  In Magnetic Resonance Imaging (MRI), to achieve sufficient Signal to Noise
Ratio (SNR), the electrical performance of the RF coil is critical. We
developed a device (microcoil) based on the original concept of monolithic
resonator. This paper presents the used fabrication process based on
micromoulding. The dielectric substrates are flexible thin films of polymer,
which allow the microcoil to be form fitted to none-plane surface. Electrical
characterizations of the RF coils are first performed and results are compared
to the attempted values. Proton MRI of a saline phantom using a flexible RF
coil of 15 mm in diameter is performed. When the coil is conformed to the
phantom surface, a SNR gain up to 2 is achieved as compared to identical but
planar RF coil. Finally, the flexible coil is used in vivo to perform MRI with
high spatial resolution on a mouse using a small animal dedicated scanner
operating at in a 2.35 T.
