Acute Stroke Imaging

Feasibility and Value of MR Angiography with High Spatial and Temporal Resolution for Vessel Assessment and Perfusion Analysis in Patients with Wake-up Stroke
Published:January 16, 2015DOI:

      Rationale and Objectives

      Magnetic resonance (MR) imaging (MRI) provides information that can be used to estimate the symptom onset in patients with wake-up stroke (WUS). Time-resolved MR angiography (MRA) is the fastest available MR sequence technique for vessel assessment, and the different phases acquired can provide information about cerebral perfusion. The aim of this study was to evaluate the diagnostic performance of time-resolved MRA both for the assessment of vessel morphology and for the feasibility of perfusion.

      Materials and Methods

      Nineteen patients with WUS were included. Image quality and vessel pathologies were evaluated and correlated to time-of-flight–MRA (n = 14), computed tomography–angiography (n = 4), sonography (n = 12), and conventional angiography (n = 6). The temporal delay of signal enhancement in all pixels of the time-resolved MRA measurement after contrast injection was evaluated and compared to dynamic susceptibility contrast-enhanced (DSC) perfusion imaging (n = 13).


      Time-resolved MRA resulted in the diagnosis of large vessel disease in 14 of 19 patients, involving the internal carotids (n = 4), the vertebral arteries (n = 3), and the circle of Willis (n = 10). All severe vascular pathologies which influence patients' acute stroke therapy were obtained by time-resolved MRA. Overestimation of stenoses in two of 14 patients resulted in sensitivity and specificity of 100% and 71%, respectively. Time-to-peak (TTP) estimations were hampered by movement artifacts in four patients (31%). Compared to DSC, the area of TTP delay was comparable in size and localization without relevant overestimation or underestimation.


      Time-resolved MRA is a valuable technique in patients with WUS with high sensitivity and high negative predictive value. Cerebral perfusion estimation can be performed in selected cases for therapy decision but can be hampered by patient movement.

      Key Words

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        • Latchaw R.E.
        • Alberts M.J.
        • Lev M.H.
        • et al.
        Recommendations for imaging of acute ischemic stroke: a scientific statement from the American Heart Association.
        Stroke. 2009; 40: 3646-3678
        • Roveri L.
        • La Gioia S.
        • Ghidinelli C.
        • et al.
        Wake-up stroke within 3 hours of symptom awareness: imaging and clinical features compared to standard recombinant tissue plasminogen activator treated stroke.
        J Stroke Cerebrovasc Dis. 2013; 22: 703-708
        • Thomalla G.
        • Cheng B.
        • Ebinger M.
        • et al.
        DWI-FLAIR mismatch for the identification of patients with acute ischaemic stroke within 4.5 h of symptom onset (PRE-FLAIR): a multicentre observational study.
        Lancet Neurol. 2011; 10: 978-986
        • Cho A.H.
        • Sohn S.I.
        • Han M.K.
        • et al.
        Safety and efficacy of MRI-based thrombolysis in unclear-onset stroke. A preliminary report.
        Cerebrovasc Dis. 2008; 25: 572-579
        • Castano C.
        • Dorado L.
        • Guerrero C.
        • et al.
        Mechanical thrombectomy with the Solitaire AB device in large artery occlusions of the anterior circulation: a pilot study.
        Stroke. 2010; 41: 1836-1840
        • Gralla J.
        • Brekenfeld C.
        • Mordasini P.
        • et al.
        Mechanical thrombolysis and stenting in acute ischemic stroke.
        Stroke. 2012; 43: 280-285
        • Lim R.P.
        • Shapiro M.
        • Wang E.Y.
        • et al.
        3D time-resolved MR angiography (MRA) of the carotid arteries with time-resolved imaging with stochastic trajectories: comparison with 3D contrast-enhanced Bolus-Chase MRA and 3D time-of-flight MRA.
        AJNR Am J Neuroradiol. 2008; 29: 1847-1854
        • Forkert N.D.
        • Kaesemann P.
        • Treszl A.
        • et al.
        Comparison of 10 TTP and Tmax estimation techniques for MR perfusion-diffusion mismatch quantification in acute stroke.
        AJNR Am J Neuroradiol. 2013; 34: 1697-1703
        • Forkert N.D.
        • Illies T.
        • Moller D.
        • et al.
        Analysis of the influence of 4D MR angiography temporal resolution on time-to-peak estimation error for different cerebral vessel structures.
        AJNR Am J Neuroradiol. 2012; 33: 2103-2109
        • Ma H.
        • Parsons M.W.
        • Christensen S.
        • et al.
        A multicentre, randomized, double-blinded, placebo-controlled Phase III study to investigate EXtending the time for Thrombolysis in Emergency Neurological Deficits (EXTEND).
        Int J Stroke. 2012; 7: 74-80
        • Albers G.W.
        • Thijs V.N.
        • Wechsler L.
        • et al.
        Magnetic resonance imaging profiles predict clinical response to early reperfusion: the diffusion and perfusion imaging evaluation for understanding stroke evolution (DEFUSE) study.
        Ann Neurol. 2006; 60: 508-517
        • Adams Jr., H.P.
        • Bendixen B.H.
        • Kappelle L.J.
        • et al.
        Classification of subtype of acute ischemic stroke. Definitions for use in a multicenter clinical trial. TOAST. Trial of Org 10172 in Acute Stroke Treatment.
        Stroke. 1993; 24: 35-41
        • Serafin Z.
        • Strzesniewski P.
        • Lasek W.
        • et al.
        Time-resolved imaging of contrast kinetics does not improve performance of follow-up MRA of embolized intracranial aneurysms.
        Med Sci Monit. 2012; 18: MT60-MT65
        • Parmar H.
        • Ivancevic M.K.
        • Dudek N.
        • et al.
        Neuroradiologic applications of dynamic MR angiography at 3 T.
        Magn Reson Imaging Clin N Am. 2009; 17: 63-75
        • Parmar H.
        • Ivancevic M.K.
        • Dudek N.
        • et al.
        Dynamic MRA with four-dimensional time-resolved angiography using keyhole at 3 tesla in head and neck vascular lesions.
        J Neuroophthalmol. 2009; 29: 119-127
        • Wu Q.
        • Li M.H.
        A comparison of 4D time-resolved MRA with keyhole and 3D time-of-flight MRA at 3.0 T for the evaluation of cerebral aneurysms.
        BMC Neurol. 2012; 12: 50
        • Lee Y.J.
        • Laub G.
        • Jung S.L.
        • et al.
        Low-dose 3D time-resolved magnetic resonance angiography (MRA) of the supraaortic arteries: correlation with high spatial resolution 3D contrast-enhanced MRA.
        J Magn Reson Imaging. 2011; 33: 71-76
        • Yigit H.
        • Turan A.
        • Ergun E.
        • et al.
        Time-resolved MR angiography of the intracranial venous system: an alternative MR venography technique.
        Eur Radiol. 2012; 22: 980-989
        • Schaafsma J.D.
        • Velthuis B.K.
        • Majoie C.B.
        • et al.
        Intracranial aneurysms treated with coil placement: test characteristics of follow-up MR angiography–multicenter study.
        Radiology. 2010; 256: 209-218
        • Forkert N.D.
        • Fiehler J.
        • Ries T.
        • et al.
        Reference-based linear curve fitting for bolus arrival time estimation in 4D MRA and MR perfusion-weighted image sequences.
        Magn Reson Med. 2011; 65: 289-294
        • Benner T.
        • Heiland S.
        • Erb G.
        • et al.
        Accuracy of gamma-variate fits to concentration–time curves from dynamic susceptibility-contrast enhanced MRI: influence of time resolution, maximal signal drop and signal-to-noise.
        Magn Reson Imaging. 1997; 15: 307-317
        • Lu D.
        • Monahan W.G.
        Effect of sample numbers on the kinetic data analysis of MR contrast agents.
        Magn Reson Med. 1993; 30: 131-134
        • Zou Z.
        • Ma L.
        • Cheng L.
        • et al.
        Time-resolved contrast-enhanced MR angiography of intracranial lesions.
        J Magn Reson Imaging. 2008; 27: 692-699
        • Frolich A.M.
        • Psychogios M.N.
        • Klotz E.
        • et al.
        Angiographic reconstructions from whole-brain perfusion CT for the detection of large vessel occlusion in acute stroke.
        Stroke. 2012; 43: 97-102
        • Dani K.A.
        • Thomas R.G.
        • Chappell F.M.
        • et al.
        Systematic review of perfusion imaging with computed tomography and magnetic resonance in acute ischemic stroke: heterogeneity of acquisition and postprocessing parameters: a translational medicine research collaboration multicentre acute stroke imaging study.
        Stroke. 2012; 43: 563-566
        • Wintermark M.
        • Albers G.W.
        • Alexandrov A.V.
        • et al.
        Acute stroke imaging research roadmap.
        AJNR Am J Neuroradiol. 2008; 29: e23-e30
        • Khan R.
        • Nael K.
        • Erly W.
        Acute stroke imaging: what clinicians need to know.
        Am J Med. 2013; 126: 379-386
        • Aoki J.
        • Kimura K.
        • Iguchi Y.
        • et al.
        FLAIR can estimate the onset time in acute ischemic stroke patients.
        J Neurol Sci. 2010; 293: 39-44
        • Petkova M.
        • Rodrigo S.
        • Lamy C.
        • et al.
        MR imaging helps predict time from symptom onset in patients with acute stroke: implications for patients with unknown onset time.
        Radiology. 2010; 257: 782-792
        • Emeriau S.
        • Serre I.
        • Toubas O.
        • et al.
        Can diffusion-weighted imaging-fluid-attenuated inversion recovery mismatch (positive diffusion-weighted imaging/negative fluid-attenuated inversion recovery) at 3 Tesla identify patients with stroke at <4.5 hours?.
        Stroke. 2013; 44: 1647-1651
        • Serena J.
        • Davalos A.
        • Segura T.
        • et al.
        Stroke on awakening: looking for a more rational management.
        Cerebrovasc Dis. 2003; 16: 128-133
        • Neumann-Haefelin T.
        • Wittsack H.J.
        • Wenserski F.
        • et al.
        Diffusion- and perfusion-weighted MRI. The DWI/PWI mismatch region in acute stroke.
        Stroke. 1999; 30: 1591-1597
        • Prosser J.
        • Butcher K.
        • Allport L.
        • et al.
        Clinical-diffusion mismatch predicts the putative penumbra with high specificity.
        Stroke. 2005; 36: 1700-1704