TY - JOUR
T1 - White matter ischemic changes in hyperacute ischemic stroke
T2 - Voxel-based analysis using diffusion tensor imaging and MR perfusion
AU - Nael, Kambiz
AU - Trouard, Theodore P.
AU - Lafleur, Scott R.
AU - Krupinski, Elizabeth A.
AU - Salamon, Noriko
AU - Kidwell, Chelsea S.
N1 - Publisher Copyright:
© 2015 American Heart Association, Inc.
PY - 2015/2/6
Y1 - 2015/2/6
N2 - BACKGROUND AND PURPOSE - : The purpose of this study was to evaluate changes in fractional anisotropy (FA), as measured by diffusion tensor imaging, of white matter (WM) infarction and hypoperfusion in patients with acute ischemic stroke using a quantitative voxel-based analysis. METHODS - : In this prospective study, diffusion tensor imaging and dynamic susceptibility contrast perfusion sequences were acquired in 21 patients with acute ischemic stroke who presented within 6 hours of symptom onset. The coregistered FA, apparent diffusion coefficient, and dynamic susceptibility contrast time to maximum (Tmax) maps were used for voxel-based quantification using a region of interest approach in the ipsilateral affected side and in the homologous contralateral WM. The regions of WM infarction versus hypoperfusion were segmented using a threshold method. Data were analyzed by regression and ANOVA. RESULTS - : There was an overall significant mean difference (P<0.001) for the apparent diffusion coefficient, Tmax, and FA values between the normal, hypoperfused, and infarcted WM. The mean±SD of FA was significantly higher (P<0.001) in hypoperfused WM (0.397±0.019) and lower (P<0.001) in infarcted WM (0.313±0.037) when compared with normal WM (0.360±0.020). Regression tree analysis of hypoperfused WM showed the largest mean FA difference at Tmax above versus below 5.4 s with a mean difference of 0.033 (P=0.0096). CONCLUSIONS - : Diffusion tensor imaging-FA was decreased in regions of WM infarction and increased in hypoperfused WM in patients with hyperacute acute ischemic stroke. The significantly increased FA values in the hypoperfused WM with Tmax≥5.4 s are suggestive of early ischemic microstructural changes.
AB - BACKGROUND AND PURPOSE - : The purpose of this study was to evaluate changes in fractional anisotropy (FA), as measured by diffusion tensor imaging, of white matter (WM) infarction and hypoperfusion in patients with acute ischemic stroke using a quantitative voxel-based analysis. METHODS - : In this prospective study, diffusion tensor imaging and dynamic susceptibility contrast perfusion sequences were acquired in 21 patients with acute ischemic stroke who presented within 6 hours of symptom onset. The coregistered FA, apparent diffusion coefficient, and dynamic susceptibility contrast time to maximum (Tmax) maps were used for voxel-based quantification using a region of interest approach in the ipsilateral affected side and in the homologous contralateral WM. The regions of WM infarction versus hypoperfusion were segmented using a threshold method. Data were analyzed by regression and ANOVA. RESULTS - : There was an overall significant mean difference (P<0.001) for the apparent diffusion coefficient, Tmax, and FA values between the normal, hypoperfused, and infarcted WM. The mean±SD of FA was significantly higher (P<0.001) in hypoperfused WM (0.397±0.019) and lower (P<0.001) in infarcted WM (0.313±0.037) when compared with normal WM (0.360±0.020). Regression tree analysis of hypoperfused WM showed the largest mean FA difference at Tmax above versus below 5.4 s with a mean difference of 0.033 (P=0.0096). CONCLUSIONS - : Diffusion tensor imaging-FA was decreased in regions of WM infarction and increased in hypoperfused WM in patients with hyperacute acute ischemic stroke. The significantly increased FA values in the hypoperfused WM with Tmax≥5.4 s are suggestive of early ischemic microstructural changes.
KW - diffusion imaging
KW - ischemia
KW - magnetic resonance imaging
KW - perfusion imaging
KW - stroke
UR - http://www.scopus.com/inward/record.url?scp=84922274105&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84922274105&partnerID=8YFLogxK
U2 - 10.1161/STROKEAHA.114.007000
DO - 10.1161/STROKEAHA.114.007000
M3 - Article
C2 - 25523053
AN - SCOPUS:84922274105
SN - 0039-2499
VL - 46
SP - 413
EP - 418
JO - Stroke
JF - Stroke
IS - 2
ER -