Abstract #2544

Imaging of Endogenous CEST Agents in the Human Brain Using Frequency Labeled Exchange (FLEX) Transfer

Nirbhay N. Yadav¹,², Craig K. Jones¹,², Jun Hua¹,², Jiadi Xu¹,², Peter C.M. van Zijl¹,²

¹Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States; ²FM Kirby Research Center, Kennedy Krieger Institute, Baltimore, MD, United States

It is shown that it is possible to image endogenous exchangeable proton signals in the human brain at 3T using the recently reported method of frequency labeled exchange transfer (FLEX) MRI. The results indicate that, compared to traditional CEST experiments, FLEX MRI preferentially detects more rapidly exchanging amide/amine protons, thereby changing the information content of the exchangeable proton spectrum. This has the potential to open up different types of endogenous applications as well as more easy detection of rapidly exchanging protons in diaCEST agents or fast exchanging units such as water molecules in paraCEST agents without interference of conventional MTC.