ERNIE BOWLING, OD, FAAO, FNAP is in practice in Rome, GA, and is past chair of the American Academy of Optometry’s Comprehensive Eye Care Section
Remember the ubiquitous nature of digital dry eye disease in your practice.
With the increased usage of digital devices in both adults and children, ODs should be actively searching for dry eye in their practices and screen all patients. ODs are able to do this with the tools already available to them.
The days when computer use was restricted to office work are long past. Modern computer use has extended to the classroom, home, and for most all activities. Excessive computer use has led to an increase in health-related problems in video display terminal (VDT) users, particularly in students and younger age groups. Foremost of concern for optometrists is digitally-related dry eye disease (DED).
I am sure ODs are seeing more dry eye in their offices, reaching veritable epidemic proportions, and the patients suffering from dry eye disease are growing ever younger. So let’s discuss dry eye in this cohort. Most of what you will read you have likely already seen. I want to emphasize the prevalence of dry eye and why all ODs should be actively searching for dry eye in their practices.
Rise of digital device use
Since the advent of the internet, there has been an almost viral expansion of accessibility to it. Consider the percentage of global population with internet access:1
16 percent in 2005
30 percent in 2010
51 percent in 2017
58.8 percent in 2019
More by Dr. Bowling: Hope in the time of COVID-19
Digital dry eye is directly tied to digital device use. Ninety percent of American adults report using digital devices greater than two hours a day.2 Sixty percent of Americans use digital devices for at least five hours a day.3 Some 71 percent of Americans use digital devices for over seven hours a day.4 Some 67 percent of people use three or more devices simultaneously.2 Some 27 percent of users report experiencing dry eye.3 Older subjects and people spending more than four hours a day on VDTs are at major risk for developing DED.5
ODs see the effects of digital use on our younger patients. Starting in infancy, children gravitate to the glowing screen in their parents’ hands; school-aged children are required to complete assignments online; and adults shop, socialize, and work using screens. Add in entertainment, and the hours people spend in front of a screen are staggering.
It is not a surprise that current research suggest that screen time may play a significant role in dry eye. Children are raised with digital devices. About 70 percent of adults report their children spend more than two hours a day on digital devices.2 Some 23 percent of children report playing on digital devices as their favorite activity.3 Teens spend more than eight hours per day on digital devices.6 Children age eight to 12 are getting six hours a day of screen time.6
Approximately 10 percent of youth report dry eye symptoms.3
A 2016 study found that children who spend more time on their smartphones have more dry eye symptoms.7 This same study also found outdoor activity appeared to be protective against pediatric dry eye disease.
Effects of device use
Research shows ocular pathophysiologic effects from digital device use.
Both book reading and computer use result in decreased blink rates and increases in partial blinks. ODs have known that reading reduces the normal blink rate, but digital device use reduces that blink rate even further.
Ocular dryness is often accompanied by alteration in conjunctival epithelial cell morphology and conjunctival goblet cell density.8 Digital device use reduces blink rate to five to six blinks per minute vs normal of 14 blinks per minute.9 Patients have higher incomplete blink rates when reading from digital devices (7 percent) vs. 4 percent when reading from hard copy.10 Blink rate, blink amplitude and tear film stability are compromised during VDT use.11 Visual fatigue is greater with LCD displays vs. e-ink and hard copy.12 Eye dryness is common after prolonged computer use with the prevalence ranging from 30 percent to 68.5 percent.13 Low mucin 5AC concentration in the tears with prolonged VT use.14 The oxidative stress marker hexanoyl lysine (HEL) was significantly increased at four hours of smartphone use than at baseline and at one hour of smartphone use.15
Contact lenses and devices
Contact lens wear is a risk factor for abnormal tear physiology, and contact lens wearers are 12 times more likely than emmetropes and five times more likely than spectacle wearers to report dryness symptoms.16
Add in computer use and the numbers increase even further. Some 83 percent of male and 87 percent of female contact lens wearers reported at least one dryness symptom compared to 68 percent of male and 73 percent of female non-contact lens wearers among computer users.17 And those dryness symptoms were more prominent among contact lens wearers using digital devices for three to six hours than among those using devices for less than three hours.17
Dry eye diagnosis
ODs understand the differences between the 2007 and 2017 DEWS definitions of dry eye.18 Hyperosmolarity is one common component of the two definitions. The etiophysiologic distinction between aqueous deficiency and evaporative dry eye is not included in the 2017 definition of dry eye, but inflammation is. The new definition reflects research showing an inflammatory component to dry eye disease, and tear film osmolarity and neurosensory abnormalities play significant roles.
Perhaps the most powerful part of the current definition is the reference to the loss of homeostasis of the tear film. Because the eye is so critical to survival, much of its function centers around maintaining or regaining the physiologic balance necessary for sustained stable vision, such as protecting and repairing the ocular surface from damage or disruption. When the delicate homeostatic balance of the ocular surface system is disturbed, it triggers an activation of a progressive stress response resulting in the production of pro-inflammatory cytokines and matrix metalloproteinases.19
Meibomian gland dysfunction (MGD) is recognized as both a cause and a contributor to dry eye.20 It is an obstructive and inflammatory disease resulting in insufficient and abnormal production of tear lipids. While most associate MGD with excessive tear evaporation, its role in tear dysfunction is far more complicated. Meibomian gland lipids have tear stabilizing functions beyond serving as an evaporative barrier.21
An unstable tear structure leads to surface exposure and, in more severe cases, frank damage. Maintaining integrity and function of the ocular surface is so critical that the eye is equipped with mechanisms such as increased mucin production to maintain and regain homeostasis.
Obstruction is the most recognized cause of MGD and resulting tear lipid insufficiency.22 As meibum stagnates and becomes saturated and thickened, pressure within the glands mounts and production is down-regulated. Gland clearance has long been recognized as a treatment for MGD.23 Performed appropriately, this includes the application of heat to help melt congealed meibum and mechanical expression.
Although DEWS II offers the most comprehensive view of dry eye to date, its complexity can be daunting for many clinicians, especially in diagnosing and managing the condition. So, let’s back up for a moment.
In 2006, a group met to discuss the state of dry eye disease. The results of their work was published in August 2006 and preceded the DEWS report.24 This group, often referred to as “The Delphi Panel” or the “Dysfunctional Tear Syndrome Study Group” was polled for its most commonly used tests for evaluating a patient with probable dry eye. Their top four: fluorescein staining, tear break-up time, Schirmer’s test, and rose bengal staining. These are tests any clinician can perform in her office and are part of any dry eye protocol.
Since 2006, there has been an explosion of dry eye testing. How have testing patterns changed over a decade later?
A 2017 study surveyed 101 ophthalmologists, including 43 corneal specialists, regarding dry eye diagnosis.25 Their top three most common ”traditional” dry eye tests performed and the percent of each test performed by the doctors:
Corneal fluorescein staining (8 percent)
Tear break-up time (78 percent)
Anesthetized schirmer’s test (51 percent)
Conjunctiva lissamine green and/or rose bengal staining (<25 percent)
The top three most common “newer” dry eye tests performed:
Tear osmolarity assessment (23 percent)
MMP-9 testing (17 percent)
LipiView (Johnson & Johnson Vision, 13 percent)
Note the same top four tests identified by the 2007 group were still the top four tests performed in 2017. This survey also added three “newer tests,” but the same tests are still being used a decade after the first TFOS report. Guess what? These top four tests and two of the newer tests can be incorporated into any practice, no matter the size, with a minimal investment.
But what about optometrists’ choice of diagnostic testing? A poll fielded on the Optometry Times® website26 asked ODs what objective test for dry eye they think is the most important. In first place-but not overwhelmingly so-was tear film break-up time with fluorescein as the most important objective dry eye test with 33 percent of respondents making this choice. After a sharp drop, corneal staining was second choice. Only 17 percent of respondents felt it was the most important objective test. Third and fourth place were close: 12 percent of ODs held tear osmolarity testing to be most important, and 11 percent voted for non-invasive tear break-up time. Conjunctival staining was fifth with 9 percent of respondents, and Schirmer was sixth with 7 percent. Meibography follows in seventh place with 5 percent. Tied for last as the most important objective dry eye test were MMP-9 and phenol red thread test with 1 percent of respondents. Compare the results of this small survey with how you diagnose dry eye in your practice.
Learn more: Contact lens wear still safe amid COVID-19
General treatment considerations in dry eye caused by digital devices include:
Avoid excess caffeine
Turn off overhead fans at night and consider a humidifier
Digital device specific recommendations include remembering to blink, the 20-20-20 rule, adjust device brightness, and consider changing background color from bright white to cool grey.
Most optometrists have heard of the 20-20-20 rule for preventing and relieving digital eye strain. The catchphrase suggests taking a 20 second break every 20 minutes by looking 20 feet away. Numerous sources now refer to it, including the American Optometric Association27 and the American Academy of Ophthalmology.28
Other treatment considerations in dry eye caused by digital devices include:2
Adjust the screen directly in front of the face below eye level. Do not tilt screen.
Check the distance from you to screen: Extend a hand; it should lie flat against the VDT. Lessen overhead and surrounding light. Increase font size on the device. Keep handheld devices at a safe distance and below eye level. Most children hold devices at 5 to 6 inches from face. Increase distance.
Blinking exercises can be beneficial, and the importance of reestablishing normal blink patterns must be reinforced. Dry eye expert Donald Korb, OD, FAAO, has long been a proponent of blink training, and it is an essential part of restoring function to the meibomian glands. I encourage patients to download a blinking app created by Dr. Korb. It is available for iOS for free in the App Store. Patients can set their own blinking reminders for their desired frequency.
The purpose of this article was simply to alert ODs to the ubiquitous nature of digital dry eye disease and therefore to encourage them to look for the disease in their patient population. ODs don’t need to spend thousands of dollars or go to weekend workshops to diagnose and treat dry eye. However, those are options available.
ODs have the tools in their offices and the knowledge to conduct a cursory dry eye evaluation. They just need to be doing them. Dry eye is optometry’s golden goose. Think about it: Skills and the tools necessary are already available. ODs don’t need to refer it for surgical considerations. And patients deserve help with this condition. Take a few moments to probe for dry eye. Your patients will thank you for it.
More by Dr. Bowling: Coronavirus: A quick summary for optometrists
1. Internet Growth Statistics. Available at: https://www.internetworldstats.com/emarketing.htm. Accessed 3/30/20.
2. The Vision Council. Digital Eye Strain. Available at: https://www.thevisioncouncil.org/content/digital-eye-strain. Accessed 3/30/20.
3. WebMD. Dry Eye and Screen Use. Available at: https://www.webmd.com/eye-health/dry-eye-screen-use#1. Accessed 3/30/20.
4. American Optometric Association. Kids’ prolonged smartphone use could trigger dry eye. Available at: https://www.aoa.org/news/clinical-eye-care/kids-prolonged-smartphone-use-could-trigger-dry-eye. Accessed 3/30/20.
5. Rossi GCM, Schudeller L, Bettio F, Pasinetti GM, Bianchi PE. Prevalence of dry eye in video display terminal users: a cross-sectional Caucasian study in Italy. Int Ophthalmol. 2019 Jun;39(6):1315-1322.
6. Stipes C. How to Protect Your Kids’ Eyes from Too Much Digital Device Use. Available at: https://www.uh.edu/news-events/stories/2017/June/06302017dryeye.php. Accessed 3/30/20.
7. Moon JH, Kim KW, Moon NJ. Smartphone use is a risk factor for pediatric dry eye disease according to region and age: a case control study. BMC Ophthalmol. 2016 Oct 28;16(1):188.
8. Bhargava R, Kumar P, Kaur A, Kumar M, Mishra A. The diagnostic value and accuracy of conjunctival impression cytology, dry eye symptomatology, and routine tear function tests in computer users. J Lab Physicians. 2014 Jul;6(2):102-8.
9. Freudenthaler N, Neuf H, Kadner G, Schlote T. Characteristics of spontaneous eyeblink activity during video display terminal use in healthy volunteers. Graefe’s Arch Clin Exp Ophthalmol. 2003 Nov;241(11):914-20.
10. Portello JK, Rosenfield M, Chu CA. Blink rate, incomplete blinks and computer vision syndrome. Optom Vis Sci. 2013 May;90(5):482-7.
11. Cardona G, Garcia C, Seres C, et al. Blink rate, blink amplitude, and tear film integrity during dynamic visual display terminal tasks. Curr Eye Res. 2011 Mar;36(3):190-7.
12. Benedetto S, Drai-Zerbib V, Pedrottu M, Tissier G, Baccino T. E-readers and visual fatigue. PLoS One. 2013 Dec 27;8(12):e83676.
13. Uchino M, Schaumberg DA, Dogru M, Uchino Y, Fukagawa K, Shimmura S, Satoh T, Takebayashi T, Tsubota K.. Prevalence of dry eye disease among Japanese visual display terminal users. Ophthalmology. 2008 Nov;115(11):1982-8.
14. Uchino Y, Uchino M, Yokoi N, Dogru M, Kawashima M, Okada N, Inaba T, Tamaki S, Komuro A, Sonomura Y, Kato H, ArgÃ¼eso P, Kinoshita S, Tsubota K. Alteration of tear mucin 5AC in office workers using video display terminals: The Osaka Study. JAMA Ophthalmology. 2014 Aug;132(8):985-92.
15. Choi JH, Li Y, Kim SH, et al .The influences of smartphone use on the status of the tear film and ocular surface. PLoS One. 2018 Oct 31;13(10):e0206541.
16. Nichols JJ, Ziegler C, Mitchell GL, Nichols KK. Self-reported dry eye disease across refractive modalities. Invest Ophthalmol Vis Sci. 2005 Jun;46(6):1911-4.
17. Gonzalez-Meijome JM, Parafit MA, Yebra-Pimentel E, Almeida JB. Symptoms in a population of contact lens and noncontact lens wearers under different environmental conditions. Optom Vis Sci. 2007 Apr;84(4):296-302.
18. Craig JP, Nichols KK, Akpek EK, Caffery B, Dua HS, Joo CK, Liu Z, Nelson JD, Nichols JJ, Tsubota K, Stapleton F. TFOS DEWS II Definition and Classification Report. Ocul Surf. 2017 Jul;15(3):276-283.
19. Stevenson W, Chauhan SK, Dana R. Arch Ophthalmol. 2012 Jan;130(1):90-100.
20. Lemp MA, Crews LA, Bron AJ, Foulks GN, Sullivan BD. Distribution of aqueous-deficient and evaporative dry eye in a clinic-based patient cohort: a retrospective study. Cornea. 2012 May;31(5):472-8.
21. Willcox MDP, ArgÃ¼eso P, Georgiev GA, Holopainen JM, Laurie GW, Millar TJ, Papas EB, Rolland JP, Schmidt TA, Stahl U, Suarez T, Subbaraman LN, UÃ§akhan OÃ, Jones L. TFOS DEWS II Tear Film Report. Ocul Surf. 2017 Jul;15(3):366-403.
22. Jester JV, Parfitt GJ, Brown DJ. Meibomian gland dysfunction: hyperkeratinization or atrophy? BMC Ophthalmol. 2015 Dec 17;15 Suppl 1:156.
23. Thode AR, Latkany RA. Current and Emerging Therapeutic Strategies for the Treatment of Meibomian Gland Dysfunction (MGD). Drugs. 2015 Jul;75(11):1177-85.
24. Behrens A, Doyle JJ, Stern L, Chuck RS, McDonnell PJ, Azar DT, Dua HS, Hom M, Karpecki PM, Laibson PR, Lemp MA, Meisler DM, Del Castillo JM, O’Brien TP, Pflugfelder SC, Rolando M, Schein OD, Seitz B, Tseng SC, van Setten G, Wilson SE, Yiu SC; Dysfunctional tear syndrome study group. Dysfunctional Tear Syndrome: A Delphi approach to treatment recommendations. Cornea. 2006 Sep;25(8):900-7.
25. Fernandez K, Ying G-S, Massaro-Giordano G, et al. A Survey of Dry Eye Practice Patterns. IOVS. 2017 June;58(7):2651.
26. Bailey G. The most important objective dry eye test is TBUT with fluorescein, ODs say. Available at: https://www.optometrytimes.com/dry-eye-awareness/most-important-objective-dry-eye-test-tbut-fluorescein-ods-say. Accessed 3/30/20.
27. American Optometric Association. 20/20/20 To Prevent Digital Eye Strain. Available at: https://www.aoa.org/documents/infographics/SYVM2016Infographics.pdf. Accessed 3/30/20.
28. Boyd K. Computers, Digital Devices, and Eye Strain. American Academy of Ophthalmology. Available at: https://www.aao.org/eye-health/tips-prevention/computer-usage. Accessed 3/30/20.