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! The safety and efficacy of this therapy have not been systematically
established for uses not covered in the “Intended Use / Indications” section of
this manual or in patients with the following conditions:
♦ Cardiac arrhythmias or other abnormalities
♦ History of dysautonomias
♦ History of previous therapeutic brain surgery
♦ History of respiratory diseases or disorders, including dyspnea and asthma
♦ History of ulcers (gastric, duodenal, or other)
♦ History of vasovagal syncope
♦ Neurological diseases other than epilepsy
♦ Only one vagus nerve
♦ Other concurrent forms of brain stimulation
♦ Pre-existing hoarseness
♦ Pregnancy or nursing

! Pre-clinical Study, Teratogenic Effects: There are no adequate and wellcontrolled
studies of VNS Therapy in pregnant women. Reproduction studies
have been performed using female rabbits stimulated with the commercially
available VNS Therapy System at stimulation dose settings similar to those used for humans. These animal studies have revealed no evidence of impaired
fertility or harm to the fetus due to VNS Therapy. Because animal
reproduction studies are not always predictive of human response and animal
studies cannot address developmental abnormalities, VNS should be used
during pregnancy only if clearly needed. Although the operating ranges of the
VNS Therapy System and fetal monitors are dissimilar and no interaction
would be expected, testing has not been performed. Therefore, the potential
may exist for interaction between the VNS Therapy System and fetal
monitoring systems.

Additionally, further studies are planned for systematically establishing the
therapy’s use in the United States in patients younger than 12 or older than 60,
and in those with primary generalized seizures.


12.1.3. Uses of the Magnet

There are four possible uses of the magnet:
♦ To provide on-demand stimulation as an attempt to abort or deintensify
an oncoming seizure
♦ To temporarily inhibit stimulation
♦ To reset the Pulse Generator (in combination with the Programming
Wand)
♦ To test daily the functioning of the Pulse Generator
Cyberonics recommends that patients be instructed to use the magnet to activate
stimulation during an aura or at the start of a seizure. Magnet activation may be
initiated by the patient, a companion, or the physician by applying or passing a
magnet over the Pulse Generator to activate a reed switch in the Pulse Generator’s
electronic circuitry. This action changes the Pulse Generator from Normal Mode
to Magnet Mode. Two identical magnets, each providing a
minimum of 50 gauss at one inch, are supplied by Cyberonics. A CyberWatchTM
(watch-style) magnet attaches to a wristband just as a wristwatch would and a
CyberPagerTM (pager-style) magnet attaches to a belt much as a pager with quickrelease mechanism would.

! Label side of magnet should face the Pulse Generator while activating or
stopping stimulation.

All magnets may lose their effectiveness over time. Avoid dropping the magnets
or storing them near other magnets.

12.1.3.2. Inhibiting Pulse Generator Output with a Magnet
Application of the magnet during stimulation will inhibit the output. In addition,
holding the magnet in place for at least
65 seconds will prevent the initiation of a Magnet Mode stimulation and will
terminate any ongoing Normal Mode stimulation. After the magnet is removed,
Normal Mode operation will resume with stimulation when one complete OFF
time has elapsed. In the unlikely event of continuous stimulation or other
malfunction, the patient must be advised to apply the magnet, secure it in place,
and immediately notify his or her physician.
! If stimulation becomes painful, the patient should be instructed to stop the
stimulation with the magnet.

! Bipolar Lead replacement or removal because of lack of efficacy is a
medical judgement based on the patient’s desires and health status, and must
be carefully weighed against the known and unknown risks of surgery. At
present, there are no known long-term hazards or risks associated with
leaving the Bipolar Lead implanted, beyond those already mentioned in this
manual.

12.1.5. Follow-up Information
12.1.5.1. Guidelines for Patient Follow-up
During the first few weeks after implantation, the patient should be seen to
confirm wound healing and proper Pulse Generator operation. The Pulse
Generator’s output current for both the magnet and the programmed stimulation
must be 0.0 mA for the first 14 days after implantation.

The NCP System is an adjunctive therapy to existing (prior to device
implantation) antiepileptic medications. Cyberonics strongly encourages
physicians to keep all antiepileptic medications stable for the first three
months of stimulation before attempting to reduce or change a patient’s
medication.

During initial programming, the output current should be programmed to start at
nominal parameters (0 mA) and then be slowly increased in 0.25 mA increments
until the patient feels the stimulation at a comfortable level. Patients who are
receiving replacement generators should also be started at nominal parameters,
with 0.25 mA-step increases to allow
re-accommodation.

Cyberonics recommends that testing of the magnet output be performed while the
patient is still in the physician’s office to ensure tolerability of the magnet output.
The magnet output should be programmed at each visit, if necessary, to a level
that is perceptible to the patient.

Some patients have reported that it is easier to verify daily that stimulation is
being delivered if the magnet output current is set to one step above normal
stimulation settings. This slightly higher output current is intended to allow
patients who have accommodated to normal stimulation to recognize or perceive
the magnet stimulation, thereby confirming device function.

At each patient visit, the Pulse Generator should be interrogated using the
appropriate version of the NCP Programming Software. After reprogramming
and/or diagnostics testing, data should be printed out and filed (see the NCP
Programming Software physician’s manual for instructions on printing out data).
These data can be used for comparison with a patient’s diary or own records to
evaluate NCP System therapy, to confirm proper NCP System functioning, and to
assess the need for reprogramming.

The average output current used during the clinical studies was
about 1.0 mA. Other standard treatment settings were 30 Hz,
500 ìsec pulse width, 30 sec ON time, and five min OFF time. There are no data
to verify that these are optimal parameters.

There is no proven correlation at present between high output current (m
Amps) and device effectiveness, nor is there a standard treatment level that
needs to be achieved during treatment ramping. NCP System treatment should not
be uncomfortable, nor should it cause bothersome side effects. Patients should be
observed for at least 30 minutes after the last stimulation adjustment to make
certain that they are comfortable with both magnet-activated and programmed
stimulation.

Although Cyberonics recommends adjusting output current as necessary, there are
no controlled data at this time to indicate that higher current levels are associated
with better efficacy. Patients whose seizures are well controlled at follow-up
should not have their settings changed unless they experience uncomfortable side
effects.

The subsequent follow-up schedule and the nature of each examination should be
determined by the physician on the basis of patient response to and tolerance of
the implant. In all other respects, follow-up should be performed in accordance
with the standard medical practice for patients with epilepsy.