Exponent performs compatibility testing of medical devices using magnetic resonance imaging (MRI). Through our
A2LA-accredited laboratory we assist medical device manufacturers in validating MRI safety and compatibility design requirements and regulatory labeling requirements.
We have performed MRI testing on a variety of cardiovascular devices and provided analysis and guidance to clients with regard to FDA submission in the context of performance to standards. Exponent’s analytical techniques allow manufacturers to determine the risks associated with already-implanted devices and to formulate a strategy for serving the needs of users and patients. Recently, Exponent conducted testing on a range of nitinol stents, some of which exhibited localized radiofrequency heating. Exponent provided analysis and labeling guidelines for use in formulating a strategy for marketing the devices and to guide submissions to regulatory authorities.
We have the capability—and are accredited to ISO 17025—to test at 1.5T and 3.0T with both wide-bore and conventional-bore configurations in accordance with all applicable ASTM standards (listed below). Exponent also has arrangements with regional research institutions to conduct studies at high field strength, if needed.
Standards
ASTM F2052 – Standard Test Method for Measurement of Magnetically Induced Displacement Force on Medical Devices in the Magnetic Resonance Environment
ASTM F2119 – Standard Test Method for Evaluation of MR Image Artifacts from Passive Implants
ASTM F2182 – Standard Test Method for Measurement of Radio Frequency Induced Heating Near Passive Implants During Magnetic Resonance Imaging
ASTM F2213 – Standard Test Method for Measurement of Magnetically Induced Torque on Medical Devices in the Magnetic Resonance Environment
Medical Devices Interacting with Magnetic Resonance
- Electrophysiology devices: pacemakers, implantable cardioverter defibrillators
- Neurointerventional devices: aneurism clips and coils, hydrocephalus valves/shunts, neurostimulators
- Vascular implants: stents, valves, filters
- Interventional instruments: catheters, guidewires, endoscopes
- Orthopaedic/spinal devices: joint prostheses, fracture fixation hardware, fusion and deformity constructs
- Medical monitoring instrumentation
- Others: handheld surgical instruments, implantable (cochlear) hearing devices
Figure 1. Sample under test per ASTM 2119 to determine artifact size
Figure 2. Siemens 3T MRI
Figure 3. ASTM F2182 Phantom used to characterize radiofrequency-induced heating