Fig 3. ROC curves representing discriminatory capability of perfusion MR imaging, ¹H-MRSI and combination of ¹H-MRSI and perfusion MR imaging to differentiate between tumors and nonneoplastic lesions. We constructed the curves using data on 30 subjects evaluated with both perfusion MR imaging and MRSI. The calculated areas under the ROC curves were 0.92 for MRSI, 0.89 for perfusion MR imaging, and 0.96 for the analysis on the basis of MRSI and perfusion MR imaging. We found no significant differences when comparing the areas under the curves, indicating that each procedure had similar discriminatory capability for these subjects.