Hemodynamic mechanisms underlying elevated oxygen extraction fraction (OEF) in moyamoya and sickle cell anemia patients
Year: 2016
Type: article
Study design: Observational Study
Abstract: Moyamoya is a bilateral, complex cerebrovascular condition characterized by progressive non-atherosclerotic intracranial stenosis and collateral vessel formation. Moyamoya treatment focuses on restoring cerebral blood flow (CBF) through surgical revascularization, however stratifying patients for revascularization requires abilities to quantify how well parenchyma is compensating for arterial steno-occlusion. Globally elevated oxygen extraction fraction (OEF) secondary to CBF reduction may serve as a biomarker for tissue health in moyamoya patients, as suggested in patients with sickle cell anemia (SCA) and reduced oxygen carrying capacity. Here, OEF was measured (TRUST-MRI) to test the hypothesis that OEF is globally elevated in patients with moyamoya (n = 18) and SCA (n = 18) relative to age-matched controls (n = 43). Mechanisms underlying the hypothesized OEF increases were evaluated by performing sequential CBF-weighted, cerebrovascular reactivity (CVR)-weighted, and structural MRI. Patients were stratified by treatment and non-parametric tests applied to compare study variables (significance: two-sided P < 0.05). OEF was significantly elevated in moyamoya participants (interquartile range = 0.38-0.45) compared to controls (interquartile range = 0.29-0.38), similar to participants with SCA (interquartile range = 0.37-0.45). CBF was inversely correlated with OEF in moyamoya participants. Elevated OEF was only weakly related to reductions in CVR, consistent with basal CBF level, rather than vascular reserve capacity, being most closely associated with OEF.
Institution: Vanderbilt University Medical Center
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Funders: American Heart Association, Vanderbilt University, National Institutes of Health, National Institute on Aging, National Cancer Institute, National Institute of General Medical Sciences, National Institute of Neurological Disorders and Stroke, National Institute of Biomedical Imaging and Bioengineering, National Center for Research Resources, National Center for Advancing Translational Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development
Awards: G1088833974, High-Performance Computer Cluster for Biomedical Research, G1611882188, Risk factors and prevention targets for abnormal cognitive aging, G2847990249, TSPO-PET to Image Pancreatic Cancer and High-Risk Precursor Lesions, Medical Scientist Training Program, G3884610240, Imaging collaterals and tissue metabolism in patients with Moyamoya syndrome, G4425699080, Eunice Kennedy Shriver Intellectual and Developmental Disabilities Research Center at Vanderbilt University, G5868276417, G6031754694, Institutional Predoctoral Training Program in Biomedical Imaging Science, Characterizing Hemodynamic Compensation and Stroke Risk in Stenosis Patients, The Vanderbilt Institute for Clinical and Translational Research (VICTR), G883715986, Postdoctoral Training in Biomedical MRI and MRS, Vanderbilt Memory & Aging Project
OpenAlex ID: W2562044650