PHASE-OFFSET MULTIPLANAR (POMP) VOLUME IMAGING - A NEW TECHNIQUE

Phase-offset multiplanar (POMP) imaging is a technique that excites several sections simultaneously for improved imaging efficiency. The centers of the reconstructed images from each of the POMP sections are offset from each other in the phase-encoding direction by means of view-dependent phase modulation of the radio-frequency (RF) excitation pulses and are placed adjacent to each other in the reconstruction. With a suitable reconstruction matrix size, the images can be made nonoverlapping and stored separately. At constant imaging time, signal-to-noise ratio (S/N), and resolution, POMP imaging produces a factor N(p) more sections than a conventional sequence but with a reduced field of view. Alternatively, imaging time may be increased by the factor N(p) to retain the same field of view but with the expected S/N advantage. The average RF power deposited by the 90-degrees composite RF pulse is greater by the factor N(p), but the power for the 180-degrees pulse is unchanged. The POMP method is discussed and compared with three-dimensional and Hadamard techniques.