1. A 59-year-old woman with right superior frontal mass initially diagnosed as low-grade astrocytoma.A, Axial postcontrast T1-weighted image shows an ill-defined nonenhancing mass within the right superior frontal lobe.B, Axial FLAIR image demonstrates homogen...
A 59-year-old woman with right superior frontal mass initially diagnosed as low-grade astrocytoma.A, Axial postcontrast T1-weighted image shows an ill-defined nonenhancing mass within the right superior frontal lobe.B, Axial FLAIR image demonstrates homogeneous T2 prolongation within the mass and a single-voxel proton-spectroscopic imaging within the center of the mass reveals a marked increase in lactate (Lac) and choine (Cho) metabolites and a decrease in N-acetylaspartate (NAA) metabolite.C, 3D, lactate-edited, proton spectroscopic image of the same tumor location confirms the presence of lactate metabolite within the tumor. Re-evaluation of the tissue specimen revealed a few mitotic figures and vascular hyperplasia, and the tumor was upgraded to anaplastic astrocytoma.D, Serial axial postcontrast T1-weighted images during 1-year period show emergence of subtle enhancement at the posterior surgical margin at 9-month follow-up (white arrow), which rapidly progresses into an aggressive grade IV astrocytoma (black arrow).
S. Cha AJNR Am J Neuroradiol 2006;27:
©2006 by American Society of Neuroradiology