takashi
Published: August 2024

Evaluation of intervertebral foramen stenosis is essential in the diagnosis of cervical spondylosis. However, that is not easy because the intervertebral foramen is thin. We focused on the nodular change of the cervical nerve root, which is often visualized in patients with cervical spondylosis. We investigated the relationship between nodular changes and intervertebral foramen stenosis and confirmed the correlation between them. Thus, the identification of the nodular change may be helpful in the diagnosis of cervical spondylosis.
High Resolution Spinal Cord Imaging at 7T with Rosette Trajectory and Compressed Sensing.
Authors: Mahmud Sultan Zaman , Adnani Seyedeh Nasim , Denney Thomas S. , Bashir Adil
Published: August 2024

MRI is very useful to investigate spinal cord pathologies non-invasively. However, signal to noise ratio (SNR), spatial resolution and motion artifacts are some of the main challenges in spinal cord MRI. Ultra high field MRI such as 7T, can improve the SNR enabling high spatial resolution. The inherent property of low susceptibility to motion of non-Cartesian imaging technique such as Rosette, can improve the motion related artifacts. So the goal of this study was to develop a technique for high-resolution spinal cord imaging at 7T using Rosette MRI.
An automatic tool for lumbar deformities and intervertebral disc degeneration using deep-learning based 3D segmentation
Authors: Liang Yao-Wen , Kuo Chao-Hung , Chiu Feng-Mao , Lin Ting-Chun , Lan Yu-Hao , Wang Chih-Yu , Chen You-Yin
Published: August 2024

Degenerative alterations are the most common cause of lumbar spinal stenosis (LSS) in seniors. LSS is detected more often due to enhanced imaging technology and an aging population. Imaging data help individuals with chronic symptoms considering invasive therapy. This study combined the approach of assessing disc degeneration with stenosis assessment, using a deep learning-based segmentation module and a home-made autonomous measuring system.
Application of Water-Fat Imaging in Spinal Diseases: comparison with conventional T1-weighted and T2-weighted STIR Images
Authors: Wang Nan , Li Guobin , Zhang Shuheng , Yu Dan , Dai Yongming , Song Qingwei
Published: August 2024

Water-Fat Imaging (WFI) based on chemical shifts can provide excellent separation of water and fat in tissue. This work investigated the application of WFI to spinal diseases. The diagnosis performances were compared with the T1-weighted (T1W) and T2-weighted short-TI-inversion-recovery (T2W STIR) sequence. For hyperosteogeny, spinal metastasis, and disc herniation, the WFI showed comparable performance as the combination of T1W and T2W STIR imaging within a much shorter acquisition time.
Differentiation of progressive disease from pseudo-progression using Synthetic MRI and MUSE-DWI in patients with glioblastoma.
Authors: Lv Ruirui , Ma Wenfu , Xiong Yuhui , Yong Peng , Zheng Jiarui , Yang Xuhong , Wang Xiaodong
Published: August 2024

This work sought to investigate the performance of synthetic MRI(Sy-MRI) and MUSE-DWI in differentiating progressive disease (PD) from pseudo-progression (PsP). It was concluded that the pre-contrast T1(T1-pre) and post-contrast T1(T1-Gd) from synthetic MRI can be used as novel quantitative imaging biomarkers for discriminating PD from PsP. The combination of T1-pre, T1-Gd and ADC may explore as an effective strategy to improve the ability for discriminating PD from PsP, and provide a basis for clinical follow-up diagnosis and treatment.
High b-value diffusion-weighted imaging of glioblastoma on an MR-Linac
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

Hyperintense regions on high b-value DWI (HRDs) may reflect hypercellular tumour and are of interest for radiotherapy dose escalation. However, the extent to which diffusion restriction versus prolonged T2 creates these hyperintensities is not known. Additionally, the dynamics of HRDs during radiotherapy are not fully characterized. In 35 glioblastoma patients treated on a 1.5T MR-Linac, we found HRDs shrank during treatment and extended beyond the gross tumour volume. Apparent diffusion coefficient was reduced and T2 was elevated in HRD compared to the remainder of the clinical target volume, implying that both diffusion restriction and prolonged relaxation are responsible for HRDs.
Differentiation of intracranial solitary fbrous tumor from transitional meningioma using apparent difusion coefcient histogram analysis
Authors: Liu Xianwang , Han Tao , Liu Hong , Zhou Junlin
Published: August 2024

This study investigates the value of whole volume apparent diffusion coefficient (ADC) histogram analysis in distinguishing intracranial solitary fibrous tumor (SFT) and transitional meningioma (TM). The method was to compare the differences between ADC histogram parameters in them and explore the relationships between these parameters and Ki-67 expression. Our research demonstrates that SFT with higher variance, lower AP1, and AP10. Significant correlations were observed between these parameters and Ki-67 expression. The best diagnostic performance was obtained by variance. Therefore, we consider that the whole volumetric ADC histogram analysis is a feasible tool for non-invasive distinguishing between SFT and TM.
3D Balanced Steady-State Free Precession (bSSFP) Imaging on an Ultra-Low-Field 0.055T MRI System
Authors: Ding Ye , Su Shi , Xiao Linfang , Zhao Yujiao , Hu Jiahao , Zhang Junhao , Lau Vick , Man Christopher , Leong Alex , Wu Ed
Published: August 2024

Recently, there has been an impetus to develop ultra-low-field (ULF) MRI technologies, which present opportunities for low-cost and portable imaging in point-of-care scenarios. Balanced steady-state free precession (bSSFP) is a time-efficient imaging sequence yet its feasibility at ULF remains unexplored. In this study, we implemented bSSFP sequence at 0.055T, and successfully demonstrated phantom, brain and extremity imaging.
Overhauser-enhanced MRI at ultra-low fields: a new system for imaging of free radicals in rodents
Authors: Boudries Dahmane , Massot Philippe , Parzy Elodie , Seren Seda , Mellet Philippe , Franconi Jean-Michel , Marque Sylvain , Fidler Florian , Wintzheimer Stefan , Mützel Markus , Thiaudiere Eric
Published: August 2024

A new MRI system at Ultra-low field (206 µT) was designed for Overhauser-enhanced MRI. It allows both conventional MRI with pre-polarization at 20 mT and Dynamic Nuclear Polarization in the 70MHz range in living rats. Anatomical images in 3D allowed a correct visualization of the rat body shape. OMRI with injected or instilled stable and non-toxic nitroxides permitted to detect the free radicals in the lungs, the kidneys and the bladder. The work opens the way of molecular imaging of abnormal proteolysis in the context of a variety of diseases in large animals.
Multi-reader evaluation of real-time MRI of the actively moving wrist at 0.55 Tesla
Authors: Chaudhari Abhijit , Boutin Robert , Lim Yongwan , Cui Sophia , Szabo Robert , Nayak Krishna
Published: August 2024

We acquired real-time MRI of the actively moving wrist in humans utilizing a high-performance 0.55T system. Resulting images and associated static wrist scans were assessed by two expert readers blinded to acquisition parameters. Our results show that images acquired at a high temporal resolution of 12.6 ms per frame demonstrate minimal image degradation compared to images acquired at temporal resolution of 100 ms or higher, and enable improved characterization of wrist motion. These benefits support further studies to assess high-performance 0.55T systems for the evaluation of dynamic dysfunction of the wrist.
Outer Volume Saturation using Adiabatic Inversion Pulses in an Inhomogeneous Transmit Field
Authors: Gomes Muller , Mustafi Sourajit , Sadinski Meredith , Selvaganesan Kartiga , Nacev Aleksandar
Published: August 2024

A method for saturating the outer volume in a single sided low field MRI scanner has been developed. By saturating the outer volume using this method, magnetization from regions where the gradient fields are highly nonlinear may be removed from the image, resulting in less image artifacts.
Mask-free T2* and R2* mapping with dual multi-dimensional integration (dMDI)
Authors: Ye Yongquan , Xu Jian , Zhang Zhongqi , Zhang Yan , Zhao Qiang , Xu Jiajia , Yuan Huishu
Published: August 2024

A dual MDI strategy was developed and demonstrated to achieve T2* and R2* mapping that are both highly delineated between noise backgrounds and normal tissues as well as spikes free, thus eliminating the need for routine noise masking or manual segmentation.
Insensitive to Off-Resonance 3D T1/T2 Mapping SPGR/bSSFP using Dictionary-Matching: Application to the Prostate at 3T
Authors: Coronado Ronal , Castillo-Passi Carlos , Besa Cecilia , Irarrazaval Pablo
Published: August 2024

Balanced Steady State Free Precession (bSSFP) has been successfully used to estimate T2 maps (DESPOT2), but bSSFP is prone to off-resonance artifacts. These artifacts affect the reconstruction of the T2 maps. We propose a dictionary-matching reconstruction using the signal model of bSSFP and spoiled gradient echo (SPGR). We tested this approach with simulation, 3D phantom and 3D in-vivo prostate acquisitions. In all of them, the off-resonance banding artifacts are greatly reduced, which is reflected in reduced NRMSE values. This method allows using a faster sequence with high SNR to quantify complicated body regions like the prostate.
Compressed sensing vs multiple overlapping echo detachment in acceleration efficiency of DL-based quantitative parametric mapping
Authors: Qin Qingdang , Wang Jiechao , Wu Zhigang , Cai Shuhui , Cai Congbo
Published: August 2024

Compressed sensing (CS) relies on random under-sampling measurements and has been the primary technique to accelerate quantitative parametric mapping (QPM). The multiple overlapping-echo detachment (MOLED) technique proposed recently is a novel technique to realize quantitative parametric mapping in a single shot within around 100 milliseconds. However, the two techniques still lack a systematic comparison of acceleration performance in QPM. For the first time, we analyze and compare the performance of these two techniques under the same conditions via numerical experiments. The results show that MOLED outerperforms one-dimensional under-sampling CS acceleration technique in T2 quantification.
Quantitative Susceptibility Mapping of Human Kidney Using Multi-echo Gradient Echo with Dual TR: A Preliminary Study
Authors: Mei Yingjie , Guo Yihao , Liu Qiang , Deng Kan , Wu Peng , Yan Chenggong , Xu Yikai , Feng Yanqiu
Published: August 2024

QSM of human kidney remains challenging due to chemical shift and respiratory motion. We utilized a dual-TR based multi-echo gradient echo (GRE) sequence and proposed an in-phase method to solve nonconvex optimization problem in water-fat separation for QSM of human kidney. The kidney QSM data were successfully acquired and calculated in all four volunteers. The kidney QSM implemented in our study could provide valuable imaging markers for the assessment of pathophysiological changes of kidney diseases.
High Resolution Luminal Water Imaging for Prostate Cancer Diagnosis and Grading
Authors: Mohtajeb Maryam , MacMillan Erin , Gilbert Guillaume , Kozlowski Piotr
Published: August 2024

Current prostate cancer diagnosis and grading techniques have several limitations, which dictates further endeavors toward developing a more accurate approach. Luminal water imaging (LWI) has demonstrated superior diagnostic accuracy than the current multiparametric MRI standardized protocol. In this new application, we further optimized LWI acquisition by decreasing the in-plane resolution without sacrificing SNR by applying two different reduced field-of-view techniques. Our new sequences provide improved in-plane resolution to delineate anatomical details and provide high-quality data for LWI analysis. This new LWI acquisition could replace the lengthy multiparametric MRI that suffers from technical challenges, inferior diagnosis accuracy, and a required contrast agent injection compared to LWI.
MR-based Radiomics Models for Predicting Pathological Complete Response in Locally Advanced Rectal Cancer: A Two-Centre, Multi-Vendor Study
Authors: Wei Qiurong , Chen Weicui , Mao Liting , Deng Kan , Yan Zhaoxian , Huang Weikang , Liu Xian
Published: August 2024

The response to neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC) is especially important for prognostic and management decisions. In this study, we used cross-vendor data from two centers to validate the generalization ability of radiomics model based on multiparametric-MRI (MP-MRI) for predicting pCR and to compare the discriminatory performance of different classifiers. Our results demonstrated that radiomics can be used to predict pCR. The clinical-radiomics model had superior performance compared to the radiomics model and clinical model. Furthermore, the RF classifier outperformed the other classifiers in prediction.
The importance of multi-reader assessment for external validation of prostate lesion classification models using quantitative mpMRI.
Authors: Syer Tom , Dikaios Nikolaos , Parry Thomas , Brembilla Giorgio , Brizmohun Mrishta , Singh Saurabh , Heavey Susan , Pye Hayley , Whitaker Hayley , Mallett Sue , Atkinson David , Punwani Shonit
Published: August 2024

Machine learning for classifying prostate mpMRI lesions may help reduce unnecessary biopsies. However, external validation with multiple scanners and readers is required before the clinical adoption of such models can be considered. Two readers validated a previously published and well-performing logistic regression model on an external cohort. The model performance was not generalisable and offered no advantage to using PSAd cut-offs, and there was marked variation in model score related to contour differences from different readers. This potential variability should be investigated in future models which use quantitative MRI.
Constructing different models to predict the degree of uterine prolapse based on high-resolution MRI radiomics
Authors: Wang Qian , Bi Qiu , Zheng Yijun , Wang Yaoxing , Chen Yuhui , Li Chenrong , Wang Xianhong , Wu Yunzhu , Bi Guoli
Published: August 2024

Uterine prolapse has become one of the most common chronic diseases affecting women's health and quality of life. Early detection and intervention would be important factors to delay the progress of uterine prolapse. In this study, high-resolution magnetic resonance imaging(HR-MRI) of pelvic floor combined with radiomics was used to investigate the degree of uterine prolapse. It was found that the HR-MRI radiomics can be used as an effective evaluation method, and the nomogram has the best diagnostic efficacy for predicting the degree of uterine prolapse.
The Value of Pelvic Skeletal Muscles to Identify the Low-Risk Rectal Cancers with Poor Prognosis
Authors: Fu Yu , Gao Jiayi , Li Mingyang , Zhang Huimao
Published: August 2024

The low-risk rectal cancer (RC) has no need for postoperative treatment after total mesorectal excision (TME). However, there are some low-risk RC patients without postoperative-treatments had subsequent metastasis and recurrence. Skeletal muscles are gaining more attention which shown to be associated with morbidity and mortality in caners. Therefore, this study established a radiomics model based on pelvic skeletal muscles on MRI to identify the low-risk rectal cancer (RC) with poor prognosis. Our research shows that the novel radiomic signatures could be used to predict disease-free survival (DFS) in low-risk RC to help clinicians improve the treatment decision making followed TME.
The value of dynamic contrast-enhanced MRI for discriminating tumor deposition from metastatic lymph nodes adjacent to rectal cancer
Authors: HU WEN , Chen Anliang , Liu AIlian
Published: August 2024

Tumor deposits (TD) and N stage are powerful prognostic factors for predicting the overall disease-free survival of rectal cancer patients. However, rectal cancer patients with TD are not the same as those with metastatic lymph node(MLN) in terms of treatment measures and prognosis. TD has similar performance to MLN on conventional CT/MRI images, which makes it difficult to distinguish them. Results of this study indicate DCE-MRI can effectively differentiate TD and MLN adjacent to rectal cancer, and the higher Kep and lower Ve values of rectal cancer with MLN may indicate its’ more aggressive.
Added-value of 3D amide proton transfer MRI in assessing cervical cancer: a comparison with multiple model diffusion-weighted imaging
Authors: Li Shujian , Lin Jieliang , Cheng Jingliang
Published: August 2024

This study compared the diagnostic performances of mean, minimum, and maximum values of APT SI for preoperative identifying the prognostic factors (tumor stage, subtype, grade and LVSI status) of cervical cancer with those of multi-model DWI, and examined the additive value of 3D-APT imaging combined with multi-model DWI for the preoperative characterization of cervical cancer. The results showed that 3D-APT imaging was comparable with multi-model DWI for cervical cancer typing and grading. Adding APT to DWI can significantly improve the diagnostic performance with an AUC of 0.908 to predict tumor subtype, and an AUC of 0.903 to predict histological grade.
MRA for Pulmonary Embolism to Conserve Iodinated Contrast Media During an Acute Supply Chain-related Shortage
Authors: Starekova Jitka , Chu Sheena , Bluemke David , Grist Thomas , Kusmirek Joanna , Nagle Scott , Schiebler Mark , Lubner Meghan , Nagpal Prashant , Reeder Scott
Published: August 2024

The closure of GE Healthcare’s Shanghai facility in April 2022 during the COVID-19 lockdown in China led to a major supply chain disruption of iodinated contrast media in North America. In response, our department instituted measures to conserve iodinated contrast, including the use of MRA as an alternative to contrast enhanced CTA to evaluate for pulmonary embolus (PE). Over the period of April through July of 2022, this strategy conserved an estimated 27 liters of iohexol 350 mg/ml. We report our experience on the use of MRA for diagnosis of PE in the general population during this period.
Improved non-contrast-enhanced MR Venography of lower extremities using non-triggered 3D-GRE-EPI.
Authors: Takumi Toshiki , Hamano Hiroshi , Mochizuki Tomohiro , Katsumata Yasutomo , Yoneyama Masami , Andou Shouichi , Ohno Ken , Namiki Takashi
Published: August 2024

MRI is one of a promising diagnostic of lower extremity arterial and venous disease, and non-contrast-enhanced MR angiography has an array of specific applications for numerous clinical indications. In this study, we demonstrated non-contrast-enhanced non-triggered 3D gradient-echo echo-planer-imaging (3D-GRE-EPI) can provide high quality MR Venography in lower extremities. Consequently, 3D-GRE-EPI was provided high sharpness, contrast and could distinguish veins and arteries.
Analysis of baseline and cardiac function factors affecting the image quality of contrast-free 3.0T MR coronary angiography
Authors: Zhang Gang , Xing Wei , Shen Zhiwei , Lian Jianxiu , Jiang Ke
Published: August 2024

Magnetic resonance coronary angiography (MRCA) imaging technology is still somewhat sophisticated, with numerous elements influencing image quality. This study found that for subjects with high BMI, high heart rate, and high systolic blood pressure, further optimization of imaging sequences and parameters is needed to explore individualized coronary MR imaging protocols.
Breath-hold Whole Heart Coronary MRA with Parallel Imaging, Compressed Sensing and Deep Learning reconstruction
Authors: Miyoshi Mitsuharu , Nozaki Atsushi , Okuda Shigeo , Jinzaki Masahiro , Wakayama Tetsuya
Published: August 2024

For Breath-hold Whole Heart Coronary MRA, we developed the combination of Parallel Imaging and Compressed Sensing to accelerate scan time and Deep Learning reconstruction to improve the image quality. With the combination of these techniques, we could obtain Coronary MRA with 1.8mm isotropic acquisition voxel size in a possible breath-hold scan time. Deep Learning recon effectively improved the SNR and image quality.
Diagnostic value of combined DTI and DKI imaging for diffuse axonal injury of brain
Authors: XU Ke-ning , Wang Wenjia
Published: August 2024

The values of fractional anisotropy (FA) in diffusion tensor imaging (DTI) and the mean kurtosis (MK) and mean diffusivity(MD) values in diffusion kurtosis imaging (DKI) were used to analyze diffuse axonal injury of brain Injury (DAI). We explored the diagnostic value of these three parameters in DAI and found that MK was superior to FA and MD. DTI and DKI could quantitatively analyze the severity of DAI patients and reduce the misdiagnosis rate of DAI.
Downfield 1H MRS can quantify age and hypoxia induced changes in brain NAD+
Authors: Can Emine , Martin-McNulty Baby , Kolumam Ganesh , Riegler Johannes
Published: August 2024

NAD+ is required for vital cellular processes such as redox regulation, DNA damage repair and cell signaling. There has been a growing interest in modifying NAD+ concentrations in the hope that it might increase longevity. However, there is no clear consensus on changes in NAD+ concentration due to healthy aging. Commonly used in vitro assays for NAD quantification are not suitable for longitudinal studies. We therefore implemented an in vivo downfield 1H MRS method to characterize NAD+ concentrations during aging in mice and showed that 1H MRS can detect hypoxia induced changes in brain NAD+ concentrations.
Elevated Magnetic Susceptibility Suggests Distinct Neurodegenerative Pathology in World Trade Center First Responders
Authors: Hagan Thomas , Ying Jia , Huang Chuan , Kritikos Minos , Clouston Sean , Luft Benjamin
Published: August 2024

Mounting evidence has shown that first responders to the 9/11 terrorist attack on the World Trade Center(WTC) are developing early-onset dementia but the underlying pathology driving this remains to be understood. Our team assessed the relationship between cognitive impairment and susceptibility differences in the brains of responders for the first time using quantitative susceptibility mapping(QSM). While research on Alzheimer’s disease has reported changes in QSM across several regions, we found elevated susceptibility located in the amygdala of responders with CI. Our findings bolster evidence suggesting that WTC responders are experiencing unique pathology which could point to a novel neurodegenerative disease.
Effects of peritumoral T2 hyperintensities in treated gliomas on the quantification of tumour blood flow with arterial spin labeling.
Authors: Sokolska Magdalena , Ruffle James K , Gupta Meetakshi , Markus Julia , Kosmin Michael , Jäger Hans , Nachev Parashkev , Harpreet Harpreet
Published: August 2024

Elevated tumour blood flow in treated gliomas t can be indicative of disease recurrence. TBF can be visualised and quantified with arterial spin labelling with quantification performed by scaling a perfusion-weighted image by a proton density image and a brain-blood partition coefficient, assuming mapping to a fully relaxed blood magnetisation signal. However, this assumption might not hold in T2/FLAIR hyperintense areas surrounding enhancing tumour due to much higher water content. Therefore, this work investigates blood flow quantification in three tumour compartments, enabled by recent developments in AI-generated labels of tumour components.
Pretreatment Apparent Diffusion Coefficient Value for Prediction of Relapsed and Refractory Primary Central Nervous System Lymphoma
Authors: Ko Ching-Chung , Yeh Lee-Ren , Chen Jeon-Hor
Published: August 2024

A subset of primary central nervous system lymphoma (PCNSL) may show early relapsed/refractory (R/R) disease after treatments. This study investigated the role of pretreatment apparent diffusion coefficient (ADC) values for the prediction of R/R in PCNSL. Total 52 patients with pathologically confirmed PCNSL were included, and 24 (46.2%) patients developed R/R (median time to relapse, 13 months) after treatment. The results showed female sex, complete response to first-line chemotherapy, and ADC value/ratio were significant predictors of R/R in PCNSL. Pretreatment ADC values/ratios offer objective and valuable evaluation for the treatment planning in PCNSL.
Identification of IDH genotype and tumor subtype of adult-type diffuse gliomas based on WHO CNS5 using histogram features of QSM and ADC
Authors: Sun Yifan , Yang Zheting , Song Yang , Jiang Rifeng
Published: August 2024

Preoperative prediction of glioma histological features and biological behavior is clinically important. However, few studies reported the histogram analysis of QSM in the isocitrate dehydrogenase (IDH) genotype and subtype of gliomas. In this study, we explored the value of histogram features of QSM and ADC in predicting the IDH genotype and tumor subtype of adult-type diffuse gliomas based on the fifth edition of the World Health Organization Classification of Tumors of the Central Nervous System (WHO CNS5). We found that histogram parameters based on QSM and ADC are significantly related to the IDH genotype, tumor subtype, and proliferation of glioma.
MR Varying Diffusion Curvature Imaging on Different Brain Tumors: A Preliminary Experience
Authors: Tian Chuanshuai , Hu Wentao , Dai Yongming , Chen Sixuan , Zhou Jianan , Zhang Xin , Zhang Bing
Published: August 2024

Dozens of diffusion models have been created to describe the non-Gaussian nature of diffusion. Nevertheless, many of them imply assumptions that have not been rigorously confirmed, or includes abstract parameters. The purpose of this study was to observe the characteristics of varying diffusion curvature (VDC) indicators in several types of brain tumor. D0 and D1 distribution were obtained for each subject. This study illustrates the potential of applying a simple and pure empirical non-Gaussian diffusion model VDC on brain tumor imaging.
Widened-bandwidth RF volume coil using crossed elliptical winding for Halbach-array-based portable MRI knee scanner
Authors: RAJENDRAN MEENA , HUANG SHAOYING
Published: August 2024

A widened-bandwidth RF volume coil using crossed elliptical winding pattern (symmetric in azimuthal direction) is proposed for Halbach-array-based portable MRI knee scanner. The fractional bandwidth (FBW) is 0.51% centered at 2.84 MHz (B0 = 67mT) with a high B1 field strength (57µT) and a high homogeneity (94%) within a cylindrical volume of diameter and length of both 95mm. Compared to solenoid coils of comparable dimensions, it is an increase of 18% in FBW, an improvement in homogeneity by 6.1%, and only a compromise of 1.9% in the field strength, which is the best combination.
General implementation of frequency–space reconstruction
Authors: Havu Marko , Zevenhoven Koos , Mäkinen Antti , Ilmoniemi Risto
Published: August 2024

In low-field and ultra-low-field MRI, concomitant fields can cause severe blurring and distortion in traditional Fourier reconstruction. We have developed an improved image reconstruction framework based on our previously published method that uses a frequency–space formulation. It provides more accurate reconstruction results with the cost of increased computation time. Known inhomogeneity and other field nonidealities can be incorporated into the model to improve the quality of the reconstruction. The framework will be published as open source.
Gradient non-linearity estimation in an Open MRI scanner
Authors: Mougin Olivier , Glover Paul , Bowtell Richard , Gowland Penny
Published: August 2024

Open magnet provide advantageous facility for imaging the human body in a natural way. However field inhomogeneities can reduce the utilisable imaging field-of-view. We present a simple way to map the static field inhomogeneity and the non-linear gradient inhomogeneity in order to correct them during the image reconstruction.
Quantitative Magnetization Transfer Imaging in Glioblastoma Patients using Balanced Steady-state Free Precession on a 1.5 T MR-Linac
Authors: Tran Brandon , Lawrence Liam , Chan Rachel , Tseng Chia-Lin , Detsky Jay , Soliman Hany , Sahgal Arjun , Lau Angus
Published: August 2024

Quantitative magnetization transfer (qMT) imaging could be used to assess tumor response on an MR-Linac. However, qMT protocols which use an off-resonance saturation pulse are slow and does not have the 3D coverage necessary to assess tumor response. We implemented a fast 3D balanced steady-state free precession qMT protocol on the MR-Linac. Six glioblastoma patients were scanned on the MR-Linac at weekly intervals during treatment. qMT parameter maps derived using non-linear least square fitting show similar contrast to other qMT protocols. Within-subject coefficient of variation was higher than values found in literature for off-resonance qMT protocols.
Fast quantitative T2 mapping at ultra-high field using sparse sampling and dictionary-based reconstruction
Authors: Schmidt Jochen , Radunsky Dvir , Scheibe Patrick , Ben-Eliezer Noam , Trampel Robert , Weiskopf Nikolaus
Published: August 2024

Quantitative T2 mapping at ultra high-field via multi-echo spin-echo acquisitions suffers from bias introduced by pronounced transmit field inhomogeneities. Hence, accurate signal modeling is vital. Futhermore, high-resolution imaging results in longer scan times, which need to be compensated by k-space undersampling. Conventional undersampling schemes for multi-echo approaches skip identical phase encoding areas for all echo readouts. Image reconstruction quality might be improved by varying the sampling across echoes and using a low rank reconstruction approach. A multi-echo acquisition combining sparse undersampling with a dictionary modelling method was successfully used to acquire accurate T2 at 7T with a high acceleration.
T2* Mapping to Assess Hashimoto's Thyroiditis vs Healthy Thyroid at 3.0T: Feasibility
Authors: Ooms Nathan , Monsevais Humberto , Dydak Ulrike
Published: August 2024

Hashimoto Thyroiditis is an autoimmune disease that largely effects women, and can cause fatigue, unexplained weight loss or gain, enlargement of the thyroid gland, and other symptoms. We are proposing utilizing T2* mapping to quantify the thyroid gland in the presence and absence of Hashimoto's Thyroiditis. Very little has been studied using T2* techniques in the thyroid gland, and what has been studies has focused on evaluating for nodules and cancer. We hope to broaden the capabilities to establish normal ranges and evaluate the effects of Hashimoto's Thyroiditis.
Diffusion Tensor Imaging Parameters in ALS Post Mortem In Situ versus Ex Situ MR Acquisitions
Authors: Neuhaus Dominique , Wendebourg Maria , Scheurer Eva , Berger Celine , Bauer Melanie , Haas Tanja , Schlaeger Regina , Lenz Claudia
Published: August 2024

The development of magnetic resonance imaging (MRI) biomarkers in neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) might alleviate current challenges. Generally, post mortem (PM) ex situ quantitative imaging is used for the validation of potential biomarkers, which shows several limitations. In this study, PM MRI brain scans of three deceased ALS patients have been conducted. The objective was to identify differences between in situ and ex situ scans regarding the diffusion tensor imaging (DTI) measures fractional anisotropy (FA) and mean diffusivity (MD). A significant difference was found for the FA values in white matter.
Quantitative DWI in patients with hepatocellular carcinoma: effects of simultaneous multi-slice acquisition and gadoxetic acid injection
Authors: Yang Ting , Ye Zheng , Yao Shan , Li Qing , Song Bin
Published: August 2024

Diffusion weighted imaging (DWI) and gadoxetic acid-enhanced magnetic resonance imaging (MRI) are important in diagnosing hepatocellular carcinoma (HCC). Previous studies have validated that gadoxetic acid administration during enhanced MRI improves signal-to-noise ratio without influencing apparent diffusion coefficient (ADC), while the impact of simultaneous multi-slice (SMS) technique on the measurement of ADC is still unknown. Our study assessed the influence of gadoxetic acid administration on ADC values of liver with and without SMS acceleration. We found that SMS technique and gadoxetic acid administration did not affect the ADC values of liver parenchyma and HCC.
Combined Multiparameter Quantitative MRI of PD, T1, T2 and the Diffusion Tensor with MP6-qMRI-Turbo Spin Echo with SPLICE
Authors: Hua Ning , Ellison Andrew , Zhao Yansong , Jara Hernan
Published: August 2024

Purpose: To augment the qMRI multi-parametricity of the Triple TSE to additionally include primary diffusion tensor imaging (DTI) functionality and with seamless geometric compatibility with the nPD, T1, and T2 maps of the Triple-TSE framework. Methods: qMRI maps were generated with algorithms based on Bloch and Bloch-Torrey equations. Results: histogram analyses for the phantom and volunteer reveal well behaved qMRI data for nPD, T1, T2, MD, and FA. Conclusion: Creating a unified clinical MP-qMRI protocol for PD, T1, T2 and diffusion tensor seems within reach.
Application of Deep Learning-based Reconstruction for Diffusion Kurtosis Imaging in Head and Neck Cancer
Authors: Konar Amaresha Shridhar , Shin Jaemin , Paudyal Ramesh , Shah Akash , Dave Abhay , Fung Maggie , LoCastro Eve , Banerjee Suchandrima , Lee Nancy , Shukla-Dave Amita
Published: August 2024

A Deep learning (DL)-based reconstruction is a promising method to achieve higher resolution for diffusion-weighted Kurtosis imaging (DKI) without increasing signal averaging. The DKI phantom and patient results demonstrated improved image quality and reduced Gibbs (ringing) artifact, aiding in the robust estimation of Dapp and Kapp. In all phantom and patient data, the standard deviation of Dapp and Kapp measured in images reconstructed without DL was higher than in images reconstructed using DL. The NEX=1 significantly reduced the multi-b-value data acquisition time, and the DL-based reconstruction can produce images comparable to the standard NEX=2 or 4, depending on the b-value.
Dependence of PDFF Measurement Accuracy on Location, Resolution, and Field Strength – a Phantom Experiment
Authors: Panagiotopoulos Nikolaos , Rutkowski David , Anagnostopoulos Alexandra , Oechtering Thekla , Hernando Diego , Brittain Jean , Reeder Scott
Published: August 2024

The purpose of this work was to determine the spatial dependence of PDFF measurements at both 1.5T and 3.0T in a phantom setting. We showed that bias in CSE-MRI-based PDFF measurements is low when performed in areas not more than 20 cm from the isocenter in any direction. These results have immediate practical relevance for clinical routine, e.g., in prescribing MRI acquisitions for clinical PDFF measurements and for the correct placement of pocket phantoms in the MRI bore when used as quality assurance tools.
Combined motion and B0 correction of susceptibility weighted imaging with jointly acquired FID and spherical navigators
Authors: Hewlett Miriam , Liu Junmin , Drangova Maria
Published: August 2024

Jointly acquired FID and spherical navigators were applied for prospective correction of motion and retrospective correction of zeroth order field offsets in a susceptibility weighted imaging protocol. Initial results showed a significant reduction in motion artifacts with prospective motion correction, quantified using structural similarity index. Retrospective B0 correction provided an additional improvement in image quality (also statistically significant). Future work will investigate methods to reduce residual artifacts, as well as incorporating the navigator within deadtime in the sequence to reduce scan time.
Velocity-Encoding Navigator for First-Order Motion Compensation in Diffusion MRI
Authors: Li Bo , Ernst Thomas
Published: August 2024

Uncorrected head rotations during diffusion weighted imaging (DWI) can induce gradient imbalances that may shift the echo outside of the k-space window and cause signal dropouts. Therefore, we developed a rotational velocity navigator (~10ms duration) that is acquired immediately after each excitation and estimates the rotational velocities perpendicular to the diffusion gradient. The accuracy of estimated velocities was 4.1°/s relative to an optical tracking system (“gold standard”). Ultimately, the rotational velocities can predict the gradient moment error in first order, and a gradient blip can be applied to recenter the echo in k-space.
Inline Retrospective Motion Correction and Dynamical Alignment Using an Optical Markerless Motion Tracker
Authors: Lindberg Ulrich , Glimberg Stefan , Crelier Gerard , Buehrer Martin , Larsson Henrik
Published: August 2024

Using an external motion tracking system for recording head movement during MR-acquisition and a modified version of the Philips reconstruction software (Recon2.0) that enables phase re-alignment and re-gridding of acquisition profiles during the standard immediate reconstruction process, we present a fully integrated retrospective motion correction solution that deliver both corrected and non-corrected images to the user and allows for the immediate visual assessment of the correction quality upon acquisition.
Multi-Echo MRI Motion Artifact Reduction via Knowledge Interaction Learning for Better SWI Enhancement
Authors: Al-masni Mohammed , Lee Seul , Kim Sewook , Gho Sung-Min , Choi Young Hun , Kim Dong-Hyun
Published: August 2024

Patient movement during MRI scan can cause severe degradation of image quality. In Susceptibility-Weighted Imaging (SWI), several echoes are measured during a single repetition period, where the earliest echoes show less contrast between various tissues, while the higher echoes are more susceptible to artifacts and signal dropout. This paper proposes a data-driven retrospective deep learning method by taking the advantage of interactively learning multiple echoes together through sharing their knowledge using unified training parameters. The proposed method allows to share information and gain an understanding of the correlations between multiple echoes towards generating high-resolution susceptibility enhanced contrast images.
Evaluation of body motion at various patient position in a 0.5 T Upright scanner
Authors: Bortolotti Laura , Clennell Isabel , Bradbury Amy , Mougin Olivier , Glover Paul , Bowtell Richard , Gowland Penny
Published: August 2024

Body motion at nine typical upright MRI poses (standing, seated, supine), have been characterised for several body positions (head, shoulder, sternum, hip) for 20 subjects over 30 s (free breathing); and 20 s (breath hold) and for 9 subjects over 10 minutes. Free-standing caused most motion; lying supine caused least. The use of a body support and breath-holding reduced motion. Net motion was similar over 50-1000 ms sampling periods. Respiratory-related motion could be removed from tracking data. The degree of motion identified in this work will inform future respiratory triggering and motion correction work.
Fast multi-slice liver water T1 mapping using single-shot continuous inversion recovery spiral imaging
Authors: Moquillaza Elizabeth Huaroc , Weiss Kilian , Lee Yoo Jin , Stelter Jonathan , Amthor Thomas , Koken Peter , Makowski Marcus R. , Braren Rickmer , Doneva Mariya , Karampinos Dimitrios C.
Published: August 2024

Liver T1 mapping can characterize liver alterations in diffuse or focal (e.g. metastatic) liver disease, but it is currently limited to acquisitions of a single-slice per breath-hold. We propose a continuous inversion recovery methodology combining a single-shot gradient echo spiral readout, Dixon processing for water-fat separation and dictionary-based analysis for water selective T1 mapping in the liver at 3T. The spiral readout is employed for a high k-space sampling efficiency, enabling acquisitions with only 1.2s per slice. The method allows multi-slice full-liver water T1 mapping either in a single 11s-breath-hold or in a respiratory-triggered acquisition.
Towards Non-Invasive Diagnosis of NASH: Retrospective Fat Correction of MP2RAGE T1 Improves Correlation with Liver Fibrosis Stage
Authors: Duffy Andrew , Maheta Parth , Costa Andreu F. , Clarke Sharon , Stueck Ashley , McLeod Magnus , Rioux James
Published: August 2024

There is significant interest in non-invasive biomarkers for staging of liver fibrosis in non-alcoholic fatty liver disease (NAFLD) to reduce the need for biopsy. T1 correlates with fibrosis but can also be influenced by fat, and while Dixon fat-water separation can remove this effect, such methods are uncommon in clinical T1 mapping sequences. In this work, we demonstrate a retrospective correction to estimate the T1 of liver tissue based on MP2RAGE without fat-water separation. This enables fat compensation in a wider range of acquisitions and improves the potential clinical utility of T1 as a biomarker for liver fibrosis.
Fast Free-Breathing 3D T1ρ Abdominal Imaging Using an Efficient Diamond Radial Sampling Strategy at 3T
Authors: Wu Can , Peng Qi , Jafari Ramin , Zhao Yansong , Yu Victoria , Otazo Ricardo
Published: August 2024

An efficient diamond radial sampling strategy was proposed for free-breathing 3D T1ρ abdominal imaging at 3T. The phantom experiment shows that diamond radial sampling provides T1ρ measurement values comparable to that of 3D Cartesian and radial stack-of-stars sampling. In-vivo volunteer studies illustrate that diamond radial sampling is superior to Cartesian sampling, where image quality is significantly compromised by breathing motion artifacts. In addition, scan time can be drastically reduced using the fast MAPSS method. This work demonstrates the feasibility of quantitative free-breathing 3D T1ρ imaging with diamond radial sampling in the abdomen.
Sub-differentiation of PI-RADS 3 lesions in TZ by advanced diffusion-weighted imaging to aid the biopsy decision process
Authors: Zhou Kun-Peng , Bian Jie , Huang Hua-Bin , Bu Chao , Xie Li-Zhi
Published: August 2024

The aim of this study was to investigate the use of advanced diffusion-weighted imaging (IVIM, stretched exponential model and DKI) to sub-differentiation of TZ PI-RADS 3 lesions and aid the biopsy decision process. Finally, the logistic model could correctly classify 89.39% of the subjects. The results of ROC analysis showed that AUC was 0.9197, CI 95%: 0.8736-0.9659. Sensitivity, specificity, positive predictive value and negative predictive value were 92.1%, 80.4%, 93.9% and 75.5%, respectively. Therefore, advanced diffusion-weighted imaging can predict PCa in TZ PI-RADS 3 lesions and inform the decision-making process of whether or not to perform a biopsy.
Study of deep-learning models for detection and localization of early-stage clinically significant prostate cancer on mpMRI
Authors: Sun Zhaonan , Wang Xiaoying , Wang Kexin
Published: August 2024

The purpose of this study was to explore the best sequences for fully automated detection and localization of early-stage csPCa with a PSA range of 4-10 ng/mL.1628 prostate mpMRI examined with seven scanners were retrospectively enrolled. A training dataset (n=1428) was used to train models, i.e., a diffusion model was trained with diffusion-weighted imaging, and a biparametric model was trained with diffusion-weighted imaging and T2-weighted imaging. A hold-out test dataset (n=200) was reserved for validation. Our research shows that the diffusion model trained using ADC and DWI achieved best performance in detection and localization of early-stage csPCa.
Sub-differentiation of intermediate risk prostate cancer by advanced diffusion-weighted imaging
Authors: Zhou Kun-Peng , Huang Hua-Bin , Liu Long , Bian Jie , Xie Li-Zhi
Published: August 2024

The aim of this study was to investigate the use of advanced diffusion-weighted imaging to sub-differentiation of intermediate risk group PCa and aid treatment decision process. Finally, the logistic model was statistically significant, χ2=90.969, p<0.001. The model could correctly classify 86.40% of the subjects. The results of ROC analysis showed that area AUC was 0.9429, CI 95%: 0.9054-0.9805. Sensitivity, specificity, positive predictive value and negative predictive value were 88.06%, 84.31%, 88.06% and 84.31%, respectively. The results of this research may indicate that advanced diffusion-weighted imaging can sub-differentiate intermediate risk group PCa and aid the decision process of treatment.
Initial exploration of the potential of diffusion-weighted MRS for the evaluation of prostate pathology
Authors: Rizzo Rudy , Stamatelatou Angeliki , Simsek Kadir , Van Asten Jack , Kreis Roland , Heerschap Arend , Scheenen Tom
Published: August 2024

Prostate pathologies like cancer and prostatitis cause alterations in tissue microstructure that are reflected in signal variations on diffusion-weighted MRI or MR relaxometry. Diffusion-weighted MR Spectroscopy (DW-MRS) allows specific characterization of tissue microstructure by quantifying both concentration and diffusion properties of MR-observable metabolites. In this work, an optimized DW-MRS protocol tailored to overcome the inherent challenges of prostate measurements is deployed. Initial results on potential alterations of metabolite concentrations and diffusivities (ADCs) are reported for prostate cancer and prostatitis. The preliminary findings are tentatively explained by microstructure alterations of the prostate tissue.
A clinical validation study of synthetic high b-value reduced filed-of-view diffusion weighted imaging on prostate
Authors: Zhou Qiqi , Liu Weiyin , Tang Qian , Sang Ling , Chen Wen , Xu Lin
Published: August 2024

High b-value diffusion weighted imaging is clinically challenging due to its inherently low SNR and prone to presence of severe eddy current distortion due to utility of large diffusion sensitization gradient, not to mentioned high-resolution prostate DWI. In our study, 5b-protocol rFOV-syDWIswith pros of short scan time provided better lesion clarity and higher image quality. Moreover, synthetic ADCs offered reliable and satisfactory diagnostic value as scanned 13b-protocol DWIs despite significant difference of mean and median were found between syADCb=1500 and sADCb=1500 in PCa but not in hyperplasia, indicating diagnosis withrFOV-syADCs should be careful when referring to rFOV-sADCs.
Deep learning-based prognostic model using non-enhanced cardiac cine MRI in patients with heart failure.
Authors: Gao Yifeng , Zhou Zhen , Zhang Bing , Guo Saidi , Bo Kairui , Li Shuang , Zhang Nan , Wang Hui , Guang Yang , Zhang Heye , Liu Tong , Lian Jianxiu , Xu Lei
Published: August 2024

We proposed a multi-source deep-learning model including traditional functional parameters and myocardial strain derived from cardiovascular magnetic resonance, as well as clinical features such as laboratory tests, electrocardiograms, and echocardiography. Meanwhile, we innovatively integrated cardiac motion characteristics through deep learning algorithms and fast neural convolution networks to construct deep learning heart failure prediction model. The results showed that compared with the traditional cox model, the deep learning model had higher efficacy for prognosis evaluation in patients with heart failure and could provide risk stratification in patients with heart failure, which may further guide clinical decision-making.