It is intended to provide a Magnetic Resonance Imaging (MRI) phantom for
.sup.1H/.sup.19F signal detection that permits the stable and uniform
dispersion of a vesicle and to accomplish the adjustment of a measurement
parameter for a .sup.1H/.sup.19F signal and performance confirmation by
use of the phantom. The present invention provides an MRI phantom having
a gel comprising a vesicle comprising at least one of a perfluorocarbon
and a superparamagnetic iron oxide particle and an MRI system having the
phantom.