scholarly journals Visualization of the protective ability of a free radical trapping compound against rat C6 and F98 gliomas with diffusion tensor fiber tractography

2008 ◽  
Vol 28 (3) ◽  
pp. 574-587 ◽  
Author(s):  
Taketoshi Asanuma ◽  
Sabrina Doblas ◽  
Yasvir A. Tesiram ◽  
Debra Saunders ◽  
Rebecca Cranford ◽  
...  
Keyword(s):  
Free Radical ◽  
Diffusion Tensor ◽  
Fiber Tractography ◽  
Protective Ability ◽  
Radical Trapping

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.

scholarly journals Diffusion tensor imaging and fiber tractography of the median nerve at 1.5T: optimization of b value

2008 ◽  
Vol 38 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Gustav Andreisek ◽  
Lawrence M. White ◽  
Andrea Kassner ◽  
George Tomlinson ◽  
Marshall S. Sussman
Keyword(s):  
Diffusion Tensor Imaging ◽  
Median Nerve ◽  
Diffusion Tensor ◽  
B Value ◽  
Fiber Tractography

Enhanced Fiber Tractography Using Edema Correction: Application and Evaluation in High-Grade Gliomas

Neurosurgery ◽  
2021 ◽  
Author(s):  
Fraser Henderson Jr ◽  
Drew Parker ◽  
Anupa A Vijayakumari ◽  
Mark Elliott ◽  
Timothy Lucas ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Diffusion Tensor ◽  
Free Water ◽  
High Grade Glioma ◽  
Fiber Tracking ◽  
High Grade ◽  
Peritumoral Edema ◽  
Fiber Tractography ◽  
Motor Pathways

Abstract BACKGROUND A limitation of diffusion tensor imaging (DTI)-based tractography is peritumoral edema that confounds traditional diffusion-based magnetic resonance metrics. OBJECTIVE To augment fiber-tracking through peritumoral regions by performing novel edema correction on clinically feasible DTI acquisitions and assess the accuracy of the fiber-tracks using intraoperative stimulation mapping (ISM), task-based functional magnetic resonance imaging (fMRI) activation maps, and postoperative follow-up as reference standards. METHODS Edema correction, using our bi-compartment free water modeling algorithm (FERNET), was performed on clinically acquired DTI data from a cohort of 10 patients presenting with suspected high-grade glioma and peritumoral edema in proximity to and/or infiltrating language or motor pathways. Deterministic fiber-tracking was then performed on the corrected and uncorrected DTI to identify tracts pertaining to the eloquent region involved (language or motor). Tracking results were compared visually and quantitatively using mean fiber count, voxel count, and mean fiber length. The tracts through the edematous region were verified based on overlay with the corresponding motor or language task-based fMRI activation maps and intraoperative ISM points, as well as at time points after surgery when peritumoral edema had subsided. RESULTS Volume and number of fibers increased with application of edema correction; concordantly, mean fractional anisotropy decreased. Overlay with functional activation maps and ISM-verified eloquence of the increased fibers. Comparison with postsurgical follow-up scans with lower edema further confirmed the accuracy of the tracts. CONCLUSION This method of edema correction can be applied to standard clinical DTI to improve visualization of motor and language tracts in patients with glioma-associated peritumoral edema.

scholarly journals T169. SEMANTIC PROCESSING IN RELATION TO ANATOMICAL INTEGRITY OF THE VENTRAL LANGUAGE STREAM IN SCHIZOPHRENIA SPECTRUM DISORDERS

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S295-S296
Author(s):  
Werner Surbeck ◽  
Jürgen Hänggi ◽  
Petra Viher ◽  
André Schmidt ◽  
Erich Seifritz ◽  
...  
Keyword(s):  
Semantic Processing ◽  
Structural Integrity ◽  
Diffusion Tensor ◽  
Three Dimensional ◽  
Fiber Tractography ◽  
Schizophrenia Spectrum Disorders ◽  
Significant Group ◽  
Axial Diffusivity ◽  
Schizophrenia Spectrum ◽  
Spectrum Disorders

Abstract Background Semantic processing anomalies, clinically reflected by disorganized speech are a core symptom of schizophrenia. In the light of accumulating evidence on its prominent role in semantic processing, aberrant structural integrity of the ventral language stream may reflect impaired semantic processing in schizophrenia spectrum disorders (SSD). Methods Comparison of white matter tract integrity in SSD patients and healthy controls using diffusion tensor imaging combined with probabilistic fiber tractography. For the ventral language stream, we assessed the inferior fronto-occipital fasciculus [IFOF], inferior longitudinal fasciculus, and uncinate fasciculus. The arcuate fasciculus and corticospinal tract were used as control tracts. In SSD patients, the relationship between semantic processing impairments and tract integrity was analyzed separately. Three-dimensional tract reconstructions were performed in 45/44 SSD patients/controls (“Bern sample”) and replicated in an independent sample of 24/24 SSD patients/controls (“Basel sample”). Results Multivariate analyses of fractional anisotropy, mean, axial, and radial diffusivity of the left IFOF showed significant differences between SSD patients and controls (p<0.001, ηp2=0.23) in the Bern sample. In SSD, axial diffusivity of the left IFOF was inversely correlated with semantic processing impairments (r=-0.579, p<0.0001). In the Basel sample, significant group differences for the left IFOF were replicated (p<0.01, ηp2=0.29), while the correlation between axial diffusivity of the left IFOF and semantic processing decline (r=-0.376, p=0.09) showed a statistical trend. No significant effects were found for the dorsal language stream. Discussion This work provides direct evidence for the importance of the integrity of the ventral language stream, in particular the left IFOF, in semantic processing deficits in SSD.

scholarly journals Diffusion Tensor Imaging and Fiber Tractography in Children with Craniosynostosis Syndromes

2015 ◽  
Vol 36 (8) ◽  
pp. 1558-1564 ◽  
Author(s):  
B.F.M. Rijken ◽  
A. Leemans ◽  
Y. Lucas ◽  
K. van Montfort ◽  
I.M.J. Mathijssen ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Diffusion Tensor ◽  
Fiber Tractography

Human Brain Diffusion Tensor Imaging Visualization With Virtual Reality

2010 ◽  
Author(s):  
Bin Chen ◽  
John Moreland
Keyword(s):  
Virtual Reality ◽  
Diffusion Tensor Imaging ◽  
White Matter ◽  
Diffusion Tensor ◽  
Biological Tissues ◽  
Head Tracking ◽  
Fiber Tractography ◽  
Brain White Matter ◽  
Diffusion Tensors ◽  
Visualization Techniques

Magnetic resonance diffusion tensor imaging (DTI) is sensitive to the anisotropic diffusion of water exerted by its macromolecular environment and has been shown useful in characterizing structures of ordered tissues such as the brain white matter, myocardium, and cartilage. The water diffusivity inside of biological tissues is characterized by the diffusion tensor, a rank-2 symmetrical 3×3 matrix, which consists of six independent variables. The diffusion tensor contains much information of diffusion anisotropy. However, it is difficult to perceive the characteristics of diffusion tensors by looking at the tensor elements even with the aid of traditional three dimensional visualization techniques. There is a need to fully explore the important characteristics of diffusion tensors in a straightforward and quantitative way. In this study, a virtual reality (VR) based MR DTI visualization with high resolution anatomical image segmentation and registration, ROI definition and neuronal white matter fiber tractography visualization and fMRI activation map integration is proposed. The VR application will utilize brain image visualization techniques including surface, volume, streamline and streamtube rendering, and use head tracking and wand for navigation and interaction, the application will allow the user to switch between different modalities and visualization techniques, as well making point and choose queries. The main purpose of the application is for basic research and clinical applications with quantitative and accurate measurements to depict the diffusivity or the degree of anisotropy derived from the diffusion tensor.

MR neurography of the median nerve at 3.0T: Optimization of diffusion tensor imaging and fiber tractography

2012 ◽  
Vol 81 (7) ◽  
pp. e775-e782 ◽  
Author(s):  
Roman Guggenberger ◽  
Patrick Eppenberger ◽  
Daniel Markovic ◽  
Daniel Nanz ◽  
Avneesh Chhabra ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
Median Nerve ◽  
Diffusion Tensor ◽  
Fiber Tractography ◽  
Mr Neurography

scholarly journals Pengaruh Penambahan Rempah dan Bentuk Minuman terhadap Aktivitas Antioksidan Berbagai Minuman Tradisional Indonesia

2017 ◽  
Vol 37 (1) ◽  
pp. 7 ◽  
Author(s):  
Aisyah Tri Septiana ◽  
Mohammad Samsi ◽  
Mustaufik Mustaufik
Keyword(s):  
Antioxidant Activity ◽  
Linoleic Acid ◽  
Free Radical ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Total Phenolic ◽  
Phenolic Contents ◽  
Beverage Type ◽  
Radical Trapping ◽  
Palm Sugar

Indonesia traditional beverages such as minuman jahe, kunyit asam, beras kencur, and minuman temulawak are usually made with the addition of spices. They can be served in the form of  liquid or powder. This research was aimed to study the effect of  the beverage type, addition of spices, and the form of product on their antioxidant activity. The type of sugar used in this study was palm sugar juice. Total phenolic contents were measured to  indicate the level of antioxidants. Measurement of antioxidant  activity was conducted by analyzing malonaldehyde from linoleic  acid and capturing capacity of DPPH radical. The results showed  that Indonesian traditional beverage could inhibit the oxidation of linoleic acid and capture free radicals. Free radical capturing  capacity of curcuma beverage greater than other beverages, but  the malonaldehyde (MDA) inhibitor effect was not different. Total phenolic content of curcuma tended to be higher than the other traditional beverages. The addition of spices could raise the level  of total phenolic content in beverages and increase free radical  trapping capacity. Drying the beverages into powder could reduce the levels of total phenolic content and but did not reduce the  antioxidant activity. ABSTRAKMinuman tradisional Indonesia seperti minuman jahe, kunyit  asam, beras kencur, dan minuman temulawak biasanya dibuat  dengan tambahan berbagai rempah. Minuman tersebut dapat  disajikan dalam bentuk cair maupun serbuk. Penelitian ini  bertujuan untuk mengetahui pengaruh jenis minuman,  penambahan rempah tambahan, dan bentuk minuman terhadap aktivitas antioksidan minuman. Jenis gula yang ditambahkan  adalah gula nira. Jenis antioksidan yang diuji adalah total fenolik. Pengukuran aktivitas antioksidan dilakukan dengan uji  penghambatan malonaldehid dan kapasitas penangkapan radikal  DPPH. Hasil penelitian menunjukkan bahwa minuman  tradisional Indonesia dapat menghambat oksidasi asam linoleat dan menangkap radikal bebas. Kapasitas penangkapan radikal  bebas oleh minuman temulawak lebih besar dibandingkan  minuman yang lain tetapi kemampuan penghambatan  malonaldehid (MDA) oleh minumaan tradisional tidak berbeda.  Total fenolik minuman temulawak cenderung lebih besar  dibandingkan minuman tradisional yang lain. Penambahan  rempah-rempah dapat meningkatkan kadar total fenolik  minuman dan meningkatkan kapasitas penangkapan radikal  bebas. Pembuatan minuman serbuk pada penelitian ini dapat  menurunkan kadar total fenolik tetapi tidak menurunkan aktivitas antioksidan.

scholarly journals NXY-059, the free radical trapping nitrone-based agent, reduces hemiparesis and reduces grey and white matter damage after focal cerebral ischemia in monkeys

Stroke ◽  
2001 ◽  
Vol 32 (suppl_1) ◽  
pp. 327-327
Author(s):  
J Wb Marshall ◽  
K J Duffin ◽  
A R Green ◽  
R M Ridley
Keyword(s):  
Free Radical ◽  
White Matter ◽  
Acute Stroke ◽  
Functional Disability ◽  
Focal Cerebral Ischemia ◽  
Spatial Neglect ◽  
Histopathological Analysis ◽  
White Matter Damage ◽  
Radical Trapping ◽  
Published Evidence

60 There is little published evidence for protection of white matter with neuroprotective drugs in animal models of stroke, yet white matter protection may be important in achieving clinical efficacy. We have examined the effects of NXY-059, a nitrone-based free radical trapping agent, on long-term functional disability in a primate model of stroke. We also examined histopathological effects, including analyses of grey and white matter damage. Five minutes after unilateral permanent middle cerebral artery occlusion, marmosets received a 1 ml i.v. infusion of saline (n=5) or NXY-059 (28 mg/kg) (n=6) and osmotic minipumps (model 2001D) were implanted s.c. to provide continuous drug or saline infusion for 48 h. Drug-filled pumps released NXY-059 at a rate of approximately 16 mg/kg/h. The plasma unbound drug concentration at 24 h was 76.3 ± 5.7 μM, a level well tolerated in acute stroke patients. The monkeys had been trained and tested on a variety of behavioral tasks before surgery. NXY-059-treated monkeys were significantly better at reaching with their contralesional arm than were saline-treated monkeys when re-tested 3 (p<0.01) and 10 weeks (p<0.01) after surgery. NXY-059-treatment also significantly reduced spatial neglect measured 3 weeks after surgery (p<0.01) compared with the saline group. After behavioral testing was complete, histopathological analysis showed NXY-059-treated monkeys had significantly smaller infarcts than saline-treated monkeys (F (1, 10)=5.21, p<0.05). NXY-059 reduced overall infarct size by 51%, damage to the cortex was reduced by 54%, white matter by 52%, caudate by 49%, and putamen by 33% compared with saline-treated monkeys. In conclusion, NXY-059 substantially lessened the functional disability in these monkeys. This drug protects not only cortical tissue, but also white matter and subcortical structures against ischemic damage. Together these findings bode well for advancing this drug to further clinical trials for its use in acute stroke.

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