Influence of residual oxygen-15-labeled carbon monoxide radioactivity on cerebral blood flow and oxygen extraction fraction in a dual-tracer autoradiographic method

2009 ◽  
Vol 23 (4) ◽  
pp. 363-371 ◽  
Author(s):  
Katsuhiro Iwanishi ◽  
Hiroshi Watabe ◽  
Takuya Hayashi ◽  
Yoshinori Miyake ◽  
Kotaro Minato ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Oxygen Extraction Fraction ◽  
Oxygen Extraction ◽  
Autoradiographic Method ◽  
Residual Oxygen ◽  
Extraction Fraction ◽  
Dual Tracer

scholarly journals Cerebral Hemodynamics and Executive Function in Sickle Cell Anemia

Stroke ◽  
2021 ◽  
Author(s):  
Kemar V. Prussien ◽  
Bruce E. Compas ◽  
Rachel E. Siciliano ◽  
Abagail E. Ciriegio ◽  
Chelsea A. Lee ◽  
...  
Keyword(s):  
Working Memory ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Executive Function ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Brain Magnetic Resonance Imaging ◽  
Oxygen Extraction Fraction ◽  
Oxygen Extraction ◽  
Extraction Fraction

Background and Purpose: Individuals with sickle cell anemia experience cognitive deficits, even in the absence of cerebral infarcts or strokes. This study tested the hypothesis that elevated cerebral blood flow and oxygen extraction fraction are associated with lower executive function in individuals with sickle cell anemia. Methods: Three-Tesla brain magnetic resonance imaging was performed, including anatomic, gray matter cerebral blood flow, and global oxygen extraction fraction imaging. Executive function was measured using the working memory index from an age-appropriate Wechsler battery and tasks from the National Institutes of Health Toolbox Cognition Battery. Bivariate and multivariate models were examined (significance: P <0.05). Results: Fifty-four participants (age range=6–31 years) with sickle cell anemia were enrolled. Hematocrit was positively related to fluid cognition, cerebral blood flow was inversely related to working memory and inhibitory control, and oxygen extraction fraction was inversely related to processing speed. Associations remained significant in multivariate analyses controlling for age, income, and infarcts. Conclusions: Elevated cerebral blood flow and oxygen extraction fraction, markers of hemodynamic impairment, are associated with deficits in executive function in individuals with sickle cell anemia.

Evaluation of utility of asymmetric index for count-based oxygen extraction fraction on dual-tracer autoradiographic method for chronic unilateral brain infarction

2009 ◽  
Vol 23 (6) ◽  
pp. 533-539
Author(s):  
Katsuhiro Iwanishi ◽  
Hiroshi Watabe ◽  
Hiroshi Fujisaki ◽  
Takuya Hayashi ◽  
Yoshinori Miyake ◽  
...  
Keyword(s):  
Brain Infarction ◽  
Oxygen Extraction Fraction ◽  
Oxygen Extraction ◽  
Autoradiographic Method ◽  
Extraction Fraction ◽  
Unilateral Brain ◽  
Dual Tracer

Reversal of Focal Misery Perfusion after Intracranial Angioplasty: Case Report

Neurosurgery ◽  
2001 ◽  
Vol 48 (2) ◽  
pp. 436-440 ◽  
Author(s):  
Colin P. Derdeyn ◽  
DeWitte T. Cross ◽  
Christopher J. Moran ◽  
Ralph G. Dacey
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Intracranial Stenosis ◽  
Oxygen Extraction Fraction ◽  
Oxygen Extraction ◽  
Positron Emission ◽  
Misery Perfusion ◽  
Before And After ◽  
Hemodynamic Measurements

Abstract OBJECTIVE AND IMPORTANCE The presence of reduced blood flow and increased oxygen extraction fraction (OEF) (misery perfusion) in the hemisphere distal to an occluded carotid artery is a proven risk factor for subsequent stroke. Whether angioplasty of intracranial stenosis is sufficient to reverse this condition has not been documented. CLINICAL PRESENTATION A 67-year-old man exhibited progressive right hemispheric ischemic symptoms despite maximal antiplatelet and antithrombotic therapy. Angiography demonstrated focal 80% stenosis of the supraclinoid segment of the ipsilateral internal carotid artery. TECHNIQUE 15O positron emission tomographic measurements of cerebral blood flow and OEF were made before and after transfemoral percutaneous angioplasty. OEF values measured before angioplasty were elevated in the middle cerebral artery distal to the stenosis. Angioplasty reduced the degree of luminal stenosis to 40% (linear diameter). OEF values measured 36 hours after angioplasty were normal. CONCLUSION Angioplasty of intracranial stenosis can restore normal cerebral blood flow and oxygen extraction, despite mild residual stenosis after the procedure. Hemodynamic measurements may be useful for the identification of patients with the greatest potential to benefit from angioplasty.

Global Oxygen Extraction Fraction by Blood Sampling to Anticipate Cerebral Hyperperfusion Phenomenon After Carotid Artery Stenting

Neurosurgery ◽  
2014 ◽  
Vol 75 (5) ◽  
pp. 546-551 ◽  
Author(s):  
Tomonori Iwata ◽  
Takahisa Mori ◽  
Yuichi Miyazaki ◽  
Yuhei Tanno ◽  
Shigen Kasakura ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Carotid Artery Stenting ◽  
Blood Sampling ◽  
Oxygen Extraction Fraction ◽  
Cerebral Hyperperfusion Syndrome ◽  
Hyperperfusion Syndrome ◽  
Cerebral Hyperperfusion ◽  
Extraction Fraction

Abstract BACKGROUND: Cerebral hyperperfusion syndrome sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent cerebral hyperperfusion syndrome, cerebral hyperperfusion phenomenon (CHP) must be detected early. Single-photon emission computed tomography (SPECT) is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. OBJECTIVE: To investigate whether global oxygen extraction fraction (OEF) by a blood sampling method is useful for indicating CHP after carotid artery stenting (CAS). METHODS: When patients underwent elective CAS from September 2010 to August 2012, we performed blood sampling for OEF calculation and SPECT before and immediately after elective CAS. Data were collected prospectively. OEF was calculated from the cerebral arteriovenous oxygen difference. Cerebral blood flow was measured in the affected middle cerebral artery (MCA) territory and in the ipsilateral cerebellum by SPECT. The ratio of MCA to cerebellar activity was defined as cerebral blood flow in the affected MCA territory divided by cerebral blood flow in the ipsilateral cerebellar hemisphere. Probable CHP was defined as ≥10% increase in the ratio of MCA to cerebellar activity after CAS. The relationship between peri-CAS OEF and probable CHP was evaluated. RESULTS: Of the 96 patients enrolled, 92 patients were analyzed. Probable CHP occurred in 17 patients. Post-CAS OEF was related to probable CHP (P &lt; .01), but pre-CAS OEF was not. The receiver-operating characteristic curve showed that the cutoff value was 45% for probable CHP (P &lt; .001). CONCLUSION: An increase in blood sampling OEF immediately after CAS was related to probable CHP; then the oxygen demand should be reduced.

scholarly journals Effect of ephedrine and phenylephrine on brain oxygenation and microcirculation in anaesthetised patients with cerebral tumours: study protocol for a randomised controlled trial

BMJ Open ◽  
2017 ◽  
Vol 7 (11) ◽  
pp. e018560 ◽  
Author(s):  
Klaus Ulrik Koch ◽  
Anna Tietze ◽  
Joel Aanerud ◽  
Gorm von Öettingen ◽  
Niels Juul ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Metabolic Rate ◽  
Transit Time ◽  
Oxygen Extraction Fraction ◽  
Oxygen Extraction ◽  
Brain Oxygenation ◽  
Cerebral Metabolic Rate ◽  
Arterial Blood ◽  
Extraction Fraction

IntroductionDuring brain tumour surgery, vasopressor drugs are commonly administered to increase mean arterial blood pressure with the aim of maintaining sufficient cerebral perfusion pressure. Studies of the commonly used vasopressors show that brain oxygen saturation is reduced after phenylephrine administration, but unaltered by ephedrine administration. These findings may be explained by different effects of phenylephrine and ephedrine on the cerebral microcirculation, in particular the capillary transit-time heterogeneity, which determines oxygen extraction efficacy. We hypothesised that phenylephrine is associated with an increase in capillary transit-time heterogeneity and a reduction in cerebral metabolic rate of oxygen compared with ephedrine. Using MRI and positron emission tomography (PET) as measurements in anaesthetised patients with brain tumours, this study will examine whether phenylephrine administration elevates capillary transit-time heterogeneity more than ephedrine, thereby reducing brain oxygenation.Methods and analysisThis is a double-blind, randomised clinical trial including 48 patients scheduled for surgical brain tumour removal. Prior to imaging and surgery, anaesthetised patients will be randomised to receive either phenylephrine or ephedrine infusion until mean arterial blood pressure increases to above 60 mm Hg or 20% above baseline. Twenty-four patients were allocated to MRI and another 24 patients to PET examination. MRI measurements include cerebral blood flow, capillary transit-time heterogeneity, cerebral blood volume, blood mean transit time, and calculated oxygen extraction fraction and cerebral metabolic rate of oxygen for negligible tissue oxygen extraction. PET measurements include cerebral metabolic rate of oxygen, cerebral blood flow and oxygen extraction fraction. Surgery is initiated after MRI/PET measurements and subdural intracranial pressure is measured.Ethics and disseminationThis study was approved by the Central Denmark Region Committee on Health Research Ethics (12 June 2015; 1-10-72-116-15). Results will be disseminated via peer-reviewed publication and presentation at international conferences.Trial registration numberNCT02713087; Pre-results. 2015-001359-60; Pre-results.

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