title: Imaging of brain ischemia.
abstract: The extent of the penumbra and the core of an acute ischemic stroke influence, at the given time, the impact of the recanalization of the occluded vessel on the outcome. Research studies have demonstrated that quantitative MR diffusion imaging and, to a lesser extent, CT perfusion (CTP) could provide an acceptable estimation of the size of the core, while perfusion imaging thresholds could outline critically hypoperfused regions. Several software programs now automatically process reliable quantitative diffusion-weighted imaging (DWI) and perfusion maps in real time, making them available for clinical routine. Studies investigating whether acute MRI profile could select patient for acute recanalization after the 4.5h time window approved for rtPA administration are ongoing. Transient ischemic attack (TIA) is a major risk factor for stroke but its clinical diagnosis is difficult. MRI can confirm the ischemic nature of transient neurological symptoms among 50% of the patients and the presence of an acute diffusion lesion is an independent risk factor for acute stroke. Multimodal imaging of ischemic stroke and TIA provides a tissue-based characterization of the ischemic lesion that is dramatically influencing the diagnosis and the management of the patients.
authors: Stanford Stroke Center, Ste 205, 780 Welch Road, Palo Alto 94304, California, USA.
authors: J-M
authors: JM
authors: Olivot
mesh_terms: D002545:Brain Ischemia / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation / Q000502:physiology; D003952:Diagnostic Imaging / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D006801:Humans; D002546:Ischemic Attack, Transient / Q000175:diagnosis / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods; D055420:Perfusion Imaging / Q000379:methods; D011379:Prognosis; D011859:Radiography; D020521:Stroke / Q000175:diagnosis / Q000000981:diagnostic imaging