Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe the incidence and natural history of four clinically identifiable subgroups of cerebral infarction in a community-based study of 675 patients with first-ever stroke. Of 543 patients with a cerebral infarct, 92 (17%) had large anterior circulation infarcts with both cortical and subcortical involvement (total anterior circulation infarcts, TACI); 185 (34%) had more restricted and predominantly cortical infarcts (partial anterior circulation infarcts, PACI); 129 (24%) had infarcts clearly associated with the vertebrobasilar arterial territory (posterior circulation infarcts, POCI); and 137 (25%) had infarcts confined to the territory of the deep perforating arteries (lacunar infarcts, LACI). There were striking differences in natural history between the groups. The TACI group had a negligible chance of good functional outcome and mortality was high. More than twice as many deaths were due to the complications of immobility than to direct neurological sequelae of the infarct. Patients in the PACI group were much more likely to have an early recurrent stroke than were patients in other groups. Those in the POCI group were at greater risk of a recurrent stroke later in the first year after the index event but had the best chance of a good functional outcome. Despite the small anatomical size of the infarcts in the LACI group, many patients remained substantially handicapped. The findings have important implications for the planning of stroke treatment trials and suggest that various therapies could be directed specifically at the subgroups.
 ...
PMID:Classification and natural history of clinically identifiable subtypes of cerebral infarction. 167 78

The validity of a clinical classification system was assessed for subtypes of cerebral infarction for use in clinical trials of putative stroke therapies and clinical decision making in a population based stroke register (n = 536) compiled in Perth, Western Australia in 1989-90. The Perth Community Stroke Project (PCSS) used definitions and methodology similar to the Oxfordshire Community Stroke Project (OCSP) where the classification system was developed. In the PCSS, 421 cases of cerebral infarction and primary intracerebral haemorrhage (PICH), confirmed by brain imaging or necropsy, were classified into the subtypes total anterior circulation syndrome (TACS), partial anterior circulation syndrome (PACS), lacunar syndrome (LACS), and posterior circulation syndrome (POCS). In this relatively unselected population, relying exclusively on LACS for a diagnosis of PICH had a very low sensitivity (6%) and positive predictive value (3%). Comparison of the frequencies and outcomes (at one year after the onset of symptoms) for each subgroup of first ever cerebral infarction in the PCSS (n = 248) with the OCSP (n = 543) registers showed uniformity only for LACI. For example, there were 27% of cases of TACI in the PCSS compared with 17% in the OCSP (difference = 10%; 95% confidence interval (95% CI) 4% to 16%) and 15% of cases in the PCSS compared with 24% in the OCSP were POCI (difference = 9%; 95% CI 3% to 15%). Case fatalities and long-term handicap across the subgroups were not significantly different between studies, but the frequencies of recurrent stroke were significantly greater for POCI in the OCSP compared with the PCSS. Although this classification system defines subtypes of stroke with different outcomes, simple clinical measures-level of consciousness, paresis, disability, and incontinence at onset-are more powerful predictors of death or dependency at one year. It is concluded that simple clinical measures that reflect the severity of the neurological deficit should complement this classification system in clinical trials and practice.
 ...
PMID:Validation of a clinical classification for subtypes of acute cerebral infarction. 793 76

Between 1 January 1989 and 31 December 1990 568 consecutive patients were admitted to our unit for ischemic stroke (defined on clinical criteria and with CT or MR evidence of ischemic areas or exclusion of hemorrhage or tumor). The interval between onset of symptoms and arrival in hospital was under 6 h in 270 cases (47.5%). We classified our population according to the clinical criteria proposed by Bamford et al. by subgroup as follows: LACI (27.5%); PACI (24.5%); TACI (30.6%); POCI (17.4%). The mortality in our population was 10.9%. The distribution of the risk factors considered was: hypertension in 387 cases (67%), diabetes in 158 cases (27.8%), NVAF in 95 cases (16.7%). Our data show that about a half of all patients with ischemic stroke can expect to receive treatment at the acute stage.
 ...
PMID:Before M.A.S.T.-I: analysis of the population of a participating center. 847 53

In this review, the clinical utility of echoplanar techniques in MRI of the brain is discussed. Comparison of high-resolution EPI with SE/turbo-SE shows high image quality of EPI in the supratentorial brain. In the infratentorial region, however, susceptibility artifacts limit image quality. For the assessment of neuronal brain activation utilizing the intrinsic contrast of blood (BOLD), EPI has definite advantages over other techniques of functional MRI. Due to its superior temporal resolution and multislice capabilities, EPI allows for analysis of complex neuronal activation patterns. Diffusion imaging benefits from the lack of bulk motion artifacts and serves primarily to detect early stroke. Three methods of perfusion imaging (rel. blood volume, rel. blood flow) are discussed: the susceptibility artifact method (T2*), the relaxitivity method (T1), and the signal-labelling technique (STAR). Perfusion imaging may have a clinical impact in the assessment of brain tumors and cerebral ischemia.
 ...
PMID:[Echo-planar imaging of the brain]. 858 33

Rapid changes in the apparent diffusion coefficient of water following brain ischemia have been extensively studied using echo planar diffusion imaging at low fields (2.0 T). There is a desire to perform these studies at higher fields (> 3.0 T) where the benefits of improved signal-to-noise can be exploited. Unfortunately, EPI diffusion is technically difficult to implement at high fields because of large magnetic susceptibility effects. This article demonstrates the feasibility of employing a line-scan diffusion protocol for ADCw measurements in stroke. The technique was applied on a 4.0 T system to monitor the decline in ADCw following the induction of focal cerebral ischemia in rat. ADCw data were acquired every 15 s with 10 b-values or every 22.5 s with 15 b-values, with a cubic spatial resolution of 1.5 mm. The results demonstrate that estimates of ADCw can be acquired with coefficients of variation under 3.0%, and with a combination of spatial and temporal resolution comparable to that previously reported for EPI.
 ...
PMID:The application of diffusion-weighted line-scanning for the rapid assessment of water ADC changes in stroke at high magnetic fields. 926 65

We have prospectively studied all cholecystectomies performed in one year in our clinic in two groups: 190 cases performed laparoscopically and 98 open. We used standardized records and the EPI 5 program on an IBM compatible computer. There were no significant differences between groups regarding weight, sex and proportion of cases with acute cholecystitis. There were however major differences regarding age, type of habitat, ASA score and association with acute pancreatitis, obstructive jaundice and angiocholitis. Conversion of laparoscopic cholecystectomy to open procedure was imposed in 17 cases (not included in statistical analysis) due to technical difficulties (12 cases), haemorrhagic accidents (6 cases), injury of the common bile duct (1 case), stones lost in the abdominal cavity (3 cases), local peritonitis (5 cases). Laparoscopic cholecystectomy lasted a mean of 74 minutes. We encountered 3 specific complications: one CBD injury recognized intraoperatively and managed by Kehr's procedure (one CBD injury in the open cholecystectomy group), one small bowel perforation and one of biloma. Mortality averaged 0.5% in the LC group (one case of late postoperative stroke considered not related to the procedure) and 1% in the open cholecystectomy group. The hospital admission period was significantly reduced in the LC group (5 days vs. 12 days). LC appears as a safe procedure with a low complication rate. Conversion to open procedure is not a complication. Our study recommend LC as the method of choice in the treatment of gallbladder lithiasis.
 ...
PMID:[The value of laparoscopic cholecystectomy in the treatment of gallbladder pathologies]. 945 51

Diffusion-weighted (DWI) echo-planar (EPI) MRI has been used for imaging acute ischaemic stroke. We used DWI and conventional spin-echo (SE) MRI to study the dynamics of ischaemic human stroke. We examined 30 patients (mean age 57.5 years, range 27-82 years, median 57 years) with a diagnosis of stroke. They were examined in the acute (120 min to 47 h, mean 15.3 h), subacute (8 days) and chronic (2-3 months) stages of ischaemia using clinical scores and MRI. Imaging was performed on an 1.5-T imager. Anisotropic DWI with diffusion gradients in all three axes, an isotropic tensor trace pulse DWI sequence and SE MRI were used. In all patients both DWI sequences showed a decrease in the apparent diffusion coefficient (ADC) in the acute stage, even when SE images did not reveal signal abnormalities. Clinical features correlated with lesion site but not size. The ADC was initially 19.6-43% less than that of nonischaemic tissue and increased to normal after 7 days in conventionally treated patients and after 2-5 days in patients who underwent intra-arterial fibrinolysis. In the chronic stage the ADC rose by up to 254.4 %. In patients who did not undergo fibrinolysis DWI changes correlated with the final infarct size (P<0.05). It was possible to differentiate acute from chronic ischaemic lesions. We conclude that DWI is a sensitive and practicable tool for detecting early cerebral ischaemia. It is possible to predict in the acute stage the final size of an infarct. DWI may be helpful for clinical decisions and for monitoring therapy.
 ...
PMID:Diffusion-weighted imaging in ischaemic stroke: a follow-up study. 1077 39

The sensitivity of diffusion-weighted MR imaging to detect a lesion within 6 hours of stroke onset was approximately 90%. The false negative results were usually small lesions (1 ml), were seen early, and were usually located in the brain stem. The specificity of this technique was nearly 100% when it was used correctly. The volume and the value of the apparent diffusion coefficient of the detected lesions provided prognostic information. After injection of a contrast agent (perfusion imaging), a time series of volumes were obtained using a T2* sensitive gradient echo EPI sequence. Hemodynamic perturbations of the cerebral parenchyma could be detected as well as the type of perturbation in the lesion. A map representing the mean transit time for each voxel was used to define the maximum volume of the perturbation. A hemodynamic penumbra was defined to be when this volume was larger than the volume detected on the diffusion images. The quantitative measure of cerebral blood flow could predict the irreversibility of the lesions when the value was below 18 ml/min/100g, and the extension of the ischemia in the penumbra zone when the value was below a threshold of 30 ml/min/100g.
 ...
PMID:[Diffusion- and perfusion-weighted MR imaging during the hyperacute phase of stroke]. 1091 3

The preliminary results of MR echoplanar diffusion-weighted imaging (EPI DWI) in patients with stroke are presented. Twelve patients (5 females, 7 males) aged 36-78 years (mean 63.8) were examined by 2T system. No focal lesions were found in the acute phase of stroke on T1-weighted images. Narrowing of sulci in the region of stroke was the only abnormal finding. Focal hyperintense lesions were shown on PD and T2-weighted images in 50% of patients in the acute phase, 7 hours after the onset of clinical symptoms. On EPI diffusion-weighted images focal decrease of apparent diffusion coefficient (ADC) was observed in all cases of the acute phase of stroke after 3 hours. EPI DWI allows for earliest detection of ischaemic lesions in brain tissue. The method is especially useful in characterisation of the acute phase of stroke and shows its evolution thanks to the use of ADC.
 ...
PMID:[The usefulness of the method of planar diffusion echo imaging (EPI DWI) in the diagnosis of cerebral ischemia]. 1096 19

Diffusion-weighted imaging(DWI) has been demonstrated to be valuable for assessment of ischemic stroke patients. The aim of this study is to evaluate clinical usefulness of DWI in the diagnosis of transient ischemic attack(TIA). Nineteen patients with symptoms of TIA were studied. DWI was taken with 1.5 Tesla MRI system using spin echo EPI sequence. Seven patients revealed areas of hyperintensity (brightness) on DWI and of hypointensity on apparent diffusion coefficient(ADC) maps relative to normal brain. As the duration of TIA symptom elongated, the percentage of patients with DWI abnormalities became higher. DWI enabled to detect areas of hyperintense lesion in all three patients as early as 3 hours after the onset, while conventional T2 weighted imaging showed in one. All the DWI abnormalities were irreversible in spite of the complete recovery from TIA. DWI is an useful technique for the detection of responsible lesions in TIA. However, TIA cannot be ruled out even if DWI does not demonstrate any abnormal signals.
 ...
PMID:[Usefulness of diffusion-weighted MRI in the diagnosis of transient ischemic attacks]. 1107 Sep 24


1 2 3 4 5 6 Next >>