Abstract
PURPOSE: To investigate additional information provided by maps of relative cerebral blood flow in functional magnetic resonance (MR) imaging of human hyperacute cerebral ischemic stroke.
MATERIALS AND METHODS: Diffusion-weighted and hemodynamic MR imaging were performed in 23 patients less than 12 hours after the onset of symptoms. Maps of relative cerebral blood flow and tracer mean tissue transit time were computed, as were maps of apparent diffusion and relative cerebral blood volume. Acute lesion volumes on the maps were compared with follow-up imaging findings.
RESULTS: In 15 of 23 subjects (65%), blood flow maps revealed hemodynamic abnormalities not visible on blood volume maps. A mismatch between initial blood flow and diffusion findings predicted growth of infarct more often (12 of 15 subjects with infarcts that grew) than did a mismatch between initial blood volume and diffusion findings (eight of 15). However, lesion volumes on blood volume and diffusion maps correlated better with eventual infarct volumes (r > 0.90) than did those on blood flow and tracer mean transit time maps (r ∼ 0.6), likely as a result of threshold effects. In eight patients, blood volume was elevated around the diffusion abnormality, suggesting a compensatory hemodynamic response.
CONCLUSION: MR imaging can delineate areas of altered blood flow, blood volume, and water mobility in hyperacute human stroke. Predictive models of tissue outcome may benefit by including computation of both relative cerebral blood flow and blood volume.
References
- 1 Anonymous . Thrombolytic therapy with streptokinase in acute ischemic stroke: the multicenter acute stroke trial—Europe study group. N Engl J Med 1996; 335:145-150. Crossref, Medline, Google Scholar
- 2 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. JAMA 1995; 274:1017-1025. Crossref, Medline, Google Scholar
- 3 von Kummer R, Allen KL, Holle R, et al. Acute stroke: usefulness of early CT findings before thrombolytic therapy. Radiology 1997; 205:327-333. Link, Google Scholar
- 4 Marchal G, Beaudouin V, Rioux P, et al. Prolonged persistence of substantial volumes of potentially viable brain tissue after stroke: a correlative PET-CT study with voxel-based data analysis. Stroke 1996; 27:599-606. Crossref, Medline, Google Scholar
- 5 Furlan M, Marchal M, Viader F, Derlon JM, Baron JC. Spontaneous neurological recovery after stroke and the fate of the ischemic penumbra. Ann Neurol 1996; 40:216-226. Crossref, Medline, Google Scholar
- 6 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, Medline, Google Scholar
- 7 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. Link, Google Scholar
- 8 Rosen BR, Belliveau JW, Aronen HJ, et al. Susceptibility contrast imaging of cerebral blood volume: human experience. Magn Reson Med 1991; 22:293-299. Crossref, Medline, Google Scholar
- 9 Rosen B, Belliveau J, Buchbinder B, et al. Contrast agents and cerebral hemodynamics. Magn Reson Med 1991; 19:285-292. Crossref, Medline, Google Scholar
- 10 Rosen B, Belliveau J, Vevea J, Brady T. Perfusion imaging with NMR contrast agents. Magn Reson Med 1990; 14:249-266. Crossref, Medline, Google Scholar
- 11 Rosen BR, Aronen HJ, Kwong KK, Belliveau JW, Hamberg LM, Fordham JA. Advances in clinical neuroimaging: functional MR imaging techniques. RadioGraphics 1993; 13:889-896. Link, Google Scholar
- 12 Østergaard L, Weisskoff R, Chesler D, Gyldensted C, Rosen B. High resolution measurement of cerebral blood flow using intravascular tracer bolus passages. I. Mathematical approach and statistical analysis. Magn Reson Med 1996; 36:715-725. Google Scholar
- 13 Østergaard L, Sorensen A, Kwong K, Weisskoff R, Gyldensted C, Rosen B. High resolution measurement of cerebral blood flow using intravascular tracer bolus passages. II. Experimental comparison and preliminary results. Magn Reson Med 1996; 36:726-736. Google Scholar
- 14 Aronen H, Gazit I, Louis D, et al. Cerebral blood volume maps of gliomas: comparison with tumor grade and histologic findings. Radiology 1994; 191:41-51. Link, Google Scholar
- 15 Boxerman J, Weisskoff R, Aronen H, Rosen B. Signal-to-noise and tissue blood volume maps from dynamic NMR imaging studies (abstr) In: Book of abstracts: Society of Magnetic Resonance in Medicine 1992. Berkeley, Calif: Society of Magnetic Resonance in Medicine, 1992; 1130. Google Scholar
- 16 Weisskoff R, Boxerman J, Sorensen A, Kulke S, Campbell T, Rosen B. Simultaneous blood volume and permeability mapping using a single Gd-based contrast injection (abstr) In: Proceedings of the Second Meeting of the Society of Magnetic Resonance. Berkeley, Calif: Society of Magnetic Resonance, 1994; 279. Google Scholar
- 17 Breiman R, Beck J, Korobkin M, et al. Volume determinations using computed tomography. AJR 1982; 138:329-333. Crossref, Medline, Google Scholar
- 18 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, Medline, Google Scholar
- 19 Moseley ME, Mintorovitch J, Cohen Y, et al. Early detection of ischemic injury: comparison of spectroscopy, diffusion-, T2-, and magnetic susceptibility–weighted MRI in cats. Acta Neurochir Suppl (Wien) 1990; 51(suppl):207-209. Medline, Google Scholar
- 20 Welch K, Windham J, Knight R, et al. A model to predict the histopathology of human stroke using diffusion and T2-weighted magnetic resonance imaging. Stroke 1995; 26:1983-1989. Crossref, Medline, Google Scholar
- 21 Lovblad KO, Baird AE, Schlaug G, et al. Ischemic lesion volumes in acute stroke by diffusion-weighted magnetic resonance imaging correlate with clinical outcome. Ann Neurol 1997; 42:164-170. Crossref, Medline, Google Scholar
- 22 Rordorf G, Koroshetz W, Copen W, et al. Regional ischemia and ischemic injury in patients with acute middle cerebral artery stroke as defined by early diffusion-weighted and perfusion-weighted MRI. Stroke 1998; 29:939-943. Crossref, Medline, Google Scholar
- 23 Weisskoff R, Chesler D, Boxerman J, Rosen B. Pitfalls in MR measurement of tissue blood flow with intravascular tracers: which mean transit time?. Magn Reson Med 1993; 29:553-558. Crossref, Medline, Google Scholar
Article History
Accepted: Sept 28 1998Received: Mar 26 1998
Revision received: June 19 1998
Revision received: July 15 1998
Published in print: Feb 1999







