When the topic of glaucoma comes up, we often start discussing eye pressure and ignore vision and quality of life. I believe that pressure is the battle in glaucoma but vision and quality of life is the war. I am a refractive surgeon and dry eye specialist spending most of my day concentrating on the ocular surface. I know that if a patient has a poor ocular surface that I could perform an incredible surgery, but I will not achieve my ultimate goal, which is having the patient see better without the use of glasses and contact lenses. In my glaucoma patients, my goal is to lower the pressure but to also have my patients seeing better.

Over the years, I have developed a big glaucoma practice, and I often deal with a compromised ocular surface in these patients. Most of these patients are already at risk for a poor ocular surface because of advanced age. When you throw in glaucoma drops that are harsh on the cornea as well, then you have patients who aren’t seeing well because of a poor ocular surface.

Reduce Drops by Adding Laser

What I have been trying to accomplish in my clinic is improved vision in the glaucoma patient because I know that I can improve their quality of life no matter the damage to their nerves. Even if a patient has a cupped-out nerve, if their ocular surface is terrible, they are going to experience pain that will make their quality of life worse. One way that we have improved the ocular surface in these patients is by reducing or eliminating drops with laser surgery. For several years, we have been successfully utilizing selective laser trabeculoplasty (SLT) and micropulse laser trabeculoplasty (MLT) to decrease the dependence on drops. But sometimes SLT and MLT cannot lower the intraocular pressure enough to eliminate drops.

Two years ago, my wife and business partner, Melissa Toyos, MD, and I began utilizing the Iridex Cyclo G6 MicroPulse P3 laser system. The technology utilizes an infrared laser, 810 nm wavelength, and pulses that energy level (0.5 ms laser application followed by a 1.1 ms rest) so that you do little harm to tissue and achieve a desired biologic effect. We published a paper on our experience, in which we demonstrated that patients, on average, had an eye pressure drop of 30% at 6 months to 1 year post treatment.¹ Patients dropped from a baseline of 3.3 topical glaucoma medications with an average IOP of 25.6 mmHg to a mean of 1.8 topical medications with a mean IOP of 18.0 mm Hg at the final postop visit 6-12 months after the procedure. We achieved this lowering of pressure without any significant adverse events. Laser settings were a power of 2000 mw, total treatment time of 160 seconds (80 seconds per hemisphere x 2) and standard duty cycle of 31.3%. The procedure is an in-office procedure that does not require incisional surgery to the eye. The down time is minimal and it is cost effective when we look at the cost savings to the patient and the health care system.

We are now utilizing micropulse more frequently on a wider range of glaucoma patients with mild to severe disease. The laser procedure helped reduce IOP and the number of drops subsequently improving the ocular surface. Patients are reporting improved quality of vision and fewer symptoms normally associated with dry eye disease, like grittiness, dryness, scratchiness, and pain.

Cost Containment

Another topic that ophthalmologists rarely discuss but should be addressed is the cost of drops vs the cost of laser treatments. Because the United States spends 18% of its gross domestic product (GDP) on health care, one way that policy makers have thought to decrease debt is to lower the cost curve in health care. Other comparable countries spend about half of the relative GDP that the United States does. A Canadian study showed a reduction of half the amount of cost of care with SLT vs drops. If we can perform a laser treatment and eliminate 1 drop for 3 years that would be a cost savings of at least $1,500 per patient. Considering there are several million patients with glaucoma, this could be significant savings. Many countries, including the United Kingdom, are studying the use of laser vs medication for the treatment of glaucoma.

I believe that the MP3 will be a valuable tool in the treatment of glaucoma because it is a noninvasive treatment that can be done in the office. In our initial study, patients were given a peribulbar block to maximize comfort. We are currently studying the use of only topical drops for anesthesia, and initial results are promising. MP3 is different than a cyclodestructive procedure making the treatment repeatable. It is giving patients a greater percentage drop in pressure than other laser glaucoma procedures with very few adverse events. Over the last year, the only significant adverse event that we have seen is subconjunctival hemorrhages, but even that has been reduced with changes to our technique.

Summary

Considering the drawbacks of topical glaucoma medications, it becomes obvious that a noninvasive procedure that can eliminate drops would be the ultimate goal. We are scratching the surface of the potential of the MLT. If our success continues, then micropulse laser could be the first-line treatment that not only lowers pressure but maintains the quality of vision and activities of daily life. GP

References

1. Toyos M, Toyos R. Clinical outcomes of micropulsed transcleral cyclophotocoagulation in moderate severe glaucoma. J Clin Experimental Ophthalmol. 2016;7:6.

Rolando Toyos, MD, is the medical director and founder of Toyos Clinic in Germantown, Tennessee. Dr. Toyos reports speaker’s fees from Iridex and consultancy to Lumenis, Zeiss, and Shire. Reach Dr. Toyos at rostar80@gmail.com.