The Usefulness of Diffusion-tensor MR Imaging (DTI) in the Grading of Gliomas

ABSTRACT

PURPOSE: The purpose of this study was to evaluate the usefulness of diffusion tensor imaging (DTI) in the grading of gliomas. MATERIALS AND METHODS: DTI was performed in 24 patients with histologically confirmed brain gliomas. After placing the regions of interest (ROI) in the tumor center, tumor border, white matter adjacent to tumor, and normal-appearing white matter (NAWM) of the contralateral hemisphere, the FA values were measured. The size of the ROI was found to be 61 ml. In addition, the FA ratios were calculated for the ROIs in relation to the NAWM of the contralateral hemisphere. RESULTS: The mean FA ratios in patients with grade II gliomas were 0.348 for the tumor center, 0.564 for the tumor border, and 0.897 for the white matter adjacent to the tumor. For patients with grade III gliomas, the mean FA values were 0.247, 0.346, 0.782, respectively. Further, for patients with grade IV gliomas, the mean FA values were 0.204, 0.226, 0.336, respectively. The differences in the FA ratios between the grade II and III tumors were significant in the tumor center and tumor border (p = 0.005, p = 0.002, respectively). Moreover, the differences in the FA ratios between the grade III and IV tumors were significant in the tumor border and white matter adjacent to the tumor (p = 0.004, p = 0.004, respectively). CONCLUSION: DTI is a non-invasive imaging modality that may provide valuable information for the pre-operative grading of gliomas.