BAHA devices and magnetic resonance imaging scanners

Area of Science:

• Medical Devices
• Audiology
• Radiology

Background:

• Patients with Bone-anchored Hearing Aid (BAHA) systems may need MRI scans.
• Assessing the safety of BAHA systems in MRI environments is crucial for patient care.

Purpose of the Study:

• To evaluate the magnetic field interactions of the BAHA System fixture and abutment.
• To determine the safety and potential image artifacts of BAHA System devices during 9.4-Tesla MRI exposure.

Main Methods:

• Testing BAHA System fixtures (3 and 4 mm abutments) in Petri dishes and human cadaver temporal bones under a 9.4-T MRI magnet.
• Observing the external BAHA processor's behavior in the MRI suite.
• Reviewing MRI scans of two patients with BAHA devices at 1.5 T and 3.0 T.

Main Results:

• The BAHA System fixture and abutment did not move in cadaver temporal bone models.
• The external BAHA processor exhibited significant movement towards the magnet.
• Patient MRIs showed no adverse effects, with image quality unaffected beyond 1 cm from the BAHA post.

Conclusions:

• The bone-mounted BAHA System fixture and abutment are safe up to 9.4 T, resisting magnetic displacement.
• MRI scanning of patients with BAHA Systems is safe at field strengths up to 3.0 T and likely higher.
• Minimal artifactation around the BAHA post allows for excellent image quality at a distance.