Progressive Supranuclear Palsy and Diffusion Tensor Imaging

2009 ◽  
Vol 4 (2) ◽  
pp. 108 ◽  
Author(s):  
Shoichi Ito ◽  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Progressive Supranuclear Palsy ◽  
Diffusion Tensor ◽  
Anterior Part ◽  
Internal Capsule ◽  
Neural Systems ◽  
Cerebellar Peduncles ◽  
Magnetic Resonance Imaging Mri ◽  
And Diffusion ◽  
Diffusion Properties

Progressive supranuclear palsy (PSP) is a neurodegenerative disease affecting multiple neural systems, particularly the extrapyramidal system. Early differentiation of PSP from other diseases mainly featuring parkinsonism, such as Parkinson's disease and multiple system atrophy, is necessary because the therapeutic strategy and outcome are substantially different. Diffusion tensor imaging is a recently developed magnetic resonance imaging (MRI) sequence that is able to non-invasively evaluate neural tracts. Two approaches may be used to measure diffusion properties. One approach is to measure diffusion properties by setting the regions of interest on circular/square regions or along the tractography. The other approach is to perform voxel-by-voxel analysis of the diffusion properties. There are several reports evaluating diffusion tensor abnormalities in PSP, and regions with diffusion tensor abnormlities are distributed through frontal projection fibres, the anterior part of the corpus callosum, superior longitudinal fasciculus, arcuate fasciculus, posterior thalamic radiations, internal capsule and superior cerebellar peduncles. Here, diffusion tensor studies in PSP are reviewed and clinical applications, limitations and future perspectives of diffusion tensor analysis in PSP are discussed.

Pitfalls in Diffusion-Weighted and Diffusion Tensor Imaging of the Pediatric Brain

2017 ◽  
Vol 48 (05) ◽  
pp. 340-349 ◽  
Author(s):  
Nivedita Agarwal ◽  
Aylin Tekes ◽  
Andrea Poretti ◽  
Avner Meoded ◽  
Thierry Huisman
Keyword(s):  
Diffusion Tensor Imaging ◽  
Diffusion Tensor ◽  
Wide Spectrum ◽  
Qualitative Evaluation ◽  
Basic Knowledge ◽  
Brain Diseases ◽  
Water Molecules ◽  
Diffusion Weighted ◽  
Magnetic Resonance Imaging Mri ◽  
And Diffusion

AbstractDiffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) are advanced magnetic resonance imaging (MRI) techniques that are based on differences in the diffusion rate of water molecules in brain tissue. DWI and DTI are widely used in pediatric neuroradiology to evaluate a wide spectrum of brain diseases. The interpretation of DWI and DTI images requires a basic knowledge of the underlying physics to detect potential pitfalls and avoid misinterpretation. Several DWI pitfalls are related to the dependency of DWI images not only on the diffusivity of water molecules, but also on various additional MRI phenomena such as the T1- and T2- relaxation characteristics and MRI-related artifacts. In addition, knowledge about the age of the child and interval between the onset of injury and acquisition of DWI/DTI images is important. Finally, qualitative evaluation (“eye-balling”) maybe misleading, and the application of quantitative measurements of DTI scalars may avoid misdiagnosis.

scholarly journals Tractography-based targeting of ventral intermediate nucleus: A comparison between conventional stereotactic targeting and diffusion tensor imaging-based targeting

2021 ◽  
Author(s):  
Anupa A. Vijayakumari ◽  
Drew Parker ◽  
Andrew I Yang ◽  
Ashwin G. Ramayya ◽  
Ronald L. Wolf ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Focused Ultrasound ◽  
Diffusion Tensor ◽  
Lateral Position ◽  
Individual Variability ◽  
Probabilistic Tracking ◽  
Ventral Intermediate Nucleus ◽  
Magnetic Resonance Imaging Mri ◽  
And Diffusion ◽  
Deep Brain

AbstractBackgroundThe ventral intermediate (VIM) nucleus of the thalamus is the main target for lesioning using magnetic resonance imaging (MRI) guided focused ultrasound (MRgFUS) or deep brain stimulation (DBS). Targeting of VIM still depends on standard stereotactic coordinates, which do not account for inter-individual variability. Several approaches have been proposed including visualization of dentato-rubro-thalamic tract (DRTT) using diffusion tensor imaging tractography.ObjectiveTo compare probabilistic tracking of DRTT with deterministic tracking of DRTT and stereotactic coordinates to identify the most appropriate approach to target VIM.MethodsIn this retrospective study, we assessed the VIM targeted using stereotactic coordinates, deterministic and probabilistic tracking of DRTT in 19 patients with essential tremor who underwent DBS with VIM targeted using microelectrode recordings. We subsequently determined the positions of VIM derived from these three approaches and compared with that of DBS lead position using paired sample t-tests.ResultsThe probabilistic tracking of DRTT was significantly anterior to the lead (1.45 ± 1.61 mm (P< 0.0001)), but not in the medial/lateral position (−0.29±2.42 mm (P=0.50)). Deterministic tracking of DRTT was significantly lateral (2.16 ± 1.94 mm (P< 0.0001)) and anterior to the lead (1.66 ± 2.1 mm (P< 0.0001)). The stereotactic coordinates were significantly lateral (2.41 ± 1.41 mm (P< 0.0001)) and anterior (1.23 ± 0.89 mm (P< 0.0001)) to the lead.ConclusionProbabilistic tracking of DRTT was found to be superior in targeting VIM compared to deterministic tracking and stereotactic coordinates.

scholarly journals Meyer’s Loop Anatomy Demonstrated Using Diffusion Tensor MR Imaging and Fiber Tractography at 3T

2014 ◽  
Vol 60 (5) ◽  
pp. 215-222 ◽  
Author(s):  
Cristina Goga ◽  
Zeynep Firat ◽  
Klara Brinzaniuc ◽  
Is Florian
Keyword(s):  
Diffusion Tensor Imaging ◽  
Diffusion Tensor ◽  
Region Of Interest ◽  
Fiber Tractography ◽  
Brain Images ◽  
3 Dimensional ◽  
Software Release ◽  
Magnetic Resonance Imaging Mri ◽  
Meyer’S Loop

Abstract Objective: The ultimate anatomy of the Meyer’s loop continues to elude us. Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) may be able to demonstrate, in vivo, the anatomy of the complex network of white matter fibers surrounding the Meyer’s loop and the optic radiations. This study aims at exploring the anatomy of the Meyer’s loop by using DTI and fiber tractography. Methods: Ten healthy subjects underwent magnetic resonance imaging (MRI) with DTI at 3 T. Using a region-of-interest (ROI) based diffusion tensor imaging and fiber tracking software (Release 2.6, Achieva, Philips), sequential ROI were placed to reconstruct visual fibers and neighboring projection fibers involved in the formation of Meyer’s loop. The 3-dimensional (3D) reconstructed fibers were visualized by superimposition on 3-planar MRI brain images to enhance their precise anatomical localization and relationship with other anatomical structures. Results: Several projection fiber including the optic radiation, occipitopontine/parietopontine fibers and posterior thalamic peduncle participated in the formation of Meyer’s loop. Two patterns of angulation of the Meyer’s loop were found. Conclusions: DTI with DTT provides a complimentary, in vivo, method to study the details of the anatomy of the Meyer’s loop.

170 Myelination and Diffusion Tensor Imaging Findings in Mild Traumatic Brain Injury

Neurosurgery ◽  
2013 ◽  
Vol 60 ◽  
pp. 176-177
Author(s):  
Heather Spader ◽  
Anna Ellermeier ◽  
Lindsay Walker ◽  
Jeffrey Rogg ◽  
Rees Cosgrove ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Diffusion Tensor Imaging ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Diffusion Tensor ◽  
Imaging Findings ◽  
And Diffusion

scholarly journals Pontine Tegmental Cap Dysplasia: MR Imaging and Diffusion Tensor Imaging Features of Impaired Axonal Navigation

2008 ◽  
Vol 30 (1) ◽  
pp. 113-119 ◽  
Author(s):  
P. Jissendi-Tchofo ◽  
D. Doherty ◽  
G. McGillivray ◽  
R. Hevner ◽  
D. Shaw ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Mr Imaging ◽  
Diffusion Tensor ◽  
Imaging Features ◽  
And Diffusion

Increased muscle fiber fractional anisotropy value using diffusion tensor imaging after compression without fiber injury

2021 ◽  
pp. 028418512110582
Author(s):  
Takumi Yokohama ◽  
Motoyuki Iwasaki ◽  
Daisuke Oura ◽  
Sho Furuya ◽  
Yoshimasa Niiya
Keyword(s):  
Diffusion Tensor Imaging ◽  
Fractional Anisotropy ◽  
Muscle Tissue ◽  
Diffusion Tensor ◽  
Longitudinal Direction ◽  
Diffusion Parameters ◽  
Apparent Diffusion ◽  
The Mean ◽  
Magnetic Resonance Imaging Mri ◽  
Age Range

Background Recent studies have indicated that injuries such as muscle tears modify the microstructural integrity of muscle, leading to substantial alterations in measured diffusion parameters. Therefore, the fractional anisotropy (FA) value decreases. However, we hypothesized that soft tissue, such as muscle tissue, undergoes reversible changes under conditions of compression without fiber injury. Purpose To evaluate the FA change due to compression in muscle tissue without fiber injury. Material and Methods Diffusion tensor imaging (DTI) was performed on both feet of 10 healthy volunteers (mean age = 35.0 ± 10.39 years; age range = 23–52 years) using a 3.0-T magnetic resonance imaging (MRI) scanner with an eight-channel phased array knee coil. An MRI-compatible sphygmomanometer was applied to the individuals’ lower legs and individuals were placed in a compressed state. Then, rest intervals of 5 min were set in re-rest state after compression. The FA value, apparent diffusion coefficient (ADC), and eigenvalues (λ1, λ2, λ3) of the gastrocnemius and soleus muscle were measured at each state. Results The mean FA values increased in all muscles in a compressed state, while the mean λ3 decreased. In all muscles, significant differences were found between the rest and compressed states in terms of mean FA and λ3 ( P < 0.0001). Conclusion We confirmed the reversibility of the DTI metrics, which suggests that there was no muscle injury during this study. In cases of compression without fiber injury, the FA value increases, because fibers are strongly aligned in the longitudinal direction.

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