Introduction: There are reports of an ischemic stroke during intravenous recombinant tissue-type plasminogen activator (rtPA) for evolving myocardial infarction (MI), and the risk of stroke shortly after an acute MI seems to be higher than in the control population, attributed to intracardiac thrombus formation.
Case Report: We report a case of fatal MI developing immediately after the start of rtPA infusion for middle cerebral artery stroke in an 88-year-old woman. We assume that the systemic thrombolysis with rtPA led to the fragmentation of an underlying cardiac thrombus, which embolized and occluded the coronary artery and caused MI.
Background And Purpose: We aimed to validate the usefulness of the Essen Stroke Risk Score (ESRS) to predict stroke recurrence in a hospital-based follow-up study.
Methods: We followed up 730 consecutive patients admitted to a neurological stroke unit in Berlin, Germany, with ischemic stroke (IS) or transient ischemic attack (TIA). The mean follow-up time was 13.
Background: There is increasing evidence for hormone-dependent modification of function and behavior during the menstrual cycle, but little is known about associated short-term structural alterations of the brain. Preliminary studies suggest that a hormone-dependent decline in brain volume occurs in postmenopausal, or women receiving antiestrogens, long term. Advances in serial MR-volumetry have allowed for the accurate detection of small volume changes of the brain.
View Article and Find Full Text PDFBackground: The intention of this study was the prospective analysis of Wallerian degeneration of the pyramidal tract after paramedian pons infarction.
Methods: Patients with paramedian pons infarct underwent MR imaging including diffusion tensor imaging at admission and got 1-3 MR scans up to 6 months of follow-up. Clinical scores and transcranial magnetic stimulation were acquired in the acute phase and 3-6 months later.
Introduction: Although several reports about volumetric determination of the pituitary gland exist, volumetries have been solely performed by indirect measurements or manual tracing on the gland's boundaries. The purpose of this study was to evaluate the accuracy and reproducibility of a novel semi-automatic MR-based segmentation technique.
Methods: In an initial technical investigation, T1-weighted 3D native magnetised prepared rapid gradient echo sequences (1.
The clinical differentiation between stroke and seizure is usually straightforward but postictal neurological deficits can be mistaken for stroke in case no detailed medical history is available. Up to now, the imaging findings of Todd's paresis are not well described. This case report demonstrates that postictal paresis can be accompanied by a reversible global hemispheric hypoperfusion as measured with perfusion MRI indicating transient but profound cerebrovascular dysfunction in postictal paresis.
View Article and Find Full Text PDFPurpose: To study the time course of diffusion imaging at the lesion site in brainstem infarcts.
Materials And Methods: Sequential MR scans were acquired from 24 patients with brainstem infarcts. Diffusion-weighted images (DWI), T(2)-weighted images (T(2)w), maps of apparent diffusion coefficient, and maps of fractional anisotropy were generated from each MR scan.
Diffusion tensor imaging (DTI) studies of schizophrenia have revealed white matter abnormalities in several areas of the brain. The functional impact on either psychopathology or cognition remains, however, poorly understood. Here we analysed both functional MRI (during a working memory task) and DTI data sets in 18 patients with schizophrenia and 18 controls.
View Article and Find Full Text PDFIEEE Trans Biomed Eng
November 2006
This paper reviews the application of continuous recurrent neural networks with time-varying weights to pattern recognition tasks in medicine. A general learning algorithm based on Pontryagin's maximum principle is recapitulated, and possibilities of improving the generalization capabilities of these networks are given. The effectiveness of the methods is demonstrated by three different real-world examples taken from the fields of anesthesiology, orthopedics, and radiology.
View Article and Find Full Text PDFSturge-Weber syndrome (SWS) is a congenital disorder characterized by a vascular birthmark and neurological abnormalities. Typical imaging findings using MRI or CT are superficial cerebral calcification, atrophy and leptomeningeal enhancement. We present a neonate diagnosed with SWS because of a port-wine stain.
View Article and Find Full Text PDFSpontaneous intracranial hypotension (SIH) is known to cause postural headache, often combined with auditory, and vestibular symptoms, nausea, vomiting, and diplopia. We report a 63-year-old male patient who for the first time developed a depressive episode followed by acute manic symptoms during the course of SIH, both relieved after treatment of the underlying organic disturbance.
View Article and Find Full Text PDFNeurofibromatosis (NF) is the most common of the phakomatoses, with a prevalence of 1 in 3-4,000. Many organ systems can be affected. In addition to multiple peripheral neurofibromas, NF I predisposed to CNS tumors including optic glioma, astrocytoma and plexiform neurofibroma.
View Article and Find Full Text PDFWe present the unique case of a patient with a circumscribed solitary cerebral metastasis of a malignant melanoma extending from the medial part of the superior temporal gyrus to the lower part of the 1st long insular gyrus causing gait and stance instability and an ipsiversive tilt of the subjective visual vertical. Oculomotor disorders could not be detected. We suggest that the superior temporal gyrus is likely to be involved in spatial orientation presumably using otolithic information.
View Article and Find Full Text PDFSeveral functional brain imaging studies of pain using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have shown that painful stimulation causes activation of different brain areas. The aim of the present study was to develop and implement painful stimulation of the trigeminal nerve, which can be applied with event-related paradigms by using MRI. Twelve healthy, right-handed volunteers were examined.
View Article and Find Full Text PDFThree patients with acute large paramedian ponto-mesencephalic infarctions developed a bilateral retrograde degeneration of the medial cerebellar peduncles within 4 months after the insult. In an initial magnetic resonance imaging (MRI) within the first 2 weeks, the medial cerebellar peduncles showed normal intensities, but a control MRI after 4 months showed bright hyperintensities in the T2-TSE weighted images, and moderately increased signal intensities in echo planar imaging-diffusion weighted imaging were seen, possibly representing bilateral Wallerian degeneration of the cerebellar-pontine fibers.
View Article and Find Full Text PDFPurpose: To investigate whether routine magnetic resonance (MR) imaging of the brain with a whole-body 1.5-T imager affects the results of subsequent magnetoencephalography (MEG).
Materials And Methods: Nine healthy volunteers (six women, mean age of 23 years, age range of 20-27 years; three men, mean age of 24 years, age range of 23-25 years) underwent one MEG session before and two MEG sessions after MR imaging of the brain.
Background And Purpose: Compared with MR imaging, dynamic CT perfusion imaging covers only a fraction of the whole brain. An important assumption is that CT perfusion abnormalities correlate with total ischemic volume. The purpose of our study was to measure the degree of correlation between abnormalities seen on CT perfusion scans and the volumes of abnormality seen on MR diffusion and perfusion images in patients with acute large-vessel stroke.
View Article and Find Full Text PDFUsing event-related functional magnetic resonance imaging we investigated blood oxygen level dependent brain activation in spider phobic and non-phobic subjects while exposed to phobia-related pictures (spiders) and non-phobia-related pictures (snakes and mushrooms). In contrast to previous studies, we show significantly increased amygdala activation in spider phobics, but not in controls, during presentation of phobia-relevant visual stimuli. Furthermore, phobia-specific increased activation was also found in the insula, the orbitofrontal cortex and the uncus.
View Article and Find Full Text PDFTransient cortical blindness is an uncommon but well-known complication following cerebral angiography. One possible cause of this complication is an adverse reaction to contrast agent, resulting in an osmotic disruption of the blood-brain barrier that seems to be selective for the occipital cortex. We report the case of a 16-year-old male patient with cortical blindness after intravenous application of nonionic contrast agent during CT angiography performed because of seizure that was attributed to thrombosis of the basilar artery on the basis of clinical findings.
View Article and Find Full Text PDFWegener granulomatosis is a multisystemic disorder characterized by necrotizing vasculitis that primarily involves the respiratory tract. The orbits, heart, skin, joints, and nervous system are frequently involved. We describe the MR imaging findings of Wegener granulomatosis in the cervical spine and correlate them with the histopathologic features.
View Article and Find Full Text PDFThe aim of this study was to evaluate the sensitivity of multimodal electrophysiological brainstem testing in the diagnosis of clinically suspected reversible ischemic deficits of the brainstem compared with diffusion weighted MR imaging. We investigated 158 consecutive patients presenting with signs of acute brainstem dysfunction. Serial electrophysiological brainstem tests including masseter reflex, blink reflex, masseter inhibitory reflex, AEP, MEP, EOG and the oculoauricular phenomenon were applied.
View Article and Find Full Text PDFUnlabelled: Poland syndrome (PS) (OMIM 173800) is a rare congenital anomaly classically consisting of the combination of unilateral aplasia of the sternocostal head of the major pectoral muscle and an ipsilateral hypoplastic hand with simple syndactyly and short fingers. The aetiology is most probably a vascular disruption sequence of the subclavian arteries. In most cases, PS is sporadic.
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