Hyperacute Ischemic Stroke: Middle Cerebral Artery Susceptibility Sign at Echo-planar Gradient-Echo MR Imaging

PURPOSE: To evaluate the accuracy of echo-planar T2*-weighted magnetic resonance (MR) sequences in detection of acute middle cerebral artery (MCA) or internal carotid artery (ICA) thrombotic occlusion.

MATERIALS AND METHODS: Forty-two consecutive patients with stroke involving the MCA territory underwent MR imaging within 6 hours after clinical onset. MR examination included echo-planar T2*-weighted, diffusion-weighted (DW), and perfusion-weighted (PW) imaging and MR angiography. Presence or absence of the susceptibility sign on echo-planar T2*-weighted images, which is indicative of acute thrombotic occlusion involving MCA or ICA, was assessed in consensus by two observers blinded to clinical information and other MR imaging data. Differences in lesion volume on DW and PW images between patients with and those without the susceptibility sign were evaluated with the Mann-Whitney test. P < .05 was considered to indicate a significant difference.

RESULTS: Thirty patients (71%) had a positive susceptibility sign that correlated with MCA or ICA occlusion at MR angiography in all cases (sensitivity, 83%; specificity, 100%). Mean lesion volume on PW images was higher in patients with a positive susceptibility sign (P = .01), but no significant differences were found in mean lesion volume on DW images. Cases in which the susceptibility sign was identified proximal to MCA divisional bifurcation (27 patients) showed a mean perfusion deficit of 83.9% of the total MCA territory (range, 50%–100%).

CONCLUSION: Presence of the susceptibility sign proximal to MCA bifurcation provides fast and accurate detection of acute proximal MCA or ICA thrombotic occlusion.

© RSNA, 2004


  • 1 Baird AE, Benfield A, Schlaug G, et al. Enlargement of human cerebral ischemic lesion volumes measured by diffusion-weighted magnetic resonance imaging. Ann Neurol 1997; 41:581-589. Crossref, MedlineGoogle Scholar
  • 2 Baron JC, von Kummer R, del Zoppo GJ. Treatment of acute ischemic stroke: challenging the concept of a rigid and universal time window. Stroke 1995; 26:2219-2221. Crossref, MedlineGoogle Scholar
  • 3 Beaulieu C, de Crespigny A, Tong D, et al. Longitudinal MRI study of perfusion and diffusion in stroke: evolution of lesion volume and correlation with clinical outcome. Ann Neurol 1999; 46:568-578. Crossref, MedlineGoogle Scholar
  • 4 Koroshetz WJ, Gonzalez G. Diffusion-weighted magnetic resonance imaging: an ECG for “brain attack”? Ann Neurol 1997; 41:565-566. Crossref, MedlineGoogle Scholar
  • 5 Minematsu K, Hasegawa Y, Yamaguchi T. Diffusion MRI for evaluating cerebrovascular disease. Rinsho Shinkeigaku 1995; 35:1575-1577. MedlineGoogle Scholar
  • 6 Mohr JP, Biller J, Hilal SK, et al. Magnetic resonance versus computed tomographic imaging in acute stroke. Stroke 1995; 26:807-812. Crossref, MedlineGoogle Scholar
  • 7 Atlas SW, Thulborn KR. MR detection of hyperacute parenchymal hemorrhage of the brain. AJNR Am J Neuroradiol 1998; 19:1471-1477. MedlineGoogle Scholar
  • 8 Patel MR, Edelman RR, Warach S. Detection of hyperacute primary intraparenchymal hemorrhage by magnetic resonance imaging. Stroke 1996; 27:2321-2324. Crossref, MedlineGoogle Scholar
  • 9 Linfante I, Llinas RH, Caplan LR, Warach S. MRI features of intracerebral hemorrhage within 2 hours from symptom onset. Stroke 1999; 30:2263-2267. Crossref, MedlineGoogle Scholar
  • 10 Adams HP, Adams RJ, Brott T, et al. Guidelines for the early management of patients with ischemic stroke. Stroke 2003; 34:1056-1083. Crossref, MedlineGoogle Scholar
  • 11 Moseley ME, Kucharczyk J, Mintorovitch J, et al. Diffusion-weighted MR imaging of acute stroke: correlation with T2-weighted and magnetic susceptibility-enhanced MR imaging in cats. AJNR Am J Neuroradiol 1990; 11:423-429. MedlineGoogle Scholar
  • 12 Mintorovitch J, Moseley ME, Chileuitt L, et al. Comparison of diffusion- and T2-weighted MRI for the early detection of cerebral ischemia and reperfusion in rats. Magn Reson Med 1991; 18:39-50. Crossref, MedlineGoogle Scholar
  • 13 Warach S, Chien D, Li W, Ronthal M, Edelman RR. Fast magnetic resonance diffusion-weighted imaging of acute human stroke. Neurology 1992; 42:1717-1723. Crossref, MedlineGoogle Scholar
  • 14 Fisher M, Albers GW. Applications of diffusion-perfusion magnetic resonance imaging in acute ischemic stroke. Neurology 1999; 52:1750-1756. Crossref, MedlineGoogle Scholar
  • 15 Sorensen AG, Buonanno FS, Gonzalez RG, et al. Hyperacute stroke: evaluation with combined multisection diffusion-weighted and hemodynamically weighted echo-planar MR imaging. Radiology 1996; 199:391-401. LinkGoogle Scholar
  • 16 Gonzalez RG, Schaefer PW, Buonanno FS, et al. Diffusion-weighted MR imaging: diagnostic accuracy in patients imaged within 6 hours of stroke symptom onset. Radiology 1999; 210:155-162. LinkGoogle Scholar
  • 17 Jansen O, Schellinger PD, Fiebach JB, Hacke W, Sartor K. Early recanalization in acute ischemic stroke saves tissue at risk defined by MRI. Lancet 1999; 353:2036-2037. Crossref, MedlineGoogle Scholar
  • 18 Marks MP, Tong D, Beaulieu C, et al. Evaluation of early reperfusion and IV rt-PA therapy using diffusion- and perfusion-weighted MRI. Neurology 1999; 52:1792-1798. Crossref, MedlineGoogle Scholar
  • 19 Hacke W, Kaste M, Fieschi C, et al. Randomised double-blind placebo-controlled trial of thrombolytic therapy with intravenous alteplase in acute ischaemic stroke (ECASS II). Lancet 1998; 352:1245-1251. Crossref, MedlineGoogle Scholar
  • 20 Flacke S, Urbach H, Keller E, et al. Middle cerebral artery (MCA) susceptibility sign at susceptibility-based perfusion MR imaging: clinical importance and comparison with hyperdense MCA sign at CT. Radiology 2000; 215:476-482. LinkGoogle Scholar
  • 21 Davis WL, Jacobs J. Normal vascular anatomy. In: Osborn AG, eds. Diagnostic neuroradiology. St Louis, Mo: Mosby-Year Book, 1994; 117-153. Google Scholar
  • 22 Clark RA, Watanabe AT, Bradley WG, Jr, Roberts JD. Acute hematomas: effects of deoxygenation, hematocrit, and fibrin-clot formation and retraction on T2 shortening. Radiology 1990; 175:201-206. LinkGoogle Scholar
  • 23 Atlas SW, Mark AS, Grossman RI, Gomori JM. Intracranial hemorrhage: gradient-echo MR imaging at 1.5T—comparison with spin-echo imaging and clinical applications. Radiology 1988; 168:803-807. LinkGoogle Scholar
  • 24 Hayman LA, Ford JJ, Taber KH, Saleem A, Round ME, Bryan RN. T2 effect of hemoglobin concentration: assessment with in vitro MR spectroscopy. Radiology 1988; 168:489-491. LinkGoogle Scholar
  • 25 Hayman LA, Taber KH, Ford JJ, et al. Effect of clot formation and retraction on spin-echo MR images of blood: an in vitro study. AJNR Am J Neuroradiol 1989; 10:1155-1158. MedlineGoogle Scholar
  • 26 Tomsick T, Brott T, Olinger C, et al. Hyperdense middle cerebral artery sign: incidence and quantitative significance. Neuroradiology 1989; 31:312-315. Crossref, MedlineGoogle Scholar
  • 27 Tomsick T, Brott T, Barsan W, et al. Prognostic value of the hyperdense middle cerebral artery sign on CT: efficacy in detecting middle cerebral artery thrombosis. AJNR Am J Neuroradiol 1990; 11:473-477. MedlineGoogle Scholar
  • 28 Zorzon M, Mase G, Pozzi-Mucelli F, et al. Increased density in the middle cerebral artery by nonenhanced computed tomography: prognostic value in acute cerebral infarction. Eur Neurol 1993; 33:256-259. Crossref, MedlineGoogle Scholar
  • 29 Launes J, Ketonen L. Dense middle cerebral artery sign: an indicator of poor outcome in middle cerebral artery area infarction. J Neurol Neurosurg Psychiatry 1987; 50:1550-1552. Crossref, MedlineGoogle Scholar
  • 30 Tomsick T, Brott T, Barsan W, et al. Prognostic value of the hyperdense middle cerebral artery sign and stroke scale score before ultra early thrombolytic therapy. AJNR Am J Neuroradiol 1996; 17:79-85. MedlineGoogle Scholar
  • 31 Schellinger PD, Fiebach JB, Hacke W. Imaging-based decision making in thrombolytic therapy for ischemic stroke: present status. Stroke 2003; 34:575-583. Crossref, MedlineGoogle Scholar
  • 32 Marler J, Tilley BC, Lu M, et al. Early stroke treatment associated with better outcome: the NINDS rt-PA stroke study. Neurology 2000; 55:1649-1655. Crossref, MedlineGoogle Scholar
  • 33 Tomsick TA. Tick tock, doc: the rapid evaluation of acute stroke to direct therapy and improve patient outcome. AJNR Am J Neuroradiol (editorial) 2000; 21:1177-1179. Google Scholar
  • 34 Hirai T, Korogi Y, Ono K, et al. Prospective evaluation of suspected stenoocclusive disease of the intracranial artery: combined MR angiography and CT angiography compared with digital subtraction angiography. AJNR Am J Neuroradiol 2002; 23:93-101. MedlineGoogle Scholar

Article History

Published in print: Aug 2004