Abstract
In magnetic resonance imaging (MRI), the electrical performance of the RF coil is critical to achieve sufficient signal to noise ratio (SNR), especially when microscopic structures [about (100 μm)3] have to be observed. In this field of application, we have developed a device (microcoil) based on the original concept of monolithic resonator, dedicated to superficial region imaging (human skin) or small animal imaging. This paper presents the developed process based on micromoulding. Flexible thin films of polymer have been used as dielectric substrate so that the microcoil could be form-fitted to non-plane surfaces. First, electrical characterizations of the RF coils have been performed. The results were compared to the expected values. A flexible RF coil of 15 mm diameter was then used to perform proton MRI of a saline phantom. When the coil was form-fitted to the phantom surface, a maximum SNR gain of 2 was achieved with respect to identical but plane RF coil. Finally, the flexible coil was used to perform MRI in vivo with high spatial resolution on a mouse using a small animal dedicated scanner operating at 2.35 T.
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Acknowledgments
This work was supported by grant from French Ministry of Research (RNTS 2001) and grant of the University Paris South (PPF).
The authors also thank for their financial support the Conseil Général de l’Essone through the use of the equipments of the Centrale de Technologie Universitaire (IEF-MINERVE).
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Work originally presented to DTIP 2006 Conference.
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Woytasik, M., Ginefri, JC., Raynaud, JS. et al. Characterization of flexible RF microcoils dedicated to local MRI. Microsyst Technol 13, 1575–1580 (2007). https://doi.org/10.1007/s00542-006-0277-x
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DOI: https://doi.org/10.1007/s00542-006-0277-x