New Sleep Apnea Treatment: Hypoglossal Nerve Stimulation

November 12, 2009

Here’s a radically new approach to treating obstructive sleep apnea: hypoglossal nerve stimulation. I read about initial successful pilot studies many years ago out of Johns Hopkins, but thought the concept never took off since I didn’t hear anything more. I was wrong. ImThera recently announced their aura6000 Targeted Hypoglossal Neurostimulation (THN) device for obstructive sleep apnea at the Annual Meeting of the American Academy of Otolaryngology – Head & Neck Surgery in San Diego last month. There are two other companies rushing to come out with similar products. Apnex is one company and Inspire is another.

It turns out that this company’s been busy developing this product and is about to undergo clinical trials in Europe before trying it out here the US. The technology’s not new—it’s basically a nerve stimulation device that’s been used on other areas of the body before. In this case, activation of the rib cage muscles causes the device to stimulate the hypoglossal nerve, which tenses the genioglossus muscle of the tongue.

During non-REM deep sleep, all the muscles in the body relax partially, whereas in REM sleep, all the muscles are relaxed completely. In sleep apnea patients, this partial and total muscle relaxation leads to repeated obstructions and arousals. By sensing that the ribs are moving, it stimulates the tongue muscle, preventing eventual collapse of the throat tissues.

In the original Johns Hopkins article from 2001, eight patients underwent this procedures on one side of the tongue, and the AHI dropped from 52.0 to 22.6 in non REM sleep and 48.2 to 16.6 in REM sleep. The final results aren’t great, but significantly improved. Additional procedures may need to be performed, since the tongue isn’t the only area of obstruction.

If this procedure became available in the US, would you consider undergoing this procedure? Please enter your answers below in the comments box.

Written by Steven Park · Filed Under Blog
Tagged: ,genioglossus, hypoglossal nerve stimulation, sleep apnea

5 Responses to “New Sleep Apnea Treatment: Hypoglossal Nerve Stimulation”

Sara on November 13th, 2009 6:53 am

Just to clarify…the nerve stimulation treatment would be an ongoing lifelong intervention (similar to the use of CPAP)?
Victor H. on November 13th, 2009 8:04 am

I would not consider the procedure because the results are poor. Maybe the procedure would lower my AHI to 20.0. I know from my own experience that life is miserable with an AHI of 20.0 and your health is being slowly destroyed.

My AHI is 57.0 without CPAP and around 1.0 with CPAP. If I have problems with CPAP and my AHI moves up to anything above 3.0 or so, I feel very tired and sleepy the entire day. It makes sense if you consider that an AHI of 3.0 over seven hours of sleeping, means 21 awakenings and maybe 21 oxygen desaturations plus unhealthy increases in cortisol and adrenaline.

I was first excited when these devices were announced, but now I am skeptical that they will ever be very effective.
Dr. Steven Y. Park on November 14th, 2009 4:33 am

Victor,

You’re right. By itself, it won’t “cure” your sleep apnea, unless it’s performed in combination with procedures that address other areas of obstruction.
Ann Emerson on February 8th, 2010 9:36 pm

Just wondered whether the AHI was lowered without lowering the totalnumber of arousals from sleep? That is, did the stimulation of the hypoglossal nerve disrupt the patients sleep in and of itself? I think it's important to lower the AHI, obviously. But if a treatment creates arousals of a different type, then the patients' sleep won't be any more restful. Any idea whether this data is available Dr. Park? Thanks for sharing this research.
Steven Park on February 9th, 2010 4:21 am

Ann, that's great question. I don't remember from the paper if arousals were mentioned, but subjective results were generally positive. Any device, whether a nerve stimulator, oral appliance or CPAP, will cause increased arousals. These are questions that will be answered more fully in the initial upcoming clinical trials.