First data from study of occipital nerve stimulation to control
chronic migraine
7 July 2008
Data from a multi-centre study using neurostimulation of the
occipital nerves as a potential approach to treating medically
refractory chronic migraines was presented at the annual scientific
meeting of the American Headache Society (AHS) in June.
The Medtronic-sponsored study, called Occipital Nerve Stimulation for
the Treatment of Intractable Migraine (ONSTIM), included patients who
had regularly experienced 15 or more headache days per month that were
not responsive to conventional medical therapies.
The ONSTIM study, conducted under an investigational device exemption
(IDE), collected electronic diary data from 66 patients from nine
centres who were followed for three months. The data reported at the AHS
meeting include the average change in the number of headache days per
month, overall pain intensity and the responder rate based on at least a
50% reduction in headache days per month or at least a three-point
reduction in overall pain intensity.
“The ONSTIM results suggest that occipital nerve stimulation, or ONS,
may be a promising therapy option for individuals who have not had
success in treating their chronic migraine and as a result are living
with the painful and often debilitating symptoms,” said Dr Joel Saper,
founder and director of the Michigan Head Pain and Neurological
Institute, Ann Arbor, Michigan, and principal investigator for the
ONSTIM study.
“While ONS for chronic migraine requires additional clinical
evaluation, our early experience in this study is encouraging and
indicates that ONS could possibly help some chronic migraine patients
who have exhausted other treatment options.”
In the study, thin lead wires were placed under the skin near the
occipital nerves, which arise from the spinal cord and branch out across
the back of the head carrying sensory signals from that region to the
brain. The leads were connected to an implanted Medtronic
neurostimulator that delivered controlled electrical pulses to the
occipital nerves.
Patients were randomised to three groups to receive: either a
neurostimulator and have the ability to control the level of
stimulation; or a neurostimulator as part of a device control group; or
only standard medical management instead of an ONS implant.
A positive response was defined as at least a 50% reduction in the
number of headache days in a month, or a reduction in the pain intensity
of at least three points on a standard 0-10 pain scale. In addition to
evaluating the efficacy of ONS therapy, the ONSTIM trial was designed to
follow patients out to three years related to safety.
“We are pleased to be the first to present randomised, controlled
data on ONS for intractable chronic migraine, where there is a large
unmet medical need not currently addressed by medication or other
therapies,” said Richard Kuntz, MD, corporate senior vice president and
president of the Neuromodulation business at Medtronic.
“We plan to apply our expertise and long-standing history in
neurostimulation for chronic pain to pursue additional studies of the
ONS approach for those who suffer from these persistent and highly
debilitating migraines.”