SPIO: Positive contrast by adiabatic IRON using repetitve inversion pulses

Introduction Superparamagnetic iron oxide particles (SPIO) have been shown to accumulate in lymph nodes and macrophages, e.g. within atherosclerotic plaque. [1-2] Susceptibility weighted imaging is the most sensitive means to detect the particles, however the lack of signal caused by the magnetic dipole field perturbations is ambiguous, as numerous other sources of signal loss exist. To overcome this problem, so called "brightiron" or "off-resonance imaging" techniques have been proposed. [3-5] Here we describe a further development of the IRON method [5].