Occipital Nerve Stimulation for Migraine and Headache Prevention - 2008 Update
The use of occipital nerve stimulation (ONS) for the prevention of Migraines and headaches is in clinical trials and has been of great interest to those sufferers with intractable Migraines and headaches that do not respond well to treatment. The first clinical trial data has now been released, shedding some light on how well the treatment works and what may lie ahead.
What is occipital nerve stimulation (ONS)? ONS involves delivering a small electrical charge to the occipital nerve to prevent Migraines and headaches in patients who have not responded to medications. ONS is not effective for all patients, and a trial of occipital nerve block injections is often a good indicator of ONS suitability for specific patients.
The basic hardware of the ONS systems consists of a lead with electrodes and contacts which is connected to a separatelyimplanted impulse generator by a wire. 1
Dr. David Dodick has summarized the progress of ONS research to date (June, 2008):
"Over the past 6 years, occipital nerve stimulation has emerged as a potential treatment option for a variety of different intractable primary headache disorders... Open-label prospective studies and case series evaluating the efficacy and safety of ONS in patients with medically refractory chronic migraine, chronic cluster headache, and hemicrania continua have been reported (refs). The favorable results from these preliminary open studies have prompted three randomized, sham-controlled studies in patients with refractory chronic migraine (PRISM NCT00286078 (Advanced Bionics), ONSTIM (Medtronic Inc.), Advanced Neurostimulation Systems). Results from these studies are anxiously awaited and expected over the next 24 months."1
Neurostimulation, including ONS, is not yet FDA approved for the treatment of Migraine disease or other headache disorders, but the clinical trials are progressing. The biggest of these clinical trials is the Occipital Nerve Stimulation for the Treatment of Intractable Migraine (ONSTIM) sponsored by Medtronic, which included patients who have regularly experienced 15 or more headache days per month that were not responsive to conventional medical therapies.
ONSTIM Study Details: 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 randomized to three groups to receive: either
- a neurostimulator and have the ability to control the level of stimulation
- a neurostimulator as part of a device control group
- only standard medical management instead of an ONS implant.
- A positive response was defined as at least a 50 percent 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.
- Slippage of lead wires was the most common adverse event.
- In addition to evaluating the efficacy of ONS therapy, the ONSTIM trial was designed to follow patients out to three years related to safety.
Dr. Joel Saper, founder and director of the Michigan Head Pain and Neurological Institute, Ann Arbor, Mich., and principal investigator for the ONSTIM study, stated,
"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... 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."3
Summary and Comments:
Early results of the ONSTIM trial look promising for patients with intractable Migraines and headaches. Additional ONS studies are ongoing, and their results are anxiously awaited.
Patients considering ONS treatment should be aware of some key points:
- ONS is not appropriate for all patients.
- Occipital nerve block injections may be a good predictor of whether OSN is suitable for individual patients.
- ONS is not yet FDA approved for Migraine and headache prevention, but may be prescribed off-label (as many medications are).4
- Since ONS is not FDA approved, most insurance companies will not pay for this treatment.4
- Some doctors are coding insurance forms for conditions other than Migraine or headache in order to get insurance company approval and payment. It should be noted that this is an illegal practice that could result with patients having an additional condition (that they don't have) listed on their medical records. If ONS is approved based on a condition the patient does not have, insurance companies can rescind payment and/or take legal action.4 A leading Migraine specialist who wishes to remain unnamed commented, "It's a sad state of affairs. A less trained doctor may misdiagnose a chronic Migraine patient as having another condition, say occipital neuralgia, and with that misdiagnosis, get the insurance company to pay for ONS. Another doctor may knowingly falsify the forms and list occipital neuralgia as the diagnosis to get ONS covered by the patient's insurance. Yet the doctor who correctly lists the diagnosis as chronic Migraine cannot get the insurance company to pay. It's a case where diagnosing correctly and completing the forums honestly results in the treatment not being covered by most insurance companies.5
It should also be noted that, contrary to the sensationalized headlines coming from some mainstream media outlets, ONS is not a cure for Migraine disease. It can be an effective preventive treatment for some patients, but it addresses only some Migraine triggers, not all. Thus, patients using ONS may see a reduction in Migraine and headache frequency, but not a complete cessation of Migraines and headaches.
1 Dodick, David W., MD. "Occipital Nerve Stimulation." Platform Presentation. American Headache Society's 50th Annual Scientific Meeting. Boston. June 27, 2008.
2 Goadsby, Peter J., MD. "Neurostimulation in primary headache syndromes." Expert Rev. Neurotherapeutics 7(12), 1785-1789 (2007).
3 Press Release. "Medtronic Announces First Clinical Data on Occipital Nerve Stimulation for Chronic Migraine to be Presented at American Headache Society Meeting." Medtronic. Minneapolis. June 27, 2008.
4 Interview with Sheila Brown, FDA Center For Devices and Radiological Health. June 10, 2008.
5 Interview with unnamed leading Migraine and headache specialist. June 28, 2008.