Management of Patients with Ischemic Stroke

In a case with embolic occlusion of cerebral artery, residual cerebral blood flow (CBF) in symptomatic ischemic region is distributed heterogeneously and cerebral infarction is developed gradually from ischemic core to penumbra. Ischemic core is defined as a region with irreversible tissue damage due to fairly poor collateral circulation, and ischemic penumbra is defined as a region with preservation of tissue reversibility in a certain time. Reversibility of ischemic penumbra is also depending on both residual CBF and time from stroke onset, and the existence of ischemic penumbra is essential for thrombolytic therapy. Ischemic penumbra is thought to be the first therapeutic target in management of patients with acute cerebral ischemia. Using 133Xe SPECT imaging, penumbral flow is estimated as 15-30 m1/100g/min within 3 hours from stroke onset and 20-30 m1/100g/min during 3-6 hours from stroke onset. Ischemic penumbra could be diagnosed accurately by both negative findings on DWI and critical flow level in brain perfusion SPECT or other perfusion image. Hemodynamic cerebral ischemia could be stratified into Stage I and Stage II (Misery perfusion). According to vasodilatory and metabolic compensation toward reduction of cerebral perfusion pressure, Stage I ischemia is defined as both preservation of resting CBF and reduction of vascular reserve (VR). Stage II ischemia is defined as reduction of resting CBF associated with loss of VR. The vasodilatory response to acetazolamide provides an effective parameter of VR: (acetazolamide-activated CBF / resting CBF ? 1) X 100%. Stage II ischemia is quantitatively defined as both CBF less than 80% of normal mean CBF and VR less than 10%. Stratification of hemodynamic cerebral ischemia could be important to determine future risk of stroke. Stage II ischemia is thought to be the second therapeutic target in management of patients with hemodynamic cerebral ischemia. The characteristics and kinetics of brain perfusion radiotracers should be considered in quantitative stratification of hemodynamic cerebral ischemia using brain perfusion SPECT

Surgical Treatment of Tentorial Meningiomas ? Based on Our Classification Related to Venous Sinuses ?

We report our experience and long-term results in the surgical treatment of 27 tentorial meningiomas (TMs). These cases were operated on between 1980 to 2000.5 and represented 9.8% of all 275 surgically treated intracranial meningiomas in that period. Of the total 29 TMs (additional 2 non-surgically treated TMs), 25 were women and 4 were men ranging in age from 26 to 75 years (mean 55.2 years). According to the site of tumor attachment and the venous sinuses, these 29 TMs were divided into 6 subgroups: central (C; 3), anterolateral (AL; 3), posterolateral (PL; 6), free edge (FE; 6), anteromedial (AM; 3), and posteromedial (PM; 8). Various surgical approaches were selected on the tumor location and extension, however, these are divided into 2 approaches. One is anterior or posterior petrosal approach, selected in AL and FE cases and the other is combined occipital-suboccipital approach, selected in C, PL, AM, and PM cases. In 17 patients, total removal (Simpson Grade 1 : 8, II : 9) was achieved, subtotal removal (SG III) in 4, and partial removal (SG IV) in 6. Four patients had surgical complications. Gamma knife radiosurgery was performed in 4 residual and 3 recurrent meningiomas. In all these 7 meningiomas, tumor sizes have been well controlled. With a mean follow-up of 70 months (2 to 157 months), recurrences occurred in 5 patients (21.7%), which were subtotal and partial removal cases. Glasgow Outcome Scale scores were GR in 21 patients (77.8%), MD in 3 (11.1%), VS in 1 (3.7%), and D in 2 (7.4%)

Acute Cerebral Revascularization : Correlation among Preoperative CBF, Collateral Flow and Surgical Outcome

Twenty-two,patients,of,acute,cerebral,revascularization,were,analyzed,in,order,to,evaluate,various,predictors related to surgical effectiveness and outcome. These patients presented sudden neurological symptoms following occlusion of the middle cerebral artery (MCA). The left MCA was involved in 8 patients, and the right in 14 patients. Prior to surgical intervention, CT scan, serial angiography, and measurement of cerebral blood flow (CBF) were performed. STA-MCA anastomosis was completed in 21 patients, and left MCA embolectomy was performed on one patient. In the 14 patients of the effective group, the time elapsed from onset of stroke to revascularization was an average of 19.5 hours (6-72 hours). Of these patients,7 cases has a residual CBF of 24.8±1.2m1/100g/min (45% of normal CBF). Collateral flow, as judged from the preoperative angiograms, was good in 4 cases, and fair in 10 cases. In the 8 cases of the non-effective group, the time elapsed prior to the restoration of flow was an average of 8.2 hours (6-16 hours). Three cases had a residual CBF of 19.5 ±1.1m//100g/min. Collateral flow was fair in 5 cases, and poor in 3 cases. These results suggest that good preoperative collateral flow and residual CBF constitute the most accurate favorable predictors for the estimation of surgical effectiveness and outcome, and the time limits for acute cerebral revascularization is variable according to the degree of residual CBF supplied by collateral flow patterns

Factors influencing the Effectiveness of Hemodilution Therapy for Patients with Ruptured Cerebral Aneurysm

We operated on 621 patients with subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysm from 1979 to 1987. All the patients were operated on within 72 hours after the rupture of aneurysm. From 1979 to 1983, 312 patients with ruptured intracranial aneurysm were treated without postoperative hemodilution therapy (No-Hemodilution). From 1984 to 1987, 309 patients were treated with hemodilution therapy (Hemodilution). We have performed the hemodilution therapy for the prevention of cerebral ischemia due to vasospasm following SAH since January, 1984. Indication for the hemodilution therapy was the hematocrit value of above 30.0-33.0 % at Day 7 after onset. In the No-Hemodilution period (1979-1983), the mean value of hematocrit of 253 patients was 36.7 % and in the Hemodilution period (1984-1987) , the value of 150 patients was 31.9 %. The difference in these values is statistically significant. From the viewpoint of over-all outcome, the rate of Good Recovery was higher and that of Death was lower in the Hemodilution period (p < 0.001). 1. The correlation of the age and outcome: The mortality was higher with increasing age especially in patients over 60 years (p < 0.001). This result seemed to be due to the vulnerability of the brain by cerebral ischemia in the old age. 2. The correlation of the sites of ruptured aneurysm and outcome: In the ruptured aneurysm of the anterior cerebral artery, the mortality was higher than that of other sites (p < 0.001). Generally, the symptoms of ischemia in the anterior cerebral artery terri tory are more severe than those of other sites. By the hemodilution therapy the symptoms of ische mia in the anterior cerbral artery territory seemed to be prevented. 3. The correlation of the preoperative grade and outcome: The mortality and morbidity were higher especially in the preoperative grade (p < 0.001). In the preoperative grade Id the outcome has a tendency to be determined by the severity of cerebral vasospasm. By the hemodilution therapy the occurrence of ischemia is decreased. We conclude that the hemodilution therapy is effective for the prevention and treatment of cerebral ischemia due to vasognasm

System evaluation of automated production and inhalation of O-15-labeled gaseous radiopharmaceuticals for the rapid O-15-oxygen PET examinations

Background(15)O-oxygen inhalation PET is unique in its ability to provide fundamental information regarding cerebral hemodynamics and energy metabolism in man. However, the use of O-15-oxygen has been limited in a clinical environment largely attributed to logistical complexity, in relation to a long study period, and the need to produce and inhale three sets of radiopharmaceuticals. Despite the recent works that enabled shortening of the PET examination period, radiopharmaceutical production has still been a limiting factor. This study was aimed to evaluate a recently developed radiosynthesis/inhalation system that automatically supplies a series of O-15-labeled gaseous radiopharmaceuticals of (CO)-O-15, O-15(2), and (CO2)-O-15 at short intervals.MethodsThe system consists of a radiosynthesizer which produces (CO)-O-15, O-15(2), and (CO2)-O-15; an inhalation controller; and an inhalation/scavenging unit. All three parts are controlled by a common sequencer, enabling automated production and inhalation at intervals less than 4.5min. The gas inhalation/scavenging unit controls to sequentially supply of qualified radiopharmaceuticals at given radioactivity for given periods at given intervals. The unit also scavenges effectively the non-inhaled radioactive gases. Performance and reproducibility are evaluated.ResultsUsing an O-15-dedicated cyclotron with deuteron of 3.5MeV at 40A, (CO)-O-15, O-15(2), and (CO2)-O-15 were sequentially produced at a constant rate of 1400, 2400, and 2000MBq/min, respectively. Each of radiopharmaceuticals were stably inhaled at </p

Effects of Comprehensive Stroke Care Capabilities on In-Hospital Mortality of Patients with Ischemic and Hemorrhagic Stroke: J-ASPECT Study

Background: The effectiveness of comprehensive stroke center (CSC) capabilities on stroke mortality remains uncertain. We performed a nationwide study to examine whether CSC capabilities influenced in-hospital mortality of patients with ischemic and hemorrhagic stroke. Methods and Results: Of the 1,369 certified training institutions in Japan, 749 hospitals responded to a questionnaire survey regarding CSC capabilities that queried the availability of personnel, diagnostic techniques, specific expertise, infrastructure, and educational components recommended for CSCs. Among the institutions that responded, data on patients hospitalized for stroke between April 1, 2010 and March 31, 2011 were obtained from the Japanese Diagnosis Procedure Combination database. In-hospital mortality was analyzed using hierarchical logistic regression analysis adjusted for age, sex, level of consciousness on admission, comorbidities, and the number of fulfilled CSC items in each component and in total. Data from 265 institutions and 53,170 emergency-hospitalized patients were analyzed. Mortality rates were 7.8% for patients with ischemic stroke, 16.8% for patients with intracerebral hemorrhage (ICH), and 28.1% for patients with subarachnoid hemorrhage (SAH). Mortality adjusted for age, sex, and level of consciousness was significantly correlated with personnel, infrastructural, educational, and total CSC scores in patients with ischemic stroke. Mortality was significantly correlated with diagnostic, educational, and total CSC scores in patients with ICH and with specific expertise, infrastructural, educational, and total CSC scores in patients with SAH. Conclusions: CSC capabilities were associated with reduced in-hospital mortality rates, and relevant aspects of care were found to be dependent on stroke type

Consciousness Level and Off‐Hour Admission Affect Discharge Outcome of Acute Stroke Patients: A J‐ASPECT Study

Background-Poor outcomes have been reported for stroke patients admitted outside of regular working hours. However, few studies have adjusted for case severity. In this nationwide assessment, we examined relationships between hospital admission time and disabilities at discharge while considering case severity. Methods and Results-We analyzed 35 685 acute stroke patients admitted to 262 hospitals between April 2010 and May 2011 for ischemic stroke (IS), intracerebral hemorrhage (ICH), or subarachnoid hemorrhage (SAH). The proportion of disabilities/death at discharge as measured by the modified Rankin Scale (mRS) was quantified. We constructed 2 hierarchical logistic regression models to estimate the effect of admission time, one adjusted for age, sex, comorbidities, and number of beds; and the second adjusted for the effect of consciousness levels and the above variables at admission. The percentage of severe disabilities/death at discharge increased for patients admitted outside of regular hours (22.8%, 27.2%, and 28.2% for working-hour, off-hour, and nighttime; P<0.001). These tendencies were significant in the bivariate and multivariable models without adjusting for consciousness level. However, the effects of off-hour or nighttime admissions were negated when adjusted for consciousness levels at admission (adjusted OR, 1.00 and 0.99; 95% CI, 1.00 to 1.13 and 0.89 to 1.10; P=0.067 and 0.851 for off-hour and nighttime, respectively, versus working-hour). The same trend was observed when each stroke subtype was stratified. Conclusions-The well-known off-hour effect might be attributed to the severely ill patient population. Thus, sustained stroke care that is sufficient to treat severely ill patients during off-hours is important

Management of Patients with Ischemic Stroke

In a case with embolic occlusion of cerebral artery, residual cerebral blood flow (CBF) in symptomatic ischemic region is distributed heterogeneously and cerebral infarction is developed gradually from ischemic core to penumbra. Ischemic core is defined as a region with irreversible tissue damage due to fairly poor collateral circulation, and ischemic penumbra is defined as a region with preservation of tissue reversibility in a certain time. Reversibility of ischemic penumbra is also depending on both residual CBF and time from stroke onset, and the existence of ischemic penumbra is essential for thrombolytic therapy. Ischemic penumbra is thought to be the first therapeutic target in management of patients with acute cerebral ischemia. Using 133Xe SPECT imaging, penumbral flow is estimated as 15-30 m1/100g/min within 3 hours from stroke onset and 20-30 m1/100g/min during 3-6 hours from stroke onset. Ischemic penumbra could be diagnosed accurately by both negative findings on DWI and critical flow level in brain perfusion SPECT or other perfusion image. Hemodynamic cerebral ischemia could be stratified into Stage I and Stage II (Misery perfusion). According to vasodilatory and metabolic compensation toward reduction of cerebral perfusion pressure, Stage I ischemia is defined as both preservation of resting CBF and reduction of vascular reserve (VR). Stage II ischemia is defined as reduction of resting CBF associated with loss of VR. The vasodilatory response to acetazolamide provides an effective parameter of VR: (acetazolamide-activated CBF / resting CBF － 1) X 100%. Stage II ischemia is quantitatively defined as both CBF less than 80% of normal mean CBF and VR less than 10%. Stratification of hemodynamic cerebral ischemia could be important to determine future risk of stroke. Stage II ischemia is thought to be the second therapeutic target in management of patients with hemodynamic cerebral ischemia. The characteristics and kinetics of brain perfusion radiotracers should be considered in quantitative stratification of hemodynamic cerebral ischemia using brain perfusion SPECT