A Novel Three Dimensional Radiofrequency Pulse for Small Voxel Excitation

Natee Ina¹, Suwit Saekho^1,2

The three dimensional Radio Frequency pulse (3D RF) has benefit to many applications. The major limitation of this pulse is long pulse length. A novel 3D RF pulse design was based on the small tip angle approximation combining the multi-shot and the half-pulse scheme for a small volume excitation. Numerical integration of the Bloch equation demonstrated that the two shot pulses along the x-y direction weighted with two half pulses along z- direction for cylindrical excitation at the diameter and thickness of 12 mm and 10 mm respectively, provides 34% shorter pulse width compared to that of conventional two-shot pulse.