FIG 2.

TSI findings in a 64-year-old man with a previously treated right parietal glioblastoma multiforme who presented with a rim-enhancing lesion.

A, Three representative spectra are shown from the locations indicated by the yellow stars on the corresponding images.

B and C, The spectroscopic volume is indicated (green line) on a coronal turbo-FLAIR image (B) and in-plane anatomic features are shown on an axial inversion-recovery scan (C).

D–G, Images reconstructed by integrating the area under the Cho (D), Cr (E), NAA (F), and lipid (G) peaks are shown with anatomic overlay contours extracted from the inversion-recovery image. The rim of the lesion exhibits enhanced Cho with corresponding reductions in Cr and NAA as compared with the reference spectrum (A). This is indicative of active tumor growth. The core of this lesion, however, reveals only a pronounced lipid peak, consistent with necrosis