title: Determination of oxygen extraction fraction using magnetic resonance imaging in canine models with internal carotid artery occlusion.
abstract: Perfusion of the penumbra tissue below the flow threshold for functional disturbance but above that for the maintenance of morphological integrity is the target for therapy in acute ischaemic stroke. The measurement of the oxygen extraction fraction (OEF) may provide a direct assessment of tissue viability, so that irreversible tissue damage and penumbra can be reliably identified. By using an asymmetric spin echo single-shot echo planar imaging (ASE-SSEPI) sequence, the quantitative OEF was obtained in the ischaemic brain tissues of canine models with internal carotid artery occlusion. TTC staining, which delineated the regions of infarct and penumbra, was used for defining the corresponding regions on OEF maps. The threshold of the OEF to discriminate the infarct cores and penumbral tissues was then determined according to the OEF values at different times. With repeated-measures ANOVA, the OEF of the infarcted regions was found to be time dependent. An OEF greater than 0.48 best predicted cortical infarction at 1.5 hr, with an area under the receiving operating characteristic curve of 0.968, a sensitivity of 97.5%, and a specificity of 92.5%. Our results may be helpful in the evaluation of tissue viability during stroke events.
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, BeiJing, 100029, China.
authors.forename: Fei-Yan
authors.initials: FY
authors.lastname: Chang
authors.affiliation: Department of Radiology, Peking University First Hospital, BeiJing, 100034, China.
authors.forename: Jiang-Xi
authors.initials: JX
authors.lastname: Xiao
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, BeiJing, 100029, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Xie
authors.affiliation: Department of Radiology, Peking University First Hospital, BeiJing, 100034, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, BeiJing, 100029, China.
authors.forename: Zhen-Xia
authors.initials: ZX
authors.lastname: Zhang
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, BeiJing, 100029, China.
authors.forename: Wu
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Pathology, China-Japan Friendship Hospital, BeiJing, 100029, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Luo
authors.affiliation: GE Healthcare Research, Beijing, 100176, China.
authors.forename: Zhong-Ping
authors.initials: ZP
authors.lastname: Zhang
authors.affiliation: Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University, Beijing, 100084, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Guo
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D018450:Disease Progression; D004285:Dogs; D005260:Female; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000737:chemistry*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D020521:Stroke / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D010100:Oxygen