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RT Journal Article
SR Electronic
T1 First-Pass Quantitative CT Perfusion Identifies Thresholds for Salvageable Penumbra in Acute Stroke Patients Treated with Intra-arterial Therapy
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 20
OP 25
VO 27
IS 1
A1 Schaefer, P.W.
A1 Roccatagliata, L.
A1 Ledezma, C.
A1 Hoh, B.
A1 Schwamm, L.H.
A1 Koroshetz, W.
A1 Gonzalez, R.G.
A1 Lev, M.H.
YR 2006
UL http://www.ajnr.org/content/27/1/20.abstract
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 &lt; .001). Mean CBV ratios for regions 1, 2, and 3 were similarly distinct (all P &lt; .05). Absolute CBV and CBF values for regions 2 and 3 were not significantly different. All regions with CBF ratio &lt;0.32, CBV ratio &lt;0.68, CBF &lt;12.7 mL/100 g/min, or CBV &lt;2.2 mL/100 g infarcted. No region with CBF ratio &gt;0.44 infarcted. GM versus WM CBF and CBV values were significantly different for region 2 compared with region 3 (P &lt; .05).CONCLUSIONS: In acute stroke patients, quantitative CTP can distinguish ischemic tissue likely to infarct from that likely to survive.