Two Diseases, Two Treatments, One Surgery

ReLACS iStent

Cataracts are the natural clouding of the eye lens; something some say will develop in everyone’s eyes by the age of 75. Cataracts cannot be reversed, only prevented. Surgery is the only treatment for cataracts.

Dr. John Berdahl says that what used to be the goal of cataract surgery was, “ok, let’s get that thing outta there!” Once artificial lenses were invented, Berdahl explains that surgeons then said, “Ok, let’s get that thing outta there and make it so your glasses aren’t Coke bottles, but you’ll still, for sure, need to wear glasses.”

Now, after many years of research and studies, advances in technology have gotten to the point where, a lot of the time, ophthalmologists can do cataract surgery and decrease patients’ use of glasses afterward. Much of this ease is thanks to something called Refractive Laser-Assisted Cataract Surgery or ReLACS (pronounced like “relax”)

Research 1


ReLACS, Refractive Laser Assisted Cataract Surgery, is a new LASER Cataract Surgery. Dr. John Berdahl explains ReLACS in this long yet interesting way: “We do that [cataract surgery] with a number of different technologies; one of them is a femtosecond laser that takes the most precise steps of cataract surgery, takes it out of my hands, and the laser does it. Now, my hands are good, but they just can’t compete with the precision that comes along with the laser. But there are a lot of other things that go into that.

There’s a tool that we use that measures the refraction of the eye after the cataract’s out so we can put the most properly powered lens into position and rotate it exactly into the right spot. There are special measurements that we take beforehand. If we’re close but we’re not quite there, we can do LASIK afterward and that’s all included in this package that we call ReLACS. And when we do that, we’re probably able to get people [to] accomplish their visual goals of not having to wear glasses, quite as much, for specific activities maybe 95% of the time or so.”

Glaukos Istent

What often goes along with cataract surgery, in order to reduce any effects of glaucoma, is something called a Glaukos Istent. It is the smallest device ever implanted in humans.

Dr. John Berdahl describes it as, “It is tiny. It fits into the ridge of a fingerprint. It’s about as tall as the “1” on the date of a penny. So, it’s tiny.” The device is placed into the drainage pathway on the inside of the eye. This way, all of the drainage stays internal to the eye but still lowers the pressure built up within it. This stent is a great advance because it’s much safer than the other big glaucoma surgeries. It is also a much more comfortable surgery, which makes the staff at Vance Thompson Vision happy to hear.

“Glaucoma is a big deal,” explains Dr. John Berdahl.  “It’s the second leading cause of blindness in the world and when the damage occurs, we can’t undo it.” This being said, the stent is a big advantage and could greatly help prevent blindness. 

iStent penny


In many cases you can actually combine the ReLACS with a Glaukos Istent implantation. This combination is possible because the stent doesn’t change refraction, the visual acuity outcomes of the eye, like other glaucoma surgeries. With the improvements of combining these surgeries, we can make a patient’s life a lot better because now they’re seeing clearer, they don’t have to wear glasses as much, and they don’t have to take as many glaucoma eye drops.

Dr. John Berdahl’s Involvement

Dr. John Berdahl has been involved with the clinical trials for the Glaukos Istent for the last five years. Since this device is an entirely new category of glaucoma surgery, Dr. John Berdahl has been able to be a part of the development since the beginning and has helped advise the Gaukos company, helped them educate surgeons and representatives about the Istent, and participated in the research that has gotten it to where it is today. Dr. John Berdahl has also been involved with the global development of the technology. He comments of this, saying, “I’ve actually gone overseas to do research with the Istent, I went to Armenia. We took care of folks that would otherwise not have access to any technology. We’re learning a lot from that and helping a lot of people with that.” 

Dr. John Berdahl continues to educate surgeons, help make developments to the Glaukos Istent, and improve eye care across the globe.