(Downloading may take up to 30 seconds. If the slide opens in your browser, select File -> Save As to save it.)
Terms and Conditions for Use
Click on image to view larger version.
View larger version (153K)
Figure 3a: Measurement of fractional anisotropy values in various tumor and peritumoral regions in 56-year-old woman with biopsy-proved World Health Organization grade IV glioblastoma multiforme. Normalized fractional anisotropy values in solid enhancing tumor are similar to those in adjacent unenhancing regions (which may represent vasogenic edema or unenhancing tumor). (a) Transverse contrast-enhanced T1-weighted image shows enhancing mass in left parietal lobe. Regions of interest (ROIs) have been placed in solid portion of tumor (1), hypointense region (vasogenic edema or unenhancing tumor) adjacent to tumor (3), normal-appearing WM adjacent to region of hypointense signal near tumor (5), and in corresponding contralateral WM areas (2, 4, 6). (b) Transverse echo-planarMR image from diffusion-tensor sequence before application of diffusion gradients (b = 0 sec/mm2) on which ROIs from a have been superimposed confirms that ROI 1 is located in region of hyperintense signal related to enhancing tumor, 3 is in area of peritumoral edema or unenhancing infiltrating tumor, and 5 is in region of normal signal intensity. (c) Color-coded fractional anisotropy map (yellow and red = high anisotropy, blue = low) shows anisotropy values in enhancing tumor that are 42% of those in corresponding contralateral regions.
