ABSTRACT: We explored the relationship between predicted infarct core, predicted ischemic penumbras and predicted final infarct volumes obtained though apparent diffusion coefficient (ADC)-based method, as well as other clinical variables, and functional outcome.
Patients with acute cerebral ischemic stroke were retrospectively recruited. The National Institutes of Health Stroke Scale score was evaluated at baseline and the modified Rankin Scale (mRS) at day 90. Favorable outcome was defined as an mRS score of 0 to 2, and unfavorable outcome as 3 to 6. Multimodal stroke magnetic resonance imaging was carried out at presentation. The volumes of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) were measured using the regions of interest (ROI) method. The volumes of predicted infarct core, predicted ischemic penumbra and predicted final infarct were obtained by an automated image analysis system based on baseline ADC maps. The association between baseline magnetic resonance imaging volumes, baseline clinical variables, and functional outcome was statistically analyzed.
The study included 30 males and 20 females (mean±SD age, 56±10 years). Baseline DWI, PWI and PWI-DWI mismatch volumes were not correlated with day-90 mRS (P>0.05). Predicted infarct core, predicted ischemic penumbra and predicted final infarct through ADC-based method were all correlated with day-90 mRS (P<0.05). A better outcome was associated with a smaller predicted volume. Low baseline National Institutes of Health Stroke Scale and recanalization also demonstrated a trend toward a favorable outcome. Receiver operating characteristic analysis showed that the area under the curve of predicted final infarct volume and recanalization were higher with statistical significance (P<0.001).
Predicted volumes obtained from ADC-based methods, especially predicted final infarct volume, as well as baseline National Institutes of Health Stroke Scale and recanalization may have effect on functional outcome in acute ischemic stroke.
Neurological Research 06/2011; 33(5):494-502. · 1.52 Impact Factor
ABSTRACT: To investigate whether baseline apparent diffusion coefficient (ADC) maps can be employed to predict both infarct core and salvageable ischemic tissue volumes in acute ischemic stroke.
An automated image analysis system based on baseline ADC maps was tested against 30 patients with acute ischemic stroke of anterior circulation to predict both infarct core and salvageable ischemic tissue volumes. The predicted infarct core and predicted salvageable ischemic tissue were quantitatively and qualitatively compared with follow-up imaging data in recanalization and no recanalization groups, respectively. Direct comparisons with perfusion- and diffusion- weighted magnetic resonance imaging measures were also made. Wilcoxon signed-rank test, Spearman rank correlation, and Bland-Altman plots were performed.
In the recanalization group, the predicted infarct core volume was significantly correlated with the final infarct volume (r = 0. 868, P < .001). In the no recanalization group, the predicted final infarct volume (sum of the predicted infarct core and salvageable ischemic tissue volumes), as well as the predicted salvageable ischemic tissue volume, was also significantly correlated with the true final infarct volume (r = 0.955, P < .001) and infarct growth (r = 0.918, P < .001), respectively. The volumes of perfusion-diffusion mismatch were significantly larger than those of infarct growth and predicted salvageable ischemic tissue. Good agreement between predicted and true final infarct lesions was visualized by Bland-Altman plots in two groups. Direct visual comparative analysis revealed good qualitative agreement between the true final infarct and predicted lesions in 21 patients.
The proposed ADC based approach may be a feasible and practical tool to predict the volumes of infarct core and salvageable ischemic tissue without intravenous contrast media-enhanced perfusion-weighted imaging at baseline.
Academic radiology 12/2010; 17(12):1506-17. · 2.09 Impact Factor
ABSTRACT: To investigate the evolution of HCV quasispecies in persistent and self-limited infection patients.
Peripheral blood HCV preserved for 10 years from 8 naive patients were analyzed. HCV core and E2 genes were cloned and sequenced. Genetic distances of different isolates at different time were analyzed by phylip software.
The genetic distances of HCV quasispecies were higher in persistent infection patients than that of self-limited patients. In each patient the genetic distance of HCV E2 region isolates were higher than that of HCV C region which has some relationship between each other. In the 4 persistent patients there exist no differences between within-group and between-group genetic distance in HCV C region and also exist no differences in HCV E2 region in 2 of the 4 persistent patients.
The diversity degree of HCV quasispecies may affect the outcome of hepatitis C. Research on HCV C and E2 region to study HCV quasispecies may obtain different results. The distribution of HCV quasispecies may be stable in hepatitis C natural history.
Zhonghua yi xue za zhi 06/2003; 83(10):841-3.