-
On the correction of spiral trajectories on a preclinical MRI scanner with a high‐performance gradient insert NMR Biomed. (IF 2.7) Pub Date : 2024-09-13 Hannah Scholten, Tobias Wech, Sascha Köhler, Sean S. Smart, Jordan H. Boyle, Irvin Teh, Herbert Köstler, Jürgen E. Schneider
This study aimed to examine different trajectory correction methods for spiral imaging on a preclinical scanner with high‐performance gradients with respect to image quality in a phantom and in vivo. The gold standard method of measuring the trajectories in a separate experiment is compared to an isotropic delay‐correction, a correction using the gradient system transfer function (GSTF), and a combination
-
The added value of diffusion tensor imaging with systematic bias correction for the assessment of liver morphology and physiology NMR Biomed. (IF 2.7) Pub Date : 2024-09-11 Weronika Mazur‐Rosmus, William M. Spees, Artur T. Krzyżak
Diffusion‐weighted images of the human liver are prone to artifacts from bulk motions, poor SNR, non‐uniformity of magnetic field gradients, and non‐optimal choice of diffusion weightings. These factors markedly affect diffusion tensor imaging (DTI) metrics such as mean diffusivity (MD) and fractional anisotropy (FA).This work presents a simple preprocessing pipeline for enhanced magnetic field gradient
-
Issue Information NMR Biomed. (IF 2.7) Pub Date : 2024-09-10
No abstract is available for this article.
-
The impact of isoflurane anesthesia on brain metabolism in mice: An MRI and electroencephalography study NMR Biomed. (IF 2.7) Pub Date : 2024-09-10 Zhiliang Wei, Seung‐Eon Roh, Xiuli Yang, Wenshen Wang, Jiekang Wang, Lin Chen, Yuguo Li, Adnan Bibic, Hanzhang Lu
Isoflurane is one of the most widely used anesthetic agents in rodent imaging studies. However, the impact of isoflurane on brain metabolism has not been fully characterized to date, primarily due to a scarcity of noninvasive technologies to quantitatively measure the brain's metabolic rate in vivo. In this study, using noncontrast MRI techniques, we dynamically measured cerebral metabolic rate of
-
Measurement of blood–brain barrier water exchange rate using diffusion‐prepared and multi‐echo arterial spin labelling: Comparison of quantitative values and age dependence NMR Biomed. (IF 2.7) Pub Date : 2024-09-10 Catherine A. Morgan, David L. Thomas, Xingfeng Shao, Amnah Mahroo, Tabitha J. Manson, Vinod Suresh, Deidre Jansson, Yolanda Ohene, Matthias Günther, Danny J. J. Wang, Lynette J. Tippett, Michael Dragunow
Water exchange rate (Kw) across the blood–brain barrier (BBB) is an important physiological parameter that may provide new insight into ageing and neurodegenerative disease. Recently, two non‐invasive arterial spin labelling (ASL) MRI methods have been developed to measure Kw, but results from the different methods have not been directly compared. Furthermore, the association of Kw with age for each
-
Scientists' perspectives on ethical issues in research with emerging portable neuroimaging technology: The need for guidance on ethical, legal, and societal implications (ELSI) NMR Biomed. (IF 2.7) Pub Date : 2024-09-09 Frances Daniels, Efraín Torres, Frances Lawrenz, Susan M. Wolf, Francis X. Shen
Deployment of new, more portable, and less costly neuroimaging technologies such as portable magnetoencephalography, electroencephalography, positron emission tomography, functional near‐infrared spectroscopy, high‐density diffuse optical tomography, and magnetic resonance imaging is advancing rapidly. Given this trajectory toward increasing use of neuroimaging outside the hospital, we sought to identify
-
Comparison of compartmental analytical Blood‐Oxygen‐Level‐Dependent functional Magnetic Resonance Imaging models against Monte Carlo simulations performed over cortical micro‐angiograms NMR Biomed. (IF 2.7) Pub Date : 2024-09-09 Jordan Charest, Mathieu Walsh, Élie Genois, Emmanuelle Sévigny, Pierre‐Olivier Schwarz, Louis Gagnon, Michèle Desjardins
Blood oxygen level‐dependent functional magnetic resonance imaging (BOLD fMRI) arises from a physiological and physical cascade of events taking place at the level of the cortical microvasculature which constitutes a medium with complex geometry. Several analytical models of the BOLD contrast have been developed, but these have not been compared directly against detailed bottom‐up modeling methods
-
A motion assessment method for reference stack selection in fetal brain MRI reconstruction based on tensor rank approximation NMR Biomed. (IF 2.7) Pub Date : 2024-09-05 Haoan Xu, Wen Shi, Jiwei Sun, Tianshu Zheng, Xinyi Xu, Cong Sun, Sun Yi, Guangbin Wang, Dan Wu
Slice‐to‐volume registration and super‐resolution reconstruction are commonly used to generate 3D volumes of the fetal brain from 2D stacks of slices acquired in multiple orientations. A critical initial step in this pipeline is to select one stack with the minimum motion among all input stacks as a reference for registration. An accurate and unbiased motion assessment (MA) is thus crucial for successful
-
Identifying biochemical changes in the kidney using proton nuclear magnetic resonance in an adenine diet chronic kidney disease mouse model NMR Biomed. (IF 2.7) Pub Date : 2024-09-04 Tyrone L. R. Humphries, Glenda C. Gobe, Aaron J. Urquhart, Robert J. Ellis, Graham J. Galloway, David A. Vesey, Ross S. Francis
This study aimed to investigate the metabolic changes in the kidneys in a murine adenine–diet model of chronic kidney disease (CKD). Kidney fibrosis is the common pathological manifestation across CKD aetiologies. Sustained inflammation and fibrosis cause changes in preferred energy metabolic pathways in the cells of the kidney. Kidney cortical tissue from mice receiving a control or adenine‐supplemented
-
Repeatability of alkaline inorganic phosphate quantification in the skeletal muscle using 31P‐magnetic resonance spectroscopy at 3 T NMR Biomed. (IF 2.7) Pub Date : 2024-09-03 Alexs A. Matias, Corinna F. Serviente, Stephen T. Decker, Muhammet Enes Erol, Gaia Giuriato, Yann Le Fur, Rajakumar Nagarajan, David Bendahan, Gwenael Layec
The detection of a secondary inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (31P‐MRS), poses technical challenges at 3 Tesla (T). Overcoming these challenges is imperative for the integration of this biomarker into clinical research. To evaluate the repeatability and reliability of measuring resting skeletal muscle
-
Brain tumor classification for combining the advantages of multilayer dense net‐based feature extraction and hyper‐parameters tuned attentive dual residual generative adversarial network classifier using wild horse optimization NMR Biomed. (IF 2.7) Pub Date : 2024-08-29 Shenbagarajan Anantharajan, Shenbagalakshmi Gunasekaran, J. Angela Jennifa Sujana
In this manuscript, attentive dual residual generative adversarial network optimized using wild horse optimization algorithm for brain tumor detection (ADRGAN‐WHOA‐BTD) is proposed. Here, the input imageries are gathered using BraTS, RemBRANDT, and Figshare datasets. Initially, the images are preprocessed to increase the quality of images and eliminate the unwanted noises. The preprocessing is performed
-
Quantitative ultrashort echo time MR imaging of knee osteochondral junction: An ex vivo feasibility study NMR Biomed. (IF 2.7) Pub Date : 2024-08-28 Jiyo S. Athertya, Arya Suprana, James Lo, Alecio F. Lombardi, Dina Moazamian, Eric Y. Chang, Jiang Du, Yajun Ma
Compositional changes can occur in the osteochondral junction (OCJ) during the early stages and progressive disease evolution of knee osteoarthritis (OA). However, conventional magnetic resonance imaging (MRI) sequences are not able to image these regions efficiently because of the OCJ region's rapid signal decay. The development of new sequences able to image and quantify OCJ region is therefore highly
-
Diffusion MRI in prostate cancer with ultra‐strong whole‐body gradients NMR Biomed. (IF 2.7) Pub Date : 2024-08-28 Malwina Molendowska, Marco Palombo, Kieran G. Foley, Krishna Narahari, Fabrizio Fasano, Derek K. Jones, Daniel C. Alexander, Eleftheria Panagiotaki, Chantal M. W. Tax
Diffusion‐weighted MRI (dMRI) is universally recommended for the detection and classification of prostate cancer (PCa), with PI‐RADS recommendations to acquire b‐values of ≥1.4 ms/μm2. However, clinical dMRI suffers from a low signal‐to‐noise ratio (SNR) as the consequence of prolonged echo times (TEs) attributable to the limited gradient power in the range of 40–80 mT/m. To overcome this, MRI systems
-
Imaging arterial and venous vessels using Iron Dextran enhanced multi‐echo 3D gradient echo MRI at 7T NMR Biomed. (IF 2.7) Pub Date : 2024-08-27 Yinghao Li, Wei Li, Adrian Paez, Di Cao, Yuanqi Sun, Chunming Gu, Kaihua Zhang, Xinyuan Miao, Peiying Liu, Wenbo Li, Jay Pillai, Hanzhang Lu, Peter C. M. van Zijl, Christopher Earley, Xu Li, Jun Hua
Iron Dextran is a widely used iron oxide compound to treat iron‐deficiency anemia patients in the clinic. Similar to other iron oxide compounds such as Ferumoxytol, it can also be used off‐label as an intravascular magnetic resonance imaging (MRI) contrast agent due to its strong iron‐induced T2 and T2* shortening effects. In this study, we seek to evaluate the feasibility of using Iron Dextran enhanced
-
Linear Bloch–Siegert phase‐encoded low‐field MRI: RF coils, pulse sequence, and image reconstruction NMR Biomed. (IF 2.7) Pub Date : 2024-08-27 Sai Abitha Srinivas, Jonathan B. Martin, Christopher E. Vaughn, William A. Grissom
Conventional gradient systems have several weaknesses including high cost and bulk. As a step towards addressing these while providing new degrees of freedom for spatial encoding and system design in Magnetic Resonance Imaging (MRI), a radio frequency (RF) gradient encoding system and pulse sequence for phase encoding using the Bloch–Siegert (BS) shift were developed. Optimized BS spatial encoding
-
Evidence for biexponential glutamate T2 relaxation in human visual cortex at 3T: A functional MRS study NMR Biomed. (IF 2.7) Pub Date : 2024-08-27 Polina Emeliyanova, Laura M. Parkes, Stephen R. Williams, Caroline Lea‐Carnall
Functional magnetic resonance spectroscopy (fMRS) measures dynamic changes in metabolite concentration in response to neural stimulation. The biophysical basis of these changes remains unclear. One hypothesis suggests that an increase or decrease in the glutamate signal detected by fMRS could be due to neurotransmitter movements between cellular compartments with different T2 relaxation times. Previous
-
Free‐breathing time‐resolved 4D MRI with improved T1‐weighting contrast NMR Biomed. (IF 2.7) Pub Date : 2024-08-26 Jingjia Chen, Ding Xia, Chenchan Huang, Krishna Shanbhogue, Hersh Chandarana, Li Feng
This work proposes MP‐Grasp4D (magnetization‐prepared golden‐angle radial sparse parallel 4D) MRI, a free‐breathing, inversion recovery (IR)‐prepared, time‐resolved 4D MRI technique with improved T1‐weighted contrast. MP‐Grasp4D MRI acquisition incorporates IR preparation into a radial gradient echo sequence. MP‐Grasp4D employs a golden‐angle navi‐stack‐of‐stars sampling scheme, where imaging data
-
Sensitivity analysis of models of gas exchange for lung hyperpolarised 129Xe MR NMR Biomed. (IF 2.7) Pub Date : 2024-08-26 Yohn Taylor, Frederick J. Wilson, Mina Kim, Geoff J. M. Parker
Sensitivity analysis enables the identification of influential parameters and the optimisation of model composition. Such methods have not previously been applied systematically to models describing hyperpolarised 129Xe gas exchange in the lung. Here, we evaluate the current 129Xe gas exchange models to assess their precision for identifying alterations in pulmonary vascular function and lung microstructure
-
Toward structure and metabolism of glycogen C1‐C6 in humans at 7 T by localized 13C MRS using low‐power bilevel broadband 1H decoupling NMR Biomed. (IF 2.7) Pub Date : 2024-08-22 Eulalia Serés Roig
This work aims to develop and implement a pulse‐acquire sequence for three‐dimensional (3D) single‐voxel localized 13C MRS in humans at 7 T, in conjunction with bilevel broadband 1H decoupling, and to test its feasibility in vitro and in vivo in human calf muscle with emphasis on the detection of glycogen C1‐C6. A localization scheme suitable for measuring fast‐relaxing 13C signals in humans at 7 T
-
Feasibility of 3D MRI fingerprinting for rapid knee cartilage T1, T2, and T1ρ mapping at 0.55T: Comparison with 3T NMR Biomed. (IF 2.7) Pub Date : 2024-08-22 Hector L. De Moura, Anmol Monga, Xiaoxia Zhang, Marcelo V. W. Zibetti, Mahesh B. Keerthivasan, Ravinder R. Regatte
Low‐field strength scanners present an opportunity for more inclusive imaging exams and bring several challenges including lower signal‐to‐noise ratio (SNR) and longer scan times. Magnetic resonance fingerprinting (MRF) is a rapid quantitative multiparametric method that can enable multiple quantitative maps simultaneously. To demonstrate the feasibility of an MRF sequence for knee cartilage evaluation
-
Reducing thermal noise in high‐resolution quantitative magnetic resonance imaging rotating frame relaxation mapping of the human brain at 3 T NMR Biomed. (IF 2.7) Pub Date : 2024-08-22 Sara Ponticorvo, Antonietta Canna, Steen Moeller, Mehmet Akcakaya, Gregory J. Metzger, Pavel Filip, Lynn E. Eberly, Shalom Michaeli, Silvia Mangia
Quantitative maps of rotating frame relaxation (RFR) time constants are sensitive and useful magnetic resonance imaging tools with which to evaluate tissue integrity in vivo. However, to date, only moderate image resolutions of 1.6 x 1.6 x 3.6 mm3 have been used for whole‐brain coverage RFR mapping in humans at 3 T. For more precise morphometrical examinations, higher spatial resolutions are desirable
-
Brain volume and microglial density changes are correlated in a juvenile mouse model of cranial radiation and CSF1R inhibitor treatment NMR Biomed. (IF 2.7) Pub Date : 2024-08-21 Ramy Ayoub, Sabrina Yang, Helen Ji, Lloyd Fan, Steven De Michino, Donald J. Mabbott, Brian J. Nieman
Microglia have been shown to proliferate and become activated following cranial radiotherapy (CRT), resulting in a chronic inflammatory response. We investigated the role of microglia in contributing to widespread volume losses observed in the brain following CRT in juvenile mice. To manipulate microglia, we used low‐dose treatment with a highly selective CSF1R inhibitor called PLX5622 (PLX). We hypothesized
-
Ensemble learning‐based pretreatment MRI radiomic model for distinguishing intracranial extraventricular ependymoma from glioblastoma multiforme NMR Biomed. (IF 2.7) Pub Date : 2024-08-21 Haoling He, Qianyan Long, Liyan Li, Yan Fu, Xueying Wang, Yuhong Qin, Muliang Jiang, Zeming Tan, Xiaoping Yi, Bihong T. Chen
This study aims to develop an ensemble learning (EL) method based on magnetic resonance (MR) radiomic features to preoperatively differentiate intracranial extraventricular ependymoma (IEE) from glioblastoma (GBM). This retrospective study enrolled patients with histopathologically confirmed IEE and GBM from June 2016 to June 2021. Radiomics features were extracted from T1‐weighted imaging (T1WI) and
-
Significant age‐related differences between lower leg muscles of older and younger female subjects detected by ultrashort echo time magnetization transfer modeling NMR Biomed. (IF 2.7) Pub Date : 2024-08-19 Saeed Jerban, Hamidreza Shaterian Mohammadi, Jiyo S. Athertya, Amir Masoud Afsahi, Niloofar Shojaeiadib, Dina Moazamian, Samuel R. Ward, Gina Woods, Christine B. Chung, Jiang Du, Eric Y. Chang
Magnetization transfer (MT) magnetic resonance imaging (MRI) can be used to estimate the fraction of water and macromolecular proton pools in tissues. MT modeling paired with ultrashort echo time acquisition (UTE‐MT modeling) has been proposed to improve the evaluation of the myotendinous junction and fibrosis in muscle tissues, which the latter increases with aging. This study aimed to determine if
-
Novel spin‐lock time sampling strategies for improved reproducibility in quantitative T1ρ mapping NMR Biomed. (IF 2.7) Pub Date : 2024-08-17 Sandeep Panwar Jogi, Qi Peng, Ramin Jafari, Ricardo Otazo, Can Wu
This study aimed to optimize the sampling of spin‐lock times (TSLs) in quantitative T1ρ mapping for improved reproducibility. Two new TSL sampling schemes were proposed: (i) reproducibility‐guided random sampling (RRS) and (ii) reproducibility‐guided optimal sampling (ROS). They were compared to the existing linear sampling (LS) and precision‐guided sampling (PS) schemes for T1ρ reproducibility through
-
Improvements in precision and accuracy of complex‐ relative to real‐domain linear combination model spectral fitting not necessarily recovered by zero filling NMR Biomed. (IF 2.7) Pub Date : 2024-08-14 Leonardo Campos, Kelley M. Swanberg, Martin Gajdošík, Karl Landheer, Christoph Juchem
Although the information obtained from in vivo proton magnetic resonance spectroscopy (1H MRS) presents a complex‐valued spectrum, spectral quantification generally employs linear combination model (LCM) fitting using the real spectrum alone. There is currently no known investigation comparing fit results obtained from LCM fitting over the full complex data versus the real data and how these results
-
CEST effect of dimethyl sulfoxide at negative offset frequency NMR Biomed. (IF 2.7) Pub Date : 2024-08-13 Haoyun Su, Lok Hin Law, Yang Liu, Jianpan Huang, Kannie W. Y. Chan
Dimethyl sulfoxide (DMSO) has wide biomedical applications such as cryoprotectant and hydrophobic drug carrier. Here, we report for the first time that DMSO can generate a distinctive chemical exchange saturation transfer (CEST) signal at around −2 ppm. Structural analogs of DMSO, including aprotic and protic solvents, also demonstrated CEST signals from −1.4 to −3.8 ppm. When CEST detectable barbituric
-
Automatic deep learning segmentation of the hippocampus on high‐resolution diffusion magnetic resonance imaging and its application to the healthy lifespan NMR Biomed. (IF 2.7) Pub Date : 2024-08-13 Dylan Miller, Cory Efird, Kevin Grant Solar, Christian Beaulieu, Dana Cobzas
Diffusion tensor imaging (DTI) can provide unique contrast and insight into microstructural changes with age or disease of the hippocampus, although it is difficult to measure the hippocampus because of its comparatively small size, location, and shape. This has been markedly improved by the advent of a clinically feasible 1‐mm isotropic resolution 6‐min DTI protocol at 3 T of the hippocampus with
-
Unfolding coil localized errors from an imperfect slice profile using a structured autocalibration matrix: An application to reduce outflow effects in cine bSSFP imaging NMR Biomed. (IF 2.7) Pub Date : 2024-08-08 Fadil Ali, Zhaohuan Zhang, Andres Saucedo, Ajin Joy, Vahid Ghodrati, Kim‐Lien Nguyen, J. Paul Finn, Mark Bydder
PurposeBalanced steady‐state free precession (bSSFP) imaging is susceptible to outflow effects where excited spins leaving the slice as part of the blood stream are misprojected back onto the imaging plane. Previous work proposed using slice‐encoding steps to localize these outflow effects from corrupting the target slice, at the expense of prolonged scan time. This present study extends this idea
-
Tracking gonadal development in fish: An in vivo MRI study on polar cod, Boreogadus saida (Lepechin, 1774) NMR Biomed. (IF 2.7) Pub Date : 2024-08-08 Nicole Vogt, Felizitas C. Wermter, Jasmine Nahrgang, Daniela Storch, Christian Bock
Magnetic resonance imaging (MRI) was applied to determine the sex of polar cod (Boreogadus saida Lepechin, 1774) (Actinopterygii: Gadidae) and to follow the gonadal development in individual animals over time. Individual unanaesthetised fish were transferred to a measurement chamber inside a preclinical 9.4 T MRI scanner and continuously perfused with aerated seawater. A screening procedure at an average
-
Synthesis of higher‐B0 CEST Z‐spectra from lower‐B0 data via deep learning and singular value decomposition NMR Biomed. (IF 2.7) Pub Date : 2024-08-08 Mengdi Yan, Chongxue Bie, Wentao Jia, Chuyu Liu, Xiaowei He, Xiaolei Song
Chemical exchange saturation transfer (CEST) MRI at 3 T suffers from low specificity due to overlapping CEST effects from multiple metabolites, while higher field strengths (B0) allow for better separation of Z‐spectral “peaks,” aiding signal interpretation and quantification. However, data acquisition at higher B0 is restricted by equipment access, field inhomogeneity and safety issues. Herein, we
-
Arterial input function estimation compensating for inflow and partial voluming in dynamic contrast‐enhanced MRI NMR Biomed. (IF 2.7) Pub Date : 2024-08-07 Chih‐Hsien Tseng, Martijn A. Nagtegaal, Matthias J.P. van Osch, Jaap Jaspers, Alejandra Mendez Romero, Piotr Wielopolski, Marion Smits, Frans M. Vos
Both inflow and the partial volume effect (PVE) are sources of error when measuring the arterial input function (AIF) in dynamic contrast‐enhanced (DCE) MRI. This is relevant, as errors in the AIF can propagate into pharmacokinetic parameter estimations from the DCE data. A method was introduced for flow correction by estimating and compensating the number of the perceived pulse of spins during inflow
-
Issue Information NMR Biomed. (IF 2.7) Pub Date : 2024-08-06
No abstract is available for this article.
-
Velocity of cerebrospinal fluid in the aqueduct measured by phase‐contrast MRI in rat NMR Biomed. (IF 2.7) Pub Date : 2024-08-06 Guangliang Ding, Lian Li, Michael Chopp, Li Zhang, Qingjiang Li, Hao Luo, Min Wei, Jing Zhang, Edward Boyd, Zhenggang Zhang, Quan Jiang
Cerebrospinal fluid (CSF) circulation plays a key role in cerebral waste clearance via the glymphatic system. Although CSF flow velocity is an essential component of CSF dynamics, it has not been sufficiently characterized, and particularly, in studies of the glymphatic system in rat. To investigate the relationship between the flow velocity of CSF in the brain aqueduct and the glymphatic waste clearance
-
Simultaneous whole‐liver water T1$$ {\mathrm{T}}_1 $$ and T2$$ {\mathrm{T}}_2 $$ mapping with isotropic resolution during free‐breathing NMR Biomed. (IF 2.7) Pub Date : 2024-08-05 Jonathan Stelter, Kilian Weiss, Lisa Steinhelfer, Veronika Spieker, Elizabeth Huaroc Moquillaza, Weitong Zhang, Marcus R. Makowski, Julia A. Schnabel, Bernhard Kainz, Rickmer F. Braren, Dimitrios C. Karampinos
PurposeTo develop and validate a data acquisition scheme combined with a motion‐resolved reconstruction and dictionary‐matching‐based parameter estimation to enable free‐breathing isotropic resolution self‐navigated whole‐liver simultaneous water‐specific () and () mapping for the characterization of diffuse and oncological liver diseases.MethodsThe proposed data acquisition consists of a magnetization
-
Diffusion model based on generalized map for accelerated MRI NMR Biomed. (IF 2.7) Pub Date : 2024-08-05 Zengwei Xiao, Yujuan Lu, Binzhong He, Pinhuang Tan, Shanshan Wang, Xiaoling Xu, Qiegen Liu
In recent years, diffusion models have made significant progress in accelerating magnetic resonance imaging. Nevertheless, it still has inherent limitations, such as prolonged iteration times and sluggish convergence rates. In this work, we present a novel generalized map generation model based on mean‐reverting SDE, called GM‐SDE, to alleviate these shortcomings. Notably, the core idea of GM‐SDE is
-
Automatic pipeline for segmentation of LV myocardium on quantitative MR T1 maps using deep learning model and computation of radial T1 and ECV values NMR Biomed. (IF 2.7) Pub Date : 2024-08-04 Raufiya Jafari, Ankit Kandpal, Radhakrishan Verma, Vinayak Aggarwal, Rakesh Kumar Gupta, Anup Singh
Native T1 mapping is a non‐invasive technique used for early detection of diffused myocardial abnormalities, and it provides baseline tissue characterization. Post‐contrast T1 mapping enhances tissue differentiation, enables extracellular volume (ECV) calculation, and improves myocardial viability assessment. Accurate and precise segmenting of the left ventricular (LV) myocardium on T1 maps is crucial
-
T1 relaxation and axon fibre configuration in human white matter NMR Biomed. (IF 2.7) Pub Date : 2024-08-04 Grace Hutchinson, Jeromy Thotland, Pramod K. Pisharady, Michael Garwood, Christophe Lenglet, Risto A. Kauppinen
Understanding the effects of white matter (WM) axon fibre microstructure on T1 relaxation is important for neuroimaging. Here, we have studied the interrelationship between T1 and axon fibre configurations at 3T and 7T. T1 and S0 (=signal intensity at zero TI) were computed from MP2RAGE images acquired with six inversion recovery times. Multishell diffusion MRI images were analysed for fractional anisotropy
-
Very‐long T2‐weighted imaging of the non‐lesional brain tissue in multiple sclerosis patients NMR Biomed. (IF 2.7) Pub Date : 2024-08-01 Pietro Bontempi, Sabrina Marangoni, Lucia Cazzoletti, Albulena Bajrami, Bruno Giometto, Paolo Farace, Umberto Rozzanigo
The purpose of this study is to demonstrate that T2‐weighted imaging with very long echo time (TE > 300 ms) can provide relevant information in neurodegenerative/inflammatory disorder. Twenty patients affected by relapsing–remitting multiple sclerosis with stable disease course underwent 1.5 T 3D FLAIR, 3D T1‐weighted, and a multi‐echo sequence with 32 echoes (TE = 10–320 ms). Focal lesions (FL) were
-
Improvement of MRS at ultra‐high field using a wireless RF array NMR Biomed. (IF 2.7) Pub Date : 2024-07-31 Andrew Frankini, Gaurav Verma, Alan C. Seifert, Bradley N. Delman, Varun Subramaniam, Priti Balchandani, Akbar Alipour
We aim to assess a straightforward technique to enhance spectral quality in the brain, particularly in the cerebellum, during 7 T MRI scans. This is achieved through a wireless RF array insert designed to mitigate signal dropouts caused by the limited transmit field efficiency in the inferior part of the brain. We recently developed a wireless RF array to improve MRI and 1H‐MRS at 7 T by augmenting
-
The effect of fat model variation on muscle fat fraction quantification in a cross‐sectional cohort NMR Biomed. (IF 2.7) Pub Date : 2024-07-30 Martijn Froeling, Linda Heskamp
Spectroscopic imaging, rooted in Dixon's two‐echo spin sequence to distinguish water and fat, has evolved significantly in acquisition and processing. Yet precise fat quantification remains a persistent challenge in ongoing research. With adequate phase characterization and correction, the fat composition models will impact measurements of fatty tissue. However, the effect of the used fat model in
-
Medial prefrontal cortex neurotransmitter abnormalities in posttraumatic stress disorder with and without comorbidity to major depression NMR Biomed. (IF 2.7) Pub Date : 2024-07-26 Kelley M. Swanberg, Hetty Prinsen, Christopher L. Averill, Leonardo Campos, Abhinav V. Kurada, John H. Krystal, Ismene L. Petrakis, Lynnette A. Averill, Douglas L. Rothman, Chadi G. Abdallah, Christoph Juchem
Posttraumatic stress disorder (PTSD) is a chronic psychiatric condition that follows exposure to a traumatic stressor. Though previous in vivo proton (1H) MRS) research conducted at 4 T or lower has identified alterations in glutamate metabolism associated with PTSD predisposition and/or progression, no prior investigations have been conducted at higher field strength. In addition, earlier studies
-
Automatic removal of large blood vasculature for objective assessment of brain tumors using quantitative dynamic contrast‐enhanced magnetic resonance imaging NMR Biomed. (IF 2.7) Pub Date : 2024-07-25 Anshika Kesari, Virendra Kumar Yadav, Rakesh Kumar Gupta, Anup Singh
The presence of a normal large blood vessel (LBV) in a tumor region can impact the evaluation of quantitative dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) parameters and tumor classification. Hence, there is a need for automatic removal of LBVs from brain tissues including intratumoral regions for achieving an objective assessment of tumors. This retrospective study included 103 histopathologically
-
Considerations for event‐related gamma‐aminobutyric acid functional magnetic resonance spectroscopy NMR Biomed. (IF 2.7) Pub Date : 2024-07-25 Paul G. Mullins
The use of sequential proton magnetic resonance spectroscopy (MRS) to follow glutamate and gamma‐aminobutyric acid (GABA) changes during functional task‐based paradigms, functional MRS (fMRS), has increased. This technique has been used to investigate GABA dynamics during both sensory and behavioural tasks, usually with long ‘block design’ paradigms. Recently, there has been an increase in interest
-
Noise‐reduction techniques for 1H‐FID‐MRSI at 14.1 T: Monte Carlo validation and in vivo application NMR Biomed. (IF 2.7) Pub Date : 2024-07-23 Brayan Alves, Dunja Simicic, Jessie Mosso, Thanh Phong Lê, Guillaume Briand, Wolfgang Bogner, Bernard Lanz, Bernhard Strasser, Antoine Klauser, Cristina Cudalbu
Proton magnetic resonance spectroscopic imaging (1H‐MRSI) is a powerful tool that enables the multidimensional non‐invasive mapping of the neurochemical profile at high resolution over the entire brain. The constant demand for higher spatial resolution in 1H‐MRSI has led to increased interest in post‐processing‐based denoising methods aimed at reducing noise variance. The aim of the present study was
-
Ultra‐low‐field magnetic resonance angiography at 0.05 T: A preliminary study NMR Biomed. (IF 2.7) Pub Date : 2024-07-20 Shi Su, Jiahao Hu, Ye Ding, Junhao Zhang, Vick Lau, Yujiao Zhao, Ed X. Wu
We aim to explore the feasibility of head and neck time‐of‐flight (TOF) magnetic resonance angiography (MRA) at ultra‐low‐field (ULF). TOF MRA was conducted on a highly simplified 0.05 T MRI scanner with no radiofrequency (RF) and magnetic shielding. A flow‐compensated three‐dimensional (3D) gradient echo (GRE) sequence with a tilt‐optimized nonsaturated excitation RF pulse, and a flow‐compensated
-
Probing diffusion of water and metabolites to assess white matter microstructure in Duchenne muscular dystrophy NMR Biomed. (IF 2.7) Pub Date : 2024-07-15 Rosanne Govaarts, Nathalie Doorenweerd, Chloé F. Najac, Emma M. Broek, Maud E. Tamsma, Kieren G. Hollingsworth, Erik H. Niks, Itamar Ronen, Volker Straub, Hermien E. Kan
Duchenne muscular dystrophy (DMD) is a progressive X‐linked neuromuscular disorder caused by the absence of functional dystrophin protein. In addition to muscle, dystrophin is expressed in the brain in both neurons and glial cells. Previous studies have shown altered white matter microstructure in patients with DMD using diffusion tensor imaging (DTI). However, DTI measures the diffusion properties
-
How to accurately quantify brain magnetic susceptibility in the context of Parkinson's disease: Validation on phantoms and healthy volunteers at 1.5 and 3 T NMR Biomed. (IF 2.7) Pub Date : 2024-07-12 Aurélien Hervouin, Johanne Bézy‐Wendling, Fanny Noury
Currently, brain iron content represents a new neuromarker for understanding the physiopathological mechanisms leading to Parkinson's disease (PD). In vivo quantification of biological iron is possible by reconstructing magnetic susceptibility maps obtained using quantitative susceptibility mapping (QSM). Applying QSM is challenging, as up to now, no standardization of acquisition protocols and phase
-
Sequence comparison of spoiled gradient echo and balanced steady‐state free precession for pulmonary free‐breathing proton MRI in patients and healthy volunteers: Correspondence, repeatability, and validation with dynamic contrast‐enhanced MRI NMR Biomed. (IF 2.7) Pub Date : 2024-07-12 Jonah J. Hahn, Andreas Voskrebenzev, Lea Behrendt, Filip Klimeš, Gesa H. Pöhler, Frank Wacker, Jens Vogel‐Claussen
Phase‐resolved functional lung (PREFUL) MRI is a proton‐based, contrast agent‐free technique derived from the Fourier decomposition approach to measure regional ventilation and perfusion dynamics during free‐breathing. Besides the necessity of extensive PREFUL postprocessing, the utilized MRI sequence must fulfill specific requirements. This study investigates the impact of sequence selection on PREFUL‐MRI–derived
-
Hyperpolarized 13C and 31P MRS detects differences in cardiac energetics, metabolism, and function in obesity, and responses following treatment NMR Biomed. (IF 2.7) Pub Date : 2024-07-12 Andrew J. M. Lewis, Michael S. Dodd, Joevin Sourdon, Craig A. Lygate, Kieran Clarke, Stefan Neubauer, Damian J. Tyler, Oliver J. Rider
Obesity is associated with important changes in cardiac energetics and function, and an increased risk of adverse cardiovascular outcomes. Multi‐nuclear MRS and MRI techniques have the potential to provide a comprehensive non‐invasive assessment of cardiac metabolic perturbation in obesity. A rat model of obesity was created by high‐fat diet feeding. This model was characterized using in vivo hyperpolarized
-
Ultrashort echo time magnetic resonance elastography for quantification of the mechanical properties of short T2 tissues via optimal control‐based radiofrequency pulses NMR Biomed. (IF 2.7) Pub Date : 2024-07-12 Pilar Sango‐Solanas, Kevin Tse Ve Koon, Eric Van Reeth, Stéphane Nicolle, Jean‐François Palierne, Cyrielle Caussy, Olivier Beuf
The aim of the current study is to demonstrate the feasibility of radiofrequency (RF) pulses generated via an optimal control (OC) algorithm to perform magnetic resonance elastography (MRE) and quantify the mechanical properties of materials with very short transverse relaxation times (T2 < 5 ms) for the first time. OC theory applied to MRE provides RF pulses that bring isochromats from the equilibrium
-
Issue Information NMR Biomed. (IF 2.7) Pub Date : 2024-07-10
No abstract is available for this article.
-
Cover Image NMR Biomed. (IF 2.7) Pub Date : 2024-07-10 Rohith Saai Pemmasani Prabakaran, Se Weon Park, Joseph H. C. Lai, Kexin Wang, Jiadi Xu, Zilin Chen, Abdul‐mojeed Olabisi Ilyas, Huabing Liu, Jianpan Huang, Kannie W. Y. Chan
-
Prospective longitudinal cohort study of quantitative muscle magnetic resonance imaging in a healthy control population NMR Biomed. (IF 2.7) Pub Date : 2024-07-10 Johannes Forsting, Robert Rehmann, Marlena Rohm, Abdulhadi Kocabas, Alice De Lorenzo, Anne‐Katrin Güttsches, Matthias Vorgerd, Martijn Froeling, Lara Schlaffke
Quantitative muscle magnetic resonance imaging (qMRI) is a valuable methodology for assessing muscular injuries and neuromuscular disorders. Notably, muscle diffusion tensor imaging (DTI) gives insights into muscle microstructural and macrostructural characteristics. However, the long‐term reproducibility and robustness of these measurements remain relatively unexplored. The purpose of this prospective
-
High‐resolution magic angle spinning nuclear magnetic resonance of donor pancreatic tissue may predict islet viability prior to isolation NMR Biomed. (IF 2.7) Pub Date : 2024-07-09 Carolyn M. Slupsky, Brian D. Sykes, Jonathan R. T. Lakey
For patients with type 1 diabetes mellitus complicated by severe hypoglycemia, clinical islet transplantation is an efficacious alternative to whole pancreas transplantation. While islet transplantation has improved over the last few years, there remain questions regarding its cost‐effectiveness and donor allosensitization, which is exacerbated when islets from more than one donor are required. Understanding
-
The impact of diffusion tensor imaging tractography settings on muscle fascicle architecture and diffusion parameter estimates: Tract length, completion, and curvature are most sensitive to tractography settings NMR Biomed. (IF 2.7) Pub Date : 2024-07-05 Carly A. Lockard, Melissa T. Hooijmans, Xingyu Zhou, Crystal Coolbaugh, Bruce M. Damon
Diffusion‐tensor (DT)‐MRI tractography provides information about properties relevant to muscle health and function, including estimates of architectural properties such as fascicle length, pennation angle, and curvature and diffusion properties such as mean diffusivity (MD) and fractional anisotropy (FA). Tractography settings, including integration algorithms, thresholds for early tract termination
-
Tuned exchange imaging: Can the filter exchange imaging pulse sequence be adapted for applications with thin slices and restricted diffusion? NMR Biomed. (IF 2.7) Pub Date : 2024-07-04 Samo Lasič, Arthur Chakwizira, Henrik Lundell, Carl‐Fredrik Westin, Markus Nilsson
Filter exchange imaging (FEXI) is a double diffusion‐encoding (DDE) sequence that is specifically sensitive to exchange between sites with different apparent diffusivities. FEXI uses a diffusion‐encoding filtering block followed by a detection block at varying mixing times to map the exchange rate. Long mixing times enhance the sensitivity to exchange, but they pose challenges for imaging applications
-
Filter‐exchange spectroscopy is sensitive to gradual cell membrane degradation NMR Biomed. (IF 2.7) Pub Date : 2024-07-02 Athanasia Kaika, Geoffrey J. Topping, Luca Nagel, Franz Schilling
Transmembrane water permeability changes occur after initialization of necrosis and are a mechanism for early detection of cell death. Filter‐exchange spectroscopy (FEXSY) is sensitive to transmembrane water permeability and enables its quantification by magnetic resonance via the apparent exchange rate (AXR). In this study, we investigate AXR changes during necrotic cell death. FEXSY measurements
-
Comparison of baseline correction algorithms for in vivo 1H‐MRS NMR Biomed. (IF 2.7) Pub Date : 2024-07-02 Diego Pasmiño, Johannes Slotboom, Brigitte Schweisthal, Pamela Guevara, Waldo Valenzuela, Esteban J. Pino
Proton MRS is used clinically to collect localized, quantitative metabolic data from living tissues. However, the presence of baselines in the spectra complicates accurate MRS data quantification. The occurrence of baselines is not specific to short‐echo‐time MRS data. In short‐echo‐time MRS, the baseline consists typically of a dominating macromolecular (MM) part, and can, depending on B0 shimming
-
Quantification of the rotating frame relaxation time T2ρ: Comparison of balanced spin‐lock and continuous‐wave Malcolm‐Levitt preparations NMR Biomed. (IF 2.7) Pub Date : 2024-06-24 Maximilian Gram, Martin Christa, Fabian Tobias Gutjahr, Petra Albertova, Tatjana Williams, Peter Michael Jakob, Wolfgang Rudolf Bauer, Peter Nordbeck
For the quantification of rotating frame relaxation times, the T2ρ relaxation pathway plays an essential role. Nevertheless, T2ρ imaging has been studied only to a small extent compared with T1ρ, and preparation techniques for T2ρ have so far been adapted from T1ρ methods. In this work, two different preparation concepts are compared specifically for the use of T2ρ mapping. The first approach involves