%0 Journal Article %A P.-F. Tang %A Y.-H. Ko %A Z.-A. Luo %A F.-C. Yeh %A S.-H.A. Chen %A W.-Y.I. Tseng %T Tract-Specific and Region of Interest Analysis of Corticospinal Tract Integrity in Subcortical Ischemic Stroke: Reliability and Correlation with Motor Function of Affected Lower Extremity %D 2010 %R 10.3174/ajnr.A1981 %J American Journal of Neuroradiology %P 1023-1030 %V 31 %N 6 %X BACKGROUND AND PURPOSE: TS analysis has been suggested as a useful method to evaluate the fiber integrity of white matter tracts. This study investigated the intrarater and interrater reliability and validity of a TS analysis for the CST and compared the results with those of a ROI-based analysis. MATERIALS AND METHODS: Diffusion spectrum imaging was performed on 7 patients with subcortical ischemic stroke on a 3T MR imaging system. For the TS analysis, seed regions were placed at the cerebral peduncle and the medial portion of the primary motor cortex to reconstruct the tracts of the CST for motor control of the lower extremity. The mean GFA was measured at the PLIC by calculating the weighted sum of the GFAs sampled by the CST tracts at this segment. For the ROI-based analysis, the posterior two-thirds of the PLIC were enclosed on the GFA maps, and the mean GFA in this ROI was calculated. RESULTS: The results showed good-to-excellent intrarater and interrater reliability on the seed region/ROI placement (mean Îș values >0.80) and mean GFA values (ICCs >0.90) for both the TS and ROI-based analyses. Both the GFAPLIC-TS and GFAPLIC-ROI values were highly correlated with the motor function of the affected lower extremity (r = 0.76 and 0.80, respectively; P < .05). CONCLUSIONS: We demonstrated good reliability and validity of the TS and ROI-based analyses of the CST corresponding to lower extremity motor control in patients with subcortical ischemic stroke. AHaffected hemisphereBGbasal gangliaBOLDblood oxygen level–dependentCPcerebral peduncleCSTcorticospinal tractCVcoefficient of varianceDSIdiffusion spectrum imagingDTIdiffusion tensor imagingFAfractional anisotropyFMA-LEFugl-Meyer assessment of lower extremityGFAgeneralized fractional anisotropyGFAPLIC-TSGFA value of the PLIC calculated by using the tract-specific methodGFAPLIC-ROIGFA value of the PLIC calculated by using the ROI-based methodICCintraclass correlation coefficientsM1primary motor cortex/precentral gyrusMMSEMini-Mental State ExaminationNIHSSNational Institutes of Health Stroke ScalePLICposterior limb of the internal capsuleROIregion of interestSDstandard deviationTStract-specificUHunaffected hemisphere %U https://www.ajnr.org/content/ajnr/31/6/1023.full.pdf