Development of high-resolution intraluminal and intravascular MRI probe using microfabrication on cylindrical substrates

The objective of this study is development of high-resolution intraluminal and intravascular MRI probe using microfabrication on cylindrical substrates. MRI holds promise for in vivo characterization due to its potential for obtaining high-resolution images and its sensitivity to the compositional characteristics of lesion. By placing a receive coil in the human body, NMR signals from the tissue surrounding the coil can be detected sensitively and the method enables in vivo high-resolution imaging (high spatial resolution and high spectroscopic resolution). The preferable receive coil has homogeneous RF receptivity around the probe and high-SNR. Novel coil designs and/or multi-coil have capabilities to meet these demands. To connect the tuning/matching circuit and amplifier circuit near the coil is needed to improve SNR of the system. Microfabrication on cylindrical substrate is one of methods for fabricating arbitrary coil pattern and the tuning/matching circuit on the tube with small diameters. Using a maskless lithography technique, solenoid coil, tilted coil and saddle shaped coil have been fabricated on glass tube with 2 mm O.D.. Imaging test of the coils were performed on 3 T MRI in a 2% agar phantom.