Another year is about to wrap up, and there has been plenty of excitement and change in the world of eyecare in 2014.  Today I'm bringing us into 2015 with a review of the top stories that brought you to the website and that shaped the face of optometry in this past year.  The more popular articles are always so telling about what we really care about, and next year I plan to continue bringing you the latest in technology updates, fashion posts, and patient education.

Top Industry/Technology Posts of 2015

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• This year was all about the contact lens changes, from the continued interest and growing support of Ciba's Dailies Total 1 (our review of DT1 is the second most popular/viewed post all time on Eyedolatry, right behind perennial favorite, conjunctival cyst) to new lenses like Bausch and Lomb's Ultra (the fourth most popular/viewed post all time on Eyedolatry).  
• A number of color contact lenses were discontinued in 2013 and 2014 (Freshlook, Focus Softcolor, and Acuvue 2 Colors), but we did get the launch of a new, higher oxygen color contact lens in Air Optix Colors. 
• The use of Lucentis versus Avastin was a topic of a ton of interest after articles reporting on the most recent Medicare review seemed to put a bad light on the ophthalmogists using the more expensive product.  You can check out the full info and why your doctor may prefer Lucentis for your eyes in this post.
• Tons of new innovations from artificial tears to telescopic implants became available for use this year:

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• Retaine MGD -- a great artificial tear made by Ocusoft hit mainstream pharmacies
• CentraSight telescopic implant for advanced macular degeneration lowered its age requirements in October 2014 so that more people could take advantage of this new technology
• LensPen introduced its Peeps glasses cleaner that uses high-tech ionic charges to remove pesky smudges from your glasses without risking a scratch.
• Bausch and Lomb released their new take on hydrogen peroxide contact lens deep cleaning with PeroxiClear, making your lenses feel like new day after day.

It's not too late!  If you are in need of a few last minute gifts or stocking stuffers for the glasses obsessed individual in your life (or basically any optometrist because we are by definition obsessed with eyes) then we have you covered in today's post.

This affordable tumbler will make any optometrist happy -- "one or two" jokes are a part of our life.  Find this on Etsy.

Looking to splurge?  These Del Toro slippers are going to set you back, but will definitely spark a conversation.  Find them here.

Another great Etsy find, this cuff bracelet is perfect for the optometrist.  Find it on Etsy.

This is the perfect stocking stuffer for any glasses wearer.  The LensPen Peeps cleaner will remove smudges without risking scratches, and are the perfect size to keep in a desk drawer, in your purse, or even in your pocket.  Find them here.

Evil Eye Jewelry is having a major moment, so take advantage of all of the eye-love while it is on holiday sale!

Studio Silver 18k Gold over Sterling Silver Ring, Crystal Evil Eye Ring •

RACHEL Rachel Roy Ring, Abalone Evil Eye

If you have found this little corner of the internet, you probably really care about learning about your eyes.  The longer I have been blogging about ocular health, I am repeatedly blown away by the other talented and intelligent eye care specialists sharing their knowledge on the internet for patients they will likely never meet but they are helping and educating nonetheless.  Today I wanted to share some of my favorite optometrists and ophthalmologists blogging about their fields so that you can find even more of the information you seek about your ocular health!

To fully investigate visual problems, we need to establish an idea of how the eyes behave both independently and together.  Checking visual acuity is not enough; a person may have clear vision but still suffer from double vision or ocular strain because the eyes aren’t working efficiently together.  Today we break down one of  Dr. S’s most essential tests in her normal battery of VT work-up items: the cover test.  “You can get so much information when doing a cover test, especially if you take the time to examine the effect of fatigue.”

Cover Testing

What it Tells You:  Ocular alignment and how much stress the visual system can take before binocularity (the ability to use both eyes together) breaks down.  Another way to think of this is how fragile your patient’s binocularity is, or the likelihood that the patient experiences diplopia or fatigue with fine detail tasks in distance and/or at near.

Strabismus is the scientific word for an ocular misalignment where the two eyes do not naturally
focus on the same central point.  The eyes will point in different directions at the same time for any givenlength of time – be it constantly or only under certain activities. Other layman terms often associated are“squint” or “cross-eyed”

• The term tropia is used to define the direction of the strabismus (or misalignment).  For example, an exotropia means that the misalignment occurs due to one eye deviating outwards.  An esotropia is a deviation inwards.  Vertical misalignment is also possible: hypertropia means deviated upward and hypotropia means deviated downward.

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• A phoria is a misalignment that occurs only after the eye has been fatigued; it is a tendency for the eyes to deviate in any direction – vertically or horizontally - but the visual system is able to compensate well enough for the deviation that it does not manifest as a tropia.  A phoria will often present with visual, mental, or physical fatigue.  In medical literature you may see the term “latent deviation,” meaning that the misalignment is not always present.  This person does not have strabismus (the eyes are correctly aligned), but due to ocular stress and fatigue the eyes may become temporarily misaligned. Phorias can be labelled as exophoria (outward deviation) or esophoria (inward deviation).

Cover Testing is used to uncover the presence of tropias and phorias.

Equipment You Need:

• Use a fine detail target and have the patient wear their appropriate glasses for the distance or near target to achieve best vision
• at distance you can isolate a 20/30 size letter or picture on the chart (or larger if their acuity is reduced)
• at near you can use:
• a small letter on a card or target
• a small or fine detail point on a picture ---“Look at the elephant’s trunk”
• or the patient’s own reflection in a Wolff wand – great for younger patients!
• an Occluder or some way to isolate the two eyes (be that a dark piece of paper or even your hand that can be moved in front of each eye if you are in need of a quick assessment)

How to Perform: Cover Testing is typically done at both near (around 40 cm) and far (with a target set for 20 feet) to assess ocular alignment.  Testing at near is very important – the patient may achieve ocular alignment when they are looking at a distance, but when they move to doing near work their eyes may have much more difficulty.  It is quite common to see larger misalignment or deviations with near testing than you would find with distance testing, especially if there is a concurrent accommodation (or focusing) issue.  In addition, if a patient presents with a distance complaint, careful near testing may reveal why the eyes are experiencing distance blur or diplopia (more to come on this in future posts!).

In cover testing you are looking for ocular movement to determine the presence and direction of tropia or phoria.  If the eye moves inward after being uncovered (or moves outward when covered, asviewed with a translucent occluder or by peeking behind the occluder), then you have an exo deviation.  If the eye moves outward after being uncovered, then you have an eso deviation.

Steps:

1. Unilateral Testing:

• Occlude one eye, and observe the uncovered eye for movement
• If the uncovered eye moves toward the patient’s nose (inward) when covering the fellow eye, an exotropia is present. 
• If the uncovered eye moves away from the patient’s nose (outward) when covering the fellow eye, an esotropia is present.
• Quantifying the angle using prism is necessary, as the angle may change with fatigue.
• Qualifying the tropia as constant or intermittent, or monocular or alternating is also important
• Ask yourself: with an alternating tropia, which eye does the patient tend to fixate with?
• Repeat on the left eye.

**If you note movement on Unilateral Testing, you have found a tropia

2. Alternate Testing:

• Cover the right eye for 3 seconds, and then switch to cover the left eye.  
• Repeat, waiting 3 seconds in between movements to allow time for the eyes to re-find your test target.
• Immediately observe the uncovered eye for movement.
• if the eye moves “with” your occluder you have an exo deviation.
• if the eye moves “against” your occluder movement in eso deviation

**If you note movement on Alternate Testing, you have found a phoria

3. Repeat Unilateral Testing

• If you truly have a phoria, you will see misalignment on the alternating cover test, but the patient will have normal alignment when you repeat the unilateral testing.  If instead you now see misalignment on the unilateral testing, this person actually has a tropia that maynow be easier to detect since the eyes are more fatigued

Tips from Dr. S:

• When using prism to quantify angles of deviation, careful attention is needed to observe smaller angles.  Sometimes the angle of deviation is so small that you cannot observe it, but the patient will report a “jump” when switching the paddle from one eye to another, or when uncovering the eyes completely. The direction in which their target is jumping will let you know how the eye is deviating.  For instance, if during an alternating cover test that appears ortho, but the patient reports the target “jumps” to the left when you go from covering the right eye to covering the left eye, an exophoria is present due to the report of crossed diplopia.
• If you don't see any movement on unilateral testing, but vision is reduced in one eye, you can perform a quick Bruckner/Hirschberg test with your direct scope and immediately see the amblyopia or strabismus.  Sometimes after strabismus surgery, the deviation is SO SMALL, but the strabismus still remains so their vision will be less than 20/20. 

Take Home:

The key hallmark of cover testing is revealing and differentiating strabismus (full time deviations) from phorias (latent deviations).  Alternate cover testing cannot differentiate phoria from tropia, so you have to perform unilateral testing to determine that difference.  Unilateral testing can also
tell you if you have an alternating tropia, or a single eye misalignment.  Patients with constant alternating tropias may have more equal acuitieswhen comparing the right and left eyes, but they still suffer from loss of depth perception because they can’t have binocularity.  In the case of a (constant) one-eye deviation, that eye is at risk for developing amblyopia, which includes reduced vision, as well as reduced accommodation and ocular motor deficiencies..  Vision can’t develop clearly in a constantly strabismic eye because the image is being constantly suppressed and ignored by the brain. With constant alternating deviations, each eye is getting visual use during the day at some point, so visual information is still being processed by both eyes.  That is why it may be less likely to have strabismic amblyopia in a patient with constant alternating strabismus than in a unilateral trope where the deviated eye is never being used.

Determining the type of ocular misalignment helps your doctor develop the best plan for achieving better visual performance.  A patient with a large unilateral strabismus may prefer to pursue strabismus surgery to help gain alignment, along with strabismus vision therapy to gain visual function and binocularity after surgery.  Conversely, a patient with only a phoria or an intermittent tropia is much less likely to be a candidate for surgery because their eyes aren’t always misaligned and the patient may be able to learn to expand their range of fusion without surgery in most cases. There is even a risk in surgeries in patients with intermittent tropias that what binocularity does exist could be eliminated after surgery due to the common subtle vertical deviations and nystagmus than can occur after a strabismus surgery.  The “VT sandwich” is a great approach: your vision therapy optometrist and your strabismus surgeon will work together as a team to achieve best visual outcomes by employing vision therapy before surgery to establish awareness, limit suppression, and increase visual acuity, and if possible to pinpoint a centration point for the eyes to focus in space together. Then surgery will be performed with the aim of moving the deviant eye to that centration point to achieve the best possibility for ocular alignment.  After surgery vision therapy can help the patient fine tune their ocular function and work towards achieving the chief goal: (functional) binocularity.

Phorias are very common in my average patient base – if you sometimes see double or feel your eyes fighting to stay focused together after long hours reading or on the computer, you probably have a phoria.  Patients with phorias can learn how to better control their ocular muscles to keep their eyes aligned, even with fatigue.  And that is just one example of what vision therapy can help a person achieve!

Dr. S is a residency trained optometrist and COVD fellow specializing in Vision Therapy

The good news?  This finding is very normal, but can give you quite a start when you see it for the first time! Myelinated nerve fiber layer is a benign finding where the myelin sheath that typically lines and insulates the optic nerve when it exists the eye, persist even inside the eye. Normally, the myelin sheath stops before the nerve enters the eye because myelin (the dense white material you see above the nerve in this photo) will prevent light information from reaching any retinal cells underneath it. Myelin sheathing of the nerve is essential to visual function because it speeds up the transmission of information from the eye to the brain.  But if it exists inside the eye, there may be some (usually very subtle) visual loss since myelin is not clear and therefore any cells stuck behind it won't be able to detect light when it enters the eye.

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Pantone recently released the 2015 color of the year: Marsala, a deep red wine and burgundy-esque color.  While there are always mixed reviews when the color of the year is announced, eyewear has been embracing the dark burgundy trend on the runways all year for good reason.  Yesterday's candy colored plastics are quickly fading into memory in exchange for a darker and more sophisticated eyewear color palate.  Marsala keeps the trend of embracing color in play (I loathe a day where all glasses are black or brown or metal), but with a much more subdued effect than the bright neons we've been seeing in eyewear the past few years.  This color mixes perfectly with the metal accents and amber tinted lenses we've seen from many designers as the retro looks from the 70s have returned to fashion (round eyewear is everywhere!).

Pantone Color of the Year advertisement (featuring eyewear!) via

Looking to embrace the trend?  Go all out in deep red frames or you can even pair a metal or thin rimmed plastic frame with a burgundy hued tinted lens.  Here's a look at some of the best glasses options embracing the Marsala color trend for 2015:

Images will link to brand below with affiliate linking.

The world is moving to either single use or silicone hydrogel contact lenses, and CooperVision acknowledged that trend recently by announcing plans to discontinue some of its older hydrogel contact lens options. They cited a major movement in contact lens fitting trends in the first few months of 2014:  44% of hydrogel lens wearers were refit to silicone hydrogel lenses and 44% of multiple wear lens wearers were refit into daily disposables (data from CooperVision).  With so many options for better health and better comfort, the days of old hydrogrel lenses seem to be numbered with multiple companies restructuring their product lineups to ditch old materials in favor of healthier options.

I was surprised to see Proclear EP as a discontinued lens since I do find it effective for very early presbyopia, but full multifocal contact lenses are getting better at limiting distance distortion, and using a silicone hydrogel lens like Biofinity MF with low adds will give the added benefit of monthly lens wear and higher oxygen transmissibility.  via

The three lenses that are being discontinued are Biomedics 55 UV, Biomedics 38, and Proclear EP. As of 12/31/2014 trial lenses will no longer be available for order, and no boxes will be available to purchase in any of these lens products as of 10/31/2015.  Here are the recommended refit options for the products being discontinued:

Biomedics 55 UV and Biomedics 38 (also called Sofmed or Ultraflex):

• to keep with 2 week disposal, refit to Avaira
• to change to monthly disposal, refit to Biofinity
• upgrade to daily disposable

Leber's Congenital Amaurosis results in photoreceptor death and significant visual loss in childhood. via

If you know someone affected by the blinding genetic condition, Leber's Congenital Amaurosis (LCA), then the recent studies on gene therapies have been giving us a reason to hope.  LCA is a rare genetic condition that results in significant vision loss during childhood due to death of the photoreceptor rods and cones that detect and process light information.  There are several genetic variants of the disease, and one (LCA2) has been isolated to a mutation in the RPE65 gene.  Isolating a disease to one gene mutation makes for an exciting option: the ability to replace that gene into the body with gene therapy!

The RPE65 gene codes for a protein essential in the way the retinal pigment epithelium supports the photoreceptor rods and cones and uses vitamin A to detect light.  When the mutation was identified, LCA2 became a prime target for genetic therapy treatment because it required just one snippet of code to be replaced.  Scientists can use virus vectors to insert the correct RPE65 gene directly into the eye (via intravitreal injection), with the hopes that the treated person will begin making the corrected protein, and regain that lost visual function.  Some of the first studies from the University of Pennsylvania and University of Florida were published in 2009 and showed improvement in visual function.

Now a few years into these studies, new reports are coming in.  Gene replacement treatment in these patients has been safe, but it appears that the retinal photoreceptors have continued to degenerate despite the gene therapy.  OCT scans show retinal thinning occurring at the same rate in both treated and untreated eyes even years after original therapy.  It appears that gene therapy can improve vision for a period of time (how many years, we do not know), but the photoreceptors may still lose function long term.  Childhood treatment can help improve visual function but may not be enough to erase the damage during that early development. Early intervention appears to be key, but in humans LCA destruction is beginning even during development of the ocular tissue in the womb, so our capabilities for delivering this early treatment are limited.

Right now there are several Phase 3 clinical trials being run to assess long term benefit of RPE65 gene replacement therapy in LCA2, and the results look promising that vision can be improved at least temporarily.  To this point the published results have not shown any study participants suffering from vision loss, despite the progression to their retinal thinning, so it is too early to tell how long their visual improvements from gene therapy will last.  Trying to find a way to treat patients with gene therapy before they suffer retinal photoreceptor damage may be difficult, so scientists are looking at somehow combining gene therapy with other therapeutic treatment that may help stabilize retinal photoreceptor cells.  As of right now, no such medical treatment exists but eyes are on the use of LINGO-1 as a possible neuro-regenerator.  The science is new and innovative and sure to meet many hurdles along the way, but we are living in an exciting world of possibilities!

Eyewear styles have been having a true renaissance this year not just for women, but the men's ophthalmic and sunglass styles have also seen a ton of vintage updates.  For men's frames, 2014 is all about round, vintage detailing, and the metal mix.  If you focus on any one of these design aesthetics, you know that you are purchasing eyewear that will be leading men's fashion into 2015.  Here are some of the best men's fashion looks for the year:

The Clubmaster Trend:

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Mixed Media:  It's all about the mix of metals, leather, or even wood details

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Wood veneer glasses via

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Round:  Even if you stay basic with your materials, round frames update you into the biggest trend of 2014 and into the new year.

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There is no denying that the contact lens world is all about daily disposable lenses, and with CooperVision's recent acquisition of Sauflon, they added a new option to their growing line of single wear lenses.  The Clariti 1 Day lens (also called Fresh Day) is a silicone hydrogel single use lens that is available in spherical, astigmatism, and multifocal options.  This marks the first "family" of silicone hydrogel daily use lenses to be available from any company.

At a Glance (Clariti 1Day Spherical)

8.6 BC
14.1 mm Diameter
+8.00 to -10.00 power availability
86 Dk/t

What Makes This Lens Different

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Silicone hydrogel materials are the most breathable on the market, but they tend to have issues staying hyrdated for many people.  The Clariti 1 Day lens is formulated to offer that outstanding breathability that keeps eyes healthy, and also provide that all day comfort that contact lens wearers need.

Claiti 1 Day Dk/t (oxygen transmissibility):86

• By comparison CooperVision's other dailies have much lower oxygen transmission, with Proclear 1-Day coming in at 36.6 Dk/t and Clearsight 1-Day with 24 Dk/t

We know silicone hydrogel lenses offer superior oxygen levels to the corneal surface, but the hydrophobic (water repelling) silicone in the lenses can lead to end of day comfort and wetting issues.  The solution is Clariti's "AquaGen" technology that alters the silicone polymers into becoming hydrophilic.  This allows the tear film to better adhere to the surface of the lens and retain that natural moisture as the day progresses.

A more moisturized lens means a smoother surface for your eyelids as you blink across your contact lens throughout the day.  Typically lenses with lower coefficients of friction are considered to be more comfortable due to this blinking issue.  Graph from Sauflon

Other comfort perks include a a lower modulus lens material (a softer, more flexible feel to the lens) and higher water content than any other silicone hydrogel daily disposable lens on the market today (Dailies Total 1 and Acuvue TruEye).  The lens also boasts Class II UV blocking for added sun protection (98% of UVA and UVB rays blocked).

My Review

I have worn the Clariti 1 Day lens for one week now, and every time I put the lens in I am surprised by the initial comfort.  Upon insertion the lack of lens awareness is very comparable to the contact lens I typically wear, Dailies Total 1.  Comfort was very good until the end of the day for me, and I was able to get a good 14 to 16 hours of wear every day before I needed to take the lenses out.  Keep in mind that I am extremely sensitive about contact lens wear and I would expect the average wearer would be much less critical.  Am I turning in my Dailies Total 1 lenses?  Absolutely not.  But at this price tag (around $60 for a 90 pack), the Clariti 1 Day lens offers a very affordable alternative.  By comparison, a 90 pack of Dailies Total 1 retails for around $95 and a 90 pack for Acuvue TruEye retails for around $83.  CooperVision is planning to launch its own premium single use contact lens, MyDay, in 2015 in the States, and it considers that product to be the future rival to Dailies Total 1's premium lens dominance.

Take Home: A great lens for the price!  If you are experiencing dryness, redness, or comfort issues this lens is worth exploring.

Age Related Macular Degeneration with advanced central vision disruption image credit to eyedolatry.blogspot.com

Imagine a world where your central vision was nothing but a blur or distortion.  Any time you try look at something straight on, you can only see the periphery of the object you are trying to see.  Try recognizing faces or reading your cell phone or a book with nothing but peripheral vision.  This is what the world looks like for the millions of people worldwide that have advanced macular degeneration.  There is no cure for this devastating visual condition, but a new implantable telescopic device can help restore some of that central vision zone for the first time ever.

The CentraSight implantable telescope is made by VisionCare Ophthalmics, and is a vision enhancing device that can improve central vision range when placed inside the eye. Traditionally, patients with central vision loss had to rely on handheld or spectacle mounted telescopes to try to enhance their central vision. These devices were bulky and distracting, not to mention their limited visual potential (about 10 degrees of field is all they can provide!).  The CentraSight implantable telescope is just over 4 mm in size and sits discretely in the eye, making it less obvious to those around you that you are using a low vision device, and also freeing up your hands that would have otherwise had to hold the magnifying lens up to the eye whenever you wanted to use it.  Because the telescopic optics are inside your eye, there is the added benefit of a much larger observable field of view, between 20 and 24 degrees of gained central vision area is attainable with the implant/

Enlarged view of the CentraSight implantable telescope.  This is actually under 5 mm in size via

Implant inside the eye.  It is placed in the same place that a post-cataract surgery implant would traditionally be inserted via

Who Qualifies?
In October the FDA updated the candidacy needs for patients interested in the CentraSight implant to offer younger patients the opportunity to pursue the implant.  The new requirements are:

1) Bilateral Central Vision Loss due to Age Related Macular Degeneration

• If one eye is damaged with macular degeneration but the other still has great preserved central vision, then the patient is not a candidate.  The implant needs to be placed on the better seeing eye in order to provide of any improvement in perceived vision.  If the implant is put in the bad eye, then the brain will just suppress the bad eye's image and use the good eye only like it was doing before surgery.  You would have just had a very expensive surgery without any visual benefit.  In order for the telescope to work, your brain has to want to process its image, and that is why it must be placed on the eye with better vision to achieve the best effect.

Cleaning your glasses is just a normal part of your daily routine when you are a glasses wearer.  I know I have to clean mine 2-3 times a day due to the normal smudges and finger prints that my lenses will accumulate as I go through a normal work day.  But if you don't always have the right tools available, cleaning your glasses can not only be tedious but also expensive -- use a tissue or a harsh fabric, and  the scratches you create could mean you need to buy new lenses to see clearly again!  I always have a bottle of spray and lens cloth in my purse, but not everyone carries around a little Mary Poppins bag of wonders with them all day.  Enter the new Peeps cleaner from LensPen.

Peeps is a small hand held device that uses carbon to attract and remove the oils that can smudge and smear the surface of your lenses.  The other end of the product has a goat hair brush designed to prevent scratching to the delicate surface coatings of your glasses.  No spray or external cloths are needed -- the company recommends just breathing gently on the surface of your lens if a smudge persists and then slide the Peeps cleaner over them again in a circular motion.

The circular area is made to run over your lenses in a gentle, rotating motion, and utilizes carbon molecules to lift oils up and away.  The other end of the product has a goat hair brush to gentle remove surface debris. via

Pocket-sized so that you can keep them anywhere! via

The important thing to remember about your glasses is that the surface is very delicate.  Yes, you should have a scratch coating on your lenses to help prevent surface issues, but if you are using the wrong products no scratch coating in the world can withstand that kind of daily abuse.  Where the LensPen product prevails is that the carbon particles draw oils up and away from your lenses without relying on any rubbing or mechanical action.  It's all in the ionic attraction.  The goat hair brush on the other end are just there to gently remove any physical debris, but you aren't really rubbing your glasses clean with either side.  This type of product is designed to delicately protect your glasses lenses the same way you treat those expensive camera lenses.  The result should be clear, lasting lenses with no surface scratches!

Because the Peeps cleaner relies on an ionic charge attraction, there is a limit to how long it can last. Per the company's website, every time you close the Peeps cleaner back into its case it is recharged, up to 500 uses.

You can pick these up from Amazon for under $18.  Stocking stuffer for the glasses wearer in your life, perhaps?

Have you used the LensPen product?  If so, I would love to hear your personal reviews!

Seen the latest issue of Contact Lens Spectrum?  It was hard to miss that most of the articles were discussing study results about contact lens performance and where Ultra ranks against today's most popular lenses.  Bausch and Lomb's new monthly disposal Ultra contact lens has taken the market by storm since its full launch earlier this year, and there are plenty of things to like about the lens.  Here's a breakdown of the study results published in the CLS supplement.  Disclaimer: I want to add that the studies featured were all reported on by doctors with Bausch and Lomb and its parent company Valeant Pharmaceuticals.  I myself am not affiliated with any contact lens company or pharmaceutical company and am just presenting a summary of the findings from this report.  I have cited all tables included to their origin source of Contact Lens Spectrum, but at this time I have not found that they are available online.  I will update things here when they do become available for you to direct link to.

LogMAR units are used here to demonstrate visual clarity as perceived by the wearer.  20/20 is the perfect vision we all try to achieve during the eye exam and is shown above.  20/40 is legal driving vision.  Image from Contact Lens Spectrum Special Edition Volume 14, "Preventing Dehyrdation Blur"

Based on the study performed, image quality can vary greatly between blinks across different lens types.  30 seconds would be an incredibly long time to go without blinking, but many of us as computer users do go longer than 20 seconds without blinking, and you can see the blur that accompanies this. The Ultra lens in this simulation performs far and away better at keeping clarity even as the lens material is kept without moisture for 30 seconds. Image from Contact Lens Spectrum Special Edition Volume 14, "Preventing Dehyrdation Blur"