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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate the validity and accuracy of tissue Doppler imaging (TDI) using a novel balloon phantom, validation of TDI myocardial velocity measurements has been carried out indirectly from conventional M-mode images. However it is not a true and independent gold standard. We described a new TDI validation method by using a specially developed left ventricular balloon model mounted in a water bath and constructed using two pear-shaped balloons. It was connected to a pulsatile flow pump at 8 stroke volumes (50-85 ml/beat). The displacement and velocity of the balloon walls were recorded simultaneously by video imaging and TDI on a GE-Vingmed System Five with a 5 MHz phased array probe at the highest frame rates available. Conventional M-mode and 2-D imaging verified that our balloon model mimicked the shape and wall motion of left ventricle. There was a good correlation and agreement between the maximum video excursion of the anterior and posterior walls of the phantom and the results of the temporal integration of digital distance data by TDI (Anterior wall: r = 0.97, SEE = 0.24 mm, mean +/- s = 0.04 +/- 0.24 mm; Posterior wall: r = 0.95, SEE = 0.22 mm, mean +/- s = 0.03 +/- 0.24 mm). Analysis of the velocity profile by the TDI method showed that the velocity at each measured point was correlated well with the velocity obtained from the video images (Anterior wall: r = 0.97, SEE = 0.30 mm, mean +/- s = -0.04 +/- 0.28 mm; Posterior wall: r = 0.97, SEE = 0.30 mm, mean +/- s = 0.04 +/- 0.28 mm). Our balloon model provided a new independent method for the validation of TDI data. This study demonstrated that the present TDI system is reliable for measuring wall motion distance and velocity.
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PMID:In vitro validation of tissue Doppler left ventricular regional wall velocities by using a novel balloon phantom. 1253 65

In the everyday practice among clinical and etiological classifications for ischemic stroke, the terms strokes in the anterior and posterior cerebral circulation are also in use. The aim of this study was to analyze the frequency of ischemic strokes in the anterior and posterior circulation, their age and sex distribution, risk factors and hospital mortality. In the study it was analyzed 1772 patients with acute ischemic stroke hospitalized at the Department of Neurology Tuzla, Bosnia and Herzegovina, between January 1st 1996 and December 31st 2000. The mean age was 65.5 years (+9.9), 942 (55%) were females. Ischemic strokes for all patients were confirmed with computed tomography, while other data were collected from the standard patients' history charts. Anterior circulation stroke (ACS) had 1408 patients (81.8%), the rest of 314 (18.2%) had posterior circulation stroke (PCS). In the both types females were slightly overrepresented: 784 (56%) in ACS, and 158 (50.5%) in PCS. Moreover, females were significantly older than males: 67 (+9.8) versus 64 (+10) years in ACS (p < 0.001), 67.5 (+10.3) versus 63.5 (+9.2) in PCS (p < 0.001). Hypertension was the major risk factor occurring in 67% patients with ACS and 71 with PCS; heart diseases 54% in the both types, and diabetes in 23% patients with ACS and 20% with PCS. The cortical ischemic lesion was verified in 46% patients with ACS, 41% with PCS; subcortical in 12.5% and 14.5%; and lacunar in 41.5% and 44.5%, respectively. Hospital mortality was 30% (430 patients) for ACS, and 32% (101 patients) for PCS. Hospital mortality was considerably higher among females: 33% versus 28% for ACS (p = 0.03), 38% versus 27% for PCS (p = 0.03). On the basis of our study we can conclude that ischemic strokes in the anterior cerebral circulation are 4/5 of all ischemic strokes at the Department of Neurology Tuzla. Both, anterior and posterior circulation strokes are more frequent in females, witches were in average older than males. The cortical lesion dominated in ACS, and lacunar in PCS. The distribution of risk factors (hypertension, heart diseases, and diabetes) is similar for ACS and PCS, and hospital mortality also; however, mortality rate is higher in females.
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PMID:[Ischemic insult in the anterior and posterior cerebral circulation]. 1452 16

Anterior cerebral artery A1 segment hypoplasia is an uncommon fetal variant of the circle of Willis. The frequency of this congenital variation is 1-13% as derived from angiograms and autopsy reports. Impaired collateral blood flow through the circle of Willis is a recognized risk factor for ischemic stroke. The A1 segment of the anterior cerebral artery is a principal supplier of anterior collateral blood flow. The aim of our study was to determine whether A1 segment hypoplasia may be responsible for acute ischemic stroke. We consecutively examined 280 acute ischemic stroke patients (aged 66.9 +/- 14.2 years). Cerebral magnetic resonance angiography was performed within 72 h of ischemic stroke onset. The overall incidence of A1 variation in our experimental group was 15.0% (n = 42, agenesis/hypoplasia = 18/24), which was statistically higher than in the control group (n = 12). The majority (n = 30, 71.42%) had ipsilateral striatal lacunar infarctions. Based on our results, A1 agenesis/hypoplasia appears to be a risk factor contributing to ischemic stroke, especially to strokes in arteries penetrating the striatal area.
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PMID:Anterior cerebral artery A1 segment hypoplasia may contribute to A1 hypoplasia syndrome. 1726 1

In this retrospective study, we reviewed the charts and collected clinical and radiographic data on children (age range, 1 month to 18 years) with symptoms and radiographic confirmation of ischemic stroke for the period of January 1996 to July 2006. Ninety-four children were enrolled. Eighty-eight had arterial ischemic stroke and six had sinovenous thrombosis. Twenty-nine percent of the children had seizures. Twenty-six percent had diffuse neurological signs and 76% had focal neurological signs. Risk factors included vascular disease (33%), infection (27%), metabolic disorders (18%), trauma (11%), prothrombotic states (13%), cardiac disease (10%), and mitochondrial disease (6%). Ten percent (n=9) had no identifiable cause. Twenty-two percent of the children had more than one risk factor. Anterior territory (70%) was more involved than posterior territory (18%) in arterial ischemic stroke. Unilateral infarctions were more common on the left side (51%) than on the right (24.5%). Neurological deficits were present in 45% (n=34/75) of the children; the most frequent deficit was motor impairment (24%). Seven children (9%) died in the acute stage. There were 12 children (16%) who had recurrent stroke and 8 children (8/12) who had underlying vascular disease. The vascular disease included moyamoya disease (5), CNS lupus (1) and ill-defined vasculopathy (2). The etiology pattern in Taiwan was different from that in Western countries. Vascular disease was a significant risk factor for recurrence in childhood ischemic stroke.
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PMID:Risk factors and outcomes of childhood ischemic stroke in Taiwan. 1757 20

Anterior cerebral artery infarction is uncommon. We studied the topographical distribution of the lesions and the resulting clinical effects for a better understanding of their relationship and the functional outcome. There were 17 patients; the mean age of the cohort was 71 years. There were 10 men and 7 women. Two clinical syndromes were identified in accordance to the two anatomic areas of distribution. The paracentral lobule syndrome (group 1) was characterized by contralateral motor weakness, the leg more than the arm. The second group involved mainly the motor and supplementary motor areas. Beside contralateral weakness, they had a clinical picture of extrapyramidal symptomatology, which was designated as pseudoparkinsonian syndrome (group 2). Sixty percent of the patients in group 2 had bilateral occlusive carotid artery disease compared with 14% in the group 1, and it is likely that the mechanism was artery-to-artery embolism or cardioembolism in this group. In group 1, the lesions were smaller but superficial and it is possible that small emboli from the heart or parent large artery caused the obstruction. The location of the occlusion may be indicative of the stroke mechanism. The pseudoparkinsonian group with extrapyramidal features attributable to involvement of the supplementary motor area had an unfavorable outcome. There was poor correlation between size of the infarct and functional outcome (P=.12) in both groups.
J Stroke Cerebrovasc Dis
PMID:Clinical effects of anterior cerebral artery infarction. 1789 17

Anterior choroidal artery infarction (AChAI) can be the source of aphasia and spatial neglect, but we have no idea of the other possible cognitive disorders. Here, we investigated these disorders in a relatively large cohort of AChAI patients. Twenty patients with relatively recent infarction (left side: 13; mean delay = 47.4 days; 10 men; mean age = 59.6; mean education level, EL = 10.3) were included. We assessed nonspatial attention (alertness, Go Nogo, divided attention and visual vigilance from the computerized test TEA), spatial attention (bell test), language (BDAE) orientation (time, place), short-term memory (forward and backward digit spans, spatial span), executive functioning (WCST, TMT A and B, categorial evocation), delayed memory (Buschke verbal test, Rey figure test), and retrograde memory (questionnaire on famous events). The performance level was compared with that of 20 control subjects matched in age and EL. AChAI patients were impaired in several tests of attention (slowness, increase in omission and error rate), executive functioning (TMT B; categorical evocation) and delayed memory. Conversely, we found preservation of spatial attention, language, orientation, short-term memory, WCST, and retrograde memory. In conclusion, at the secondary phase post-stroke, these patients can present with moderate disorders of attention, memory and executive functioning, which are clearly less severe than what is usually observed following thalamic or cortical lesions.
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PMID:An evaluation of cognitive disorders after anterior choroidal artery infarction. 1857 19

Little is known about anticipatory postural adjustments (APAs) developing when body segments of tiny mass are moved. Thus, APAs in the human upper-limb were investigated during a gentle and small index finger tap (35 mm stroke in 50 ms). This task was fulfilled by ten subjects either with prone or supine hand. EMG was recorded from Flexor Digitorum Superficialis (FDS), the prime mover, and from several upper-limb muscles under slight tonic contraction. Regardless of hand posture, EMG was inhibited in Flexor Carpi Radialis and facilitated in Extensor Carpi Radialis well before the FDS burst. With the prone hand, the prime mover activity was preceded by Biceps inhibition and Triceps facilitation; this effect reverted in sign with the supine hand. A postural reversal was also observed in Anterior Deltoid and Trapezius which were both inhibited with the prone hand. The effect in Trapezius was present only with the unsupported forearm. It is thus demonstrated that a gentle small finger tap produces well-defined anticipatory natural synergies behaving as the most "classical" APAs: (1) they are distributed to several upper-limb muscles creating a postural chain aiming to prevent the effects of the interaction torques generated by the voluntary movement; (2) they change in amplitude according to the level of postural stability and (3) they revert in sign when movement direction is reverted. These results are also corroborated by data obtained from a simple mechanical model simulating finger tapping in a fictive upper-limb. A possible role of APAs in controlling movements' accuracy is also discussed.
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PMID:Anticipatory postural adjustments stabilise the whole upper-limb prior to a gentle index finger tap. 1908 20

Coronary artery bypass grafting (CABG) is one of the options for treating acute myocardial infarction (AMI). However, the mortality of conventional CABG is reported to be high. Therefore, we assessed the outcomes of off-pump coronary artery bypass grafting (OPCAB) in patients with AMI. Between September 2004 and October 2007, 50 patients with AMI, mean age 71.7 years, were operated on. Anterior, inferior and lateral infarctions were observed in 30, 16 and 4 patients, respectively. The time from AMI to operation was <24 hours in 13 patients, <3 days in 5, <7 days in 9, <14 days in 10 and >14 days in 13. Intra-aortic balloon pumping was used in 44% of the patients. Mean number of anastomoses per patient was 4.0. There was no in-hospital mortality. Low output syndrome was observed in 1 patient, and stroke in 2. Ejection fraction of the left ventricle significantly improved after the operation (p<0.01). The graft patency rate was 97.3%. Actuarial survival was 95.9% at 3.5 years. We concluded that OPCAB is a safe and effective procedure with favorable early and midterm survival outcomes in patients with AMI.
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PMID:[Early and mid-term outcome of off-pump coronary artery bypass grafting in patients with acute myocardial infarction]. 1919 84

An increasing number of neuroimaging studies in music cognition research suggest that "language areas" are involved in the processing of musical syntax, but none of these studies clarified whether these areas are a prerequisite for normal syntax processing in music. The present electrophysiological experiment tested whether patients with lesions in Broca's area (N=6) or in the left anterior temporal lobe (N=7) exhibit deficits in the processing of structure in music compared to matched healthy controls (N=13). A chord sequence paradigm was applied, and the amplitude and scalp topography of the Early Right Anterior Negativity (ERAN) was examined, an electrophysiological marker of musical syntax processing that correlates with activity in Broca's area and its right hemisphere homotope. Left inferior frontal gyrus (IFG) (but not anterior superior temporal gyrus - aSTG) patients with lesions older than 4 years showed an ERAN with abnormal scalp distribution, and subtle behavioural deficits in detecting music-syntactic irregularities. In one IFG patient tested 7 months post-stroke, the ERAN was extinguished and the behavioural performance remained at chance level. These combined results suggest that the left IFG, known to be crucial for syntax processing in language, plays also a functional role in the processing of musical syntax. Hence, the present findings are consistent with the notion that Broca's area supports the processing of syntax in a rather domain-general way.
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PMID:Are left fronto-temporal brain areas a prerequisite for normal music-syntactic processing? 2057 Feb 53

This study was conducted to compare the effects of three ankle-foot orthosis (AFO) designs on walking after stroke and determine whether an ankle plantar flexion contracture impacts response to the AFOs. A total of 30 individuals, ranging from 6-215 months post-stroke, were tested in four conditions: shoes only (SH), dorsi-assist/dorsi-stop AFO (DA-DS), plantar stop/free dorsiflexion AFO (PS), and rigid AFO (Rigid). Kinematics, kinetics, and electromyographic (EMG) activity were recorded from the hemiparetic lower extremity while participants walked at a self-selected pace. Gait parameters were compared between conditions and between participants with and without a moderate ankle plantar flexion contracture. All AFOs increased ankle dorsiflexion in swing and early stance. Anterior tibialis EMG was reduced only in the PS AFO. Both PS and Rigid AFOs restricted ankle plantar flexion and increased knee flexion in loading. Peak ankle dorsiflexion in stance and soleus EMG intensity were greatest in the PS AFO. The Rigid AFO tended to restrict dorsiflexion in stance and knee flexion in swing only in participants without a plantar flexion contracture. Individuals without a contracture benefit from an AFO that permits dorsiflexion mobility in stance and those with quadriceps weakness may more easily tolerate an AFO with plantar flexion mobility in loading.
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PMID:Effect of AFO design on walking after stroke: impact of ankle plantar flexion contracture. 2073 32


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