Article
Clinical Neurology
Jan J. A. van den Dorpel, Marjolein H. G. Dremmen, Nadine A. M. E. van der Beek, Dimitris Rizopoulos, Pieter A. van Doorn, Ans T. van der Ploeg, Ryan L. Muetzel, Johanna M. P. van den Hout
Summary: Enzyme replacement therapy has greatly improved the prognosis of patients with Pompe disease. Classic infantile patients show progressive white matter abnormalities, while the brain involvement in late-onset patients is still not well understood. This study used structural and diffusion tensor imaging (DTI) to examine the microstructure of white matter in classic infantile and late-onset Pompe patients. The results showed significant differences in FA and MD between classic infantile patients and a reference population, with large-association fibers being most affected. Late-onset patients did not show deviations from normal neurodevelopment. These findings suggest that DTI can be a promising tool for monitoring therapy response in Pompe patients.
JOURNAL OF NEUROLOGY
(2023)
Article
Neurosciences
Graham Little, Christian Beaulieu
Summary: A new automatic cortical boundary segmentation method was developed to work directly on native DTI images, which showed reasonable segmentations for all individuals and large proportions were within +/- 1mm from conventional approach. FA and MD were relatively stable across the cortex, with some focal regions showing higher FA.
Article
Radiology, Nuclear Medicine & Medical Imaging
Xin Wang, Lei Luo, Jianming Xing, Jianliang Wang, Bimin Shi, Yin-Min Li, Yong-Gang Li
Summary: The study demonstrated that DTI is effective in evaluating the diagnostic accuracy of diabetic peripheral neuropathy and can effectively differentiate between axonal injury and demyelination, showing correlations with electrophysiology parameters.
QUANTITATIVE IMAGING IN MEDICINE AND SURGERY
(2022)
Article
Mathematical & Computational Biology
Song Xu, Xufeng Yao, Liting Han, Yuting Lv, Xixi Bu, Gan Huang, Yifeng Fan, Tonggang Yu, Gang Huang
Summary: The study utilized a graph-based diffusion tensor imaging network approach to investigate the changes in brain aging, revealing significant differences in network characteristics between young adults and older adults on a whole-brain level.
MATHEMATICAL BIOSCIENCES AND ENGINEERING
(2021)
Article
Geochemistry & Geophysics
A. T. Krzyzak, W. Mazur, A. Fheed, W. P. Weglarz
Summary: This study explores the application of diffusion tensor imaging (DTI) in the characterization of rock core samples, demonstrating its potential in studying the pore space characteristics through analysis of DT parameters and visualization results. The introduction of a new parameter, principal diffusion tracts, provides additional information to understand the microgeometry of the sample's pore network. The study also showcases the potential applications of DTI in determining pore size distribution, tortuosity, and conductivity.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Engineering, Biomedical
Shuhei Shibukawa, Tetsu Niwa, Tosiaki Miyati, Tetsuo Ogino, Daisuke Yoshimaru, Kagayaki Kuroda
Summary: In this study, the application of second-order motion compensation diffusion tensor imaging (2nd-MC DTI) with fractional anisotropy (FA) processing was found to reduce the impact of pulsation on CSF temperature measurements, improving the accuracy of intracranial CSF temperature determination.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Biomedical
Shaonan Liu, Yuanyuan Liu, Xi Xu, Rui Chen, Dong Liang, Qiyu Jin, Hui Liu, Guoqing Chen, Yanjie Zhu
Summary: In this study, a deep learning framework called FG-Net was developed to generate high-quality DTI parameter maps from six DWIs. Compared to previous fast DTI studies, FG-Net improves estimation accuracy by generating inter-directional DWIs to supplement loss information. Evaluation results demonstrated that FG-Net can generate accurate parameter maps with less than 5% quantification error. FG-Net outperformed conventional tensor fitting and black-box network fitting in both qualitative and quantitative metrics.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Clinical Neurology
C. A. de Planque, J. M. G. Florisson, R. C. Tasker, B. F. M. Rijken, M. L. C. van Veelen, I. M. J. Mathijssen, M. H. Lequin, M. H. G. Dremmen
Summary: This study aimed to compare white matter tract diffusivity values in non-operated syndromic craniosynostosis patients aged 0-2 years with healthy controls. The results indicated that age and frontal occipital horn ratio significantly influenced radial diffusivity.
Article
Acoustics
R. Corroenne, D. Grevent, H. Mahallati, G. Gauchard, L. Bussieres, Y. Ville, L. J. Salomon
Summary: This study aimed to evaluate the feasibility of DTI of the spinal cord in utero and examine gestational-age-related changes in DTI parameters. The results showed that DTI of the spinal cord is feasible in normal fetuses and there is a significant GA-related change in FA in the fetal spinal cord during pregnancy.
ULTRASOUND IN OBSTETRICS & GYNECOLOGY
(2023)
Article
Multidisciplinary Sciences
Ye-Ryoung Lee, Dong-Young Kim, Yonghyeon Jo, Moonseok Kim, Wonshik Choi
Summary: This study presents a volumetric image reconstruction framework that combines the wavelength and propagation angles of light waves to better deal with multiple scattering. By simultaneously scanning the wavelength and illumination angle of the light source, the use of signal waves is increased 32-fold compared to existing 2D-based methods, achieving ultrahigh volumetric resolution even within complex scattering medium.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Biomedical
Mehdi Sadighi, Mert Sisman, Berk C. Acikgoz, Hasan H. Eroglu, B. Murat Eyuboglu
Summary: DT-MREIT is an imaging modality based on diffusion tensor imaging and MREIT techniques, allowing for the reconstruction of low-frequency anisotropic conductivity distribution. A novel reconstruction algorithm is proposed in this study to reconstruct conductivity tensor images using a single current injection, increasing clinical applicability. The method is evaluated using simulated measurements and physical experiments, demonstrating successful reconstruction of anisotropic conductivity distribution.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Computer Science, Artificial Intelligence
Alexis Reymbaut, Alex Valcourt Caron, Guillaume Gilbert, Filip Szczepankiewicz, Markus Nilsson, Simon K. Warfield, Maxime Descoteaux, Benoit Scherrer
Summary: Diffusion tensor imaging provides increased sensitivity to microstructural tissue changes compared to conventional anatomical imaging, but presents limited specificity. To address this issue, the DIAMOND model subdivides voxel content into diffusion compartments and estimates compartmental non-central matrix-variate Gamma distributions of diffusion tensors. Incorporating tensor-valued diffusion encoding, the Magic DIAMOND model demonstrates improved accuracy in estimating brain microstructural features, particularly in regions of fiber crossing.
MEDICAL IMAGE ANALYSIS
(2021)
Article
Neurosciences
Jennifer J. Muller, Ruixuan Wang, Devon Milddleton, Mahdi Alizadeh, Ki Chang Kang, Ryan Hryczyk, George Zabrecky, Chloe Hriso, Emily Navarreto, Nancy Wintering, Anthony J. Bazzan, Chengyuan Wu, Daniel A. Monti, Xun Jiao, Qianhong Wu, Andrew B. Newberg, Feroze B. Mohamed
Summary: This study analyzed the ability of data-driven analysis of diffusion tensor imaging (DTI) and neurite orientation dispersion imaging (NODDI) to develop biomarkers for symptom severity inference. Compared with conventional T1-weighted imaging, machine learning-based models achieved significantly better results with accuracies ranging from 58.7% to 73.0% for DTI and 64.0% to 72.3% for NODDI.
FRONTIERS IN NEUROSCIENCE
(2023)
Article
Geriatrics & Gerontology
Chun Yen Kok, Christine Lock, Ting Yao Ang, Nicole C. Keong
Summary: The study demonstrates that the semi-automated pseudo-atlas DTI tractography method is reliable and reproducible across different cohorts, generating the majority of fiber tracts. Although there are significant differences in DTI metrics obtained from both methods, the white matter injury patterns produced are consistent with literature findings.
FRONTIERS IN AGING NEUROSCIENCE
(2022)
Article
Medicine, General & Internal
Liu He, Gao Dan, Sun Yuanbo, Tang Fengqiong, Hu Mingcheng, Li Hongyi
Summary: This study evaluated the diagnostic value of DTI-GBMRI in identifying renal histopathology and renal efficiency in CKD patients. The results showed that DTI-GBMRI had higher accuracy and sensitivity in assessing renal function and renal damage compared to DTI-MRI.
Article
Biochemical Research Methods
Rafael N. Henriques, Marco Palombo, Sune N. Jespersen, Noam Shemesh, Henrik Lundell, Andrada Ianus
Summary: Diffusion Magnetic Resonance Imaging (dMRI) is a crucial non-invasive technique for probing tissue structure, with double diffusion encoding (DDE) being an advanced method that provides specific diffusion correlations information and is versatile for different applications. DDE measurements can help improve biophysical models, study intra-cellular diffusion, and enhance contrast in preclinical and clinical settings.
JOURNAL OF NEUROSCIENCE METHODS
(2021)
Article
Neurosciences
Erhard Trillingsgaard Naess-Schmidt, Jakob Udby Blicher, Mille Moller Thastum, Charlotte Ulrikka Rask, Susanne Wulff Svendsen, Andreas Schroder, Astrid Hogh Tuborgh, Leif ostergaard, Ryan Sangill, Torben Lund, Sune Norhoj Jespersen, Asger Roer Pedersen, Brian Hansen, Simon Fristed Eskildsen, Jorgen Feldbaek Nielsen
Summary: A recent study found that a novel behavioral intervention is more effective in reducing symptoms in young patients with long-term post-concussion symptoms compared to enhanced usual care. However, diffusion-weighted MRI indices responded differently to the interventions, and their correlation with the improvement of post-concussion symptoms remains unclear.
JOURNAL OF NEUROSCIENCE RESEARCH
(2021)
Article
Multidisciplinary Sciences
Christian Thaler, Anna A. Kyselyova, Tobias D. Faizy, Marie T. Nawka, Sune Jespersen, Brian Hansen, Jan-Patrick Stellmann, Christoph Heesen, Klarissa H. Stuerner, Maria Stark, Jens Fiehler, Maxim Bester, Susanne Gellissen
Summary: In this study, mean kurtosis (MK) values showed differences among different types of lesions, providing predictive value for distinguishing between them, while mean diffusivity (MD) values did not show significant differences between lesions. Therefore, MK may be a useful parameter in assessing tissue microstructure damage in neurological disorders.
Article
Radiology, Nuclear Medicine & Medical Imaging
Rafael N. Henriques, Sune N. Jespersen, Derek K. Jones, Jelle Veraart
Summary: The study introduces a novel DKI estimator that improves the robustness and reproducibility of kurtosis metrics by using a robust scalar kurtosis index, resulting in parameter maps with enhanced quality and contrast. This new DKI estimator promotes wider use of DKI in clinical research and diagnostics by enhancing the reproducibility and precision of DKI fitting, enabling enhanced visual, quantitative, and statistical analyses of DKI parameters.
MAGNETIC RESONANCE IN MEDICINE
(2021)
Article
Neurosciences
Jonas L. Olesen, Leif ostergaard, Noam Shemesh, Sune N. Jespersen
Summary: This study reevaluates the assumptions of the standard diffusion model by collecting comprehensive MRI data and proposes three model extensions to address the issues identified. The analysis identifies a three-compartment description as the optimal model, with the third compartment exhibiting slow diffusion and a minor signal fraction. Failure to consider the presence of this compartment can severely misguide inferences about white matter microstructure.
Article
Neurosciences
Rita Alves, Rafael Neto Henriques, Leevi Kerkela, Cristina Chavarrias, Sune N. Jespersen, Noam Shemesh
Summary: Noninvasively detecting and characterizing modulations in cellular scale micro-architecture remains a pressing need in contemporary neuroimaging. Diffusion MRI (dMRI) and Diffusion Kurtosis Imaging (DKI) have shown enhanced sensitivity in stroke detection. Using Correlation Tensor MRI (CTI) to investigate the underpinnings of kurtosis measurements in acute ischemic lesions has provided specific signatures for different kurtosis sources, such as neurite beading and cell swelling. In vivo experiments have demonstrated the stability and relevance of these findings in stroke imaging, suggesting potential for addressing current limitations and understanding pathophysiological correlates.
Article
Neurosciences
Jonas L. Olesen, Leif Ostergaard, Noam Shemesh, Sune N. Jespersen
Summary: This article discusses the characterization of neural tissue microstructure and the issue of specificity of dMRI signals, as well as experimental validation of biophysical models for white and gray matter cells.
Article
Radiology, Nuclear Medicine & Medical Imaging
Jonas L. Olesen, Andrada Ianus, Leif Ostergaard, Noam Shemesh, Sune N. Jespersen
Summary: This study investigates a denoising strategy using redundancy in high-dimensional data. By comparing matrix-based MPPCA with tensor-based MPPCA, it is found that tensor MPPCA achieves better denoising performance, especially for small data patches.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Editorial Material
Biophysics
Sune Norhoj Jespersen
NMR IN BIOMEDICINE
(2022)
Article
Biophysics
Anders Dyhr Sandgaard, Noam Shemesh, Valerij G. Kiselev, Sune Norhoj Jespersen
Summary: The magnetic susceptibility of tissue provides information about its chemical composition and microstructural organization, but the relationship between magnetic microstructure and the measurable Larmor frequency shift is only understood for a few idealized cases. In this study, we analyzed the microstructure formed by magnetized, NMR-invisible infinite cylinders in an NMR-reporting fluid. We examined various geometries of mesoscopic Lorentz cavities and inclusions through simulations, and found that the cavity size should be approximately one order of magnitude larger than the width of the inclusions. We also derived the Larmor frequency shift for a population of cylinders with arbitrary orientation dispersion and found that it depends on the Laplace expansion coefficients p2m of the cylinders' orientation distribution function. Our work emphasizes the importance of considering microstructural organization when estimating magnetic tissue properties.
NMR IN BIOMEDICINE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Anders Dyhr Sandgaard, Noam Shemesh, Sune Norhoj Jespersen, Valerij G. Kiselev
Summary: Estimating magnetic susceptibility using MRI relies on inverting the relationship between susceptibility and measured Larmor frequency. This study tests the impact of accounting for the constraint that Larmor frequency is only measured inside the sample and susceptibility sources should only reside inside the same sample.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Neurosciences
Francisca F. Fernandes, Jonas L. Olesen, Sune N. Jespersen, Noam Shemesh
Summary: MP-PCA denoising is a popular method for denoising MRI data, but in rodent fMRI, thermal noise from coils can affect activation mapping accuracy and violate MP-PCA assumptions. In this study, we developed a method to denoise vendor data in rodent fMRI and evaluated the effects of MP-PCA denoising on activation spreading. Our results showed that MP-PCA denoising improved SNR and Fourier Spectral Amplitude, but also caused activation spreading and smoother functional maps. The optimal denoising window for improved specificity depends on the data's tSNR and functional CNR.
Article
Radiology, Nuclear Medicine & Medical Imaging
Anders Dyhr Sandgaard, Valerij G. Kiselev, Rafael Neto Henriques, Noam Shemesh, Sune Norhoj Jespersen
Summary: This study aims to extend quantitative susceptibility mapping to consider the microstructure of white matter and demonstrate its effect on ex vivo mouse brain at 16.4T. The results show that the new model improves susceptibility estimation and the application of susceptibility tensor imaging produces highly anisotropic susceptibility tensors. For ex vivo mouse brain, the omega Meso due to white matter microstructure has a substantial impact on susceptibility, changing up to 25% of root-mean-squared-difference.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Nichlas Vous Christensen, Michael Vaeggemose, Nikolaj Bogh, Esben S. S. Hansen, Jonas L. Olesen, Yaewon Kim, Daniel B. Vigneron, Jeremy W. Gordon, Sune N. Jespersen, Christoffer Laustsen
Summary: In this study, a novel denoising method was compared to the current state-of-the-art denoising method, and it was found that the new method performed slightly better in noise removal. The results showed that this new method is widely applicable to different data sources and is the preferred denoising method for x-nuclei imaging improvements.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Meeting Abstract
Oncology
C. Skinnerup Byskov, L. Haldbo-Classen, A. Harboll, S. Norhoj Jespersen, J. Folsted Kallehauge
RADIOTHERAPY AND ONCOLOGY
(2021)