I’d like to share a case with you today. Ken was a 70 year old white male, he’s been a patient in my office for many years. His father was also a patient and his father had lost almost all of his central vision, the last eight years of his life, as a result of age-related macular degeneration in advanced geographic atrophy stage in both eyes. Ken’s biggest fear is losing vision like his father did.
Vitamin therapy for AMD patients
And it was in 2012 that I saw my first retinal finding which was fine drusen perimacular in his left eye. So I had the tough discussion with Ken that drusen were oftentimes a precursor to age-related macular degeneration and that we needed to intervene. And at the time intervention, because he was a nonsmoker, was mostly AREDS1 therapy combined with good UV protection and good blood vessel health control through his primary care doctor. In 2013 the results of AREDS2 became available and we switched him over to the AREDS2 formula vitamin therapy.
In 2014 when he returned, the drusen were gone. Disappearing drusen was a remarkable finding. As you can see in these sequential photos: the drusen being somewhat dense in the first image, less dense in the second image, and completely gone in the third image. It was a historic case in my office to see for the first time that actually drusen can disappear. And I think that’s a historic finding really around the country and around the globe. We have to understand that early intervention can make a difference and retinas can actually improve.
Dark adaptation and its role in detecting subclinical AMD
In 2014 the dark adaptation testing became available for me to use with our patients. And so at Ken’s next regular examination, I had him perform dark adaptation testing. In explaining to Ken about the test and how significant it was, he related to me a story about his father and he said I’ll never forget this story.
The story goes as follows: his father and mother were big RVers. In Pennsylvania, we have the Turnpike that goes through three mountains and so there are three long tunnels. On the way back from one of his RVing adventures, as his father was driving through the tunnel, he alerted his wife “You’ve got to take the wheel! You’ve got to take the wheel! I can’t see!” As he went from the light into the dark tunnel, he became clinically blind. So his wife drove through the tunnel and they made their way back home. Of course, at that time he had normal vision.
That story is so remarkable because I explained to Ken the dark adaptation and its relationship at predicting future AMD and central vision loss. It was an example of how at the time (and this was in the 1980s), there was no doctor that knew of that association. As he lost his vision going through the tunnel little, did anybody know that he would be at high risk, a 90% chance, of developing AMD. Which he unfortunately did in both eyes.
With the advent of the dark adaptation instrument, we know about that association. It has been well verified. And so Ken could further understand and better appreciate the dark adaptation test. As we tested his eyes, he went from an abnormal dark adaptation after years of AREDS2 vitamin therapy and maintaining good blood vessel health and good UV protection, he actually had improved dark adaptation.
AdaptDx is to AMD as what visual field is to glaucoma
It is quite remarkable that for all these years, we did not have a screening test to identify our patients that are at risk for AMD. And just as we’ve done tonometry for many years to identify those patients at risk for peripheral field loss from glaucoma, now we need to be screening our patients using the AdaptDx to identify those that will be at 90% risk of having future central vision loss. So routine screening for our patients 50 and over is the next new standard of care model that the AdaptDx will afford all doctors of optometry and ophthalmology performing primary care.