1/42. Callosal disconnection syndrome in a left-handed patient due to infarction of the total length of the corpus callosum.We report on a left-handed patient with an ischemic infarction affecting exclusively the total length of the corpus callosum. This lesion clinically correlated with an almost complete callosal disconnection syndrome as described in callosotomy subjects, including unilateral verbal anosmia, hemialexia, unilateral ideomotor apraxia, unilateral agraphia, unilateral tactile anomia, unilateral constructional apraxia, lack of somesthetic transfer and dissociative phenomena. Despite the patient's left-handedness, his pattern of deficits was similar to the disconnection syndrome found in right-handers. Our report focusses on motor dominance and praxis. We followed-up the improvement in left apraxia and investigated the ability to initiate and learn a new visuo-motor skill. The results permit two tentative assumptions: (1) that the improvement in left apraxia was due to a compensatory increase in ipsilateral proximal muscle control, and (2) that motor dominance, i.e. the competence to initiate and learn a new movement pattern, was hemispherically dissociable from manual dominance in the sense of praxis control.- - - - - - - - - - ranking = 1keywords = hand (Clic here for more details about this article) |
2/42. A pure case of gerstmann syndrome with a subangular lesion.The four symptoms composing Gerstmann's syndrome were postulated to result from a common cognitive denominator (Grundstorung) by Gerstmann himself. He suggested that it is a disorder of the body schema restricted to the hand and fingers. The existence of a Grundstorung has since been contested. Here we suggest that a common psychoneurological factor does exist, but should be related to transformations of mental images rather than to the body schema. A patient (H.P.) was studied, who presented the four symptoms of Gerstmann's syndrome in the absence of any other neuropsychological disorders. MRI showed a focal ischaemic lesion, situated subcortically in the inferior part of the left angular gyrus and reaching the superior posterior region of T1. The cortical layers were spared and the lesion was seen to extend to the callosal fibres. On the basis of an extensive cognitive investigation, language, praxis, memory and intelligence disorders were excluded. The four remaining symptoms (finger agnosia, agraphia, right-left disorientation and dyscalculia) were investigated thoroughly with the aim of determining any characteristics that they might share. Detailed analyses of the tetrad showed that the impairment was consistently attributable to disorders of a spatial nature. Furthermore, cognitive tests necessitating mental rotation were equally shown to be impaired, confirming the essentially visuospatial origin of the disturbance. In the light of this report, the common cognitive denominator is hypothesized to be an impairment in mental manipulation of images and not in body schema.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
3/42. diffusion-weighted magnetic resonance imaging: detection of ischemic injury 39 minutes after onset in a stroke patient.A neurologist witnessed the in-hospital onset of an ischemic stroke in a 71-year-old right-handed male who suddenly developed global aphasia and right hemiplegia. diffusion-weighted magnetic resonance imaging (DWI) 39 minutes after the ictus demonstrated high signals in the left internal carotid artery territory. T1- and T2-weighted images failed to detect this change. magnetic resonance angiography showed occlusions in branches of the left anterior and middle cerebral arteries and an atheromatous stenotic lesion in the ipsilateral proximal internal carotid artery. The patient was treated with intravenous heparin and low molecular dextran solution. Repeated magnetic resonance imagings identified an infarction slightly smaller than the abnormality demonstrated by the initial DWI. DWI detects hyperacute ischemic injury within 1 hour of symptom onset in human ischemic stroke.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
4/42. Apraxia differs in corticobasal degeneration and left-parietal stroke: A case study.Corticobasal degeneration (CBD) is a progressive disorder characterized by both cortical and basal ganglia dysfunction such as asymmetrical apraxia, and akinetic rigidity, involuntary movements, and cortical sensory loss. Although apraxia is a key finding for the differential diagnosis of CBD, it has not been determined whether the features of apraxia seen in subjects with CBD are similar to those features exhibited by subjects with left-hemisphere damage from stroke. Therefore, for both clinical purposes and in order to better understand the brain mechanisms that lead to apraxia in CBD, we studied praxis in a patient with CBD and compared him to patients who are apraxic from left-parietal strokes. We used three-dimensional movement analyses to compare the features of apraxic movement. This subject with CBD was a dentist whose initial complaint had been that he "forgot" how to use his tools in the mouths of his patients. Analyses were performed on the trajectories made when using a knife to actually slice bread, and when repetitively gesturing slicing made to verbal command. Movements of the left hand, wrist, elbow, and shoulder were digitized in 3-D space. Although the CBD subject was clearly apraxic, the features of his apraxia differed markedly from those of the subjects with lesions in the left parietal lobe. For movements to command, the CBD subject showed joint coordination deficits, but his wrist trajectories were produced in the appropriate spatial plane, were correctly restricted to a single plane, and, like control subjects, were linear in path shape. However, when he was actually manipulating the tool and object, all of these aspects of his trajectories became impaired. In contrast, the deficits of the apraxic subjects with left-parietal damage were most pronounced to verbal command with their movements improving slightly although remaining impaired during actual tool and object manipulation. Unlike patients with parietal strokes, patients with CBD have degeneration in several systems and perhaps deficits in these other areas may account for the differences in praxic behavior.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
5/42. Altered hemodynamic responses in patients after subcortical stroke measured by functional MRI.BACKGROUND AND PURPOSE: blood oxygenation level-dependent (BOLD) functional MRI (fMRI) is a promising method for defining brain recovery after stroke quantitatively. Applications thus far have assumed that the BOLD hemodynamic response in patients after stroke is identical to that in healthy controls. However, because of local vascular compromise or more diffuse vascular disease predisposing to infarction, this assumption may not be justified after stroke. We sought to test whether patients who have suffered a lacunar stroke show BOLD fMRI response characteristics identical to those of healthy controls. methods: We measured the BOLD fMRI signal time course in the sensorimotor cortex contralateral to the affected hand with finger- or hand-tapping tasks for minimally or mildly impaired right-handed patients (n=12) after lacunar strokes causing limb weakness and for healthy controls (n=20). RESULTS: With a right-handed sequential finger-tapping task, the rate of rise and maximum increase of the BOLD signal in the contralateral sensorimotor cortex were > 30% lower (P< or =0.01) in the stroke patients. Similar relative decreases were found for the same task performed with the left hand. These changes were found in patients both in the hemisphere affected by stroke and in the unaffected hemisphere, suggesting that the BOLD fMRI time course differences observed arise from a diffuse functional pathology. The difference between patients and controls is not a result of age alone, since differences were not found between the younger (n=10; aged 22 to 38 years) and the older (n=10; aged 56 to 83 years) healthy controls. The effect also does not seem to be dependent on the specific hand movement task used. CONCLUSIONS: The magnitude of the BOLD fMRI response can be reduced in stroke patients even if infarcts do not involve the cortex. This may be a consequence of the stroke, but the observation that the BOLD signal time course is similar in the affected and unaffected hemispheres suggests that it also could result from preexisting pathophysiological changes in the cerebral microvasculature.- - - - - - - - - - ranking = 0.85714285714286keywords = hand (Clic here for more details about this article) |
6/42. Isolated corpus callosal infarction secondary to pericallosal artery disease presenting as alien hand syndrome.Two patients are described with the callosal type of alien hand syndrome. Both presented with abnormal feelings in the left upper limb and intermanual conflict without clinical evidence of callosal apraxia or frontal lobe dysfunction such as motor deficit or reflexive grasping. Imaging studies disclosed subacute infarction in the body and splenium of the corpus callosum due to pericallosal artery disease. These patients were unique in their presentation as a callosal type of alien hand syndrome secondary to ischaemic stroke.- - - - - - - - - - ranking = 8101.5759616726keywords = alien hand syndrome, hand syndrome, alien hand, alien, hand (Clic here for more details about this article) |
7/42. Cerebral, myocardial and cutaneous ischemic necrosis associated with calcific emboli from aortic and mitral valve calcification in a patient with end-stage renal disease.We report the case of a 57-year-old diabetic male with chronic renal failure who developed secondary hyperparathyroidism and calcification of mitral and aortic valves and interatrial septum. Multiple ischemic lesions developed in the skin of hands, feet and penis, and in the brain, and these were presumed to be due to septic emboli from cardiac valvular infective endocarditis. Multiple blood cultures were negative, however, and despite antibiotic therapy the patient expired. autopsy (limited to trunk) demonstrated multiple calcific emboli in the heart and spleen, apparently derived from the prominent calcific deformities in the aortic and mitral valves. These were associated with acute and organizing myocardial infarcts and acute splenic infarcts, suggesting that the multiple ischemic lesions in the brain were also due to calcific emboli. A possible contributory component of infective endocarditis, however, was indicated by postmortem cultures of aortic and mitral valves positive for enterococcus faecium. Calcific embolism is a rarely recognized but potentially lethal complication of end-stage renal disease, and the clinical diagnosis and the preventive therapeutic options for the control of the product of calcium and phosphate and/or parathyroidectomy should be considered.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
8/42. Post-apoplectic reorganization of cortical areas processing passive movement and tactile stimulation--a neuromagnetic case study.magnetoencephalography (MEG) was used in a patient with right centro-parietal stroke to investigate the cortical processing of tactile pneumatic stimulation and passive movement of the impaired left and unaffected right-hand index finger. Source localization of somatosensory evoked magnetic fields (SEF) recorded 2 weeks after infarction demonstrated a spatial displacement of the contralateral SI generators in the affected hemisphere. The distance between SI sources activated by either stimulation technique was noticeably enlarged in comparison to the left hemisphere and to previous data from 12 healthy subjects. Follow-up MEG after 6 months revealed a closer spatial arrangement of the two modality-specific SEF generators and a diminution of the interhemispheric asymmetry of proprioception-related SI sources. The topographical alterations were accompanied by clear clinical improvement of both joint position sense and tactile sensation. The occurrence of ipsilateral SI activity following passive movement of only the impaired index finger might suggest a disinhibition of subthreshold, transcallosal excitatory pathways.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
9/42. Delayed ischemic deficit after resection of a large intracranial dermoid: case report and review of the literature.OBJECTIVE AND IMPORTANCE: A unique case of delayed ischemic deficit after resection of a large intracranial dermoid is presented. CLINICAL PRESENTATION: A 23-year-old woman, 36 hours after the uneventful gross total resection of a large intracranial dermoid cyst, slowly developed a progressive mixed aphasia and right hemiparesis. magnetic resonance imaging and magnetic resonance angiography revealed small infarcts of the left putamen and temporal-occipital junction and a vasospastic tapering of the left M1 segment. INTERVENTION: Angiography confirmed severe vasospastic tapering of the left M1 and M2 segments. Endovascular treatment successfully restored flow in the left superior division. However, the initial attempt at low-pressure dilation of the inferior division led to vessel rupture. Seven months after reoperation for emergent trapping of the M1 segment, the patient made an excellent recovery, with only mild right-hand incoordination. CONCLUSION: Ruptured dermoid cysts are a risk for early and delayed cerebral ischemia, and endovascular treatment of dermoid-encased vessels may carry a higher risk for rupture.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
10/42. Thalamic stuttering: a distinct clinical entity?A 38-year-old right-handed male with no history of speech or language problems presented with neurogenic stuttering following an ischaemic lesion of the left thalamus. He stuttered severely in propositional speech (conversation, monologue, confrontation naming, and word retrieval) but only slightly in non-propositional speech (automatic speech, sound, word and sentence repetition, and reading aloud). It is suggested that thalamic stuttering may constitute a distinct clinical entity.- - - - - - - - - - ranking = 0.14285714285714keywords = hand (Clic here for more details about this article) |
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