What is “Neurostimulation” for dry eye treatment and do I need it?
To a large degree, everything about our body is regulated by nerves, so stimulating the right nerves, in the right sequence and pattern is the key to “living well.” Since tears are a vital part of looking, seeing and feeling better (our eyeThera motto), it stands to reason that controlling how and what kind of tears we make is key to our eye’s health.
Many times, patients ask me, “does that mean I should cry more?” Unfortunately, the reflex tearing we do when we visibly “cry,” is the product of our “fire hose,” so this is primarily a salt-water tear – and better for washing a loose lash out of our eye, than it is at nourishing. lubricating and supporting the surface. The “sprinkler system” tears are the “good stuff” with water, salt, protein and oil to take best care of our eyes. Fortunately, we have a nerve inside of our nose that connects to the entire sprinkler system and when activated properly, it can stimulate these cells and glands into doing what we need of them to make more and better tears – assuming that the cells and glands are up to it!
I use the analogy of a “buggy whip” when stimulating the sprinkler system, that - when active - will give a slight “snap of the whip” to those harnessed cells and glands (what eye doctors refer to as the “lacrimal functional unit” – or LFU to those in the know). If the “horses” (or LFU) are able, then they can “giddie up and gallop” for you – but if they are 3-legged lame, then they will only limp along (and if dead – then it can be like whipping a dead horse).
The original idea of applying this theory to dry eye came from a biotech engineer. In speaking with him at an eye conference where my eyeThera partners and I had the opportunity to meet, he explained that he was literally “sitting on the dock of a bay” (in San Francisco), preparing to eat a fish taco, when he sniffed it and inadvertently sniffed some of the taco pepper into his nose. This led to a bout of sneezing and then tearing. As an engineer, he spent a lot of time staring at computer screens and was aware he had dry eye disease – so having a bout of healthy tears flood his eyes was a welcome relief that left a lasting impression. Time spent with some eye doctors and other engineers led to his development of a tool originally dubbed “Oculeve” but later (when bought by the eye industry giant - Allergan (maker of Restasis) - for what could have been up to $1 Billion dollars, it was renamed “True Tear.”
True Tear used a gel-coated electrical activator to deliver a small electrical “shock” to the spot inside your nose where the nerve exists, which will buggy whip the LFU. It allowed for varying degrees of “shock” – from negligible to forceful. Some of you reading this may have used True Tear – and if you did, then you know what I’m talking about. Unfortunately, the cost was prohibitive, in part due to the acquisition cost of the base unit, in part due to the ongoing cost of the applicator tips - and the fact that insurance companies didn’t want to pay for it. Also unfortunate, is that the response to the stimulator was variable – some found it worked great (with good horses) and some found it didn’t work at all (with very lame or dead horses). A single trial was often not enough to judge how well it would work – so an in-office demo was not a reliable indicator and a bunch of units were sold to patients who didn’t get much out of the device. Side effects could be discomfort and sneezing (like that taco pepper) and it needed to be reapplied throughout the day to get the full day’s tear response. Lastly, not all doctors wanted to buy a stock of units that might sit on the shelf or soon be returned by disgruntled patients – and this led to a commercial “flop” of what was otherwise good technology. Allergan stopped production and this could have been a final chapter to neurostimulation for dry eyes.
Fortunately, the same engineer spawned another company (Oyster Point) with another neurostimulator product named Tyrvaya. Using the knowledge that certain contact-chemicals (like pepper) could stimulate the necessary tear-producing nerve, he and some chemical engineers came up with another use of a common nicotine-blocking agent (marketed as Chantix) previously used to help people quit smoking. This binds to – and stimulates – the LFU nerve like the electrical “buggy whip,” but without the shock. A small dose, sprayed directly to the inside of the nose (in the area where eyeglass-frames would rest) does the trick. It also commonly causes sneezing, though most will adapt to the point where sneezing is minimal. Twice a day suffices for most – but again – only if the LFU can make a tear.
Better news is that many insurance companies are now beginning to cover some – or most – of the cost – so it can be more affordable. It is easy to use once you get the knack of it (and your prescribing doctor can give more detailed instructions if you are considered a candidate). The company has made efforts to supply samples to a large number of dry eye clinics and dry eye specialists – so there is a good chance that your US-based doctor can get you a 2-week trial for free.
For those with aversions to spraying chemicals up their nose, there is also a stimulator called the iTear, that stimulates the same nerve – but on the track it takes outside of the nose. This electrical device sends a vibrational stimulus through the skin around the same area of the nose as the spray (and also where the True Tear applicators would be aimed) – but from the outside (rather than inside) of the nose. It is supplied as a small, compact device that is prescribed (and often sold) by your dry eye doctor. You get an initial “fill” of the prescription when you register the device and then can get ongoing “refills” online through the doctor’s prescription.
It suffers the same fate as every other “buggy whip” if the LFU horses are “lame” – but with ongoing use and with supportive treatments (like the “homework” I promote, often in concert with the off-label RF heated “unplugging” of the oil glands and IPL treatments to reduce inflammation and to stimulate the glands), I find that many can benefit from these “Neurostimulation” treatments. As always, it is important to work in concert with your dry eye specialist and primary care doctors to make sure these treatments are right for you.