Safety and patients’ satisfaction of transcutaneous supraorbital neurostimulation (tSNS) with the Cefaly® device in headache treatment: a survey of 2,313 headache sufferers in the general population. J Headache Pain. 2013 Dec 1;14:95. doi: 10.1186/1129-2377-14-95. Magis D, Sava S, d’Elia TS, Baschi R, Schoenen J.
Transcutaneous supraorbital nerve stimulation (tSNS) with the Cefaly® device was recently found superior to sham stimulation for episodic migraine prevention in a randomized trial. Its safety and efficiency in larger cohorts of headache sufferers in the general population remain to be determined.The objective of this study was to assess the satisfaction with the Cefaly® device in 2,313 headache sufferers who rented the device for a 40-day trial period via Internet.
Only subjects using specific anti-migraine drugs, and thus most likely suffering from migraine, were included in the survey. Adverse events (AEs) and willingness to continue tSNS were monitored via phone interviews after the trial period. A built-in software allowed monitoring the total duration of use and hence compliance in subjects who returned the device to the manufacturer after the trial period.
After a testing period of 58.2 days on average, 46.6% of the 2,313 renters were not satisfied and returned the device, but the compliance check showed that they used it only for 48.6% of the recommended time. The remaining 54.4% of subjects were satisfied with the tSNS treatment and willing to purchase the device. Ninety-nine subjects out of the 2,313 (4.3%) reported one or more AEs, but none of them was serious. The most frequent AEs were local pain/intolerance to paresthesia (47 subjects, i.e. 2.03%), arousal changes (mostly sleepiness/fatigue, sometimes insomnia, 19 subjects, i.e. 0.82%), headache after the stimulation (12 subjects, i.e. 0.52%). A transient local skin allergy was seen in 2 subjects, i.e. 0.09%.
This survey of 2,313 headache sufferers in the general population confirms that tSNS with is a safe and well-tolerated treatment for migraine headaches that provides satisfaction to a majority of patients who tested it for 40 days. Only 4.3% of subjects reported AEs, all of them were minor and fully reversible.
What I like was they demonstrated the safety of non-invasive supraorbital (forehead above the eyes) electric stimulation for headaches and found minimal, mild, and no serious side effects on 2313 patients. That is by far the largest population I have seen tested with any form of electric stimulation. They gave reasonably clear parameters with regards to TENS protocol used: a biphasic rectangular waveform, pulse duration of 250 uS, 60 Hz, and maximum intensity of 16 mA to be used 20 minutes per day, daily. Initially I thought those parameters sounded weak, but when programming my own electric stimulation machines (both my Genesy 1100 and EV-906) to the same parameters , 16 mA turns to be pretty strong when electrodes are placed over the forehead. I’m very electric stimulation tolerant and was able to get to 16 mA without much trouble, but it felt intense. My office staff, all of which are female and some of which get headaches, were only able to tolerate 5-7 mA before being limited by pain/discomfort. So, I don’t think weakness of the machine is a problem in the study. I think supraorbital and supratrochlear nerves being very close to the skin surface are relatively easy to reach with TENS and thus don’t need an especially powerful stimulator.
They didn’t give any data with regards to how well the machine worked except that 54.4% said they were happy enough to purchase it at $246 Euros over the rental costs during the study (full price was 295 Euros). However, there was no data given with regards to headache intensity, frequency, or disability over the course of the study. I would think that kind of data would be easy to gather with a survey, and though there was no control group it would be interesting to see if and how much the changes were from pre- to post-treatment for such a large number of people. To be fair, the same group of authors did give such data in another study, on a much smaller number of subjects. I intend to review that next, but it would have been good to see some additional outcome data on this larger group.
Criticisms aside, I like the study. It gives great safety information and got FDA approval on some specific TENS outputs and pad placements that I can incorporate into my own electric stimulation treatments and research. I do suspect that outcomes could be improved by incorporating suboccipital (back of the neck) stimulation with the supraorbital stimulation. That is proving to be the most effective for chronic migraines headaches in the peripheral nerve stimulation studies, which I am currently gathering data on.
As always, if you have any further questions or need for clarifications, please don’t hesitate to ask. Being aware that some of my blog ideas are contentious and occasionally a bit out of the field of my expertise, I encourage my readers to come forth with any questions/comments that are of interest or concern. Your comments are valued and welcomed.
Chad Reilly is a licensed physical therapist, located in North Phoenix, practicing science based medicine with treatment protocols unique and effective enough to proudly serve patients from Phoenix, Scottsdale, Mesa, Chandler, Tempe, Peoria, and Glendale.