Safety of active auditory implants in magnetic resonance imaging

Abstract

Magnetic resonance imaging (MRI) has become the gold standard for the diagnosis of many pathologies. Using MRI in patients with auditory implants can however raise concerns due to mutual interactions between the implant and imaging device, resulting in potential patient risks. Several implant manufacturers have been working towards more MRI safe devices. Older devices are however often labelled for more stringent conditions, possibly creating confusion with patients and professionals. With this myriad of different devices that are implanted in patients for lifetimes of at least 20 years, it is crucial that both patients and professionals have a clear understanding of the safety of their devices. This work aims at providing an exhaustive overview on the MRI safety of active auditory implants. The available industry standards that are followed by manufacturers are outlined and an overview of the latest scientific developments focusing on the last five years is provided. In addition, based on the analysis of the adverse events reported to the Food and Drug Administration (FDA) and in literature within the past ten years, a systematic review of the most commonly occurring issues for patients with auditory implants in the MRI environment is provided. Results indicate that despite the release of more MRI conditional active hearing implants on the market, adverse events still occur. An extensive overview is provided on the MRI safety of active auditory implants, aiming to increase the understanding of the topic for healthcare professionals and contribute to safer scanning conditions for patients.

Keywords: ASTM, American Society for Testing and Materials; Active hearing implant; Adverse events; B0, Static magnetic field; B1+RMS, Magnitude of the radiofrequency electromagnetic field; Cochlear implant; FDA, Food and Drug Administration; ISO, International Standardization Organization; MRI Safety; MRI, Magnetic Resonance Imaging; RF, Radiofrequency; Radiology; Systematic review; TS, Technical Specification; dB/dt, Gradient magnetic field.