Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-25T07:33:56.522Z Has data issue: false hasContentIssue false

Acute Stroke Imaging Part I: Fundamentals

Published online by Cambridge University Press:  02 December 2014

K. Butcher*
Affiliation:
Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
D. Emery
Affiliation:
Department of Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada
*
Division of Neurology, 2E3 WMC Health Sciences Centre, University of Alberta, 8440 112th St., Edmonton, Alberta, T6G 2B7, Canada.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Neuroimaging is essential to stroke diagnosis and management. To date, the non-contrast CT has served as our main diagnostic tool. Although brain parenchymal changes visible on CT do provide valuable prognostic information, they provide limited insight into the potential for tissue salvage in response to reperfusion therapy, such as thrombolysis. Newer advanced CT and MRI based imaging techniques have increased the detection sensitivity for hyperacute and chronic parenchymal changes, including ischemia and hemorrhage, permit visualization of blood vessels and cerebral blood flow. This review outlines the basic principles underlying acquisition and interpretation of these newer imaging modalities in the setting of acute stroke. The utility of advanced brain parenchymal and blood flow imaging in the context of acute stroke patient management is also discussed. Part II in this series is a discussion of how these techniques can be used to rationally select appropriate patients for thrombolysis based on pathophysiological data.

Résumé:

RÉSUMÉ:

La neuroimagerie est essentielle au diagnostic et à la prise en charge de l’accident vasculaire cérébral. À ce jour, la tomodensitométrie sans contraste constitue le principal outil diagnostique. Bien que les changements du parenchyme cérébral visibles à la tomodensitométrie fournissent une information précieuse sur le pronostic, ils offrent peu d’informations sur la possibilité de préserver des tissus potentiellement viables en réponse aux traitements de reperfusion comme la thrombolyse. L’imagerie basée sur les techniques nouvelles plus avancées de tomodensitométrie et de résonance magnétique ont augmenté la sensibilité de détection des changements parenchymateux hyperaigus et chroniques, dont l’ischémie et l’hémorragie, et permettent la visualisation des vaisseaux sanguins et du flot sanguin cérébral. Cette revue décrit les principes de base sous–jacents à l’acquisition et à l’interprétation de ces nouvelles modalités d’imagerie dans le contexte de l’accident vasculaire cérébral aigu. L’utilité de l’imagerie spécialisée du parenchyme et du flot sanguin cérébral dans le contexte de la prise en charge de l’accident vasculaire cérébral est également abordée. La deuxième partie de cette série discute de l’utilisation de ces techniques pour sélectionner de façon appropriée les patients pour la thrombolyse en se basant sur des données physiopathologiques.

Type
Review Article
Copyright
Copyright © The Canadian Journal of Neurological 2010

References

1. Astrup, J, Siesjo, BK, Symon, L. Thresholds in cerebral ischemia - the ischemic penumbra. Stroke. 1981 Nov-Dec;12(6):7235.Google Scholar
2. Hacke, W, Donnan, G, Fieschi, C, Kaste, M, von Kummer, R, Broderick, JP, et al. Association of outcome with early stroke treatment: pooled analysis of ATLANTIS, ECASS, and NINDS rt-PA stroke trials. Lancet. 2004 Mar 6;363(9411):76874.Google ScholarPubMed
3. Tissue plasminogen activator for acute ischemic stroke. The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group. N Engl J Med. 1995 Dec 14;333(24): 15817.Google Scholar
4. Hacke, W, Kaste, M, Bluhmki, E, Brozman, M, Davalos, A, Guidetti, D, et al. Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke. N Engl J Med. 2008 Sep 25;359(13):131729.Google Scholar
5. Butcher, KS, Lee, SB, Parsons, MW, Allport, L, Fink, J, Tress, B, et al. Differential prognosis of isolated cortical swelling and hypoattenuation on CT in acute stroke. Stroke. 2007 Mar;38(3): 9417.Google Scholar
6. Na, DG, Kim, EY, Ryoo, JW, Lee, KH, Roh, HG, Kim, SS, et al. CT sign of brain swelling without concomitant parenchymal hypoattenuation: comparison with diffusion- and perfusion-weighted MR imaging. Radiology. 2005 Jun;235(3):99248.Google Scholar
7. Dzialowski, I, Weber, J, Doerfler, A, Forsting, M, von Kummer, R. Brain tissue water uptake after middle cerebral artery occlusion assessed with CT. J Neuroimaging. 2004 Jan;14(1):428.CrossRefGoogle ScholarPubMed
8. Kucinski, T, Majumder, A, Knab, R, Naumann, D, Fiehler, J, Vaterlein, O, et al. Cerebral perfusion impairment correlates with the decrease of CT density in acute ischaemic stroke. Neuroradiology. 2004 Sep;46(9):71622.CrossRefGoogle ScholarPubMed
9. von Kummer, R, Bourquain, H, Bastianello, S, Bozzao, L, Manelfe, C, Meier, D, et al. Early prediction of irreversible brain damage after ischemic stroke at CT. Radiology. 2001 Apr;219(1):95100.Google Scholar
10. von Kummer, R. Early major ischemic changes on computed tomography should preclude use of tissue plasminogen activator. Stroke. 2003 Mar;34(3):8201.CrossRefGoogle ScholarPubMed
11. von Kummer, R, Allen, KL, Holle, R, Bozzao, L, Bastianello, S, Manelfe, C, et al. Acute stroke: usefulness of early CT findings before thrombolytic therapy. Radiology. 1997 Nov;205(2): 32733.CrossRefGoogle ScholarPubMed
12. Butcher, K, Parsons, M, Baird, T, Barber, A, Donnan, G, Desmond, P, et al. Perfusion thresholds in acute stroke thrombolysis. Stroke. 2003;34:215964.Google Scholar
13. Furlan, M, Marchal, G, Viader, F, Derlon, JM, Baron, JC. Spontaneous neurological recovery after stroke and the fate of the ischemic penumbra. Ann Neurol. 1996 Aug;40(2):21626.CrossRefGoogle ScholarPubMed
14. Parsons, MW, Pepper, EM, Bateman, GA, Wang, Y, Levi, CR. Identification of the penumbra and infarct core on hyperacute noncontrast and perfusion CT. Neurology. 2007 Mar 6;68(10): 7306.Google Scholar
15. Pexman, JH, Barber, PA, Hill, MD, Sevick, RJ, Demchuk, AM, Hudon, ME, et al. Use of the Alberta Stroke Program Early CT Score (ASPECTS) for assessing CT scans in patients with acute stroke. AJNR Am J Neuroradiol. 2001 Sep;22(8):153442.Google Scholar
16. Barber, PA, Demchuk, AM, Zhang, J, Buchan, AM. Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. Lancet. 2000 May 13;355(9216):16704.Google Scholar
17. Hill, MD, Rowley, HA, Adler, F, Eliasziw, M, Furlan, A, Higashida, RT, et al. Selection of acute ischemic stroke patients for intra-arterial thrombolysis with pro-urokinase by using ASPECTS. Stroke. 2003 Aug;34(8):192531.CrossRefGoogle ScholarPubMed
18. Dzialowski, I, Hill, MD, Coutts, SB, Demchuk, AM, Kent, DM, Wunderlich, O, et al. Extent of early ischemic changes on computed tomography (CT) before thrombolysis: prognostic value of the Alberta Stroke Program Early CT Score in ECASS II. Stroke. 2006 Apr;37(4):9738.Google Scholar
19. Atlas, SW. Magnetic resonance imaging of the brain and spine. 3rd ed. Philadelphia: Lippincott Williams & Wilkins; 2002.Google Scholar
20. Hashemi, RH, Bradley, WG, Lisanti, CJ. MRI: the basics. 2nd ed. Philadelphia: Lippincott Williams & Wilkins; 2004.Google Scholar
21. Hjort, N, Christensen, S, Solling, C, Ashkanian, M, Wu, O, Rohl, L, et al. Ischemic injury detected by diffusion imaging 11 minutes after stroke. Ann Neurol. 2005 Sep;58(3):4625.Google Scholar
22. Saur, D, Kucinski, T, Grzyska, U, Eckert, B, Eggers, C, Niesen, W, et al. Sensitivity and interrater agreement of CT and diffusion-weighted MR imaging in hyperacute stroke. AJNR Am J Neuroradiol. 2003 May;24(5):87885.Google Scholar
23. Barber, PA, Darby, DG, Desmond, PM, Gerraty, RP, Yang, Q, Li, T, et al. Identification of major ischemic change. Diffusion-weighted imaging versus computed tomography. Stroke. 1999;30(10): 205965.Google Scholar
24. Okamoto, K, Ito, J, Ishikawa, K, Sakai, K, Tokiguchi, S. Diffusion-weighted echo-planar MR imaging in differential diagnosis of brain tumors and tumor-like conditions. Eur Radiol. 2000;10(8): 134250.Google Scholar
25. Reddy, JS, Mishra, AM, Behari, S, Husain, M, Gupta, V, Rastogi, M, et al. The role of diffusion-weighted imaging in the differential diagnosis of intracranial cystic mass lesions: a report of 147 lesions. Surg Neurol. 2006 Sep;66(3):24650; discussion 50-1.Google Scholar
26. Kuker, W, Ruff, J, Gaertner, S, Mehnert, F, Mader, I, Nagele, T. Modern MRI tools for the characterization of acute demyelinating lesions: value of chemical shift and diffusion-weighted imaging. Neuroradiology. 2004 Jun;46(6):4216.Google Scholar
27. Kono, K, Inoue, Y, Nakayama, K, Shakudo, M, Morino, M, Ohata, K, et al. The role of diffusion-weighted imaging in patients with brain tumors. AJNR Am J Neuroradiol. 2001 Jun-Jul;22(6): 10818.Google Scholar
28. Desmond, PM, Lovell, AC, Rawlinson, AA, Parsons, MW, Barber, PA, Yang, Q, et al. The value of apparent diffusion coefficient maps in early cerebral ischemia. AJNR Am J Neuroradiol. 2001 Aug;22(7):12607.Google Scholar
29. Ulug, AM, Beauchamp, N, Bryan, RN, van Zijl, PC. Absolute quantitation of diffusion constants in human stroke. Stroke. 1997;28:48390.CrossRefGoogle ScholarPubMed
30. Kidwell, CS, Saver, JL, Mattiello, J, Starkman, S, Vinuela, F, Duckwiler, G, et al. Thrombolytic reversal of acute human cerebral ischemic injury shown by diffusion/perfusion magnetic resonance imaging. Ann Neurol. 2000;47(4):4629.Google Scholar
31. Oppenheim, C, Grandin, C, Samson, Y, Smith, A, Duprez, T, Marsault, C, et al. Is there an apparent diffusion coefficient threshold in predicting tissue viability in hyperacute stroke? Stroke. 2001 Nov;32(11):248691.Google Scholar
32. Loh, PS, Butcher, K, Parsons, M, Desmond, P, Tress, B, Davis, S. ADC thresholds do not predict the response to thrombolysis. Stroke. 2005;Dec;36(12):262631.Google Scholar
33. Hayman, L, Taber, K, Ford, J, Bryan, R. Mechanisms of MR signal alteration by acute intracerebral blood: old concepts and new theories. AJNR Am J Neuroradiol. 1991;12 (5):899907.Google Scholar
34. Zamani, AA. Imaging of intracranial hemorrhage. In: Rumbaugh, CL, Wang, A, Tsai, FY, editors. Cerebrovascular disease imaging and interventional treatment options. New York: Igaku-Shoin; 1995. p. 23247.Google Scholar
35. Linfante, I, Llinas, RH, Caplan, LR, Warach, S. MRI features of intracerebral hemorrhage within 2 hours from symptom onset. Stroke. 1999;30(11):22637.Google Scholar
36. Butcher, KS, Baird, T, MacGregor, L, Desmond, P, Tress, B, Davis, S. Perihematomal edema in primary intracerebral hemorrhage is plasma derived. Stroke. 2004;35(8):187985.Google Scholar
37. Patel, MR, Edelman, RR, Warach, S. Detection of Hyperacute Primary Intraparenchymal Hemorrhage by Magnetic Resonance Imaging. Stroke. 1996;27(12):23214.Google Scholar
38. Lin, DD, Filippi, CG, Steever, AB, Zimmerman, RD. Detection of intracranial hemorrhage: comparison between gradient-echo images and b(0) images obtained from diffusion-weighted echo-planar sequences. AJNR Am J Neuroradiol. 2001 Aug;22(7): 127581.Google Scholar
39. Hardy, PA, Kucharczyk, W, Henkelman, RM. Cause of signal loss in MR images of old hemorrhagic lesions. Radiology. 1990 Feb;174(2):54955.Google Scholar
40. Patel, R, Edelman, R, Warach, S. Detection of hyperacute primary intraparenchymal hemorrhge by magnetic resonance imaging. Stroke. 1996;27:23214.CrossRefGoogle Scholar
41. Kidwell, CS, Chalela, JA, Saver, JL, Starkman, S, Hill, MD, Demchuk, AM, et al. Comparison of MRI and CT for detection of acute intracerebral hemorrhage. JAMA. 2004 Oct;292(15):182330.Google Scholar
42. Greenberg, S, Finklestein, S, Schaefer, P. Petechial hemorrhages accompanying lobar hemorrhage: detection by gradient-echo MRI. Neurology. 1996;46(6):17514.Google Scholar
43. Fazekas, F, Kleinert, R, Roob, G, Kleinert, G, Kapeller, P, Schmidt, R, et al. Histopathologic analysis of foci of signal loss on gradient-echo T2*-weighted MR images in patients with spontaneous intracerebral hemorrhage: evidence of microangiopathy-related microbleeds. AJNR Am J Neuroradiol. 1999;20(4):63742.Google Scholar
44. Roob, G, Lechner, A, Schmidt, R, Flooh, E, Hartung, H-P, Fazekas, F. Frequency and location of microbleeds in patients with primary intracerebral hemorrhage. Stroke. 2000;31 (11):26659.CrossRefGoogle ScholarPubMed
45. Roob, G, Kleinert, R, Seifert, T, Lechner, A, Kapeller, P, Kleinert, G, et al. [Indications of cerebral micro-hemorrhage in MRI. Comparative histological findings and possible clinical significance]. Nervenarzt. 1999 Dec;70(12):10827.Google Scholar
46. Jeerakathil, T, Wolf, PA, Beiser, A, Hald, JK, Au, R, Kase, CS, et al. Cerebral microbleeds: prevalence and associations with cardiovascular risk factors in the Framingham Study. Stroke. 2004 Aug;35(8):18315.Google Scholar
47. Roob, G, Schmidt, R, Kapeller, P, Lechner, A, Hartung, HP, Fazekas, F. MRI evidence of past cerebral microbleeds in a healthy elderly population. Neurology. 1999 Mar 23;52(5):9914.Google Scholar
48. Chalela, JA, Kang, DW, Warach, S. Multiple cerebral microbleeds: MRI marker of a diffuse hemorrhage-prone state. J Neuroimaging. 2004 Jan;14(1):547.Google Scholar
49. Kidwell, CS, Saver, JL, Villablanca, JP, Duckwiler, G, Fredieu, A, Gough, K, et al. Magnetic resonance imaging detection of microbleeds before thrombolysis: an emerging application. Stroke. 2002 Jan;33(1):958.Google Scholar
50. Nighoghossian, N, Hermier, M, Adeleine, P, Blanc-Lasserre, K, Derex, L, Honnorat, J, et al. Old microbleeds are a potential risk factor for cerebral bleeding after ischemic stroke: a gradient-echo T2*-weighted brain MRI study. Stroke. 2002 Mar;33(3):73542.Google Scholar
51. Kakuda, W, Thijs, VN, Lansberg, MG, Bammer, R, Wechsler, L, Kemp, S, et al. Clinical importance of microbleeds in patients receiving IV thrombolysis. Neurology. 2005 Oct 25;65(8):11758.Google Scholar
52. Zimmerman, RA. Recent advances in MR imaging: FLAIR imaging. Crit Rev Neurosurg. 1998 May 13;8(3): 18892.Google Scholar
53. Noguchi, K, Ogawa, T, Seto, H, Inugami, A, Hadeishi, H, Fujita, H, et al. Subacute and chronic subarachnoid hemorrhage: diagnosis with fluid-attenuated inversion-recovery MR imaging. Radiology. 1997 Apr;203(1):25762.Google Scholar
54. Singer, M, Atlas, S, Drayer, B. Subarachnoid space disease: diagnosis with fluid-attenuated inversion- recovery MR imaging and comparison with gadolinium-enhanced spin-echo MR imaging-blinded reader study. Radiology. 1998 August 1, 1998;208(2): 41722.Google Scholar
55. Ohta, T, Kuroiwa, T. Timing of CT scanning after SAH. J Neurosurg. 1985 Nov;63(5):817.Google Scholar
56. van Gijn, J, van Dongen, KJ. The time course of aneurysmal haemorrhage on computed tomograms. Neuroradiology. 1982; 23(3):1536.Google Scholar
57. Imaizumi, T, Chiba, M, Honma, T, Niwa, J. Detection of hemosiderin deposition by T2*-weighted MRI after subarachnoid hemorrhage. Stroke. 2003 Jul;34(7):16938.Google Scholar
58. Stoner, T, Braff, S, Khoshyomn, S. High signal in subarachnoid spaces on FLAIR MR images in an adult with propofol sedation. Neurology. 2002 Jul 23;59(2):292.Google Scholar
59. Frigon, C, Jardine, DS, Weinberger, E, Heckbert, SR, Shaw, DW. Fraction of inspired oxygen in relation to cerebrospinal fluid hyperintensity on FLAIR MR imaging of the brain in children and young adults undergoing anesthesia. AJR Am J Roentgenol. 2002 Sep;179(3):7916.Google Scholar
60. Manawadu, D, Butcher, K. Evolving hyperdense middle cerebral artery sign. J Neurol Neurosurg Psychiatry. 2008 Oct;79 (10):1106.Google Scholar
61. Yu, D, Schaefer, PW, Rordorf, G, Gonzalez, RG. Magnetic resonance angiography in acute stroke. Semin Roentgenol. 2002 Jul;37(3): 2128.Google Scholar
62. Sohn, CH, Sevick, RJ, Frayne, R. Contrast-enhanced MR angiography of the intracranial circulation. Magn Reson Imaging Clin N Am. 2003 Nov;11(4):599614.Google Scholar
63. Marchal, G, Michiels, J, Bosmans, H, Van Hecke, P. Contrast-enhanced MRA of the brain. J Comput Assist Tomogr. 1992 Jan-Feb;16(1):259.Google Scholar
64. Debrey, SM, Yu, H, Lynch, JK, Lovblad, KO, Wright, VL, Janket, SJ, et al. Diagnostic accuracy of magnetic resonance angiography for internal carotid artery disease: a systematic review and meta-analysis. Stroke. 2008 Aug;39(8):223748.Google Scholar
65. Pomerantz, SR, Harris, GJ, Desai, HJ, Lev, MH. Computed tomography angiography and computed tomography perfusion in ischemic stroke: a step-by-step approach to image acquisition and three-dimensional postprocessing. Semin Ultrasound CT MR. 2006 Jun;27(3):24370.Google Scholar
66. Lev, MH, Farkas, J, Rodriguez, VR, Schwamm, LH, Hunter, GJ, Putman, CM, et al. CT angiography in the rapid triage of patients with hyperacute stroke to intraarterial thrombolysis: accuracy in the detection of large vessel thrombus. J Comput Assist Tomogr. 2001 Jul-Aug;25(4):5208.Google Scholar
67. Nguyen-Huynh, MN, Wintermark, M, English, J, Lam, J, Vittinghoff, E, Smith, WS, et al. How accurate is CT angiography in evaluating intracranial atherosclerotic disease? Stroke. 2008 Apr;39(4):11848.Google Scholar
68. Yeung, R, Ahmad, T, Aviv, RI, de Tilly, LN, Fox, AJ, Symons, SP. Comparison of CTA to DSA in determining the etiology of spontaneous ICH. Can J Neurol Sci. 2009 Mar;36(2):17680.Google Scholar
69. Thompson, AL, Kosior, JC, Gladstone, DJ, Hopyan, JJ, Symons, SP, Romero, F, et al. Defining the CT angiography ‘spot sign’ in primary intracerebral hemorrhage. Can J Neurol Sci. 2009 Jul;36(4):45661.Google Scholar
70. Mnyusiwalla, A, Aviv, RI, Symons, SP. Radiation dose from multidetector row CT imaging for acute stroke. Neuroradiology. 2009 Jun 9. [Epub ahead of print]Google Scholar
71. Hjort, N, Butcher, K, Davis, S, Kidwell, CS, Koroshetz, WJ, Rother, J, et al. Magnetic resonance imaging criteria for thrombolysis in acute cerebral infarct. Stroke. 2005;36(2):38897.Google Scholar
72. Ostergaard, L, Sorensen, AG, Kwong, KK, Weisskoff, RM, Gyldensted, C, Rosen, BR. High resolution measurement of cerebral blood flow using intravascular tracer bolus passages. Part II: Experimental comparison and preliminary results. Magn Reson Med. 1996;36(5):72636.Google Scholar
73. Ostergaard, L, Weisskoff, RM, Chesler, DA, Gyldensted, C, Rosen, BR. High resolution measurement of cerebral blood flow using intravascular tracer bolus passages. Part I: Mathematical approach and statistical analysis. Magn Reson Med. 1996;36(5):71525.Google Scholar
74. Ostergaard, L, Smith, DF, Vestergaard-Poulsen, P, Hansen, SB, Gee, AD, Gjedde, A, et al. Absolute cerebral blood flow and blood volume measured by magnetic resonance imaging bolus tracking: comparison with positron emission tomography values. J Cereb Blood Flow Metab. 1998 Apr;18(4):42532.Google Scholar
75. Wintermark, M, Maeder, P, Thiran, JP, Schnyder, P, Meuli, R. Quantitative assessment of regional cerebral blood flows by perfusion CT studies at low injection rates: a critical review of the underlying theoretical models. Eur Radiol. 2001;11(7): 122030.Google Scholar
76. Nabavi, DG, Cenic, A, Craen, RA, Gelb, AW, Bennett, JD, Kozak, R, et al. CT assessment of cerebral perfusion: experimental validation and initial clinical experience. Radiology. 1999 Oct;213(1): 1419.Google Scholar
77. Wintermark, M, Thiran, JP, Maeder, P, Schnyder, P, Meuli, R. Simultaneous measurement of regional cerebral blood flow by perfusion CT and stable xenon CT: a validation study. AJNR Am J Neuroradiol. 2001 May;22(5):90514.Google Scholar
78. Kudo, K, Terae, S, Katoh, C, Oka, M, Shiga, T, Tamaki, N, et al. Quantitative cerebral blood flow measurement with dynamic perfusion CT using the vascular-pixel elimination method: comparison with H2(15)O positron emission tomography. AJNR Am J Neuroradiol. 2003 Mar;24(3):41926.Google Scholar