TY - JOUR T1 - Oxygen Extraction Fraction and Stroke Risk in Patients with Carotid Stenosis or Occlusion: A Systematic Review and Meta-Analysis JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. DO - 10.3174/ajnr.A3668 AU - A. Gupta AU - H. Baradaran AU - A.D. Schweitzer AU - H. Kamel AU - A. Pandya AU - D. Delgado AU - D. Wright AU - S. Hurtado-Rua AU - Y. Wang AU - P.C. Sanelli Y1 - 2013/08/14 UR - http://www.ajnr.org/content/early/2013/08/14/ajnr.A3668.abstract N2 - BACKGROUND AND PURPOSE: Increased oxygen extraction fraction on PET has been considered a risk factor for stroke in patients with carotid stenosis or occlusion, though the strength of this association has recently been questioned. We performed a systematic review and meta-analysis to summarize the association between increased oxygen extraction fraction and ipsilateral stroke risk. MATERIALS AND METHODS: A comprehensive literature search was performed. We included studies with baseline PET oxygen extraction fraction testing, ipsilateral stroke as the primary outcome, and at least 1 year of follow-up. A meta-analysis was performed by use of a random-effects model. RESULTS: After screening 2158 studies, 7 studies with 430 total patients with mean 30-month follow-up met inclusion criteria. We found that 6 of 7 studies were amenable to meta-analysis. Although 4 of the 6 studies independently did not reach statistical significance, meta-analysis revealed a significant positive relationship between abnormal oxygen extraction fraction and future ipsilateral stroke, with a pooled OR of 6.04 (95% CI, 2.58–14.12). There was no statistically significant difference in OR in the subgroup analyses according to testing method or disease site. CONCLUSIONS: Abnormal oxygen extraction fraction remains a powerful predictor of stroke in carotid stenosis or occlusion and is a valuable reference standard to compare and validate MR imaging–based measures of brain oxygen metabolism. However, there is a need for further evaluation of oxygen extraction fraction testing in patients with high-grade but asymptomatic carotid disease. Abbreviations CVRcerebrovascular reserveOEFoxygen extraction fractionCOSSCarotid Occlusion Surgery Study ER -