Development of a ring cavity-based fibre optic sensor for MR-compatible medical sensing applications

Advances in robotic systems and rapid developments in minimally invasive surgery (MIS) have made their use possible in the operating room due to many distinct advantages offered by MIS over conventional surgical procedures. The constant increase of medical examinations, surgeries and surgical interventions using intraoperative guidance with magnetic resonance imaging (MRI) has promoted research on new sensors to be applied in this scenario. However, due to the challenging environment under MRI system limits the applicability of materials and traditional electronic sensors. Optical fibres are small in size, chemically inert, immune to electromagnetic interference and offer the real-time in vivo multi-parameter measurement capability. Herein, we report a ring cavity-based fibre optic sensor design using MR-compatible polymer material. Optical fibres were used to excite surface resonance modes (SRM) of the ring cavity-based sensor. The paper reports initial investigations on ring cavity based MR-compatible fibre optic sensor design. Computational simulations were carried out to study the effect of structural and material parameters on the sensor design. Ring cavity was developed using polymethyl methacrylate. Developed ring cavity will be used to develop the MR-compatible fibre optic sensor for medical applications.