The Future of Neuromodulation
Rashmi Halker, M.D. shares how neuromodulation provides a non-invasive option for migraine and headache treatment.
Neuromodulation provides a non-invasive treatment option for headache and migraine patients. We recently spoke with Rashmi Halker, M.D., F.A.H.S., an Assistant Professor of Neurology at the Scottsdale, AZ campus of the Mayo Clinic about the existing neuromodulation technologies and her hopes for their future developments.
Tell us about neuromodulation and the current devices available.
Neuromodulation involves the use of a device that uses current or magnets to modulate or change brain activity. There are several different neuromodulation devices at the moment, either available for clinical use or currently being trialed. They’re working on different nerves, different peripheral nerves, to see if we can use them to affect migraine. There are supraorbital simulators, transcranial magnetic stimulators that you apply to the back of your head, there’s a vagus nerve stimulator in the neck, and several others as well.
How do these neuromodulation devices work to treat headache disorders like migraine?
They all work differently, but the basic idea is that they’re manipulating different peripheral nerves to influence the migraine pathway. For example, the single-pulse transcranial magnetic stimulator is an easy, handheld device that is currently FDA approved for the acute treatment of migraine with aura, and FDA approved as a preventative treatment after studies found it helpful in reducing migraine frequency. It’s very easy to use: You turn it on, you put it behind your head, push a button, and it generates a magnetic impulse, which is supposed to change the electrical connections within the brain and therefore, modulate migraine. Patients tend to tolerate it very well, although I usually don’t recommend it for patients who have subcutaneous allodynia. I think it works. For some people, they find it to be very helpful. It’s a nice option when patients either can’t or don’t want to use medications.
What FDA-approved devices are available currently?
The one you use on your neck is called the vagus nerve stimulator, more commonly known by its brand name, gammaCore. It’s a noninvasive handheld tool that, until recently, had only been approved by the FDA for as-needed treatment of episodic cluster headache. In late January, the device received an additional FDA approval for the acute treatment of migraine.
Another FDA-approved device is a supraorbital transcutaneous stimulator, known by the brand name Cefaly. Cefaly manufactures three different devices: The Cefaly Prevent, the Cefaly Acute and the Cefaly Dual. Cefaly Prevent is their oldest device; it’s used for migraine prophylaxis. The Cefaly Acute and Cefaly Dual devices are new. The Acute device recently received FDA approval for the acute treatment of migraine, following an open label and a double-blind study that both confirmed its efficacy. The dual device is the newest device, and it is used for both preventive and acute treatment of migraine.
What about the non-FDA approved devices?
There are new devices currently in clinical trials. There’s a caloric vestibular stimulator, which looks like a pair of headphones you stick in on your head. There’s a probe that goes in your ears; it’s supposed to work on that nerve. There are several others also in clinical trials, too, that work on either occipital nerves or supraorbital nerves. There’s a relatively long list of things that people are looking at, at the moment. They’re not yet clinically available for patients to obtain.
Do some patients benefit from neuromodulation more than others?
I think they do, although I don’t think it’s easy to predict which patients would be more likely to respond. These devices can be pretty expensive, even the ones that are FDA approved, because insurance companies don’t always pay for them. Some options, like the Cefaly devices, have return policies, so you don’t have much to lose by trying them.
I think it’s a little difficult to know when to recommend neuromodulation, versus an oral medication for example, because there is a cost factor that has to be considered — and also it’s hard to predict efficacy. This is appealing to patients who maybe don’t want to take more medications, or have a lot of health issues that prevent them from taking medications. A lot of patients have medical comorbidities or contraindications that prevent the use of oral migraine medications. These devices open up a new migraine treatment for patients, like the elderly or pregnant women, for whom it was previously unavailable.
What do you envision for the future of neuromodulation?
Hopefully we will be able to make them more patient accessible by talking with insurance companies to bring down the cost. I think that will generate more interest in developing devices, too. The currently available migraine and cluster medications that we have are not great because they may present side effects, or aren’t easy to take. If you can come up with something that’s better tolerated, but just as effective, and that’s not technically a medication, I think there’s a lot of appeal for something like that.
Rashmi Halker, M.D., F.A.H.S is a member of the American Headache Society, a professional society for doctors and other healthcare workers who specialize in studying and treating headache and migraine. The Society’s objectives are to promote the exchange of information and ideas concerning the causes and treatments of headache and related painful disorders, and to share and advance the work of its members. Learn more about the American Headache Society’s work and find out how you can become a member today.