***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background and Purpose — Transcranial color-coded duplex sonography ( TCCS ) allows bedside imaging of intracranial hemodynamics and parenchymal structures . It provides reliable information regarding midline shift ( MLS ) in space-occupying hemispheric stroke . We studied the value of MLS measurement to predict fatal outcome at different time points after stroke onset . Methods — Forty-two patients with acute , severe hemispheric stroke were enrolled .  Cranial computed tomography ( CCT ) and extracranial duplex sonography were performed on admission . TCCS was carried out 8±3 , 16±3 , 24±3 , 32±3 , and 40±3 hours after stroke onset . Lesion size was determined from follow-up CCT . Results — Twelve patients died as the result of cerebral herniation ( group 1 ) ; 28 survived ( group 2 ) . Two patients received decompressive hemicraniectomy and were therefore excluded from further evaluation . MLS was significantly higher in group 1 as early as 16 hours after onset of stroke . Specificity and positive predictive values for death caused by cerebral herniation of MLS ≥2.5 , 3.5 , 4.0 , and 5.0 mm after 16 , 24 , 32 , and 40 hours were 1.0 . Conclusions — TCCS helps to estimate outcome as early as 16 hours after stroke onset and thus facilitates identification of patients who are unlikely to survive without decompressive craniectomy . Because of its noninvasive character and bedside suitability , sonographic monitoring of MLS might be a useful tool in management of critically ill patients who can not undergo repeated CCT scans BACKGROUND AND PURPOSE Malignant , space-occupying supratentorial ischemic stroke is characterized by a mortality rate of up to 80 % . Several reports indicate a beneficial effect of hemicraniectomy in this situation . However , whether and when decompressive surgery is indicated in these patients is still a matter of debate . METHODS In an open , prospect i ve trial we performed hemicraniectomy in 63 patients with acute complete middle cerebral artery infa rct ion . Initial clinical presentation was assessed by the  Sc and inavian  Stroke Scale ( SSS ) and the Glasgow Coma Scale ( GCS ) . All survivors were reexamined 3 months after surgical decompression , with the clinical evaluation grade d according to the Rankin Scale ( RS ) and Barthel Index ( BI ) . We analyzed the influence of early decompressive surgery ( < 24 hours after symptom onset , based on clinical status at admission and initial CT findings ) versus late surgery ( > 24 hours after first reversible signs of herniation ) on mortality , functional outcome , and the length of time of critical care therapy was needed . RESULTS In total , 46 patients ( 73 % ) survived . Despite complete hemispheric infa rct ion , no survivor suffered from complete hemiplegia or was permanently wheelchair bound . In patients with speech-dominant hemispheric infa rct ion ( n=11 ) , only mild to moderate aphasia was present . The mean BI score was 65 , and RS score revealed severe h and icap in 13 % of the patients . In 31 patients with early decompressive surgery , mortality was 16 % and BI score 68.8 . Early hemicraniectomy led to a significant reduction in the length of time critical care therapy was needed ( 7.4 versus 13.3 days , P<0.05 ) . CONCLUSIONS In general , the outcome of patients treated with craniectomy in severe ischemic hemispheric infa rct ion was surprisingly good . In addition , early decompressive surgery may further improve outcome in these patients BACKGROUND AND PURPOSE Early identification of acute stroke patients at risk of fatal brain swelling  is necessary to facilitate implementation of aggressive therapies . Initial clinical , laboratory , and CT characteristics that may be used as selection criteria were analyzed to determine predictors of herniation and neurological death . METHODS Data from the placebo arm of the Lubeluzole-International-9 trial were review ed to identify patients with fatal brain edema . Early clinical , laboratory , and radiographic parameters were evaluated in a case-control design . Initial CT scans were analyzed for early ischemic abnormalities by 2 blinded investigators . RESULTS Twenty-three patients died  from brain swelling  , with minimum baseline National Institutes of Health Stroke Scale ( NIHSS ) scores of 20 ( n=12 ; mean , 23.2+/-1.8 ) with left and 15 ( n=11 ; mean , 17.6+/-2.2 ) with right hemispheric infa rct ions ( P=0 . 0001 ) . A sample of 112 subjects with comparably severe strokes , but who did not die from brain swelling , was selected from the remaining population according to the same NIHSS scores . Among clinical and laboratory characteristics , nausea/vomiting within 24 hours after onset ( odds ratio [ OR ] , 5.1 ; 95 % CI , 1.7 to 15.3 ; P=0.003 ) and 12-hour systolic blood pressure > /=180 mm Hg ( OR , 4.2 ; 95 % CI , 1.4 to 12.9 ; P=0.01 ) were independently associated with fatal brain swelling . Among radiographic factors , only hypodensity of > 50 % of the middle cerebral artery territory on initial CT scan was an independent predictor ( OR , 6.1 ; 95 % CI , 2.3 to 16.6 ; P=0.0004 ) . CONCLUSIONS Patients with baseline NIHSS score > /=20 with left or > /=15 with right hemispheric infa rct ions within 6 hours of symptom onset who also have nausea/vomiting or > 50 % middle cerebral artery territory hypodensity are at high risk for developing fatal brain swelling BACKGROUND AND PURPOSE To predict malignant course in patients with large middle cerebral artery ( MCA ) infa rct ion , we combined PET imaging and neuromonitoring , including microdialysis . METHODS Thirty-four patients with stroke of > 50 % of the MCA territory in early cerebral CT scan were included . Probes for microdialysis and measurement of intracranial pressure and tissue oxygen pressure ( Pto2 ) were placed into the ipsilateral frontal lobe . PET was performed with 11C-flumazenil to assess CBF and irreversible neuronal damage . RESULTS PET measurements within 24 hours after stroke showed larger volumes of ischemic core ( mean , 144.5 versus 62.2 cm3 ) and larger volumes of irreversible neuronal damage ( 157.9 versus 47.0 cm3 ) in patients with malignant course ( ie , edema formation with midline shift ) than in patients with benign course . Mean cerebral blood flow values within the ischemic core were significantly lower and the volume of the ischemic penumbra was smaller in the malignant than in the benign group . In patients with malignant course , cerebral perfusion pressure dropped to < 50 to 60 mm Hg 22 to 72 hours ( mean , 52.0 hours ) after onset of symptoms ; subsequently , Pto2 dropped and glutamate increased , indicating secondary ischemia . Maximal changes in the monitored variables reached significant levels for glutamate , aspartate , GABA , glycerol , lactate-to-pyruvate ratio , hypoxanthine , intracranial pressure , cerebral perfusion pressure , and Pto2 . CONCLUSIONS PET allowed prediction of malignant MCA infa rct ion within the time window suggested for hemicraniectomy . Neuromonitoring helped to classify the clinical courses by characterizing pathophysiological sequelae of malignant edema formation . In contrast to PET , however , it did not predict fatal outcome early enough for successful implementation of invasive therapies BACKGROUND In laboratory animals , cerebral ischaemia is worsened by hyperthermia and improved by hypothermia . Whether these observations apply to human beings with stroke is unknown . We therefore examined the relation between body temperature on admission with acute stroke and various indices of stroke severity and outcome . METHODS In a prospect i ve and consecutive study 390 stroke patients were admitted to hospital within 6 h after stroke ( median 2.4 h ) . We determined body temperature on admission , initial stroke severity , infa rct size , mortality , and outcome in survivors . Stroke severity was measured on admission , weekly , and at discharge on the Sc and inavian Stroke Scale ( SSS ) . Infa rct size was determined by computed tomography . Multiple logistic and linear regression outcome analyses included relevant confounders and potential predictors such as age , gender , stroke severity on admission , body temperature , infections , leucocytosis , diabetes , hypertension , atrial fibrillation , ischaemic heart disease , smoking previous stroke , and comorbidity . FINDINGS Mortality was lower and outcome better in patients with mild hypothermia on admission ; both were worse in patients with hyperthermia . Body temperature was independently related to initial stroke severity ( p < 0.009 ) , infa rct size ( p < 0.0001 ) , mortality ( p < 0.02 ) , and outcome in survivors ( SSS at discharge ) ( p < 0.003 ) . For each 1 degrees C increase in body temperature the relative risk of poor outcome ( death or SSS score on discharge < 30 points ) rose by 2.2 ( 95 % CI 1.4 - 3.5 ) ( p < 0.002 ) . INTERPRETATION We have shown that , in acute human stroke , an association exists between body temperature and initial stroke severity , infa rct size , mortality , and outcome . Only intervention trials of hypothermic treatment can prove whether this relation is causal Analysis of early deaths  after stroke is important , since some deaths may be preventable . Previous studies have relied on retrospective and often incomplete clinical data , for comparison with pathological findings . The present study is based on 1073 consecutive stroke patients admitted to an intensive care stroke unit from a well-defined population . There were 212 deaths within the first 30 days , yielding a mortality rate of 20 % . Clinical , radiological , and laboratory data were collected prospect ively according to a st and ardized protocol . Autopsies were performed on 90 of the 212 patients , and CT scanning on a further 27 .  Early mortality after stroke exhibits a bimodal distribution . One peak occurs during the first week , and a second during the second and third weeks . The majority of deaths in the first week are due to transtentorial herniation . Of these , deaths due to hemorrhage usually occur within the first three days , whilst deaths due to infa rct ion peak between the third and sixth day post ictus . After the first week , deaths due to relative immobility ( pneumonia , pulmonary embolism and sepsis ) predominate , peaking towards the end of the second week . Cardiac deaths occur throughout the first month , and unfortunately account for many deaths in patients with small functional deficits . Stroke VOL 15 , No 3 , BACKGROUND AND PURPOSE No neuroradiological markers have been characterized that support a timely decision for decompressive surgery in malignant middle cerebral artery ( MCA ) infa rct ion ( mMCAI ) . This case-control study was design ed to analyze whether early cerebral CT ( CCT ) scanning provides reliable information for the prospect i ve selection of stroke patients at risk of developing mMCAI . METHODS Thirty-one pairs ( n=62 ) were formed with cases ( mMCAI ) and controls ( acute but not malignant MCA infa rct ion ) closely matched in terms of age , sex , and stroke etiology .  CCT was performed within 18 hours of stroke onset and analyzed by a blinded neuroradiologist according to a defined panel of 12 CCT criteria . RESULTS In terms of predicting mMCAI , the criteria of extended MCA territory hypodensities > 67 % and > 50 % , hemispheric brain swelling , midline shift , and hyperdense MCA sign exhibited high specificity ( 100 % , 93 . 5 % , 100 % , 96.7 % , and 83.9 % , respectively ) but low sensitivity ( 45.2 % , 58.1 % , 12.9 % , 19.4 % , and 70.9 % , respectively ) . Two criteria yielded high sensitivity ( subarachnoid space compressed , 100 % ; cella media compressed , 80.6 % ) but low specificity ( 29 % and 74.2 % , respectively ) . The criterion of attenuated corticomedullary contrast yielded both high specificity ( 96.8 % ) and sensitivity ( 87.1 % ) . The latter remained as the crucial criterion [ Exp(B)=90.8 ; 95 % CI , 5.8 to 1427 . 5 ] in a 2-tailed logistic regression analysis with the strongest correlating parameters ( Spearman correlation factor > /=0.6 or < /=-0.6 ) . CONCLUSIONS The analysis of CCT scans within 18 hours of stroke onset revealed an attenuated corticomedullary contrast as the crucial CCT criterion , which , with both sufficient sensitivity and specificity , predicted mMCAI with 95 % certainty Background and Purpose — Cerebral venous pressure is governed by intracranial pressure , cerebral perfusion pressure , and venous outflow resistance . Therefore , changes in venous flow velocities are to be expected because of changes 
    Output:
    
Results : Infa rct size was the major determinant of the development of life-threatening edema .
Other associated determinants were early mass effect , involvement of other vascular territories , higher body temperature , internal carotid artery occlusion , and need for mechanical ventilation .
However , predictive values were only moderate .
Conclusions : The size of the ischemic area is the major determinant .
Single predictors lack sufficient predictive value to select c and i date s for surgical decompression before the onset of clinical signs of herniation