Fig 1. Transverse T1-weighted (A; TI/TR/TE = 500/9.5/5 ms), ²³Na (B; TR/TE = 25/3.8 ms), and FSE (C; TR/TE = 4500/15 ms) 4T MR images of a typical low-grade glioma in the same patient. The T1-weighted image has a 10-mm section thickness corresponding with the ²³Na image thickness. The white arrow identifies the low-grade glioma in each image. White boxes outline tissue regions in tumor (A) and on the contralateral side (B) studied by spectroscopy.