Search results for "Brain Infarction"
showing 10 items of 17 documents
Anatomical correlates of ocular motor deficits in cerebellar lesions
2009
Humans are able to stabilize the images of moving targets on the retina by means of smooth pursuit eye movements. After the pontine level, all smooth pursuit pathways pass through the cerebellum. Previous animal studies gave evidence that two specific lesion sites within the cerebellum cause smooth pursuit disorders: those of the flocculus/paraflocculus and the vermis including lobule VI, VII, the uvula and the deep cerebellar nuclei. To date, there have been only a few lesion studies in patients with smooth pursuit disorders that do not allow direct comparison with a control group. In the present study, new lesion mapping techniques determined which cerebellar structures were involved in p…
Flat Panel Computed Tomography Pooled Blood Volume and Infarct Prediction in Endovascular Stroke Treatment
2019
Background and Purpose— Patients with large-vessel stroke frequently need to be transferred to comprehensive stroke centers for endovascular treatment. An update of physiological perfusion parameters and stroke progression on arrival is desirable. We examined the reliability of preinterventional pooled blood volume (PBV)-maps acquired by flat-panel detector computed tomography (CT) in the interventional angiography suite. Methods— The volumes of preinterventional perfusion deficit in flat-panel detector CT-PBV source images were compared with final infarct volume on follow-up multislice-CT after endovascular treatment of 29 consecutive patients with occlusion of the middle cerebral artery …
Dysarthria in acute ischemic stroke: lesion topography, clinicoradiologic correlation, and etiology.
2001
Background and purpose: Although dysarthria is a frequent symptom in cerebral ischemia, there is little information on its anatomic specificity, spectrum of associated clinical characteristics, and etiologic mechanisms. Methods: An investigation of 68 consecutive patients with sudden onset of dysarthria due to a single infarction confirmed by MRI or CT was conducted. Results: Dysarthria was associated with a classic lacunar stroke syndrome in 52.9% of patients. Isolated dysarthria and dysarthria–central facial and lingual paresis occurred in 2.9% (n = 2) and 10.3% (n = 7), respectively. Dysarthria–clumsy hand syndrome was observed in 11.7% (n = 8) of patients and associated with pure motor …
MitoKATP-channel opener protects against neuronal death in rat venous ischemia.
2005
OBJECTIVE: Mitochondrial adenosine triphosphate-dependent potassium (mitoK ATP ) channels are present in the brain, and several reports have shown their neuroprotective, preconditioning effect against an ischemic insult. The role of mitoK ATP channels in the penumbra area has not been studied thoroughly. In a model of venous ischemia, widespread penumbra-like low flow areas are created, which are susceptible to cortical spreading depression. Thus, we studied effects of mitoK ATP channels on infarct size in this model. METHODS: Male Wistar rats were subjected to two-vein occlusion by photochemical thrombosis of two adjacent cortical veins combined with KCI-induced cortical spreading depressi…
Caspase-dependent cell death involved in brain damage after acute subdural hematoma in rats
2006
Abstract Traumatic brain injury is associated with acute subdural hematoma (ASDH) that worsens outcome. Although early removal of blood can reduce mortality, patients still die or remain disabled after surgery and additional treatments are needed. The blood mass and extravasated blood induce pathomechanisms such as high intracranial pressure (ICP), ischemia, apoptosis and inflammation which lead to acute as well as delayed cell death. Only little is known about the basis of delayed cell death in this type of injury. Thus, the purpose of the study was to investigate to which extent caspase-dependent intracellular processes are involved in the lesion development after ASDH in rats. A volume o…
Thalamic infarctions cause side-specific suppression of vestibular cortex activations.
2005
H2O15-PET was performed during caloric vestibular stimulation of the right and left external ears in eight right-handed patients with acute unilateral infarctions or haemorrhages of the posterolateral thalamus (four right, four left). The posterolateral thalamus is the relay station for ipsi- and contralateral ascending vestibular input to the multiple multisensory vestibular cortex areas. The aim of this study was to evaluate the differential effects of unilateral vestibular thalamic lesions on thalamo-cortical projections, right hemispheric dominance and reciprocal inhibitory visual-vestibular interaction, as well as perceptual and ocular motor consequences during caloric irrigation. The …
Microglial involvement in neuroplastic changes following focal brain ischemia in rats.
2009
The pathogenesis of ischemic stroke is a complex sequence of events including inflammatory reaction, for which the microglia appears to be a major cellular contributor. However, whether post-ischemic activation of microglial cells has beneficial or detrimental effects remains to be elucidated, in particular on long term brain plasticity events. The objective of our study was to determine, through modulation of post-stroke inflammatory response, to what extent microglial cells are involved in some specific events of neuronal plasticity, neurite outgrowth and synaptogenesis. Since microglia is a source of neurotrophic factors, the identification of the brain-derived neurophic factor (BDNF) as…
In vivo and ex vivo magnetic resonance spectroscopy of the infarct and the subventricular zone in experimental stroke
2015
Ex vivo high-resolution magic-angle spinning (HRMAS) provides metabolic information with higher sensitivity and spectral resolution than in vivo magnetic resonance spectroscopy (MRS). Therefore, we used both techniques to better characterize the metabolic pattern of the infarct and the neural progenitor cells (NPCs) in the ipsilateral subventricular zone (SVZi). Ischemic stroke rats were divided into three groups: G0 (non-stroke controls, n = 6), G1 (day 1 after stroke, n = 6), and G7 (days 6 to 8 after stroke, n =12). All the rats underwent MRS. Three rats per group were analyzed by HRMAS. The remaining rats were used for immunohistochemical studies. In the infarct, both techniques detect…
Incidence and anatomy of gaze-evoked nystagmus in patients with cerebellar lesions.
2011
Background: Disorders of gaze-holding—organized by a neural network located in the brainstem or the cerebellum—may lead to nystagmus. Based on previous animal studies it was concluded that one key player of the cerebellar part of this gaze-holding neural network is the flocculus. Up to now, in humans there are no systematic studies in patients with cerebellar lesions examining one of the most common forms of nystagmus: gaze-evoked nystagmus (GEN). The aim of our present study was to clarify which cerebellar structures are involved in the generation of GEN. Methods: Twenty-one patients with acute unilateral cerebellar stroke were analyzed by means of modern MRI-based voxel-wise lesion-behavi…
Sudden sensorineural hearing loss as prodromal symptom of anterior inferior cerebellar artery infarction.
2011
Sudden sensorineural hearing loss is a clinical condition characterized by a sudden onset of unilateral or bilateral hearing loss. In recent years sudden deafness has been frequently described in association with anterior inferior cerebellar artery (AICA) infarction generally presenting along with other brainstem and cerebellar signs such as ataxia, dysmetria and peripheral facial palsy. The authors report a rare clinical case of a 53-year-old man who suddenly developed hearing loss and tinnitus without any brainstem or cerebellar signs. Computed tomography of his brain was normal, and the audiological results localized the lesion causing deafness to the inner ear. Surprisingly, magnetic re…