Tuning and amplification strategies for intravascular imaging coils

The manufacturing of intravascular imaging coils poses several challenges. Due to their size, it can be difficult to incorporate local matching networks and signal amplifiers. The goal of this study is to investigate tuning and amplification strategies for intravascular coils and to assess the signal‐to‐noise benefits of incorporating a matching network and/or miniature amplifier into catheter‐based intravascular imaging devices at various locations in the signal chain. The results suggest that the use of a low‐noise amplifier close to the receiving coil enables the use of miniature coaxial cables to be used despite being noisy. Moreover, an improvement in the signal‐to‐noise ratio of over 75% is presented over conventional intravascular coil configurations where the matching circuit and low‐noise amplifier are placed at the proximal end. Therefore, designing devices for intravascular applications capable of generating high signal‐to‐noise ratio images becomes more feasible, also allowing for significant reductions in scan time. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.

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