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DT-MRI muscle

Shantanu Sinha, Usha Sinha, Vadim Malis, Valmik Bhargava, Kyoko Sakamoto, Mahadevan Rajasekaran
BACKGROUND: Urinary incontinence is a major clinical problem arising primarily from age-related degenerative changes to the sphincter muscles. However, the precise anatomy of the normal male sphincter muscles has yet to be established. Diffusion tensor imaging (DTI) may offer a unique insight into muscle microstructure and fiber architecture. PURPOSE: To explore the anatomy of the urethral sphincter muscles pertinent to urinary continence function using DT-MRI. STUDY TYPE: Prospective cohort study...
March 23, 2018: Journal of Magnetic Resonance Imaging: JMRI
Francesca Trojsi, Pierpaolo Sorrentino, Giuseppe Sorrentino, Gioacchino Tedeschi
Brain imaging techniques, especially those based on magnetic resonance imaging (MRI) and magnetoencephalography (MEG), have been increasingly applied to study multiple large-scale distributed brain networks in healthy people and neurological patients. With regard to neurodegenerative disorders, amyotrophic lateral sclerosis (ALS), clinically characterized by the predominant loss of motor neurons and progressive weakness of voluntary muscles, and frontotemporal lobar degeneration (FTLD), the second most common early-onset dementia, have been proven to share several clinical, neuropathological, genetic, and neuroimaging features...
October 27, 2017: CNS Spectrums
Saurav Z K Sajib, Nitish Katoch, Hyung Joong Kim, Oh In Kwon, Eung Je Woo
OBJECTIVE: Low-frequency conductivity and current density imaging using MRI includes magnetic resonance electrical impedance tomography (MREIT), diffusion tensor MREIT (DT-MREIT), conductivity tensor imaging (CTI), and magnetic resonance current density imaging (MRCDI). MRCDI and MREIT provide current density and isotropic conductivity images, respectively, using current-injection phase MRI techniques. DT-MREIT produces anisotropic conductivity tensor images by incorporating diffusion weighted MRI into MREIT...
2017: IEEE Transactions on Bio-medical Engineering
David B Berry, Shangting You, John Warner, Lawrence R Frank, Shaochen Chen, Samuel R Ward
The ability to noninvasively assess skeletal muscle microstructure, which predicts function and disease, would be of significant clinical value. One method that holds this promise is diffusion tensor magnetic resonance imaging (DT-MRI), which is sensitive to the microscopic diffusion of water within tissues and has become ubiquitous in neuroimaging as a way of assessing neuronal structure and damage. However, its application to the assessment of changes in muscle microstructure associated with injury, pathology, or age remains poorly defined, because it is difficult to precisely control muscle microstructural features in vivo...
September 2017: Tissue Engineering. Part A
Jos Oudeman, Valentina Mazzoli, Marco A Marra, Klaas Nicolay, Mario Maas, Nico Verdonschot, Andre M Sprengers, Aart J Nederveen, Gustav J Strijkers, Martijn Froeling
Musculoskeletal (dys-)function relies for a large part on muscle architecture which can be obtained using Diffusion-Tensor MRI (DT-MRI) and fiber tractography. However, reconstructed tracts often continue along the tendon or aponeurosis when using conventional methods, thus overestimating fascicle lengths. In this study, we propose a new method for semiautomatic segmentation of tendinous tissue using tract density (TD). We investigated the feasibility and repeatability of this method to quantify the mean fascicle length per muscle...
December 2016: Physiological Reports
Valentina Mazzoli, Jos Oudeman, Klaas Nicolay, Mario Maas, Nico Verdonschot, Andre M Sprengers, Aart J Nederveen, Martijn Froeling, Gustav J Strijkers
In this study we investigated the changes in fiber length and diffusion parameters as a consequence of passive lengthening and stretching of the calf muscles. We hypothesized that changes in radial diffusivity (RD) are caused by changes in the muscle fiber cross sectional area (CSA) as a consequence of lengthening and shortening of the muscle. Diffusion Tensor MRI (DT-MRI) measurements were made twice in five healthy volunteers, with the foot in three different positions (30° plantarflexion, neutral position and 15° dorsiflexion)...
December 2016: NMR in Biomedicine
Bruce M Damon, Martijn Froeling, Amanda K W Buck, Jos Oudeman, Zhaohua Ding, Aart J Nederveen, Emily C Bush, Gustav J Strijkers
The mechanical functions of muscles involve the generation of force and the actuation of movement by shortening or lengthening under load. These functions are influenced, in part, by the internal arrangement of muscle fibers with respect to the muscle's mechanical line of action. This property is known as muscle architecture. In this review, we describe the use of diffusion tensor (DT)-MRI muscle fiber tracking for the study of muscle architecture. In the first section, the importance of skeletal muscle architecture to function is discussed...
March 2017: NMR in Biomedicine
Judith M Sieben, Ilse van Otten, Arno Lataster, Martijn Froeling, Aart J Nederveen, Gustav J Strijkers, Maarten R Drost
STUDY DESIGN: Diffusion tensor magnetic resonance imaging (DT-MRI) reconstruction of lumbar erector spinae (ES) compared with cadaver dissection. OBJECTIVE: The aim of this study was to reconstruct the human lumbar ES from in vivo DT-MRI measurements and to compare the results with literature and cadaver dissection. SUMMARY OF BACKGROUND DATA: DT-MRI enables 3-dimensional in vivo reconstruction of muscle architecture. Insight in ES architecture may improve the understanding of low back function...
April 2016: Clinical Spine Surgery
Amanda K W Buck, Zhaohua Ding, Christopher P Elder, Theodore F Towse, Bruce M Damon
PURPOSE: To assess the effect of anisotropic smoothing on fiber tracking measures, including pennation angle, fiber tract length, and fiber tract number in the medial gastrocnemius (MG) muscle in healthy subjects using diffusion-weighted magnetic resonance imaging (DW-MRI). MATERIALS AND METHODS: 3T DW-MRI data were used for muscle fiber tractography in the MG of healthy subjects. Anisotropic smoothing was applied at three levels (5%, 10%, 15%), and pennation angle, tract length, fiber tract number, fractional anisotropy, and principal eigenvector orientation were quantified for each smoothing level...
2015: PloS One
Judith M Sieben, Ilse van Otten, Arno Lataster, Martijn Froeling, Aart J Nederveen, Gustav J Strijkers, Maarten R Drost
STUDY DESIGN: Diffusion Tensor MRI (DT-MRI) reconstruction of lumbar erector spinae (ES) compared to cadaver dissection. OBJECTIVE: Aim of this study was to reconstruct the human lumbar ES from in vivo DT-MRI measurements and to compare the results with literature and cadaver dissection. SUMMARY OF BACKGROUND DATA: DT-MRI enables three-dimensional in vivo reconstruction of muscle architecture. Insight in ES architecture may improve understanding of low back function...
October 16, 2013: Journal of Spinal Disorders & Techniques
Sarah E Williams, Anneriet M Heemskerk, E Brian Welch, Ke Li, Bruce M Damon, Jane H Park
PURPOSE: To determine the minimum water percentage in a muscle region of interest that would allow diffusion tensor (DT-) MRI data to reflect the diffusion properties of pure muscle accurately. MATERIALS AND METHODS: Proton density-weighted images with and without fat saturation were obtained at the mid-thigh in four subjects. Co-registered DT-MR images were used to calculate the diffusion tensor's eigenvalues and fractional anisotropy. RESULTS: The eigenvalues transitioned monotonically as a function of water signal percentage from values near to those expected for pure fat to those for pure muscle...
November 2013: Journal of Magnetic Resonance Imaging: JMRI
Naomi M Cermak, Michael D Noseworthy, Jacqueline M Bourgeois, Mark A Tarnopolsky, Martin J Gibala
INTRODUCTION: Structural evidence of exercise-induced muscle disruption has traditionally involved histological analysis of muscle tissue obtained by needle biopsy, however, there are multiple limitations with this technique. Recently, diffusion tensor magnetic resonance imaging (DT-MRI) has been successfully demonstrated to noninvasively assess skeletal muscle abnormalities induced by traumatic injury. METHODS: To determine the potential for DT-MRI to detect musculoskeletal changes after a bout of eccentric exercise, 10 healthy men performed 300 eccentric actions on an isokinetic dynamometer...
July 2012: Muscle & Nerve
Bruce M Damon, Anneriet M Heemskerk, Zhaohua Ding
Fiber curvature is a functionally significant muscle structural property, but its estimation from diffusion-tensor magnetic resonance imaging fiber tracking data may be confounded by noise. The purpose of this study was to investigate the use of polynomial fitting of fiber tracts for improving the accuracy and precision of fiber curvature (κ) measurements. Simulated image data sets were created in order to provide data with known values for κ and pennation angle (θ). Simulations were designed to test the effects of increasing inherent fiber curvature (3...
June 2012: Magnetic Resonance Imaging
Michael J Thrippleton, Mark E Bastin, Kirsty I Munro, Alistair R Williams, Anca Oniscu, Maurits A Jansen, Gavin D Merrifield, Graham McKillop, David E Newby, Scott I Semple, Ian Marshall, Hilary O Critchley
PURPOSE: To investigate the water diffusion tensor properties of ex vivo tissue in the fibroid uterus, including the influence of degeneration, and the relevance of the principal eigenvector orientation to the underlying tissue structure. MATERIALS AND METHODS: Following hysterectomy, high-resolution structural T(2) -weighted and diffusion tensor magnetic resonance imaging (DT-MRI) were performed on nine uteri at 7 T. Mean diffusivity (MD), fractional anisotropy (FA), and principal eigenvector orientation were measured in myometrium and in myxoid and dense tissue in fibroids...
December 2011: Journal of Magnetic Resonance Imaging: JMRI
Manku Rana, James M Wakeling
Muscle architecture is an important parameter affecting the muscle function. Most of the previous studies on in-vivo muscle architecture have used in 2D ultrasound. The importance of the third dimension has not been much explored due to lack of appropriate methods. DT-MRI has been used to study muscle architecture in 3D, however, due to long scan times of about 15 min DT-MRI has not been suitable to study active muscle contractions. The purpose of this study was to develop and validate methods to determine in-vivo muscle fascicle orientations in 3D using ultrasound...
July 28, 2011: Journal of Biomechanics
Natalie Chandler, Oleg Aslanidi, David Buckley, Shin Inada, Steven Birchall, Andrew Atkinson, Danielle Kirk, Oliver Monfredi, Peter Molenaar, Robert Anderson, Vinod Sharma, Daniel Sigg, Henggui Zhang, Mark Boyett, Halina Dobrzynski
We have previously shown in rabbit that the pacemaker of the heart (the sinus node) is widespread and matches the wide distribution of the leading pacemaker site within the right atrium. There is, however, uncertainty about the precise location of the pacemaker in human heart, and its spatial relationships with the surrounding right atrial muscle. Therefore, the aim of the current study was to investigate the distribution of the sinus node tissue in a series of healthy human hearts and, for one of the hearts to construct a computer three-dimensional anatomical model of the sinus node, including the likely orientation of myocytes...
June 2011: Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
Rodrigo de Luis-García, Carl-Fredrik Westin, Carlos Alberola-López
In this paper, we introduce a new approach for tensor field segmentation based on the definition of mixtures of Gaussians on tensors as a statistical model. Working over the well-known Geodesic Active Regions segmentation framework, this scheme presents several interesting advantages. First, it yields a more flexible model than the use of a single Gaussian distribution, which enables the method to better adapt to the complexity of the data. Second, it can work directly on tensor-valued images or, through a parallel scheme that processes independently the intensity and the local structure tensor, on scalar textured images...
January 2011: Computerized Medical Imaging and Graphics: the Official Journal of the Computerized Medical Imaging Society
Song Zhang, J Allen Crow, Xiaoyong Yang, Joseph Chen, Ali Borazjani, Katie B Mullins, Wei Chen, Robert C Cooper, Ronald M McLaughlin, Jun Liao
Evaluation of structural parameters following a myocardial infarction (MI) is important to assess left ventricular function and remodeling. In this study, we assessed the capability of 3D diffusion tensor magnetic resonance imaging (DT-MRI) to assess tissue degeneration shortly after an MI using a porcine model of infarction. Two days after an induced infarction, hearts were explanted and immediately scanned by a 3T MRI scanner with a diffusion tensor imaging protocol. 3D fiber tracks and clustering models were generated from the diffusion-weighted imaging data...
October 2010: Annals of Biomedical Engineering
Nadja Saupe, Lawrence M White, Jeffrey Stainsby, George Tomlinson, Marshall S Sussman
OBJECTIVE: The aim of our study was to determine the optimal b value for 1.5-T diffusion tensor (DT) MRI and fiber tractography of in vivo human skeletal muscle. SUBJECTS AND METHODS: Five healthy volunteers were included in this prospective study. DT MRI of the proximal calf was performed with 15 directions of diffusion sensitization and parallel imaging with an acceleration factor of 2. Each single-shot spin-echo echo-planar imaging sequence was performed in each volunteer with eight b values ranging from 125 s/mm(2) to 1,000 s/mm(2)...
June 2009: AJR. American Journal of Roentgenology
J Herman Kan, Anneriet M Heemskerk, Zhaohua Ding, Andrew Gregory, Gregory Mencio, Kurt Spindler, Bruce M Damon
PURPOSE: To determine the feasibility of using diffusion tensor MRI (DT-MRI) -based muscle fiber tracking to create biomechanical models of the quadriceps mechanism in healthy subjects and those with chronic lateral patellar dislocation (LPD). MATERIALS AND METHODS: Four healthy (average 14.5 years old; BMI 21.8) and four chronic LPD (average 17.3 years old; BMI 22.4) females underwent DT and axial T1W MRI of the thighs. The anatomical and physiologic cross-sectional areas (ACSA and PCSA, respectively) and pennation angle were calculated of the vastus lateralis oblique (VLO) and vastus medialis oblique (VMO) muscles...
March 2009: Journal of Magnetic Resonance Imaging: JMRI
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