Figure 2. In vivo MR spectrum acquired with a point-resolved spectroscopy (PRESS) sequence with an echo time of 35ms of a bi-thalamic astrocytoma at initial presentation. Citrate (Cit) is detectable at approximately 2.6ppm. Other chemicals that can be observed with in vivo MRS not analyzed for this report) include choline (Cho), creatine (Cr), N-acetyl-aspartate (NAA), myo-inositol (mI), and glycine (Glyc, overlapping with mI). Subsequent to the MR examination a biopsy was performed, and a diffuse astrocytoma (WHO II) was diagnosed. The tumor, however, progressed rapidly within 6 months.