Read by QxMD icon Read


Vera Dinkelacker, Sophie Dupont, Séverine Samson
The new classification of epilepsy stratifies the disease into an acute level, based on seizures, and an overarching chronic level of epileptic syndromes (Berg et al., 2010). In this new approach, seizures are considered either to originate and evolve in unilateral networks or to rapidly encompass both hemispheres. This concept extends the former vision of focal and generalized epilepsies to a genuine pathology of underlying networks. These key aspects of the new classification can be linked to the concept of cognitive curtailing in focal epilepsy...
October 17, 2016: Epilepsy & Behavior: E&B
Qiang Yu, David Reutens, Kieran O'Brien, Viktor Vegh
OBJECTIVES: Tissue microstructure features, namely axon radius and volume fraction, provide important information on the function of white matter pathways. These parameters vary on the scale much smaller than imaging voxels (microscale) yet influence the magnetic resonance imaging diffusion signal at the image voxel scale (macroscale) in an anomalous manner. Researchers have already mapped anomalous diffusion parameters from magnetic resonance imaging data, but macroscopic variations have not been related to microscale influences...
October 18, 2016: Human Brain Mapping
Weifei Wu, Jie Liang, Ying Chen, Aihua Chen, Bin Wu, Zong Yang
To investigate the microstructural changes in compressed nerves using diffusion tensor imaging (DTI) of herniated disc treated with percutaneous transforaminal endoscopic discectomy.Diffusion tensor imaging has been widely used to visualize peripheral nerves, and the microstructure of compressed nerve roots can be assessed using DTI. However, the microstructural changes after surgery are not well-understood in patients with lumbar disc herniation.Thirty-four consecutive patients with foraminal disc herniation affecting unilateral sacral 1 (S1) nerve roots were enrolled in this study...
October 2016: Medicine (Baltimore)
Allen Q Ye, Olusola A Ajilore, Giorgio Conte, Johnson GadElkarim, Galen Thomas-Ramos, Liang Zhan, Shaolin Yang, Anand Kumar, Richard L Magin, Angus G Forbes, Alex D Leow
This paper describes novel methods for constructing the intrinsic geometry of the human brain connectome using dimensionality-reduction techniques. We posit that the high-dimensional, complex geometry that represents this intrinsic topology can be mathematically embedded into lower dimensions using coupling patterns encoded in the corresponding brain connectivity graphs. We tested both linear and nonlinear dimensionality-reduction techniques using the diffusion-weighted structural connectome data acquired from a sample of healthy subjects...
December 2015: Brain Informatics
RaviK Shastri, GaurangV Shah, Page Wang, Patricia Cagnoli, Tobias Schmidt-Wilcke, Joseph McCune, Richard Harris, PiaC Sundgren
PURPOSE: Systemic lupus erythematosus (SLE) is a predominantly female autoimmune disease that can affect the central nervous system. Neuropsychiatric symptoms are found in 25-70% of SLE patients. Using diffusion tensor imaging, various studies have reported changes in white matter integrity in SLE patients with neuropsychiatric symptoms (NPSLE patients). The purpose of this study was to investigate if changes can be detected in the individual white matter tracts in SLE patients regardless if neuropsychiatric symptoms are present or not...
October 13, 2016: Academic Radiology
Tamara Ius, Luca Turella, Giada Pauletto, Miriam Isola, Marta Maieron, Giovanni Sciacca, Riccardo Budai, Serena D'Agostini, Roberto Eleopra, Miran Skrap
BACKGROUND: Pre-operative diffusion tensor tractography (DTT) has recently been utilized to aid in the mapping of functional pathways in order to limit damage associated with resection of low-grade gliomas. OBJECTIVE: To assess the predictive capacity of DTT as a biomarker of post-operative motor outcomes in patients with low-grade gliomas (LGGs) involving the corticospinal tract (CST). CST parameters obtained using a quantitative fiber-tracking approach were used to investigate the reliability of the DTT biomarker by comparing their values in the tumoral (Tcst) and healthy (Hcst) hemispheres...
October 12, 2016: World Neurosurgery
Alexandra L Clark, Lisa Delano-Wood, Scott F Sorg, Madeleine L Werhane, Karen L Hanson, Dawn M Schiehser
No known studies have directly examined white matter microstructural correlates of cognitive fatigue post-TBI in a Veteran sample. We therefore investigated the relationship between cognitive fatigue and white matter integrity in Veterans with history of mild to moderate TBI (mmTBI). 59 Veterans (TBI = 34, Veteran Controls [VCs] = 25]) with and without history of mmTBI underwent structural 3T DTI scans and completed questionnaires related to cognitive fatigue and psychiatric symptoms. Tractography was employed on six regions of interest, including the anterior and posterior limbs of the internal capsule; genu; body and splenium of the corpus callosum; and cingulum bundle...
October 6, 2016: Brain Imaging and Behavior
Michele R Colonna, Giuseppe Tallarida, Francesco Stagno d'Alcontres, Salvatore Noto, Aurora Parodi, Alberto Tagliafico
Five years after both right ulnar and median nerve decompression for paraesthesias and palsy, a patient, coming from Nigeria but living in Italy, came to our unit claiming to have persistent pain and combined median and ulnar palsy. Under suspicion of leprosy, skin and left sural nerve biopsy were performed. Skin tests were negative, but Schwann cells resulted as positive for acid-fast bacilli (AFB), leading to the diagnosis of Pure Neuritic Leprosy (PNL). The patient was given PB multidrug therapy and recovered from pain in two months...
2016: Case Reports in Neurological Medicine
Jidan Zhong, David Q Chen, Matthew Walker, Adam Waspe, Thomas Looi, Karolina Piorkowska, James M Drake, Mojgan Hodaie
An increasing number of applications use the postnatal piglet model in neuroimaging studies, however, these are based primarily on T1 weighted image templates. There is a growing need for a multimodal structural brain template for a comprehensive depiction of the piglet brain, particularly given the growing applications of diffusion weighted imaging for characterizing tissue microstructures and white matter organization. In this study, we present the first multimodal piglet structural brain template which includes a T1 weighted image with tissue segmentation probability maps, diffusion weighted metric templates with multiple diffusivity maps, and population-based whole-brain fiber tracts for postnatal piglets...
2016: Frontiers in Neuroanatomy
Catarina Guise, Margarida M Fernandes, Sudhir Pathak, Walter Schneider, Raul Fangueiro
Current brain imaging methods largely fail to provide detailed information about the location and severity of axonal injuries, and do not anticipate recovery of the patients with traumatic brain injury. High-Definition Fiber Tractography appears as a novel imaging modality based on water motion in the brain that allows for direct visualization and quantification of the degree of axons damage, thus predicting the functional deficits due to traumatic axonal injury and loss of cortical projections. This neuroimaging modality still faces major challenges because it lacks a "gold standard" for the technique validation and respective quality control...
October 10, 2016: ACS Applied Materials & Interfaces
Nicole Labra, Pamela Guevara, Delphine Duclap, Josselin Houenou, Cyril Poupon, Jean-François Mangin, Miguel Figueroa
This paper presents an algorithm for fast segmentation of white matter bundles from massive dMRI tractography datasets using a multisubject atlas. We use a distance metric to compare streamlines in a subject dataset to labeled centroids in the atlas, and label them using a per-bundle configurable threshold. In order to reduce segmentation time, the algorithm first preprocesses the data using a simplified distance metric to rapidly discard candidate streamlines in multiple stages, while guaranteeing that no false negatives are produced...
October 8, 2016: Neuroinformatics
Weihong Yuan, Artur Meller, Joshua S Shimony, Tiffany Nash, Blaise V Jones, Scott K Holland, Mekibib Altaye, Holly Barnard, Jannel Phillips, Stephanie Powell, Robert C McKinstry, David D Limbrick, Akila Rajagopal, Francesco T Mangano
Neuroimaging research in surgically treated pediatric hydrocephalus patients remains challenging due to the artifact caused by programmable shunt. Our previous study has demonstrated significant alterations in the whole brain white matter structural connectivity based on diffusion tensor imaging (DTI) and graph theoretical analysis in children with hydrocephalus prior to surgery or in surgically treated children without programmable shunts. This study seeks to investigate the impact of brain injury on the topological features in the left hemisphere, contratelateral to the shunt placement, which will avoid the influence of shunt artifacts and makes further group comparisons feasible for children with programmable shunt valves...
2016: NeuroImage: Clinical
Laurie M Baker, Ryan P Cabeen, Sarah Cooley, David H Laidlaw, Robert H Paul
This paper reviews basic methods and recent applications of length-based fiber bundle analysis of cerebral white matter using diffusion magnetic resonance imaging (dMRI). Diffusion weighted imaging (DWI) is a dMRI technique that uses the random motion of water to probe tissue microstructure in the brain. Diffusion tensor imaging (DTI) is an extension of DWI that measures the magnitude and direction of water diffusion in cerebral white matter, using either voxel-based scalar metrics or tractography-based analyses...
April 2016: Technology and Innovation
Yupeng Wu, Dandan Sun, Yong Wang, Yibao Wang
The definitive structure and functional role of the inferior fronto-occipital fasciculus (IFOF) are still controversial. In this study, we aimed to investigate the connectivity, asymmetry, and segmentation patterns of this bundle. High angular diffusion spectrum imaging (DSI) analysis was performed on 10 healthy adults and a 90-subject DSI template (NTU-90 Atlas). In addition, a new tractography approach based on the anatomic subregions and two regions of interest (ROI) was evaluated for the fiber reconstructions...
2016: Frontiers in Neuroanatomy
N De Geeter, P Lioumis, A Laakso, G Crevecoeur, L Dupré
When delivered over a specific cortical site, TMS can temporarily disrupt the ongoing process in that area. This allows mapping of speech-related areas for preoperative evaluation purposes. We numerically explore the observed variability of TMS responses during a speech mapping experiment performed with a neuronavigation system. We selected four cases with very small perturbations in coil position and orientation. In one case (E) a naming error occurred, while in the other cases (NEA, B, C) the subject appointed the images as smoothly as without TMS...
October 7, 2016: Physics in Medicine and Biology
Cenan Hepdurgun, Özgün Özalay, Seda Eroğlu, Irmak Polat Nazlı, Ömer Kitiş, Ali Saffet Gönül
The majority of the research studying the prefrontal region has focused on gray matter injury. However, recent studies show that damage to white matter also contributes to the development of cognitive impairment after traumatic brain injury (TBI). Through the use of diffusion tensor imaging (DTI), it is now possible to assess the white matter fiber pathways between brain regions. With Diffusion Tensor Tractography (DTT), fibers of interest can be three dimensionally reconstructed and associated measurements can be performed...
2016: Türk Psikiyatri Dergisi, Turkish Journal of Psychiatry
Jiafeng Chen, Lijun Zhu, He Li, Ziwen Lu, Xin Chen, Shaokuan Fang
Multiple sclerosis (MS) is easily detected by routine magnetic resonance imaging (MRI). However, it is not possible to detect early or occult lesions in MS by routine MRI, and this may explain the inconsistency between the severity of the lesions found by MRI and the degree of clinical disability of patients with MS. The present study included 10 patients with relapsing-remitting MS and 10 healthy volunteers. Each patient underwent routine 3.0 T MRI, diffusion tensor imaging (DTI), and diffusion tensor tractography (DTT)...
October 2016: Experimental and Therapeutic Medicine
Matthew P Hoffman, Erik N Taylor, George E Aninwene, Sakthivel Sadayappan, Richard J Gilbert
Contraction of muscular tissue requires the synchronized shortening of myofibers arrayed in complex geometrical patterns. Imaging such myofiber patterns with diffusion-weighted MRI reveals architectural ensembles that underlie force generation at the organ scale. Restricted proton diffusion is a stochastic process resulting from random translational motion that may be used to probe the directionality of myofibers in whole tissue. During diffusion-weighted MRI, magnetic field gradients are applied to determine the directional dependence of proton diffusion through the analysis of a diffusional probability distribution function (PDF)...
October 2, 2016: Microscopy Research and Technique
Sandra G J Boccard, Pedro Rebelo, Binith Cheeran, Alexander Green, James J FitzGerald, Tipu Z Aziz
BACKGROUND: Deep Brain Stimulation (DBS) is a well-established treatment to reduce tremor, notably in Parkinson Disease. DBS may also be effective in posttraumatic tremor, one of the most common movement disorders caused by head injury. However, these cohorts of patients often have multiple lesions that may impact the outcome depending on which fibre tracts are affected. CASE DESCRIPTION: A 20-year-old man presented after road traffic accident with severe closed head injury and polytrauma...
September 29, 2016: World Neurosurgery
Ji Chen, Jinqiang Li, Qiaoqing Han, Jianzhong Lin, Tianhe Yang, Ziqian Chen, Jiaxing Zhang
BACKGROUND: Structural and functional networks can be reorganized to adjust to environmental pressures and physiologic changes in the adult brain, but such processes remain unclear in prolonged adaptation to high-altitude (HA) hypoxia. This study aimed to characterize the interhemispheric functionally and structurally coupled modifications in the brains of adult HA immigrants. METHODS: We performed resting-state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in 16 adults who had immigrated to the Qinghai-Tibet Plateau (2300-4400 m) for 2 years and in 16 age-matched sea-level (SL) controls...
September 2016: Brain and Behavior
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"