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PT  - JOURNAL ARTICLE
AU  - Schaefer, P.W.
AU  - Roccatagliata, L.
AU  - Ledezma, C.
AU  - Hoh, B.
AU  - Schwamm, L.H.
AU  - Koroshetz, W.
AU  - Gonzalez, R.G.
AU  - Lev, M.H.
TI  - First-Pass Quantitative CT Perfusion Identifies Thresholds for Salvageable Penumbra in Acute Stroke Patients Treated with Intra-arterial Therapy
DP  - 2006 Jan 01
TA  - American Journal of Neuroradiology
PG  - 20--25
VI  - 27
IP  - 1
4099  - http://www.ajnr.org/content/27/1/20.short
4100  - http://www.ajnr.org/content/27/1/20.full
SO  - Am. J. Neuroradiol.2006 Jan 01; 27
AB  - BACKGROUND AND PURPOSE: The purpose of this study was to determine whether, in acute stroke patients treated with intra-arterial (IA) recanalization therapy, CT perfusion (CTP) can distinguish ischemic brain tissue destined to infarct from that which will survive.METHODS: Dynamic CTP was obtained in 14 patients within 8 hours of stroke onset, before IA therapy. Initial quantitative cerebral blood volume (CBV) and flow (CBF) values were visually segmented and normalized in the “infarct core” (region 1: reduced CBV and CBF, infarction on follow-up), “penumbra that infarcts” (region 2: normal CBV, reduced CBF, infarction on follow-up), and “penumbra that recovers” (region 3: normal CBV, reduced CBF, normal on follow-up). Normalization was accomplished by dividing the ischemic region of interest value by that of a corresponding, contralateral, uninvolved region, which resulted in CBV and CBF “ratios.” Separate CBV and CBF values were obtained in gray matter (GM) and white matter (WM).RESULTS: Mean CBF ratios for regions 1, 2, and 3 were 0.19 ± 0.06, 0.34 ± 0.06, and 0.46 ± 0.09, respectively (all P &amp;lt; .001). Mean CBV ratios for regions 1, 2, and 3 were similarly distinct (all P &amp;lt; .05). Absolute CBV and CBF values for regions 2 and 3 were not significantly different. All regions with CBF ratio &amp;lt;0.32, CBV ratio &amp;lt;0.68, CBF &amp;lt;12.7 mL/100 g/min, or CBV &amp;lt;2.2 mL/100 g infarcted. No region with CBF ratio &amp;gt;0.44 infarcted. GM versus WM CBF and CBV values were significantly different for region 2 compared with region 3 (P &amp;lt; .05).CONCLUSIONS: In acute stroke patients, quantitative CTP can distinguish ischemic tissue likely to infarct from that likely to survive.