Release date: May 6, 2013
The manufacturer of deep brain stimulation (DBS) devices used in the USA and internationally, Medtronic, Inc., of Minneapolis, Minnesota, announced on May 2nd a risk of damage to DBS devices associated with the use of a component used in DBS surgery. The FDA classified this as a Class I Recall indicating high risk to patients. Medtronic had notified physicians of this issue in February.
The component, called the “lead cap" is used to temporarily protect the wire that connects the electrode to the battery pack (the “lead”) during the time between the surgery to implant the electrode and the later procedure to implant the neurostimulator or implanted pulse generator, often called the battery, which generates the electrical pulses that are emitted by the electrode. When the battery is implanted, the lead cap is removed and discarded. Note that this is not the permanent “cap" that is placed over the site where the electrode passes through the skull.
If you have a Medtronic DBS device should you be worried about the “lead cap” recall and what should you know?
This issue could possibly affect Parkinson'sdisease and also other patients with implanted devices. Between placing the electrode in the brain and implanting the battery, a neurosurgeon will sometimes temporarily protect the exposed wire or “lead” with a “lead cap,” to protect the lead until the battery is implanted. After the battery is implanted, the lead cap is discarded. It is estimated that only about 20 percent of surgeons even use this cap. The risk is that if the surgeon tightens a screw too tightly on the lead cap, it may damage lead and affect the functioning of the DBS hardware. All implanting neurosurgeons have been made aware of the issue, and a solution is under review by the FDA.
Why did the FDA recall Medtronic devices?
According to Medtronic, they received reports of DBS leads being damaged due to over-tightening of the screw that holds the lead cap in place. The DBS lead cap may be used in DBS and dystonia therapy kits temporarily to protect the end of a DBS lead after it has been implanted. The DBS lead cap is not used in all DBS procedures, and is not permanently implanted. If the lead is damaged, lead replacement may be required or optimal therapy may not be achieved. Only a small number of patients are expected to require lead replacement.
What do patients and families need to know about this issue?
- Any damage to the DBS system can be assessed in a minute or two by your doctor in the office setting through use of a portable programming device that can check the integrity of the system. If you have a sudden worsening of your symptoms you should visit your doctor and have the device checked for possible damage.
- It is estimated that only a small percentage of DBS systems have been damaged by the lead cap.
- Because the DBS system has four small lead contacts that can be used to deliver electricity, it is possible that even if the DBS system is damaged, a different contact can be used for stimulation.
Should I see my doctor to have it checked out?
The damage from this current cap issue occurs at the time of DBS implantation, so patients who have had DBS devices implanted for a while and have been doing well on their therapy should not worry about this recent FDA recall.
Patients can double check their DBS devices for damage during their regular doctor visits. Remember that DBS devices can be damaged after implantation and this damage (fractures and short circuits), if it occurs, will most likely not be the result of this current capping issue which has been addressed by the FDA.
If I have DBS, what should I do? Will someone call me?
Any malfunctions or adverse events related to a device should be reported to Medtronic Neuromodulation Technical Services at 1-800-707-0933, weekdays from 7 a.m. to 6 p.m. CST, and the FDA's MedWatch Program at http://www.fda.gov/MedWatch.
I have one of the devices recalled. Will I have to have surgery?
In the case of lead damage, if at the beginning of therapy patients are receiving therapy as expected, they are not likely to be affected by this issue. Patients with questions relating to this issue are encouraged to talk with their physicians.
I am considering DBS surgery, will it affect me? Should I hold off?
No, a manufacturing change intended to address the issue is currently under FDA review, and in the meantime Medtronic has issued modified instructions to physicians who may use DBS lead caps.