By Tammy Tully, OD
Oct. 24, 2018
With the aging population has come an increased prevalence of age-related macular degeneration (AMD). As many as 11 million people in the U.S. have some form of AMD, and this number is expected to double to nearly 22 million by 2050. Furthermore, the number of people living with macular degeneration is expected to reach 196 million worldwide by 2020, and increase to 288 million by 2040, according to the BrightFocus Foundation.
The momentum this disease is gaining requires a proactive approach by eyecare providers that targets earlier diagnosis and active disease management. Fortunately, there is a newer technology—the AdaptDx dark adaptometer from MacuLogix—that does just that.
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Since adding the AdaptDx to my practice last year, I now have a functional test for AMD that complements my clinical exam and imaging, much like a visual field does for glaucoma. This allows me to diagnose AMD at its earliest stages with greater confidence. Once diagnosed, I can educate my AMD patients about appropriate follow-up care visits and what they can do to slow the progression of the disease to preserve their vision longer.
Patients are grateful for the early diagnosis of a sight-threatening disease, becoming more loyal to our practice and more compliant with my treatment plan. As a doctor, I can feel confident that I am providing the best care possible, while growing my practice and profitability in the process.
Measure Time of Dark Adaptation
As the only commercially available automated dark adaptometer, the AdaptDx measures a patient’s Rod Intercept (RI). RI is the number of minutes it takes for the eye to adapt from bright light to darkness at a standard stimulus level.
This is valuable clinical information because studies have shown that impaired dark adaptation is evident at least three years before drusen are visible – allowing us to identify subclinical AMD or confirm our suspicion of AMD. The RI is an automated output that requires no interpretation, providing me with a clear and objective measurement of retinal function with 90 percent sensitivity and specificity to the presence of AMD.
• An RI time less than 6.5 minutes indicates normal dark adaptation consistent with healthy photoreceptor function.
• An RI time greater than 6.5 minutes indicates impaired dark adaptation, most often due to AMD in patients over 50.
The Rapid Test protocol takes less than 6.5 minutes, providing a pass/fail outcome. Those who fail (timing out at 6.5 minutes) return for the Extended Test protocol to determine the severity of their dark adaptation impairment.
I continue to test my AMD patients every three to six months with the Extended Test to monitor disease progression. Both protocols are conducted by our technicians, who were easily trained in less than a day to use the technology. My practice partner and I review the test outcomes, and then discuss the results with the patient. If they have AMD, we partner with them to proactively manage their disease.
Who Gets the Test?
Not all patients in my practice get the AdaptDx test. I would need reason to order it, such as documented soft drusen, or the patient reporting that they are having trouble seeing at night. Night vision complaints are fairly common in our patients over 50, and now we have a test to determine if the complaint could be an early symptom of AMD.
The way I frame the test for patients is as a preventative health evaluation: “We have a simple test I would like to have you take that will tell us how long it takes your eyes to adapt to the dark. It will give us a score that will tell us if you have macular degeneration, even in its earliest stages. That way, if we detect signs of disease, we can help prevent the disease from progressing. There are nutritional supplements, changes to your diet and lifestyle, and measures to protect against sun and blue-light damage, that could help preserve your vision. So, this is helpful information for us to have.”
The patient typically is appreciative of the ability of our practice to provide this kind of early detection, and readily agrees to the test. In a majority of cases, the test is reimbursable due to previously documented drusen or a night blindness complaint.
Educate About the Test and the Results
We breakdown the reason we would like them to take the test into layman’s terms and this is often due to their chief complaint of difficulty seeing at night, or a clinical finding of drusen, for example.
We also explain how we are able to not only look at the structure of their retina with devices like OCTs and other retinal imaging, but we are able to test their retinal function with the AdaptDx as well. I will sometimes compare this to looking at both the hardware and software of your computer to diagnose the underlying issue. As a result, our patients are grateful for the additional testing, and ready to take action if disease is detected.
If a patient fails the AdaptDx, I might tell them: “The test you took indicates that your time to dark adapt is slower than it should be. It’s lucky that we now have this information because when it comes to macular degeneration, the sooner the better in taking preventative measures.
For instance, quitting smoking can reduce your risk of developing this disease, as can a diet high in green leafy vegetables and protecting your eyes from the sun and harmful blue light from electronic devices. Fortunately, we can help you with all of this. There is a nutritionist we know who can help you improve your diet, resources in our community to help you quit smoking and nutraceuticals we offer in our office that also may help.
I’m so glad we have this information, and can better protect your eyes! We will also send a summary of your exam today to your primary care physician to make sure they are controlling your cholesterol levels, monitoring your cardio-vascular system as well as your Body Mass Index or BMI. Together, we will come up with an AMD care plan and will see you for your next appointment in three, six, or 12 months, depending upon what we deem appropriate for your eye health.”
Practice and Profitability Builder
We saw a profit from our investment within the first month of using the AdaptDx. In our area, insurance reimburses approximately $58 [the national average is $64.08] for both the rapid and extended dark adaption tests (CPT 92284). If you only run two or three tests a week, you break even on the testing alone; if you run one test a day, you make a profit. Because we leased our AdaptDx, we have a monthly payment of less than $700. By performing at least one test per day, and typically more, we are able to not only easily cover our monthly payment, but improve our gross clinical revenue as well.
Additional testing to check for structural changes to the retina, such as OCT or fundus imaging, can be co-billed during the same office visit. In addition, we feel we enhance both patient care and practice profitability by recommending nutraceuticals, blue light blocking lenses and UV protection to patients with AMD. Ultimately, patients become much more motivated and compliant when we can provide a definitive diagnosis.
Diagnosing patients with AMD who we may have otherwise missed has allowed us to follow them more carefully and deepen the doctor-patient bond. This is just like following a patient who either has glaucoma or is a glaucoma suspect. Since AMD is three times more prevalent than glaucoma, you should expect to be running the AdaptDx more often than your visual field test.
Give Patients the Care They Deserve
The ability of the AdaptDx to help me diagnose AMD is a huge advantage for our patients and practice. We don’t have to wait for significant vision loss, or structural changes to the retina to occur to detect AMD.
We can catch the disease in its very earliest stages, helping our patients be proactive and better manage their health.
MacuLogix provided us with extensive in-practice training for our entire staff and continues to help us optimize our workflow. This set us up from the beginning to create a better environment in which to care for the patient, and allows us to give our patients the care they deserve.