Published Online:Apr 1 2001https://doi.org/10.1148/radiology.219.1.r01ap0695
Abstract
PURPOSE: To assess the capability of computed tomography (CT) in the prediction of irreversible ischemic brain damage and its association with the clinical course within 6 hours of stroke onset.
MATERIALS AND METHODS: Serial CT scans obtained within 6 hours of stroke onset, at 22–96 hours (median, 1 day), and at 2–36 days (median, 7 days) after symptom onset in 786 patients with ischemic stroke were prospectively studied, and follow-up CT scans were used as the reference. Clinical variables were assessed prospectively and independently of CT evaluation.
RESULTS: The specificity and positive predictive value of ischemic edema at baseline CT for brain infarcts were 85% (95% CI: 77%, 91%) and 96% (95% CI: 94%, 98%), respectively. Sensitivity and negative predictive values were 64% (95% CI: 60%, 67%) and 27% (95% CI: 23%, 32%), respectively. Patients without early CT findings were less severely affected (P < .001), developed smaller infarcts (P < .001), had fewer intracranial bleeding events (P < .001), and had a better clinical outcome at 90 days (P < .001) compared with patients with hypoattenuating brain tissue at early CT.
CONCLUSION: After ischemic stroke, x-ray hypoattenuation at CT is highly specific for irreversible ischemic brain damage if detection occurs within the first 6 hours. Patients without hypoattenuating brain tissue have a more favorable clinical course.
References
- 1 Astrup J, Siesjo B, Symon L. Thresholds in cerebral ischemia: the ischemic penumbra. Stroke 1981; 12:723-725. Crossref, Medline, Google Scholar
- 2 Heiss W, Rosner G. Functional recovery of cortical neurons as related to degree and duration of ischemia. Ann Neurol 1983; 14:294-301. Crossref, Medline, Google Scholar
- 3 Hossmann KA. Viability thresholds and the penumbra of focal ischemia. Ann Neurol 1994; 36:557-565. Crossref, Medline, Google Scholar
- 4 Jones T, Morawetz R, Crowell R, et al. Thresholds of focal cerebral ischemia in awake monkeys. J Neurosurg 1981; 54:773-782. Crossref, Medline, Google Scholar
- 5 Garcia J, Liu KF, Ho KL. Neuronal necrosis after middle cerebral artery occlusion in Wistar rats progresses at different time intervals in the caudoputamen and the cortex. Stroke 1995; 26:636-643. Crossref, Medline, Google Scholar
- 6 Watanabe O, West CR, Bremer A. Experimental regional cerebral ischemia in the middle cerebral artery territory in primates. II. Effects on brain water and electrolytes in the early phase of MCA stroke. Stroke 1977; 8:71-76. Crossref, Medline, Google Scholar
- 7 Schuir FJ, Hossmann KA. Experimental brain infarcts in cats. II. Ischemic brain edema. Stroke 1980; 11:593-601. Crossref, Medline, Google Scholar
- 8 Mintorovitch J, Yang G, Shimizu H, Kucharczyk J, Chan P, Weinstein P. Diffusion-weighted magnetic resonance imaging of acute focal cerebral ischemia: comparison of signal intensity with changes in brain water and Na+,K+ -ATPase activity. J Cereb Blood Flow Metab 1994; 14:332-336. Crossref, Medline, Google Scholar
- 9 Ianotti F, Hoff J. Ischemic brain edema with and without reperfusion: an experimental study in gerbils. Stroke 1983; 14:562-567. Crossref, Medline, Google Scholar
- 10 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, Medline, Google Scholar
- 11 von Kummer R. Effect of training in reading CT scans on patient selection for ECASS II. Neurology 1998; 51(suppl 3):S50-S52. Crossref, Medline, Google Scholar
- 12 Berry C. A tutorial on confidence intervals for proportions in diagnostic radiology. AJR Am J Roentgenol 1990; 154:477-480. Crossref, Medline, Google Scholar
- 13 Bozzao L, Bastianello S, Fantozzi LM, Angeloni U, Argentino C, Fieschi C. Correlation of angiographic and sequential CT findings in patients with evolving cerebral infarction. AJNR Am J Neuroradiol 1989; 10:1215-1222. Medline, Google Scholar
- 14 Becker H, Desche H, Hacker H, Pencz A. CT fogging effect with ischemic cerebral infarcts. Neuroradiology 1979; 18:185- 192. Crossref, Medline, Google Scholar
- 15 Skriver E, Olsen T. Transient disappearance of cerebral infarcts on CT scan, the so-called fogging effect. Neuroradiology 1981; 22:61-65. Crossref, Medline, Google Scholar
- 16 Skriver EB, Olsen TS. Contrast enhancement of cerebral infarcts: incidence and clinical value in different states of cerebral infarction. Neuroradiology 1982; 23:259-265. Crossref, Medline, Google Scholar
- 17 Tomura N, Uemura K, Inugami A, Fujita H, Higano S, Shishido F. Early CT finding in cerebral infarction. Radiology 1988; 168:463-467. Link, Google Scholar
- 18 Horowitz SH, Zito JL, Donnarumma R, Patel M, Alvir J. Computed tomographic-angiographic findings within the first five hours of cerebral infarction. Stroke 1991; 22:1245-1253. Crossref, Medline, Google Scholar
- 19 Garcia J. Morphology of global cerebral ischemia: a review. Crit Care Med 1988; 16:979-987. Crossref, Medline, Google Scholar
- 20 Unger E, Littlefield J, Gado M. Water content and water structure in CT and MR signal changes: possible influence in detection of early stroke. AJNR Am J Neuroradiol 1988; 9:687-691. Medline, Google Scholar
- 21 von Kummer R, Weber J. Brain and vascular imaging in acute ischemic stroke: the potential of computed tomography. Neurology 1997; 49:S52-S55. Crossref, Medline, Google Scholar
- 22 Truwit C, Barkovich A, Gean-Marton A, Hibri N, Norman D. Loss of the insular ribbon: another early CT sign of acute middle cerebral artery infarction. Radiology 1990; 176:801-806. Link, Google Scholar
- 23 von Kummer R, Holle R, Grzyska U, et al. Interobserver agreement in assessing early CT signs of middle cerebral artery infarction. AJNR Am J Neuroradiol 1996; 17:1743-1748. Medline, Google Scholar
- 24 Marks M, Holmgren E, Fox A, Patel S, von Kummer R, Froehlich J. Evaluation of early computed tomographic findings in acute ischemic stroke. Stroke 1999; 30:389-392. Crossref, Medline, Google Scholar
- 25 von Kummer R, Meyding-Lamade U, Forsting M, et al. Sensitivity and prognostic value of early computed tomography in middle cerebral artery trunk occlusion. AJNR Am J Neuroradiol 1994; 15:9-15. Medline, Google Scholar
- 26 Hacke W, Kaste M, Fieschi C, et al. Intravenous thrombolysis with recombinant tissue plasminogen activator for acute hemispheric stroke: the European Cooperative Acute Stroke Study (ECASS). JAMA 1995; 274:1017-1025. Crossref, Medline, Google Scholar
- 27 Moulin T, Cattin F, Crepin-Leblond T, et al. Early CT signs in acute middle cerebral artery infarction: predictive value for subsequent infarct locations and outcome. Neurology 1996; 47:355-375. Google Scholar
- 28 Castillo M. Prethrombolysis brain imaging: trends and controversies. AJNR Am J Neuroradiol 1997; 18:1830-1834. Medline, Google Scholar
- 29 Gilman S. Imaging of the brain. N Engl J Med 1998; 338:812-820. Crossref, Medline, Google Scholar
- 30 Beauchamp N, Barker P, Wang P, van Zijo P. Imaging of acute cerebral ischemia. Radiology 1999; 212:307-324. Link, Google Scholar
- 31 Kidwell C, Alger J, Di Salle F, et al. Diffusion MRI in patients with transient ischemic attacks. Stroke 1999; 30:1174-1180. Crossref, Medline, Google Scholar
- 32 Lecouvet F, Duprez T, Raymackers J, Peeters A, Cosnard G. Resolution of early diffusion-weighted and FLAIR MRI abnormalities in a patient with TIA. Neurology 1999; 52:1085-1087. Crossref, Medline, Google Scholar
- 33 von Kummer R, Allen K, Holle R, et al. Acute stroke: usefulness of early CT findings before thrombolytic therapy. Radiology 1997; 205:327-333. Link, Google Scholar
- 34 Skriver E, Olsen T. Repeated computed tomography in lacunar infarcts of the brain. Acta Radiol 1989; 30:1-6. Crossref, Medline, Google Scholar
- 35 Pantano P, Caramia F, Bozzao L, Dieler C, von Kummer R. Delayed increase in infarct volume after cerebral ischemia: correlations with thrombolytic treatment and clinical outcome. Stroke 1999; 30:502-507. Crossref, Medline, Google Scholar
