hide
Free keywords:
-
Abstract:
B0 fluctuations in the human brain induced by susceptibility changes during respiration were studied at 7T. In FIDs measured after a single RF pulse, a Respiration Induced Resonance Offset (RIRO) with large amplitude was consistently detected although the amplitude varied from 1.45 Hz to 4 Hz between subjects. In transverse EPI images in the occipital lobe, the RIRO amplitude showed a monotonic increase along Z-axis toward the lungs. Dynamic 3D FLASH phase maps revealed that an analytical model can describe the spatial distribution of RIRO accurately. Subsequent apparent motions in EPI series and correction strategies are discussed.