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Cerebral Peduncle (cerebral + peduncle)
Selected AbstractsrFVIIa, for acute rebleeding of a cerebral cavernous malformationEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2007K. Engelhardt Recurrent bleeding episodes of cavernomas especially in the brainstem can cause progressive neurological deficits. Therefore brainstem cavernomas are still a therapeutic dilemma and a treatment challenge for the neuro critical care community. We report a 39-year-old woman with spontaneous ataxia diplopia and vomiting, who has been treated for multiple intracerebral cavernomas during the last 10 years. A cerebral computed tomography (cCT) revealed a re-bleeding cavernoma in the left cerebral peduncle with consecutive obstructive hydrocephalus. As a result of the difficult anatomical location, no surgical approach was possible. As an off-label treatment, recombinant activated factor VII (rFVIIa) was administered to prevent possible further bleeding and especially further sequelae. The patient recovered well and no adverse events and especially no further bleeding of the cavernoma were observed. To our knowledge, this is the first report of the safe and successful use of rFVIIa to treat re-bleeding episodes in cavernomas. Further clinical studies are needed to specify the future potential of rFVIIa. [source] A multiparametric evaluation of regional brain damage in patients with primary progressive multiple sclerosisHUMAN BRAIN MAPPING, Issue 9 2009Antonia Ceccarelli Abstract The purpose of this study is to define the topographical distribution of gray matter (GM) and white matter (WM) damage in patients with primary progressive multiple sclerosis (PPMS), using a multiparametric MR-based approach. Using a 3 Tesla scanner, dual-echo, 3D fast-field echo (FFE), and diffusion tensor (DT) MRI scans were acquired from 18 PPMS patients and 17 matched healthy volunteers. An optimized voxel-based (VB) analysis was used to investigate the patterns of regional GM density changes and to quantify GM and WM diffusivity alterations of the entire brain. In PPMS patients, GM atrophy was found in the thalami and the right insula, while mean diffusivity (MD) changes involved several cortical-subcortical structures in all cerebral lobes and the cerebellum. An overlap between decreased WM fractional anisotropy (FA) and increased WM MD was found in the corpus callosum, the cingulate gyrus, the left short temporal fibers, the right short frontal fibers, the optic radiations, and the middle cerebellar peduncles. Selective MD increase, not associated with FA decrease, was found in the internal capsules, the corticospinal tracts, the superior longitudinal fasciculi, the fronto-occipital fasciculi, and the right cerebral peduncle. A discrepancy was found between regional WM diffusivity changes and focal lesions because several areas had DT MRI abnormalities but did not harbor T2-visible lesions. Our study allowed to detect tissue damage in brain areas associated with motor and cognitive functions, which are known to be impaired in PPMS patients. Combining regional measures derived from different MR modalities may be a valuable tool to improve our understanding of PPMS pathophysiology. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] Diffusion Tensor Tractography-based Analysis of the Pyramidal Tract in Patients with Amyotrophic Lateral SclerosisJOURNAL OF NEUROIMAGING, Issue 3 2008Yoon-Ho Hong MD ABSTRACT BACKGROUND AND PURPOSE We attempted to measure DTI parameters of the brainstem pyramidal tract using two approaches, ie, simple ROI and tract-specific analyses. Results obtained for healthy subjects and ALS patients were compared. METHODS DTI was performed using a single shot SE-EPI with 25 noncollinear diffusion gradient directions (b= 1000 second/mm2) and with no diffusion gradient on a 3.0-T MR system in 10 ALS patients and in 8 age- and sex-matched normal controls. To delineate the brainstem pyramidal tract, tractography was performed using two ROIs, ie, a seed ROI at the cerebral peduncle (ROI-1) and a target ROI at the lower pons (ROI-2). ROI-1 was subsequently restricted to voxels that contained streamlines in the tract reconstruction, thus creating a sub-ROI. RESULTS Mean fractional anisotropy (FA) and mean diffusivity values were highly reproducible by tract specific analysis, whereas simple ROI analysis yielded larger variabilities between operators. FA values were significantly lower in ALS patients than in normal controls in the tractography-derived sub-ROI (P= .01), but not in the seed or target ROIs. CONCLUSIONS These results suggest, compared with simple ROI analysis, that tract-specific analysis using DTI fiber-tracking is more reliable and sensitive for detecting upper motor neuron pathology in ALS. [source] Arm chorea secondary to an unruptured giant aneurysm,MOVEMENT DISORDERS, Issue 11 2003Luis M. Barreiro De Madariaga MD Abstract We describe the case of a 20-year-old male who developed right-arm choreic movements secondary to a giant unruptured aneurysm impinging upon the left thalamus, putamen, globus pallidus, cerebral peduncle, midbrain, and subthalamic nucleus. The aneurysm was treated successfully with coils and a supraclinoid balloon. Abnormal movements initially failed to ameliorate, but within a few months, it was possible to discontinue symptomatic haloperidol therapy, with only mild residual abnormal movements. © 2003 Movement Disorder Society [source] Three-dimensional MRI of cerebral projections in rat brain in vivo after intracortical injection of MnCl2NMR IN BIOMEDICINE, Issue 5 2003Peter R. Allegrini Abstract In this study we investigated the potential of in vivo MRI detection of axonal Mn2+ transport for tracing neuronal projections originating in the sensorimotor cortex in healthy and lesioned rat brains. Special attention was given to the potential of visualizing neuronal sprouting of central nervous system across the midline. After injecting unchelated MnCl2 into the forelimb area of sensorimotor cortex of 18 healthy and 10 lesioned rats corticofugal projections could be traced through the internal capsule to the cerebral peduncle and the pyramidal decussation. Although the neuronal tract was visible as early as 6,h after MnCl2 injection, best contrast was achieved after 24,48,h. Beside the cortico-spinal tract, the cortico-thalamic fibres were also visualized by anterograde Mn2+ transport. Cortico-striatal fibres were partially masked by the very high signal near the MnCl2 injection site but could be discerned as well. Slight, diffuse signal enhancement of cortical tissue contralateral to the MnCl2 injection site in healthy rat brains suggests interhemispheric connections or passive diffusion of Mn2+. However, enhanced fibre tract contrast connecting both hemispheres was visible 16 weeks after onset of focal photothrombotic cortical injury. In conclusion our study has shown that we were able to visualize reproducibly the main descending corticofugal projections and interhemispheric connections by non-invasive MRI after localized injection of MnCl2. The appearence of interhemispheric Mn2+ -enhanced fibres after photothrombotic focal injury indicates that the method may bear potential to follow non-invasively gross plastic changes of connectivity in the brain after injury. Copyright © 2001 John Wiley & Sons, Ltd. [source] Organization of tectopontine terminals within the pontine nuclei of the rat and their spatial relationship to terminals from the visual and somatosensory cortexTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 3 2005Cornelius Schwarz Abstract We investigated the spatial relationship of axonal and dendritic structures in the rat pontine nuclei (PN), which transfer visual signals from the superior colliculus (SC) and visual cortex (A17) to the cerebellum. Double anterograde tracing (DiI and DiAsp) from different sites in the SC showed that the tectal retinotopy of visual signals is largely lost in the PN. Whereas axon terminals from lateral sites in the SC were confined to a single terminal field close to the cerebral peduncle, medial sites in the SC projected to an additional dorsolateral one. On the other hand, axon terminals originating from the two structures occupy close but, nevertheless, totally nonoverlapping terminal fields within the PN. Furthermore, a quantitative analysis of the dendritic trees of intracellularly filled identified pontine projection neurons showed that the dendritic fields were confined to either the SC or the A17 terminal fields and never extended into both. We also investigated the projections carrying cortical somatosensory inputs to the PN as these signals are known to converge with tectal ones in the cerebellum. However, terminals originating in the whisker representation of the primary somatosensory cortex and in the SC were located in segregated pontine compartments as well. Our results, therefore, point to a possible pontocerebellar mapping rule: Functionally related signals, commonly destined for common cerebellar target zones but residing in different afferent locations, may be kept segregated on the level of the PN and converge only later at specific sites in the granular layer of cerebellar cortex. J. Comp. Neurol. 484:283,298, 2005. © 2005 Wiley-Liss, Inc. [source] Quantitative diffusion tensor imaging for evaluation of motor function in patients with brain infarctsACTA NEUROLOGICA SCANDINAVICA, Issue 5 2010X. Liu Liu X, Li L, Tian W, Zhao C, Dogra V. Quantitative diffusion tensor imaging for evaluation of motor function in patients with brain infarcts. Acta Neurol Scand: 2010: 121: 315,319. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective,,, To evaluate the quantitative diffusion value in ipsilateral cerebral peduncle of patients with differing motor function abilities and analyse the thresholds discriminating the poor motor function disability. Method,,, Twenty-nine patients who previously suffered stroke underwent diffusion tensor imaging examinations. Motor function was evaluated 8 months after the event. The ipsilateral apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of cerebral peduncle and ADC ratio and FA ratio of patients with different motor function scales were analysed. Results,,, The ipsilateral FA value and FA ratio were distinctly different in patients with different motor function scales, and significantly correlated with the motor function scales. There was no significant difference of ipsilateral ADC and ADC ratio, and neither had correlation with motor function scale. The patients with poor motor function scale could be discriminated by the cutoff value of ipsilateral FA of 0.453 and FA ratio of 0.623 with sensitivity of 90%, 75% and specificity of 88.9%, 88.9% respectively. Conclusions,,, The ipsilateral FA value and FA ratio were feasible and better imaging indices in discriminating patients with poor motor function ability. [source] Brain structural damage in spinocerebellar ataxia type 2.MOVEMENT DISORDERS, Issue 6 2008A voxel-based morphometry study Abstract Voxel-based morphometry (VBM) enables an unbiased in-vivo whole-brain quantitative analysis of differences in gray matter (GM), white matter (WM) and cerebro-spinal fluid (CSF) volumes. We assessed with VBM 20 spinocerebellar ataxia Type 2 (SCA2) patients with mild or moderate cerebellar deficit and 20 age and sex-matched healthy controls. SCA2 patients showed a significant (P < 0.05 corrected for multiple comparison) symmetric loss of GM in the cerebellar vermis and hemispheres sparing lobules I,II, Crus II,VII, and X, and of the WM in the peridentate region, middle cerebellar peduncles, dorsal pons, and cerebral peduncles. The CSF volume was increased in the posterior cranial fossa. No GM, WM or CSF volume changes were observed in the supratentorial compartment. A mild (P < 0.05, >0.01) correlation was observed between the GM and WM loss and severity of the neurological deficit. In SCA2 patients with mild to moderate cerebellar deficit, GM and WM volume loss and CSF volume increase are confined to the posterior cranial fossa. © 2008 Movement Disorder Society [source] | |||||||||||||