J Nucl Med 2001 Aug;42(8):1195-1197 |
Comparison of PET oxygen extraction fraction methods for the prediction
of stroke risk.
Derdeyn CP, Videen TO, Grubb RL Jr, Powers WJ.
PET measurement of increased oxygen extraction fraction (OEF) identifies patients at high
risk for subsequent stroke. OEF methodology remains controversial. In this study we
compare the sensitivity and specificity of absolute OEF measurements with
ipsilateral-to-contralateral ratios of absolute OEF and count-based OEF estimates.
METHODS: Multivariate analyses of OEF methods were performed using data from patients with
symptomatic carotid artery occlusion (n = 68). Outcome and receiver operating
characteristic (ROC) curve analyses were performed. RESULTS: All 3 methods were predictive
of stroke risk in univariate analysis. Only the count-based method remained significant in
multivariate analysis. The area under the ROC curve was greatest for the count-based
ratio: 0.815 versus 0.769 (absolute) and 0.737 (ratios of absolute). CONCLUSION: All 3
methods are predictive of stroke risk in patients with unilateral carotid artery
occlusion. ROC curve analysis is useful for selecting optimal thresholds for maximal
sensitivity and specificity.