Rachel Scheidegger1, 2, Eric T. Wong3, 4, David C. Alsop1, 5
1Radiology, Beth Israel Deaconess Medical Center, Boston, MA, United States; 2Health Sciences and Technology, Harvard-MIT, Cambridge, MA, United States; 3Brain Tumor Center & Neuro-Oncology Unit, Beth Israel Deaconess Medical Center, Boston, MA, United States; 4Neurology, Harvard Medical School, Boston, MA, United States; 5Radiology, Harvard Medical School, Boston, MA, United States
We report a study targeted at separating the different saturation transfer signals from amide, amine, aliphatic protons and macromolecular magnetization transfer contrast (MTC) and identifying their relative contributions to CEST contrast in high grade glioma patients. Amide exchange could be detected with lower saturation power than has previously been reported in glioma but showed no detectable contrast in tumors. At high saturation powers, amine proton exchange was a major contributor to the observed signal but also showed no contrast in tumors. The loss of broad macromolecular MTC from normal brain tissue was responsible for the majority of contrast with glioma.