Assessment of tissue viability using diffusion- and perfusion-weighted MRI in hyperacute stroke.

Content Provider	Europe PMC
Author	Moon, Won-Jin Na, Dong Gyu Ryoo, Jae Wook Roh, Hong Gee Byun, Hong Sik Jeon, Yong Hwan Chung, Eun Chul
Copyright Year	2005
Abstract	ObjectiveThe aim of this study was to investigate the relationship between the diffusion and perfusion parameters in hyperacute infarction, and we wanted to determine the viability threshold for the ischemic penumbra using diffusion- and perfusion-weighted imaging (DWI and PWI, respectively).Materials and MethodsBoth DWI and PWI were performed within six hours from the onset of symptoms for 12 patients who had suffered from acute stroke. Three regions of interest (ROIs) were identified: ROI 1 was the initial lesion on DWI; ROI 2 was the DWI/PWI mismatch area (the penumbra) that progressed onward to the infarct; and ROI 3 was the mismatch area that recovered to normal on the follow-up scans. The ratios of apparent diffusion coefficient (ADC), the relative cerebral blood volume (rCBV), and the time to peak (TTP) were calculated as the lesions' ROIs divided by the contralateral mirror ROIs, and these values were then correlated with each other. The viability threshold was determined by using the receiver operating characteristic (ROC) curves.ResultsFor all three ROIs, the ADC ratios had significant linear correlation with the TTP ratios (p < 0.001), but not with the rCBV ratios (p = 0.280). There was no significant difference for the ADC and rCBV ratios within the ROIs. The mean TTP ratio/TTP delay between the penumbras' two ROIs showed a significant statistical difference (p < 0.001). The cutoff value between ROI 2 and ROI 3, as the viability threshold, was a TTP ratio of 1.29 (with a sensitivity and specificity of 86% and 73%, respectively) and a TTP delay of 7.8 sec (with a sensitivity and specificity of 84% and 72%, respectively).ConclusionDetermining the viability thresholds for the TTP ratio/delay on the PWI may be helpful for selecting those patients who would benefit from the various therapeutic interventions that can be used during the acute phase of ischemic stroke.
ISSN	12296929
Journal	Korean Journal of Radiology
Volume Number	6
PubMed Central reference number	PMC2686423
Issue Number	2
PubMed reference number	15968145
e-ISSN	20058330
DOI	10.3348/kjr.2005.6.2.75
Language	English
Publisher	The Korean Radiological Society
Publisher Date	2005-04-01
Access Restriction	Open
Rights License	This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright © 2005 The Korean Radiological Society
Subject Keyword	Brain, diffusion Brain, infarction Brain, MR Brain, perfusion Magnetic resonance (MR), diffusion study Magnetic resonance (MR), perfusion study
Content Type	Text
Resource Type	Article
Subject	Radiology, Nuclear Medicine and Imaging