Digital vision syndrome: Building a comprehensive care model
The symptoms of DVS include uncorrected refractive errors, dysfunctional tear syndromes and undiagnosed ocular misalignments.
It is fair to say that there is nothing other than smoking that has a greater deleterious effect on the health and function of your eyes than the use of a computer. Where once I used to ask my patients what they did for a living, I now simply say: “How do you use computers in your day-to-day life?” When thinking about computer use, we must be mindful that what we are actually talking about, at least insofar as eye care is concerned, is the use of computer screens. There is something about how information is presented on our computer screens by the most common programs and websites that causes discomfort and often enough real disease. This applies whether you are talking about a traditional desktop computer, a laptop, a tablet or the ubiquitous hand-held computer otherwise known as a smartphone.
Our multi-screen lifestyle is a direct cause of discomfort and dysfunction. Screen time of any type at any age can cause the triple threat of digital vision syndrome (DVS) symptoms: eye pain, headache and blurred vision. These can be seen in literally any age group. Remember, a Korean study found that 9% of elementary school students in grades 1 to 6 had classic dry eye disease. Indeed, in those so afflicted, there is a straight-line correlation between symptoms and screen time at least at the outset of DVS. Identifying the discreet underlying causes of these symptoms will lead to a coherent, comprehensive approach to treating this entity.
Your patients are not going to stop using their computers or their Kindles or their iPhones, so you are going to have to figure out how to help them. There are three areas in which abnormalities can cause our patients to experience the symptoms of DVS: uncorrected refractive errors, dysfunctional tear syndromes and undiagnosed ocular misalignments. The latter two cause symptoms both directly as well as through trigeminal dysfunction, leading to the central processing abnormality known as allodynia. Let us take these one at a time.
Sometimes the simplest solution is the one most often overlooked. How many times have you seen a patient having a problem for a second (or third or fourth) opinion and discovered that you were the first person to refract them? Latent hyperopia is an incredibly common cause of DVS. You can cure these patients for $10 at CVS! Seriously, though, this one is a layup. You can solve quite a few problems by uncovering hyperopia, high degrees of astigmatism and anisometropia and correcting them with spectacles. I know it sounds basic, but sometimes the simple solution is all it takes.
Presbyopia is an obvious next target for your inquiry. The physical effort needed to accommodate over the course of a day leads to symptoms of fatigue. Emmetropic patients in their 40s and 50s have lost the ability to accommodate, and they need help. Be careful when prescribing bifocals, especially progressive lenses. A majority of progressive bifocals have a small area in the blend zone dedicated to intermediate or computer distance. It often makes sense to prescribe an “office Rx” with the larger top of the lens set for computer working distance and then blending down to a near point for reading.
This is a dry eye column, so it stands to reason that DED is a part of the DVS story. Any near task causes us to blink less frequently. Through insights gained in part by looking at LipiView (Johnson & Johnson Vision) recordings of blink quality, we now know that looking at a computer screen causes us to blink less completely. This combination, with or without any true meibomian gland disease, will cause a type of evaporative DED. On your exam you will likely see a rapid tear breakup time, with or without inflammation. Once you have identified this, your job is straightforward: treat the DED you have found.
How you go about this will likely be driven by how evolved your DED protocols are. Do not forget the easy things. Teach your patient to blink better and more frequently. Prescribe an oil-based artificial tear (we are impressed by Refresh Optive Mega-3 from Allergan and Retaine MGD from Ocusoft), and go ahead and put them on re-esterified fish oil. Yes, I will address the whole DREAM study in an upcoming column; for now, just do it. Any inflammation (superficial punctate keratitis, positive MMP-9, etc) should be treated as a matter of course with (for now) Restasis (cyclosporine ophthalmic emulsion 0.05%, Allergan), Cequa (cyclosporine ophthalmic solution 0.09%, Sun Pharma) or Xiidra (lifitegrast ophthalmic solution 5%, Shire). If the symptoms outstrip the signs, be alert for so-called neurogenic pain and consider prescribing TrueTear (Allergan).
Micro-misalignment between the two eyes is the last of the three underlying causes of DVS. These misalignments create the same type of “always on” flow along the afferent pathways of the trigeminal nerve that causes neurogenic pain in DED, albeit from a different sensory source. For this knowledge, we can thank Vance Thompson and Michael Colvard and their extraordinary white paper on computer vision syndrome (as well as a companion paper on chronic headache). The science is just as elegant (and complex) as what we have learned from Dr. Digre, but I will give it my best.
Saccadic eye movements provide extremely quick readjustments of eye position. The primary function of these rapid movements is image acquisition, moving targets of interest from the periphery to the area of central vision. Smooth pursuit eye movements then take over, stabilizing images and allowing for deeper cortical visual processing. Small imbalances between peripheral and central image tracking create constant stimulation of the trigeminal nerve as proprioceptive fibers in the extraocular muscles continuously fire in an effort to realign the eyes. Sounds familiar, right?
This “always on” flow across the trigeminal nerve creates the same allodynia, or central pain processing abnormality, that we talked about in neurogenic eye pain and migraine. Misalignment between peripheral and central fusion is more pronounced in circumstances with higher levels of background illumination. Hello! No wonder our patients get headaches when they use a computer, tablet or smartphone.
In order to make use of this really cool visual science, it is necessary to be able to accurately measure these misalignments. Have you ever seen an amblyoscope? No? No worries, there are only about six of these monstrous (6 feet long!) instruments left. They were used back in the Dark Ages to precisely measure phorias and tropias, and they cannot measure the peripheral-central mismatches. For that you need the brilliance of neurolens and the SightSync. This ingenious device (created with help from Drs. Thompson and Colvard) provides both a peripheral and central alignment measurement in less than 3 minutes.
Then what? It turns out that the neurolens wonks have cracked one of optical science’s holy grails. Once you know the base deviation and the peripheral-central misalignment, you can now treat it with spectacles that incorporate a progressive prism — a holy grail! Branded “neurolens,” spectacles using this technology can be made in single vision or progressives to be worn while working on screens of all types. Guess what? The darned things work! DVS (and several other types of chronic headache) in appropriately chosen patients is dramatically relieved with the use of a progressive prism.
Digital vision syndrome can be seen in anyone who looks at a screen. Treat it by correcting basic refractive errors, treating dry eye and, if you can, diagnosing and correcting misalignment between peripheral and central fusion with neurolens.
Editor's note: This article has been updated to change the name of eyeBrain Medical to neurolens and to change the word Neurolens to neurolens.
- For more information:
- Darrell E. White, MD, can be reached at SkyVision Centers, 2237 Crocker Road, Suite 100, Westlake, OH 44145; email: email@example.com.
Disclosure: White reports he is a consultant to Allergan, Shire, Sun, Kala, Ocular Science, Rendia, TearLab, Eyevance and Omeros; is a speaker for Shire, Allergan, Omeros and Sun; and has an ownership interest in Ocular Science and Eyevance.