AN INTEGRATED PROGRAM FOR AMPLITUDE-MODULATED RF PULSE GENERATION ANDRE-MAPPING WITH SHAPED GRADIENTS

Efficient generation of amplitude modulated, frequency selective RF pu lses has been demonstrated by the Shinnar-Le Roux (SLR) algorithm. In the present article, we provide an overview of a relatively comprehens ive computer program that includes a version of the SLR algorithm and also incorporates an algorithm for re-mapping a selective RF pulse ont o a new dwell time with modulated gradients. The re-mapping may be use d to reduce SAR, or to shorten the RF pulse time by increasing the gra dient and RF strength in regions where the original RF pulse amplitude was low. The program includes additional useful features including a Bloch equations algorithm, and pulse scaling, to enable examination of pulse profiles under a variety of conditions such as RF inhomogeneity and even nuclear relaxation. The program, MATPULSE, was developed wit h the MATLAB for Windows programming language and makes extensive use of the MATLAB graphical user interface (GUI) features to generate a us er-friendly interface. A number of examples are provided to illustrate the capabilities of the MATPULSE program.