Important Safety Alerts

The United States Food and Drug Administration (FDA) is providing information about the potential for increased image artifact associated with Magnetic Resonance Angiography (MRA) imaging for patient follow-up of certain post neurovascular embolization coil procedures

Information reviewed by the FDA, including FDA's Medical Device Reports (MDRs), information from device manufacturers, and published literature, indicates that when MRA is performed on patients implanted with neurovascular embolization coils containing 304V stainless steel (either as part of the coil implant itself, or left behind as part of the detachment process), the images may contain larger than expected MR artifact, or image voids when compared to other metals. In these cases, the reduced quality of the MRA image from increased artifact can result in inaccurate clinical diagnoses (e.g., occlusion status) and subsequent inappropriate medical decisions.

Most neurovascular embolization coils currently on the market are labeled as Magnetic Resonance (MR) Conditional. The MR Conditional information in the product labeling conveys to the user the conditions of safe use of the device when scanned within an MR environment. The product labeling for neurovascular embolization coils does not currently convey the extent of MRA image artifact caused by the device or the MRA imaging parameters that will yield the lowest amount of image artifact if MRA is used for patient follow-up.

The FDA recommends that health care professionals:

• Be aware of the presence of 304V stainless steel in the coil system(s) typically used. If uncertain, the applicable device manufacturer should be contacted for information about the coil, its detachment mechanism, and any specific recommendations regarding the use of MRA with their product.
• Understand that 304V stainless steel-containing embolization coil systems may increase image artifact on MRA exams performed at the time of aneurysm follow-up. In these situations, X-ray based DSA should be considered.
• If choosing to use MRA for follow-up, utilize optimal imaging parameters to minimize image artifact, including:
  • Shortest echo times
  • High readout bandwidth
• In addition, ensure that the MRI system at their site meets all conditions provided in the MRI conditional labeling of the coil system.

For details, please refer to the FDA website:
https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm600565.htm
https://www.fda.gov/MedicalDevices/Safety/LetterstoHealthCareProviders/ucm600627.htm

Posted on 14 March 2018