Near field communication (NFC) device: Evaluation of MRI issues

Near field communication (NFC) is a wireless, short-range, secure communication technology that may be used for healthcare-related applications. An NFC device was recently developed that was intended for implantation in the dorsal fascia, above the interosseous compartment of the hand. This implant uses a ferrite rod to increase the distance of communication between devices. The purpose of this investigation was to evaluate MRI issues for this NFC device using standardized techniques and well-accepted methodology.

The NFC device (Vivokey Spark 2, Cryptobionic Implant, Vivokey Technologies, www.vivokey.com) was assessed for magnetic field interactions (force and torque) at 3-Tesla, magnetic field interactions according to the simulated intended use of the implant, MRI-related heating at 1.5-Tesla/64-MHz and 3-Tesla/128-MHz, functional change associated with MRI conditions at 1.5-Tesla/64-MHz and 3-Tesla/128-MHz, and artifacts at 3-Tesla.

The mean deflection angle was 90° ± 0 and torque was "positive". However, tests evaluating the simulated intended use of the NFC device demonstrated no movement, displacement, or rotational alignment. The highest temperature changes at 1.5-Tesla/64-MHz and 3-Tesla/128-MHz were 1.7 °C and 1.9 °C, respectively. There was no change in the operational capabilities of the NFC device related to the MRI exposures. Artifacts were relatively large in comparison to the size of the NFC device.

The findings indicated that the particular NFC device that underwent evaluation is "MR Conditional" for a patient undergoing MRI at 1.5-Tesla or 3-Tesla, operating the scanner in the Normal Operating Mode (i.e., default whole-body averaged SAR of 2.0-W/kg). Notably, this is the first NFC device evaluated for MRI-related issues.