1,720,971 research outputs found
Dropped-head syndrome due to steroid responsive focal myositis: A case report and review of the literature
No full textIsolated severe weakness of the paraspinal musculature, either at the cervical level leading to a "dropped head syndrome" or at the thoracic level leading to a "bent-spine syndrome", is a rare disorder. Etiologically it may be present in a variety of neurological diseases including Parkinson's disease, multiple system atrophy, neuromuscular or motor neuron diseases, as well as non-inflammatory, inflammatory, dystrophic or metabolic myopathies. We present a previously healthy 74-year-old man with a 2-month history of progressive difficulty in lifting his chin off his chest. Magnetic resonance imaging and skeletal muscle biopsy revealed an isolated myositis of the neck extensor and trapezius muscles, which responded well to steroid therapy. This case and other rare reports obtained from a systematic review of the literature indicate that in a subgroup of patients "dropped head syndrome" or "bent spine syndrome" is caused by a myositis, which emphasizes the necessity to obtain a MRI examination, as well as a muscle biopsy to diagnose this potentially treatable disease. (c) 2007 Elsevier B.V. All rights reserved
Atypical botulism sparing palsy of extraocular muscles
No full textRecent studies of patients with botulism found ophthalmoplegia as a characteristic clinical sign. Here we illustrate a very rare case of atypical foodborne botulism with multiple bilateral cranial nerve palsies sparing palsy of extraocular muscles. Therefore, the classical diagnostic pentad of botulism (dry mouth, nausea, vomiting, dysphagia, diplopia, fixed dilated pupils) may be of limited sensitivity in single cases
Vertebrobasilar insufficiency due to right aortic arch with isolation of the left subclavian artery
No full textAtypical botulism sparing palsy of extraocular muscles
No full textRecent studies of patients with botulism found ophthalmoplegia as a characteristic clinical sign. Here we illustrate a very rare case of atypical foodborne botulism with multiple bilateral cranial nerve palsies sparing palsy of extraocular muscles. Therefore, the classical diagnostic pentad of botulism (dry mouth, nausea, vomiting, dysphagia, diplopia, fixed dilated pupils) may be of limited sensitivity in single cases
Effects of age and symptom status on silent ischemic lesions after carotid stenting with and without the use of distal filter devices
No full textBACKGROUND AND PURPOSE: The routine use of distal filter devices during carotid angioplasty and stent placement (CAS) is controversial. The aim of this study was to analyze their effects on the incidence of new diffusion-Weighted imaging (DWI) lesions as surrogate markers for stroke in important subgroups. MATERIALS AND METHODS: DWI was performed immediately before and after CAS in 68 patients with and 175 without protection, and patients were further subdivided according to their age or symptom status. RESULTS: The proportion of patients with new ipsilateral DWI lesion(s) was significantly lower after protected versus unprotected CAS (52% versus 68%), as well as in symptomatic patients (56% versus 74%) or those at or younger than 75 years of age (46% versus 67%, all P < .05). Similarly, the total number of lesions was significantly lower after protected versus unprotected CAS (median, 1; interquartile range [IQR], 0-2; versus median, 1; IQR 0-4.75) and in symptomatic patients (median, 1; IQR, 0-3; versus median, 2; IQR, 0-6) or those at or younger than 75 years of age (median, 0; IQR, 0-2; versus median, 1; IQR, 0-4; all P < .05). In contrast, for asymptomatic patients (48% versus 52%; P = .8; median, 0; IQR, 0-2; versus median, 1; IQR, 0-2.5; P = .6) or those older than 75 years of age (73% versus 69%; F = .7; median, 1; IQR, 0-4; versus median, 1.5; IQR, 0-5.75, P = .6), the proportion of patients with new lesion(s) and the total number of these lesions were not significantly different between protected and unprotected CAS. CONCLUSIONS: The use of distal filter devices generally reduces the incidence of new DWI lesions, however, this beneficial effect might not necessarily pertain to older and asymptomatic patients
Effects of physiological aging and cerebrovascular risk factors on the hemodynamic response to brain activation: a functional transcranial Doppler study
No full textThe influence of the vascular system on the coupling of cerebral blood flow (CBF) to focal brain activation during aging is incompletely understood. Using functional transcranial Doppler sonography and a hypercapnic challenge as a marker of intact cerebral vasoreactivity, we determined CBF velocity (CBFV) changes in response to a language and arithmetic task in a group of 43 healthy young subjects (mean age 32 +/- 8.6 years), 18 healthy old subjects (mean age 64 +/- 9.8 years) and 29 old subjects with risk factors for an atherosclerosis (mean age 69 +/- 8.4 years). Despite a similar performance during the cognitive tasks the CBFV changes were significantly lower in the group of old subjects with vascular risk factors compared with the healthy young and old subjects. Similarly, the CBFV changes during hypercapnia were significantly lower in the group of old subjects with vascular risk factors compared with the healthy young and old subjects. In contrast, both cognitive tasks and hypercapnia produced comparable CBFV changes in the group of healthy young and old subjects. These results suggest that the hemodynamic response to neuronal activation is unaffected by aging alone, whereas the presence of cardiovascular risk factors significantly diminishes the capability of cerebral vessels to react to vasodilating stimuli
Functional significance of age-related differences in motor activation patterns
No full textRecent functional MRI (fMRI) studies have revealed an increased task-related activation in older subjects during a variety of cognitive or perceptual tasks, which may signal beneficial compensatory activity to counteract structural and neurochemical changes associated with aging. Under the assumption that incremental movement rates are associated with an increased functional demand on the motor system, we used fMRI and acoustically paced movements of the right index finger at six different frequencies (2.0, 2.5, 3.0, 4.0, 5.0 and 6.0 Hz) to investigate the behavioral significance of additionally recruited brain regions in a group of healthy, older subjects (mean age 66 8 years) compared with a group of young (mean age 23 7 years) subjects. The actual tapping frequency (F(1,14) = 0.049, P = 0.829), the tapping interval (F(1,14) = 0.043, P = 0.847), and the error rates (F(1,14) = 0.058, P = 0.743) did not differ significantly between both groups, whereas there was a significant increase in reaction time in the older subjects (F(1,14) = 281.786, P <= 0.001). At all frequencies, the older subjects demonstrated significant overactivation within the ipsilateral sensorimotor and premotor cortex. However, we did not observe an increased age-related overactivation during higher movements rates in these or other motor regions. Moreover, the magnitude of the hemodynamic response in overactivated regions remained constant across all frequencies. In contrast to cognitive tasks, these findings indicate that an age-related overactivation within the motor system is not related to the functional demand and does not necessarily reflect reorganization to compensate for the neurobiological changes of aging. (c) 2006 Elsevier Inc. All rights reserved
The role of the unaffected hemisphere in motor recovery after stroke
No full textThe contribution of the ipsilateral (nonaffected) hemisphere to recovery of motor function after stroke is controversial. Under the assumption that functionally relevant areas within the ipsilateral motor system should be tightly coupled to the demand we used fMRI and acoustically paced movements of the right index finger at six different frequencies to define the role of these regions for recovery after stroke. Eight well-recovered patients with a chronic striatocapsular infarction of the left hemisphere were compared with eight age-matched participants. As expected the hemodynamic response increased linearly with the frequency of the finger movements at the level of the left supplementary motor cortex (SMA) and the left primary sensorimotor cortex (SMC) in both groups. In contrast, a linear increase of the hemodynamic response with higher tapping frequencies in the right premotor cortex (PMC) and the right SMC was only seen in the patient group. These results support the model of an enhanced bihemispheric recruitment of preexisting motor representations in patients after subcortical stroke. Since all patients had excellent motor recovery contralesional SMC activation appears to be efficient and resembles the widespread, bilateral activation observed in healthy participants performing complex movements, instead of reflecting maladaptive plasticity. Hum Brain Mapp 31:1017-1029, 2010. (C) 2010 Wiley-Liss, Inc
The contribution of white and gray matter differences to developmental dyslexia: Insights from DTI and VBM at 3.0T
No full textDevelopmental dyslexia is one of the most common neuropsychological disorders in children and adults. Only few data are available on the pathomechanisms of this specific dysfunction, assuming - among others - that dyslexia might be a disconnection syndrome of anterior and posterior brain regions involved in phonological and orthographic aspects of the reading process, as well as in the integration of phonemes and graphenes. Therefore, diffusion tensor imaging(DTI)and voxel-based morphometry (VBM) were used to verify the hypothesis of altered white and gray matter structure in German dyslexic adults. DTI revealed decreased fractional anisotropy (FA) in bilateral fronto-temporal and left temporo-parietal white matter regions (inferior and superior longitudinal fasciculus). Significant correlations between white matter anisotropy and speed of pseudoword reading were found. In dyslexics, gray matter volumes (as measured by VBM) were reduced in the superior temporal gyrus of both hemispheres. So far, our results, based on a combined analysis of white and gray matter abnormalities, provide exceedingly strong evidence for a disconnection syndrome or dysfunction of cortical areas relevant for reading and spelling. Thus, we suggest that this imbalance of neuronal communication between the respective brain areas might be the crucial point for the development of dyslexia. (c) 2008 Elsevier Ltd. All rights reserved
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