WebMD (12/22, Hendrick) reported that, according to a review published in the Dec. issue of the Journal of Food Science, “green leafy vegetables and colored fruits may affect visual performance and may prevent age-related eye diseases.” Such “foods contain the carotenoids…lutein and zeaxanthin, which play an important role in vision and have a positive impact on the retina,” researchers at the University of Georgia explained. Notably, “of about 20 carotenoids found in human blood, only lutein and zeaxanthin are found in the visual system, the researchers” wrote, “suggesting these pigments play a ’special role’ in human vision.”

Medscape (12/22, Barclay) reported that, according to a study published in the Dec. issue of the Archives of Ophthalmology, “intravitreal use of the corticosteroid triamcinolone may slow the progression of diabetic retinopathy, but adverse effects including cataract formation and glaucoma may prevent use of this treatment merely to reduce progression of proliferative diabetic retinopathy.” Two years after treating a “total of 840 eyes from 693 participants with diabetic macular edema” who were randomized “to receive laser therapy (n = 330), 1 mg of triamcinolone acetonide (n = 256), or 4 mg of triamcinolone acetonide (n = 254),” researchers found that “the cumulative probability of progression of retinopathy was 31% in the laser group, 29% in the 1-mg group, and 21% in the 4-mg group.”

BBC News (12/22) reported that a UK man, Russell Turnbull, who “lost the sight in one eye in 1994 when he was squirted with ammonia” and “was left with Limbal Stem Cell Deficiency…a painful condition which requires constant treatment,” has had sight restored in his damaged eye.
The UK’s Telegraph (12/22, Alleyne) reported that surgeons removed “a millimetre-squared section of” Turnbull’s “left eye, complete with stem cells,” then grew “it to 400 times that size in the laboratory.” Next, they stitched “the new outer skin of the eye…onto the badly damaged cornea in place of the damaged membrane.” To date, this “technique, developed by scientists and eye surgeons at the North East England Stem Cell Institute (NESCI), has been used on eight patients,” nearly “completely” restoring vision for most of those patients.
The “procedure has so far been carried out only on those who have lost their sight in one eye,” the UK’s Daily Mail (12/23, Sims, Hope) reports. However, “trials are already under way on patients who have damage to both their eyes — and millions could one day benefit from the treatment,” particularly those “whose eyes have been damaged by contact lenses, in industrial accidents involving thermal or chemical injuries, and by diseases.” Details of the procedure are published in the US journal Stem Cells.
According to the UK’s Guardian (12/22, Sample), researchers said “25 more patients will be treated before the results are submitted to Britain’s National Institute for Health and Clinical Excellence (Nice), which could approve the procedure for use in the NHS next year.” The UK’s Press Association (12/22) also covered the story.

MedPage Today (12/14, Walsh) reported that, according to a study published in the Dec. issue of the Archives of Ophthalmology, “intravitreal triamcinolone acetonide reduced progression of diabetic retinopathy more than laser photocoagulation.” After analyzing “data from a randomized trial” including “840 eyes in 693 patients,” Johns Hopkins University researchers found that “the cumulative probability of progression from nonproliferative to proliferative diabetic retinopathy at two years was” 31% for photocoagulation, 29% for “1 mg triamcinolone…P=0.64 compared with the laser group,” and 21% for “4 mg triamcinolone…P=0.005 compared with the laser group.” Nevertheless, the authors cautioned that “corticosteroids cannot be recommended at this time,” because “the treatment carries risks of cataracts and glaucoma.”   More information on eye and vision care issues visit youreyesite.com

The Los Angeles Times (12/15, Roan) reports that, according to a study published in the Dec. issue of the Archives of Ophthalmology, “17% more Americans aged 12 to 54 are afflicted with mild to severe distance vision problems than 30 years ago.” In their study, “researchers at the National Eye Institute, part of the National Institutes of Health, found that rates of myopia…in people ages 12 to 54 increased from 25% in 1971-72 to 41.6% in 1999-2004. The study included people with a range of myopia, from mild to severe.”
Study lead author, Susan Vitale, PhD, MHS, explained that “the likely cause is less outdoor time and more activities requiring close-up viewing, such as text-messaging, playing hand-held video games, and Web surfing,” Bloomberg News (12/15, Gibson) reports. Importantly, myopia “ends up costing a lot,” Vitale said, pointing out that “it costs $3.8 billion a year to treat poor distance vision, a tab that rises by $1 billion for every 12 percent increase in the rate of nearsightedness.”
MedPage Today (12/14, Fiore) reported, “The researchers noted that improved methodologies have pegged the actual prevalence of adult myopia at 33% in 2008. They said they used older formulas, which overestimated nearsightedness, on both old and new data to show the rate of growth.” Noting specific trends, the authors found that “among blacks, estimates of myopia prevalence grew faster over the period than it did among whites, more than doubling — from 13% to 33.5%.” Meanwhile, “among whites, estimated prevalence increased from 26.3% to 43%,” while overall “prevalence was…higher in 1999-2004 for all levels of myopia severity.”

In 1983, more than 10 million computers were in use in the US. By 1986 that number had more than tripled. By 1993, computer use was pervasive throughout the corporate world in America and PC usage was growing at a staggering rate throughout the US. Now it is difficult to find anyone who doesn’t use a computer for work or personal use; computers are used in police cruisers, waitresses and waiters use hand-held devices to take orders and children are spending significant amounts of their school day learning via educational computer programs. Our eyes and vision system are not adapted for working for extended periods of time at arms length distances staring at screens that generally have poor contrast. Many individuals who work at a computer monitor report a high level of job-related complaints and symptoms, including ocular discomfort, muscular strain and stress. The level of discomfort appears to increase with the amount of computer monitor use.(1.2) Visual discomfort and related symptoms occurring in computer workers must be recognized as a growing health problem (3)
Are we hurting our eyes by using computers? If so, what should we be doing to minimize the damage?
Many individuals who work at a computer monitor experience eye-related discomfort and/or visual problems. However, based on current evidence it is unlikely that the use of computer monitors causes permanent changes or damage to the eyes or visual system (4,5)
EYE AND VISION RELATED COMPLAINTS
Vision related symptoms or complaints among workers are common. Studies have found that the majority of workers experience some eye or vision symptoms (1,2,6,7,8) However, it is unclear whether these problems occur to a greater extent in workers who use computer monitors than in workers in other highly visually demanding occupations. A national survey of doctors of optometry found that more than 14% of their patients present with eye or vision-related symptoms resulting from computer work. The most common symptoms are eyestrain, headaches, blurred vision and dry or irritated eyes.(9)
The extent to which an individual may experience symptoms is largely dependent upon his/her visual abilities in relation to the visual demands of the task being performed. These vision problems are not new or unique to computer use. Many individuals in other highly visually demanding occupations will experience similar vision related problems. However, the unique characteristics and high visual demands of computer monitor work make many individuals susceptible to the development of eye and vision-related symptoms. Uncorrected vision conditions, poor computer monitor design and workplace ergonomics and a highly demanding visual task can all contribute tot he development of visual symptoms and complaints.
Vision problems experienced by computer monitor operators are generally only temporary and will decline after stopping comptuer work at the end of the day (10,11) However, some workers may experience continued impaired or reduced visual abilities, such as blurred distance vision, even after work. (12,13) If nothing is done to address the cause of the problems, they will continue to recur and perhaps worsen with future computer monitor use.
Work that is visually and physically fatiguing may result in lowered productivity, increased error rate and reduced job satisfaction. Therefore, steps should be taken to reduce the potential for development of stress and related ocular and physical discomfort in the workplace. (14,15)
VISUAL DEMANDS OF COMPUTER MONITOR WORK
Viewing a video display terminal screen is different than viewing a typewritten or printed page. Often the letters on a computer screen are not as precise or sharply defined, the level of contrast of the letters to the background is reduced and the presence of glare and reflections on the screen may make viewing more difficult (16,17).
Viewing distances and angles used for computer monitor work are also often different from those commonly used for other reading or writing tasks. As a result, the eye focusing and eye movement requirements for computer monitor work can place additional demands on the visual system. Older workers particularly may find adjusting to these working requirements difficult.
Eyeglasses or contact lenses prescribed for general use may not be adequate for computer monitor work. Specific occupational lenses prescribed to meet the unique demands of computer monitor work may be needed. (9) Special lens designs, lens powers or lens tints or coatings may help to maximize visual abilities and comfort (18) computer monitor workers who receive eye examinations and occupational eyewear have reported improved comfort and resolution of their symptoms. The quality and efficiency of their work have also been improved (19).
Some computer monitor workers may experience problems with eye focusing or eye coordination that cannot be adequately corrected with eyeglasses or contact lenses. Therapy designed to treat specific binocular vision dysfunctions may be needed. Usually the problem lies with issues of convergence, or the ability of the eyes to come together from a distant point source (far away vision – greater than 20 feet away) to a near point source such as a computer monitor.
A preventive approach to reducing visual stress from computer monitor work incorporates the use of rest or alternate task breaks throughout the workday. Many computer tasks are repetitive and can become stressful both mentally and physically after an extended period of continuous work. Occasional rest or alternate task breaks are helpful to combat fatigue and stress. They provide an opportunity to incorporate different and less visually demanding tasks into the work regimen. Specific rest or task breaks should be based on the individual needs of the computer operator.
UNCORRECTED VISION PROBLEMS
The presence of even minor vision problems can often significantly affect worker comfort and performance at a computer monitor. Uncorrected or undercorrected farsightedness, astigmatism, presbyopia and binocular vision (eye coordination and eye focusing_ problems can be major contributing factors to computer monitor eye stress. (9,21,22,23)
A high percentage of computer monitor operators has been bound to have uncorrected or undercorrected vision problems that may affect their visual performance and comfort. (24,25) Although some of these problems may not result in symptoms under less visually demanding conditions, the high demands of computer monitor work cause them to become manifest. All computer monitor workers should have a comprehensive eye examination prior to or soon after beginning computer monitor work and periodically thereafter. The examination should include careful analysis of the functioning of the eyes at intermediate and near working distances.
RADIATION EMITTED BY COMPUTER MONITORS
Like most electrical appliances, computer monitor’s emit both ionizing and non-ionizing radiation. These include visible light, ultraviolet, infrared, x-ray and radio frequency emissions. However, computer monitor emissions are often so low as to be unmeasurable or are found to be significantly below recommended safety levels. Numerous studies have been conducted to determine what effect, if any, radiation levels emitted from computer monitors may have on worker’s health. Repeated studies to date have failed to find any direct link between computer monitor use and radiation related general or eye health problems (2, 26-30) There is no evidence that radiation from computer monitors contributes to the development of cataracts.
While not technically a form of radiation, most computer monitors will build up an electrostatic charge in the vicinity of the screen surface. Static charges can cause the attraction and accumulation of dust and other airborne particles on the face of the computer screen. Although there is no conclusive evidence, it has been suggested that these charges may be related to the development of skin rash or eye irritation in some very sensitive people (31,32). This problem can usually be managed by cleaning the computer screen regularly.
WORKPLACE LIGHTING
One of the most significant environmental factors affecting computer work is lighting. Surveys indicate that many computer users report problems with general workplace lighting, glare and images reflected on the computer screen. (1,6,9) Many problems related to lighting may be caused by the introduction of computers into offices where the lighting was originally designed for traditional desk top work. The lighting is designed on the assumption that workers will perform tasks requiring their lines of sight to be depressed 20 to 40 degrees from the horizontal (4) In any situations, however, computers are placed so that viewing occurs at or even above horizontal eye level.
Bright lights in the peripheral field of view may cause discomfort glare. Windows, overhead fluorescent lights and desk lamps often contribute to this problem. These bright light sources can be controlled with proper workstation and/or room design and arrangement. An acceptable lighting level may require a compromise between that amount of light needed to enhance computer screen visibility and reduce reflections and glare and that needed to perform other office reading and work tasks. Older individuals will generally require more light than younger individuals to perform the same tasks comfortably. Workers over 50 years of age require twice the light levels of young adults for comfortable work (33)
The brightness of the screen and the surrounding room should be balanced. For dim or dark background screens this often requires using lower light levels than are used for other types of office tasks. However, lighting requirements will vary with the task. More lighting may be needed when other source documents are also viewed. In general, lighting levels between 200 and 700 lux (approximately 20 to 70 foot candles) measured at the workstation are recommended (2,34,35) More than 500 lux will usually be needed only to read poor quality documents. This additional lighting may be accomplished through the use of specific task lighting.
Light reflected from the computer screen can produce a veil of light over portions of the screen reducing contrast and visibility of the display characters. It can also form disturbing reflections of nearby or distant objects. Filters can be placed over the computer screen to reduce glare and reflections. However, filters should be considered only as a supplement, not a replacement, for control of light and reflections through proper lighting design and monitor placement. Anti-reflection coating on eyeglass lenses is a much better filter, as reflections come from around the entire work area, not just the monitor.
Windows are a major source of glare in many offices. Computer operators should avoid facing an unshaded window since the difference in brightness between the computer screen and the area behind it may be extremely stressful and uncomfortable. Operators should also not sit with their back to an unshaded window since they will cast annoying shadows on their computer screens. Adjustable shades, curtains or blinds should be sued to effectively control light levels throughout the day.
COMPUTER MONITOR WORKSTATION DESIGN AND PLACEMENT
Proper ergonomic design and adjustment of the monitor and the work environment can increase productivity and worker comfort by decreasing the visual demands of the task. Overall display legibility is an important factor in visual performance (36-39) Screen brightness and contrast should be adjusted to provide balance with room lighting and maximum visibility. Lowering screen brightness will generally reduce problems related to image stability or character flicker. Regular cleaning of the computer screen according to manufacturers’ directions will remove dust and dirt that may also interfere with screen visibility.
The color of screen characters may also affect their ease of visibility. The color of the characters can affect how the eyes focus on the computer screen and may bring about the development of harmless, but annoying, after-images for some individuals. Monochrome, or single color, displays often provide more legible images for word processing or data entry/acquisition tasks. Negative contrast computer displays (dark letters on a light background) generally provide a more legible image than positive contrast displays (light letters on a dark background). Either black characters on a white background or white characters on a black background have been found to be more visible than green, yellow-orange, blue or red characters. (16)
Adjustment of the workstation to meet the individual needs of the operator is also important for overall performance and comfort. Inadequate viewing distances and angles can impose the necessity for awkward postures when viewing a computer monitor. The direction of gaze can also affect the eyes’ focusing ability. Accommodative amplitude has been shown to be reduced with elevation of the eyes (40) The higher gaze angles at many workstations result in viewing conditions for which the amplitude of accommodation is reduced thus placing greater strain on the eyes focusing mechanism. The eyes and head should be in a slightly downward gaze when viewing a computer screen. AS a result, the top of the screen should be slightly below the horizontal eye level of the operator with no portion of the screen at an angle greater than 40 degrees below the horizontal.
Musculoskeletal problems related to head and eye postures when working at a computer are common and can often be alleviated through proper workstation adjustment. Computer workstation furniture should be adjustable and designed so that operators can easily change postures. Computer monitors that have detachable keyboards, screens that can be tilted to a comfortable viewing angle and moveable document holders allow operators to arrange the work area to their particular needs. (35) Older workers because of visual changes such as presbyopia and increased susceptibility to glare, may be especially vulnerable to problems of poor workstation design.
Some office environments have been implicated in causing eye irritation because of their dry atmosphere. The airtight environment also traps vapors and particulate matter from office furnishings. This can be a particular problem for contact lens wearers. (41) These problems can be further exacerbated by decreased blinking caused by staring at a computer monitor.
The use of computer monitors is associated with a decreased frequency of blinking and an increased rate of tear evaporation, each of which contributes to dry eyes. (42-44) The use of artificial tears can provide relief from dry eye symptoms in some cases. In addition, the width of the palpebral fissure (between upper and lower eyelids), and hence the exposed ocular surface area, can be decreased by placing the computer monitor at a lower height.
MANAGING COMPUTER MONITOR RELATED EYE HEALTH AND VISION PROBLEMS
Video display terminals are used in a broad range of occupations and their use is increasing. Many computer monitor operators experience various eye and vision related symptoms and ocular discomfort. However, many of the potential eye and/or vision problems relating to computer monitor use can be reduced or eliminated by appropriate adjustment and placement of the computer monitor, proper workplace design and lighting control, good preventive vision care habits and regular professional eye care (45, 46)
Through research and clinical practice, optometry provides unique and effective means to address the vision problems and occupational needs of computer monitor users. Computers workers and others concerned with their eye health and vision should seek the advice and assistance of doctors of optometry int heir community regarding the prevention, diagnosis, treatment and/or management of computer monitor related problems in the workplace.
The American Optometric Association will continue to develop and distribute information to improve public understanding of the importance of good vision and ergonomics related to the unique demands of computer monitor use and will monitor and offer its guidance in the development of policy and/or legislation related to the regulation and use of computer monitors.  Courtesy of the American Optometric Association
1. Smith MJ, Cohen BCF, Stammerjohn LW. An investigation of health complaints and job stress in video display operatio0ns Hunman Factors, 23:387-400, 1981
2. National Institute for Occupational Safety and Health. Potential health hazards of video display terminals. DHHS (NIOSH) publicaiotn No. 81-129. Cincinnati: National Institute of Occupational Safety and Health, 1981.
3. WORLD Health Organization. Provisional statements of WHO working group on occupational heatlh aspects in the use of visual display units. COMPUTER MONITOR news, 3(1):13, 1986
4. Panel on Impact of Video Displays, Work and Vision. Video Displays Work and Vision. Washington, DC: National Academy Press, 1983
5. Council on Scientific Affairs, American Medical Association. Health Effects of Video Display Terminals. JAMA, 257(11):1508-1512, 1987
6. Dainoff MJ, Happ A, Crane P. Visual fatigue and occupational stress in COMPUTER MONITOR operators. Human Factors, 23: 421-438, 1981
7. Staff SJ, Thompson CR, Shute SJ. Effects of video display terminals on telephone operators. Human Factors, 24:699-711, 1982
8. Rossignol AM, et al. Video display terminal use and reported health symptoms among Massachusetts clerical workers. J Occup Med, 29(2):112-118, 1987
9. Sheedy JE. Vision Problems at video display terminals: A survey of optometrists. J Am Optom Assoc, 63(10): 687-692, 1992
10. Yeow PT, Taylor SP. Effects of short-term COMPUTER MONITOR usage on visual functions. Optom Vis Sci, 66(7):459-466, 1989.
11. Yeow PT, Taylor SP. Effects of long-term visual display terminal usage on visual functions. Optom Vis Sci, 68(12):930-941
12. Gur S, Ron S. Does work with visual display units impair visual activities after work? Documenta Ophthal 79(3):253-259, 1992.
13. Kahn J, Fitz J, Psaltis P, Ide CH. Prolonged complementary chromatopsia in users of video display termianls. Am J Ophthal 98:756-758, 1984
14. Chapnik E, Gross C. Evaluation, office improvements can reduce COMPUTER MONITOR operator problems. Occup Health and Safety, 56(7):34-37, 1987.
15. Paznik MJ, Ergonomics does pay. Admin Management, August 1986, 17-24
16. Murch G. How visible is your display? Electro-optical Systems Design. March 1982, 43-49
17. Briggs R. Safety and health effects of visual display terminals, a chapter in GD Clayton and FE Clayton (eds), Patty’s Industrial hygiene and toxicology, fourth edition, vol. 1, John Wiley and Sons, inc., 1991.
18. Wan L. Task-specific computer glasses: understanding needs, reaping benefits. Occup Health and Safety 61(3):50-52, 1992
19. Barresi BJ, Rosenthal J. New York state occupational vision benefit plan study: An evaluation of a vision plan for COMPUTER MONITOR users and office workers. Center for Vision Care Policy, State University of New York/State College of Optometry, October 15, 1986.
20. American Optometric Association. Position statement on optometric vision therapy. ST. Louis: May, 1993
21. Daum KM, et al., symptoms in video display terminal operators and the presences of small refractive errors. J Am Optom Assoc 59(9): 691-697, 1988.
22. Wiggins NP, Daum KM. Visual discomfort and astigmatic refractive errors in COMPUTER MONITOR use. J Am Optom Assoc 62(9): 680-684, 1991.
23. Wiggins NP, Daum KM, Snyder CA. Effects of residual astigmatism in contact lens wear on visual discomfor in COMPUTER MONITOR use. J Am Optom Assoc 63(3):177-181, 1992
24. Rosner M, Belkin M. Video display units and visual function. Survey Ophthal, 33(6):515-522, 1989
25. Sheedy JE, Parsons SD. The video display terminal eye clinic: clinical report. Optom Vis Sci, 67(8):622-626, 1990.
26. Moss CE, et al. A report on electromagnetic radiation surveys of video display terminals. Report No. DHEW (NIOSH) 78-129. Cincinnati: National Institute for Occupational Safety and Health, 1977
27. Bureau of Radiological Health. An evaluation of radiation emission from video display terminals. HHS Publication No. FDA 81-8153. Washington, DC: Department of Health and Human Services, 1981.
28. Wolbarsht ML, et al. Electromagnetic emission from visual display units; a non-hazard. In WL Wolbarsht and DH Sliney (eds), Ocular affects of non-ionizing radiation. Bellingham, WA: Society of Photo-optical Instrumentation Engineers, 1980, pp. 187-195
29. Smith AB, et al. Report of a cross-sectioned survey of video display terminal (COMPUTER MONITOR) users at The Baltimore Sun. Cincinnati: National Institute of Occupational Safety and Health, 1982
30. Weiss MM, Petersen RC. Electromagnetic radiation emitted form video computer terminals. Am Ind Hyg Assoc J, 40:300-309, 1979.
31. Rycroft RJG, Calnan CD. Facial rashes among video display unit operators. In BG Pearce (ed) Health Hazards of COMPUTER MONITORs. New York: John Wiley and Sons, 1984
32. Nilsen A. Facial rash in visual display unit operators. Contact Dermatitis, 8(1):25028, 1982
33. Werner J, Peterzell D, Scheetz AJ. Light, vision and aging. Optom Vis Sci, 67(3):214-229, 1990.
34. New Jersey Department of Health. Guidelines for the use and functioning of video display terminals, part 1, 1989.
35. American National Standard for Human Factors Engineering of Visual Display Terminal Workstations (ANSI/HFS Standard No. 100-1988). Santa Monica, CA; Human Factors Society, Feb. 4, 1988.
36. Sheedy J. Reading performance and visual discomfort on a high resolution monitor compared to a VGA monitor. J Elec Imaging, 1(4):405-410, 1992
37. Sheedy J, McCarthy M. Reading performance and visual comfort with scale to gray compared to decimation. Displays, accepted for publication, 1994.
38. Gould J, Grischkowsky N. Doing the same work with hard copy and with cathode-ray tube (CRT) computer terminals. Human Factors 26:323-337, 1984
39. Gould J, Alfaro L, Barnes V, et al. Reading is slower from CRT displays than from paper: attempts to isolate a single variable explanation. Human Factors, 29:269-299, 1987
40. Ripple PH. Accommodative amplitude and direction of gaze. Am J Ophthal, 35:1630-1634, 1952
41. Frank C. Eye Symptoms and signs in buildings with indoor climate problems. Acta Ophthal, 64:306-311, 1986.
42. Patel S, Henderson R, Bradley L, et al. Effect of visual display unit use on blink rate and tear stability. Optom Vis Sci, 68(11):888-892
43. Yaginuma Y, Yamada H, Nagai H. Study of the relationship between lacrimation and blink in COMPUTER MONITOR work. Ergonomics, 33(6): 799-809, 1990.
44. Tsubuta K, Nakamori K. Dry eyes and Video Display Terminals. Letter to the editor, New England Journal Medicine, 328(8):584, 1993.
45. Sheedy J. Video display terminals, solving the vision problems. Problems in Optom, 2(1):1-16, 1990.
46. Sheedy J. Video display terminals, solving the environmental problems. Problems in Optom 2(1):17-31, 1990.

It happens to people every day, all over the world. They notice their distance vision worsening. They notice their children’s vision worsening. They sit by helplessly as the optometrist reads them the new, higher prescription numbers and grimace when it’s higher than they expected. They ask the Doctor “how high will it go?” hoping for an answer yet knowing there is no way to predict. “What causes it, Doctor?” not getting any clear answer, just speculation regarding genetic factors interacting with the environment and vice versa. “What can we do, Doctor?” finding the answer to that question varies doctor to doctor. Historically several methods have been used to attempt to address what we call “myopic progression”, or “myopic shift”. They include (1) under prescribing, or writing a prescription weaker than the full prescription, (2) Prescribing “Plus” for near – the equivalent of having a distance prescription and a near prescription, often achieved with bifocal or multifocal eyeglass lenses, (3) using cycloplegic eye drops, usually Atropine in a process known as “atropinization” which paralyzes the muscles that overfocus some eyes causing myopic creep, (4) prescribing hard or gas-permeable contact lenses which were suspected to help reduce change and (5) prescribing orthokeratology, understood best as “vision braces”. I will attempt to provide a basic understanding of the physiologic mechanisms believed to cause progressive myopia and what scientific evidence has shown that proves or disproves the effectiveness of the various methods offered by eye care professionals.
Myopia is defined by the Merriam-Webster dictionary as a condition in which visual images come to a focus in front of the retina of the eye resulting especially in defective vision of distant objects. The cornea of the eye, or clear front dome has a power that enables it to bend light. The “perfect” eye ( an eye with no prescription needed for perfect distance vision) has a cornea that bends light to focus precisely on the retina, or nerve layer on the back of the eye. A myopic eye can be thought of an eye where the cornea’s “power” is too weak for its length; it doesn’t allow the light to bend in concert with the retina – in essence, a myopic eye is an eye that is too long axially. A myopic eye in which the negative, or “minus” prescription is increasing (say a -2.00 to a -2.75) is actually getting longer in its axial dimension. The longer the axial dimension, the higher the prescription. The most common causes of the increase in axial length include genetic predisposition1, sustaining focused vision at distances closer than arms length for periods of time2 and decreased use of peripheral vision3.
Let’s take a look at the aforementioned methods used to manage myopia and use study data to demonstrate promise or debunk them.
UNDERPRESCRIBING EYEGLASSES
This is undoubtedly the most common method attempted to manage myopia. Historically, under prescribing has been performed by doctors in the belief that under correction slows down the worsening of myopia. This was done in the hopes of reducing near focusing strain that has been suggested as a cause of progressive myopia. Unfortunately this practice went on for a long time without any longitudinal study data to confirm that it was or was not effective. That means that tens, maybe hundreds of thousands of people have functioned with blur without knowing whether  or not it was an effective method of managing  their myopia. I frequently encounter parents  who request I under prescribe for their children.  Some people believe that this method works,  others believe that it is helpful for the eye to  attempt to adapt to a lower prescription. A  recent study 4 failed to support this idea, finding no statistically significant difference between those who received full correction and those who received under correction. Two other studies5 found that under correcting nearsightedness actually increased the rate of its progression. Under correcting myopia is therefore not a proven strategy for slowing the progression of nearsightedness in children. It also has the disadvantage of causing blurred distance vision if the treatment is performed with single vision lenses.

PRESCRIPTION OF BIFOCAL OR MULTIFOCAL EYEGLASSES
We have stated that doctors believed that under prescribing works by reducing near eyestrain. While many doctors and parents attempted to under prescribe the entire prescription, others felt under prescribing distance vision puts the patient at a disadvantage yet desire the patient have less prescription when viewing near objects. To achieve this, they prescribe adult “bifocals” or “multifocals” – lenses that provide the proper distance prescription when viewing distance targets and a lower near prescription when looking lower to read or use a computer. Two studies 6,7 have shown a small, but statistically significant decrease in progression of myopia in the first year of wearing the multifocals which remained similar and significant for the next 2 years. This method is more successful in people with certain types of eyes; those who “over accommodate” and/or manifest a slight eye deviation inwards, known as esophoria. In our practice we often offer this as an option for parents with children who are slightly esophoric and manifesting prescription change greater than 2 steps (.50 diopters) per year.

CYCLOPLEGIC EYEDROPS
Drops known as Cycloplegics are used to paralyze the muscles that focus to provide near vision through the process known as accommodation. The most common cycloplegic agent used is Atropine, and the process of using Atropine is termed “Atropinization”. The theory behind cycloplegics is that by minimizing accommodation, the continued growth of the axial length of the eye is controlled. Several studies have consistently shown a beneficial effect for proper atropinization. In one study8, sixty-two children were treated with atropine in one eye for one year; the fellow eye was the control. The eyes were switched the second year. Twenty-eight patients were treated for four years on the same basis. Control eyes showed significant increases in myopia compared to treated eyes. Some treated eyes showed decreases in myopia; no decreases were seen in control eyes. Post treatment data analysis indicated the effects are long-term. In other studies 9,10, after stopping treatment, eyes treated with atropine demonstrated higher rates of myopia progression compared with eyes treated with placebo. However, the absolute myopia progression after 3 years was significantly lower in the atropine group compared with placebo. Still another study showed similar benefits using a different cycloplegic agent Pirenzepine11. Atropinization is rather severe and can limits a child’s function at near as Atropine paralyzes their ability to focus up close – they must use reading glasses for near work. While we offer this option to patients, it is not the most popular option.
HARD AND RIGID GAS PERMEABLE CONTACT LENSES
In the late 1950’s the first plastic hard lenses were mainstreamed. Prior to plastic hard lenses, glasses had been the only mainstream vision correction option. Doctors noted after a few years a significant percentage of the patients who were wearing hard lenses seemed to manifest a reduction in the amount of myopic “creep” year to year. Early studies produced intriguing results for scientists and clinicians, but contain many problems that challenge the significance of the studies’ findings; studies failed to provide proper attention to many important variables. In more recent and better controlled studies, researchers found that rigid gas permeable contact lenses slow the progression of myopia (nearsightedness) in young children12,13,14. The difference in myopia progression between the rigid gas permeable contact lens wearers and the soft contact lens wearers was 0.63 diopters (D). Although the myopia of children assigned to wear rigid gas permeable contact lenses progressed less than the myopia of children assigned to wear soft contact lenses, the difference is not enough to warrant prescribing rigid gas permeable contact lenses solely for the purpose of slowing the progression of nearsightedness. Researchers also found that rigid gas permeable contact lenses do not slow the growth of the eye, which is responsible for the majority of myopia in children. Instead of slowing the growth of the eye, rigid gas permeable contact lenses kept the cornea from changing shape more than soft contact lenses. The change in the cornea is not likely to be a permanent change, so the effect of rigid gas permeable contact lenses on myopia progression may not be permanent.

ORTHOKERATOLOGY
Another interesting finding around the time that hard lenses were mainstreamed was that some patients reported being able to see clearly, or clearer, at distance without glasses after they removed their hard or gas permeable contact lenses. It didn’t take long for doctors to realize that lenses that were fit flatter than the curve of the cornea were responsible for this finding. The art and science of prescribing lenses with a curve flatter than that of the cornea is known as Orthokeratology.   Now, Orthokeratology is purposefully prescribed to provide patients a refractive option that allows people to see without glasses or contacts during their waking hours. Since orthokeratology is performed with hard but preferably gas permeable contact lenses, doctors believed that it also may help limit the progression of nearsightedness. Recently it has been shown15 that Ortho-k can have both a corrective and preventive/control effect in childhood myopia. However, there are substantial variations in changes in eye length among children and there is no way to predict the effect for individual subjects. A new study, called the Corneal Reshaping and Yearly Observation of Nearsightedness (CRAYON) study, is now underway and has confirmed that corneal reshaping with specially designed gas permeable contact lenses does indeed slow eye growth in myopic children at one year of treatment. We have a very lage orthokeratology practice. OrthoK seems to be the method of choice due to it’sconvenience, ease of use and positive study data. Parents who choose OrthoK for their children need to be aware of the benefits and risks of sleeping in contact lenses. They should be educated as to the signs and symptoms of an infection or inflammation. They should also know not to use tap water or distilled water at any time to clean their lenses or lens cases. Lens cases should be cleaned every night as they have been identified as the source of most infections in overnight lens wear.
Summary
Every day in our practice we talk with parents concerned about their childs worsening vision. While myopia “creep” is a reality, the big picture regarding what the “creep” ultimately means has changed since the advent of laser vision correction. When parents were young, the perception was that whatever change occurred did so permanently, relegating the child to strong eyeglasses or contact lenses the rest of their life. The concept of eventually reversing the change with laser refractive surgery didn’t exist. Now there is a somewhat permanent solution to higher levels of nearsightedness at the end of the road for most people with myopia and astigmatism – light at the end of the tunnel, pun intended. Myopia no longer has to mean a lifetime of wearing glasses or contact lenses. If viewed from this perspective parents may take solace in knowing that even though their child will deal with a period in his/her life where they are dependent on refractive correction, there is light at the end of the tunnel. Their child is likely to have the opportunity to experience life without contacts and glasses again. This is a generational shift in thought brought on by technological advances. A relevant long term strategy for many parents is manage as best as one can by using available myopia control methods that demonstrate efficacy according to solidly designed scientific studies with the long term view that whatever happens, options exist to improve the childs quality of life with surgery as an adult.

Copyright 2009 – Dr. Alan N. Glazier, Optometrist, PA – All Rights Reserved

1. Eye (Lond). 2008 Apr;22(4):576-81. Epub 2007 Oct 19
2. Ojaimi E, Rose KA, Smith W, Morgan IG, Martin FJ, Mitchell P.,University of Sydney, Department of Ophthalmology (Centre for Vision Research, Westmead Hospital) and the Westmead Millennium Institute, Westmead, New South Wales, Australia
3. Invest Ophthalmol Vis Sci. 2005 November; 46(11): 3965–3972.
4. The possible effect of undercorrection on myopic progression in children. Clinical & Experimental Optometry. September 2006.
5. Undercorrection studies: Eye correction is seriously short sighted. New Scientist. November 2002.
6. COMET study: A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. Investigative Ophthalmology and Visual Science. April 2003.
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9. Ophthalmology, Volume 116, Issue 3, Pages 572-579 (March 2009)
10. Ophthalmology. December 2006.
11. Ophthalmology. January 2005.
12. Walline JJ, Jones LA, Mutti DO, and Zanik K: A Randomized Trial of the Effect of Rigid Contact Lenses on Myopia Progression. Arch Ophthalmol 122: 1760-1766, 2004
13. CLAMP study: A randomized trial of the effect of rigid contact lenses on myopia progression. Archives of Ophthalmology. December 2004
14. Singapore study: A randomized trial of rigid gas permeable contact lenses to reduce progression of children’s myopia. American Journal of Ophthalmology. July 2003
15. LORIC study Curr Eye Res. 2005 Jan;30(1):71-80

Artificial Retina Video  CNN (12/11, Smith) reported that retinitis pigmentosa patient Barbara Campbell of New York “is one of only 14 people in the” US “participating in an FDA-approved study of” a second-generation “artificial retina” with 60 electrodes. This past July, “Campbell underwent surgery to implant the microchip into her eye” and now “wears a pair of sunglasses outfitted with a small camera. As she scans and focuses the camera on an object in her environment…a wireless device transmits that image to the artificial retina inside her eye,” providing her with a “rudimentary level of vision” that allows her to see light. Scientists are now developing devices with many more electrodes to provide “more detailed vision.”

Along with advances in other areas of technology, the 21st century has seen huge advances in contact lens technologies. Lenses that are healthier, thinner, more comfortable, easier to care for, work with dry eyes and provide vision for difficult prescriptions have flooded the market in recent years. Even hard lenses are more comfortable thanks to these advances. If you have tried contact lenses more than 5 years ago and were unsuccessful it might be time to revisit the newer technologies with your optometrist.
Corneal Refractive Therapy (Orthokeratology)
An alternative to LASIK and other surgical methods of correcting vision, Corneal Refractive Therapy (Orthokeratology or Ortho-K) offers people a non-surgical method of achieving vision without contact lenses or glasses while awake. A special lens is fitted for the eye which the patient sleeps in, and upon awakening removes. Most people are able to go for at least one day without contacts or glasses after sleeping in the lens. Doctors should be careful not to offer this therapy as a solution to vision problems, it is only a temporary non-surgical alternative to glasses and contact lenses. Not every doctor fits Ortho-k, so be sure to ask. Ortho-K is gaining in popularity in the US and is already popular overseas. If you are bothered by annual changes in your eyeglass and contact lens prescription or are concerned that your vision is worsening, OrthoK may be the solution for you.  OrthoK in many cases temporarily reverses significant amounts of myopia and astigmatism and in most cases people who wear their OrthoK devices while asleep can go contact lens and eyeglass free with excellent vision during waking hours! OrthoK is the only way doctors know that can reduce the rate of change of your eyeglass prescription and in some cases stabilize your eyeglass prescription. Click this link to view studies that have shown a positive effect in stabilizing worsening vision.

Multifocal Contact Lenses for distance and reading vision issues

If you are on the far side of 40, you are probably finding that reading the phone book or newspaper is suddenly a chore. Welcome to middle age, and a condition called Presbyopia. Presbyopia, a type of farsightedness inevitable with aging, is caused by the gradual changes in the lens within the eye. It becomes less able to change shape, preventing us from focusing on close objects. Most people become aware of deteriorating close vision in their mid-40’s. Many people turn to inexpensive reading glasses, but it’s important to have regular eye exams. Prescription reading glasses and bifocals allow a close-up correction giving the best possible vision for close, but many are bothered by the tell tale line in a bifocal. Contact lenses offer several options for the correction of Presbyopia, including Multi-focal contact lenses, Bifocal contact lenses and Mono-vision. Multi-focal and Bi-focal contact lenses generally are without lines, and there is very little adaptation, unlike multi-focal and bi-focal eyeglass lenses. They are exceptionally difficult to fit from the doctor’s standpoint, so be patient as you may visit your doctor several times during your fitting to achieve maximal vision. Most patient’s are extremely pleased with their multifocal contact lenses if fit properly, and leave the office seeing better at near immediately. These lenses are even good for people who have never worn contacts before, so be sure you find a qualified eye doctor to prescribe them.  Researchers have achieved success with new designs of Bifocal and multifocal contact lenses. These newer soft (often available as disposable) contact lenses provide patients with distance, intermediate and near vision and has proven to be much more successful than bifocal contact lens predecessors if fit properly. In the past, bifocal contact lenses were successful in less than 40 percent of patients who tried to wear them. They also were prohibitively expensive and in many cases would end up on the medicine shelf after weeks or months of wearing attempts. The new class of Multifocal lenses are comfortable, easy to use and adapt to and are relatively inexpensive. The patient has it easy with these lenses; adaptation is fast. . . the doctor must spend time analyzing the prescription to maximize vision with the lens. The new Multifocal lens designs can give you your young eyes back! No more one eye near, one eye far (monovision) – this is the real deal and they work!

Limbal and Scleral Lenses – a new, comfortable substitute for hard and gas permeable contacts

Although the standard “hard lens” introduced in the 1950’s are still around, newer materials developed have made these lenses virtually obsolete. RGP lenses are made of special, firm plastics suited for the transmission of oxygen and other gasses necessary to maintain eye health. These lenses are very durable and typically last longer than soft lenses, sometimes more than 2 years. RGP lenses offer crisper vision than soft and are often preferred by people with high myopia, astigmatism or other hard-to-fit contact lens patient’s. Historically they have taken a while to get used to, regular wearers find them comfortable and the visual acuity outstanding. Problems with these lenses include tolerance in dusty environments. Large diameter lenses are the latest technological advancement in the gas permeable lens arena. The larger lenses provide the excellent vision favored by those who wear gas permeable contact lenses while achieving much greater comfort for the user than their smaller counterparts. They also are able to retain their high level of oxygen permeability. They are known as Limbal and/or Scleral lenses.

Copyright 2009 – Dr. Alan N. Glazier, Optometrist P.A. All rights reserved

The doctors at youreyesite.com want to convey that the following information is non-scientific and based on one individuals experience.  Please use your own judgement and scrutiny when digesting this material.  Consult the following link for scientific information on nutrition and vision

The UK’s Daily Mail (12/11) reports that retired UK optician Harry Marsland, who suffers from age-related macular degeneration (AMD), “could be the first person in the UK to have recovered from” that “devastating condition.” Since he began taking 2 mg daily of “a food supplement containing marigold extracts” in early 2007, Marsland says that “he is driving a car again, reads without a magnifier, and has near-perfect vision in the affected eye.” The Daily Mail explains that the “vitamin supplement, called Macushield,” costs £150 (approximately $245) for a year’s supply, and “is not available on the NHS.”
The UK’s Telegraph (12/11, Wardrop) points out that the supplement taken by Marsland “contains lutein, found in spinach, and zeaxanthin, the yellow pigment found in corn,” as well as “mesozeaxanthin, derived from marigolds.” Marsland claims to “have recovered 95 percent of the sight in” his left eye.