MR Imaging and Cochlear Implants with Retained Internal Magnets: Reducing Artifacts near Highly Inhomogeneous...

Area of Science:

• Medical Imaging
• Neurosurgery
• Otolaryngology

Background:

• Cochlear implants and auditory brainstem implants are increasingly used for severe to profound sensorineural hearing loss.
• These devices contain internal magnets essential for external speech processor attachment.
• Regulatory approval allows MRI with certain cochlear implant models under specific conditions.

Purpose of the Study:

• To address the challenges of MRI artifact generation caused by internal magnets in cochlear and auditory brainstem implants.
• To discuss strategies for optimizing MRI examinations in patients with these implants.
• To highlight the importance of multidisciplinary collaboration for effective patient management.

Main Methods:

• Review of MRI artifact types associated with cochlear and auditory brainstem implants.
• Discussion of techniques to mitigate magnetic field inhomogeneities and susceptibility artifacts.
• Exploration of patient comfort and safety considerations during MRI.

Main Results:

• Internal magnets in implants cause significant MRI artifacts, degrading image quality.
• Artifacts are particularly problematic in diffusion-weighted and accelerated imaging sequences.
• Impromptu adjustments and head wraps are often necessary but may not fully prevent displacement.

Conclusions:

• Effective MRI in patients with cochlear and auditory brainstem implants requires tailored strategies to manage artifacts.
• Collaboration among radiologists, technologists, and physicists is crucial for customizing examinations.
• Optimized imaging facilitates accurate diagnosis and monitoring, particularly for conditions like neurofibromatosis type 2.