Premium
An optical system for wireless detuning of parallel resonant circuits
Author(s) -
Wong MSE E. Y.,
Zhang PhD Q.,
Duerk PhD J. L.,
Lewin MD J. S.,
Wendt PhD M.
Publication year - 2000
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/1522-2586(200010)12:4<632::aid-jmri17>3.0.co;2-j
Subject(s) - photoresistor , electromagnetic coil , inductor , electronic circuit , capacitor , rlc circuit , optoelectronics , materials science , photodetector , electrical engineering , computer science , physics , engineering , voltage
Abstract A new optical method of detuning parallel resonant circuits is described. This method involves the integration of a photoresistor in parallel with the inductor and capacitor of a parallel resonant circuit, in this case a magnetic resonance imaging (MRI) receiver coil. A fiberoptic cable extending the length of the interventional device is used in conjunction with an external light source to deliver light to the photoresistor. Exposing the photoresistor to light changes its bulk resistance and greatly lowers the Q of the parallel resonant circuit, effectively detuning it. By combining this optical detuning scheme with inductive coupling of the interventional device‐mounted microcoils to a standard MRI coil, a completely wireless device for active device tracking has been created. This new device improves on current technology by simplifying device complexity and reducing patient risk by eliminating the need for electrical connections between the device‐mounted microcoils to the MR receiver channel. J. Magn. Reson. Imaging 2000;12:632–638. © 2000 Wiley‐Liss, Inc.