Orthokeratology has been proven to decrease the progression of myopia in school-aged children, according to a number of studies. Orthokeratology has recently been regarded among the most effective optical treatments for myopia management.
This study examined peer-reviewed research on the effectiveness of Orthokeratology in the treatment of myopia. However, even while myopia advancement cannot be halted completely, Ortho-K it has been shown to have an inhibitory effect of between 32% and 63% compared to single-vision glasses and soft contact lenses over the course of two years.
In addition, multiple studies with up to ten years of data have verified the efficacy and acceptable safety of the therapy.
Myopia progression following Orthokeratology discontinuation may or may not see a rebound phenomenon. It’s also not obvious how long each patient should continue treatment to get the most out of it.
Longer follow-up periods across a broader range of people are needed in the near future to better examine if myopia progression rebounds.
First, marketers begin with the statement that blue light is dangerous to our eyes, skin, and sleep patterns. This is factually correct, but somewhat intellectually dishonest.
“It’s true that blue and ultraviolet light are dangerous to eyes, but only at very high intensities. The amount of blue light produced by a computer monitor or phone screen is so dim that it has no effect on the health of the eyes. The blue and UV light from the sun is very dangerous and is a documented source of skin cancer, cataracts and retina disease to millions. This is why doctors recommend sunglasses and sunscreen to people spending significant time outdoors.”
– Dr. Norman Shedlo
Flicker Rates
If you have ever noticed the flicker of a monitor or other display, you will agree that the flicker can be aggravating and unpleasant to look at. But the important question here is whether or not a “flicker-free” monitor does anything to protect your eyes.
Again, we turn to the experts. Dr. Shedlo tells us that “flicker rates between 70-90 Hz will present a screen that does not appear to ‘flicker’. The flickering itself is not dangerous to your eyes, it’s just annoying. Flicker rates above this are outside the range of human perception and make absolutely no difference. These rates have no effect on eye strain.”
We discussed the topic with Dr. Yuna Rapoport, an Ophthalmologist and owner of Manhattan Eye.
Most of the eye strain that occurs happens because of dry eye and decreased blink. So, while special flicker free monitors and monitor lamps seem fancy and may provide a better user experience, from a medical point of view they do not ‘save the eyes.’
– Dr. Yuna Rapoport
We asked our experts a few simple questions: Would you recommend a special eye care monitor for a friend or family member? And would you pay extra for an eye saving monitor?
Dr. Rapoport stated that she does not “think that they are worth the extra price,” and she “would not get one for myself or for a loved one.”
Dr. Shedlo replied that he “would not pay extra for any eye health benefits claimed by these technologies.”
If we are looking solely at the science and the expert advice, there is insufficient evidence to suggest that eye care monitors actually improve eye health.
Monitor Lamps
The concept behind monitor lamps, monitor light bars, and monitor bias lighting is relatively simple. These products minimize the lighting contrast between your monitor and the surrounding area. A bright display in a dark room causes strain on the eyes, so it is better to have some ambient lighting near your computer.
So, these products probably help minimize eye strain when compared to using no monitor lighting at all. But that doesn’t mean that it makes sense to spend $100+ for a specialty monitor light bar that claims it will save your eyes. Ultimately, these monitor lamps and light bars are simply, as Dr. Shedlo puts it, “smaller lamps placed on the monitor to provide lighting to certain places on the desk. Their function can be substituted for by any suitable desk lamp pointed in the right direction.”
However, much of this “eye saving” technology is actually just marketing hype. As Dr. Shedlo puts it, these computer companies use language that is “scientific and technical [to give] the impression of legitimate benefits based on scientific data.” But “the claims about the relationship of new monitors to eye health have no basis in reality.”
One of the most difficult challenges in myopia control is identifying whether or not patients are receiving a significant therapy benefit. This has been a problem because patients of different ages progress at varying rates, and we can never truly know how far an individual patient would have advanced if they hadn’t received treatment.
A good example of this is the typical 7-year-old non-Asian patient progressing by –1.00D in refractive error and 0.35mm in axial length per year, but the average 12-year-old non-Asian patient progresses by –0.40D in refractive error and 0.21mm in axial length per year.
Individuals of Asian descent make slightly more progress than patients of non-Asian descent. The prevalent thinking that a myope develops 0.50D per year on average only holds true for people of a specific age and racial group (those under the age of ten).
In addition, it is crucial to remember that emmetropic patients might have a neutral refractive error while still experiencing around 0.1mm of axial length advancement per year.
Recently published evidence suggests that the maximal axial length slowing experienced by a myope treated with a multifocal soft contact lens may be similar to that seen by an emmetrope in some cases.
As a result, it is unlikely that we will be able to completely halt axial length growth in children who are still growing. In addition, it is vital to remember that these are averages, which means that certain patients will progress more rapidly than the average myope.
What can we do with this information to determine the effectiveness of myopia management treatments? Efficacy is determined by observing that individuals progress less than the mean value for their age and race after undergoing a particular treatment.
While this is not a perfect sign of effectiveness, it does provide us with some foundation for determining whether a treatment is helpful, and we will most likely continue to rely on this type of data until studies that speak to the effectiveness of treatments in individual patients are conducted.
We discuss with families the potential benefits of combination therapy after at least one year of treatment. Nonetheless, it is up to the parents, after they have been educated, to decide whether or not to change the course of therapy.
Clinical relevance: This paper provides eye care practitioners with important information about the potential side effects of 0.01% atropine.
Background: Eye care practitioners routinely administer 0.01% atropine eye drops nightly to slow the progression of myopia, but nobody has assessed accommodative lag or facility, near phoria, intraocular pressure or comfort of drop administration.
Methods: All 21- to 30-year-old adults with no history of accommodative issues or therapy were eligible. During the baseline visit, participants underwent testing related to potential side effects. Participants then administered one drop of 0.01% atropine nightly to both eyes, and all tests were repeated 1 week later.
Results: The average ± standard deviation age of the 31 participants was 23.9 ± 1.6 years, 71% were female, and 81% were Caucasian. The only significant changes were an increase in photopic pupil size from 4.9 ± 0.8 at baseline to 5.1 ± 0.6 mm after 1 week (paired sample t-test, p = 0.002) and an increase of the average intraocular pressure of the two eyes from 15.6 ± 2.7 to 16.7 ± 3.1 mmHg (paired-sample t-test, p = 0.003), but neither of these changes was clinically meaningful. There were no other statistically significant differences before and after 1-week administration of 0.01% atropine for any of the vision, accommodation, reading speed or subjective side effects. When asked how likely they would be to take the atropine drops to delay the onset of myopia on a scale from 1 (definitely not) to 10 (definitely would), participants replied with an average of 8.2 ± 2.0 after taking atropine eye drops for 1 week (paired-sample t-test, p = 0.81).
Conclusion: Nightly administration of 0.01% atropine did not result in any clinically meaningful symptoms, so patients would be very likely to take the drops to delay the onset of myopia.
Cyphers B, Huang J, Walline JJ. Symptoms and ocular findings associated with administration of 0.01% atropine in young adults. Clin Exp Optom. 2022 Feb 20:1-11. doi: 10.1080/08164622.2022.2033603. Epub ahead of print. PMID: 35188076.
The Projector Rainbow Effect can be a major annoyance to home theater owners. This is because it can significantly reduce the image quality and make the picture look blurry. In some cases, the projector rainbow effect can even be mistaken for a defect in the projector. The projector rainbow effect is visible on the projection screen as a series of red, green and blue bands that appear to be layered over each other.
In a digital light processing (DLP) projector that uses a single chip, a rotating color wheel in front of the monochromatic light source projects sequential images in different colors rapidly on the screen. The visual system of the observer combines the different colors into one image in the brain producing color motion pictures from a white light source. Unfortunately, the system is not perfect. Some individuals are not able to completely merge the different color images in their mind and individual colors are still perceived creating a “rainbow effect” around high contract images. The effect is made worse if the individual moves their eyes. Speeding up the rotation of the color wheel helps to lessen the effect but does not remove it entirely.
The reason this happens is that moving objects and colors are processed by two different parts of the visual system. The magnocellular pathway processes the movement and position of objects in the field of view and the parvocellular pathway processes the shape and color of objects in the field of view. These pathways begin in the retina eye and continue to the lateral geniculate in the thalamus portion of the brain. The retinal rod cells are more sensitive to movement and the cone cells are more sensitive to color. A slight mismatch in the signals the brain is receiving from the color pathway to the ones being received from the motion pathway lead to a perception of “rainbows”. This effect is similar to a video of someone speaking that is not exactly synced to the audio portion of them speaking.
About 40% of individuals notice this effect. This may be for several reasons; some individual may not pay attention to it, the type of media being viewed may exhibit less of the effect such a lower contrast and slower action, differing eye and brain anatomy that may have different lengths and quality of the magnocellular and parvocellular pathways and increased eye movements in some individuals when watching these projections.
