American Journal of Neuroradiology 25:1205-1210, August 2004
© 2004 American Society of Neuroradiology
BRAIN
CT Perfusion Parameter Values in Regions of Diffusion Abnormalities
a From the Department of Radiology/Neuroradiology, Duke University Medical Center, Durham, NC
Address reprint requests to Gerald E. York, II, MD, Department of Radiology/Neuroradiology, Duke University Medical Center, Box 3808, Durham, NC 27710
BACKGROUND AND PURPOSE: Dynamic CT perfusion imaging is a rapid and widely available method for assessing cerebral hemodynamics in the setting of ischemia. Nevertheless, little is known about perfusion parameters within regions of diffusion abnormality. Since MR diffusion-weighted (DW) imaging is widely considered the most sensitive and specific technique to examine the ischemic core, new knowledge about CT perfusion findings in areas of abnormal diffusion would likely provide valuable information. The purpose of our study was to measure the CT-derived perfusion values within acute ischemic lesions characterized by 1) increased signal intensity on DW images and 2) decreased apparent diffusion coefficient (ADC) and compare these values with those measured in contralateral, normal brain tissue.
METHODS: Analysis was performed in 10 patients with acute middle cerebral artery territory stroke of symptom onset less than 8 hours before imaging who had undergone both CT perfusion and DW imaging within 2 hours. After registration of CT perfusion and DW images, measurements were made on a pixel-by-pixel basis in regions of abnormal hyperintensity on DW images and in areas of decreased ADC.
RESULTS: Significant decreases in cerebral blood flow and cerebral blood volume with elevated mean transit times were observed in regions of infarct as defined by increased signal intensity on DW images and decreased ADC. Comparison of perfusion parameters in regions of core infarct differed significantly from those measured in contralateral normal brain.
CONCLUSION: CT perfusion findings of decreased cerebral blood flow, mean transit time, and cerebrovascular volume correlate with areas of abnormal hyperintensity on DW images and regions of decreased ADC. These findings provide important information about perfusion changes in acute ischemia in areas of diffusion abnormality.
This article has been cited by other articles:
 |
|
 |
|
  A. Srinivasan, M. Goyal, F. A. Azri, and C. Lum State-of-the-Art Imaging of Acute Stroke1 RadioGraphics, October 1, 2006; 26(suppl_1): S75 - S95. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. McKinney, C.L. Truwit, S. Kieffer, P.W. Schaefer, R.G. Gonzalez, M.H. Lev, and W.J. Koroshetz Reversibility of an "Apparent" Infarct on Dynamic Perfusion CT after Lytic Therapy: Comment Regarding Cerebral Blood Flow and Blood Volume Thresholds AJNR Am. J. Neuroradiol., August 1, 2006; 27(7): 1391 - 1393. [Full Text] [PDF]
|
|
|
|
|
|
A.M. Laslo, J.D. Eastwood, F.-X. Chen, and T.-Y. Lee Dynamic CT Perfusion Imaging in Subarachnoid Hemorrhage-Related Vasospasm AJNR Am. J. Neuroradiol., March 1, 2006; 27(3): 624 - 631. [Abstract] [Full Text] [PDF]
|
|