A New Method for Quantifying Chemical Exchange Rates from CEST MRI Using the Solutions to the Time-Dependent Bloch Equations with and Without Spin Locking

Kenya Murase¹, Junpei Ueda¹, Koji Itagaki¹, Shigeyoshi Saito¹, Atsuomi Kimura¹

Recently, there have been an increasing number of studies that have used the chemical exchange effect to probe the tissue microenvironment. Most of these studies adopted either a chemical exchange saturation transfer (CEST) or a spin-locking (SL) approach. We presented a simple and fast method for solving the time-dependent Bloch equations in CEST MRI with SL, and proposed a new method for quantifying chemical exchange rates from CEST MRI with and without SL using this method. Our results suggest that the CEST MRI with SL is more reliable than that without SL for quantifying chemical exchange rates.