VNS Warning

[Guest guest]

" Leads, or portions of leads, often remain in the body after pulse

generators are removed, and these may act as an antenna and become

heated. "

FDA Public Health Notification: MRI-Caused Injuries in Patients with

Implanted Neurological Stimulators

(You are encouraged to copy and distribute this information)

Issued: May 10, 2005

This is to remind radiology personnel and physicians that serious

injury or death can occur when patients with implanted neurological

stimulators undergo MRI procedures, and to recommend preventive

actions.

Background

The FDA has received several reports of serious injury, including

coma and permanent neurological impairment, in patients with

implanted neurological stimulators who underwent magnetic resonance

imaging (MRI) procedures. The mechanism for these adverse events is

likely to involve heating of the electrodes at the end of the

leadwires, resulting in injury to the surrounding tissue. Although

these reports involved deep brain stimulators and vagus nerve

stimulators, similar injuries could be caused by any type of

implanted neurological stimulator, such as spinal cord stimulators,

peripheral nerve stimulators, and neuromuscular stimulators.

Recommendations

If you are a physician who implants or monitors patients with

implanted neurological stimulators:

Explain to the patient what MRI procedures are and stress that they

must consult with the monitoring physician before having any MRI

exam to find out whether it can be performed safely.

If you are a radiologist or health care professional who uses MRI

equipment:

All patients should be carefully screened for any implanted devices

prior to performing an MRI procedure, even if the implanted device

has been turned off. Also question patients about previously

implanted devices that have been removed. Leads, or portions of

leads, often remain in the body after pulse generators are removed,

and these may act as an antenna and become heated.

If the patient does have an implanted neurological stimulator,

consider consulting with the referring physician to discuss other

imaging options. For some implanted neurological stimulators,

certain MRI procedures are contraindicated and cannot be performed.

If an MRI procedure is to be performed on a patient with an

implanted neurological stimulator, be sure to review the labeling

for the specific model that is implanted in the patient, with

particular attention to warnings and precautions. The radiologist

may need to consult with the implanting or monitoring physician for

this information. Also note and follow any instructions exactly for

MRI imaging that may be in the labeling for the implant, including

information on types and/or strengths of MRI equipment that may have

been tested for interaction with the particular implanted device.

The radiologist may need to consult with the device implant

manufacturer for this information.

Reporting Adverse Events

FDA requires hospitals and other user facilities to report deaths

and serious injuries associated with the use of medical devices. If

you suspect that a reportable adverse event has occurred involving a

patient with an implanted device who has undergone an MRI procedure,

you should follow the reporting procedure established by your

facility.

We also encourage you to report adverse events related to MRI and

medical devices that do not meet the requirements for mandatory

reporting. You can report these directly to the device manufacturer.

You can also report these events to MedWatch, the FDA's voluntary

reporting program. You may submit reports to MedWatch by phone at 1-

800-FDA-1088; by FAX at 1-800-FDA-0178; by mail to MedWatch, Food

and Drug Administration, 5600 Fishers Lane, Rockville, MD 20857-

9787; or online at http://www.fda.gov/medwatch/report.htm.

Getting More Information

If you have questions about this notification, please contact

Pressly, Office of Surveillance and Biometrics (HFZ-510), 1350

Piccard Drive, Rockville, land, 20850, Fax at 301-594-2968, or

by e-mail at phann@.... You may also leave a voice mail

message at 301-594-0650 and we will return your call as soon as

possible.

FDA medical device Public Health Notifications are available on the

Internet at http://www.fda.gov/cdrh/safety.html. You can also be

notified through email on the day the safety notification is

released by subscribing to our list server. To subscribe, visit:

http://list.nih.gov/archives/dev-alert.html.

Sincerely yours,

G. Schultz, MD

Director

Center for Devices and Radiological Health

Food and Drug Administration

Updated May 10, 2005

http://www.fda.gov/cdrh/safety/neurostim.html