# Optical Forums > General Optics and Eyecare Discussion Forum >  Crizal Prevencia

## himmeroo

Anybody using the new crizal prevencia ? How's it working for you. What kind of price point are you using?

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## becc971

drink some more kool-aid himmerroo ;)

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## Uilleann

It's now available as far as I know, and is pricing the same as Sapphire.  We haven't run any yet, but have one of our docs interested in trying it out.  Time will tell.

We saw a sample in office yesterday, and as expected, it DOES in fact change the visual experience, in that it lowers the visible light entering the eye (granted, in a small bandwidth range near the purple end of things), but also causes a yellowing of apparent vision - exactly as I said all these A/R's would do.  In essence, it's an A/R, with a layer or two re-engineered to act as a flash purple mirror of sorts, while keeping the rest of the familiar greenish Crizal reflex color underneath.

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## wayway

Is this the same idea as Nikon's SeeCoat Blue? We've sold a few pairs, but the ex Japan 10 working day turnaround has killed it a bit for us.

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## edKENdance

I have it personally.  What Uilleann said is accurate.  It's essentially the same as the Hoya and Nikon equivalent.  Priced the same as Sapphire but we get 3-5 day turn around just like everything else.  People have pointed out  the cosmetics when I have them on so there seems to be some trade off for the health benefits compared to the cosmetic ones.

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## finefocus

> I have it personally. What Uilleann said is accurate. It's essentially the same as the Hoya and Nikon equivalent. Priced the same as Sapphire but we get 3-5 day turn around just like everything else. People have pointed out the cosmetics when I have them on so there seems to be some trade off for the health benefits compared to the cosmetic ones.


As I understand it, there are no substantial health benefits. There is HEV filtration, but not much, and not in a way better than a simple tint. The selling point is reduction of blue scatter from displays such as phones or tablets, and consequent increased contrast and reduced CVS.
This is comfort, not health.

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## edKENdance

> As I understand it, there are no substantial health benefits. There is HEV filtration, but not much, and not in a way better than a simple tint. The selling point is reduction of blue scatter from displays such as phones or tablets, and consequent increased contrast and reduced CVS.
> This is comfort, not health.


The information I've been presented with links the coatings with the prevention/diminishment of ARMD.

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## finefocus

> The information I've been presented with links the coatings with the prevention/diminishment of ARMD.


Yes, but to what degree? How much HEV is still transmitted after coating? In the case of the Hoya version, almost all of it. Do other versions filter more effectively?

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## edKENdance

Not sure about the other versions but E is marketing it specifically as a health product.

http://www.youtube.com/watch?v=MAmcrT8o9Fw

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## Uilleann

Because we need an expensive lens option - as we're all _too damn lazy_ to, Oh, I don't know....actually reach up and push a couple buttons to adjust the color of a display screen on our own.  LOL :Rolleyes:

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## edKENdance

> Because we need an expensive lens option - as we're all _too damn lazy_ to, Oh, I don't know....actually reach up and push a couple buttons to adjust the color of a display screen on our own.  LOL


m

But wouldn't it get boring if we had nothing new to talk about?

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## Reliable Optics

Not crazy about the residual color....

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## Uilleann

> Not crazy about the residual color....


Numerous reps have come in here, and almost all claimed that their super-secret brand of blue (really purple actually) absorbing fancy pants AR _DO NOT_ change the color of the lens.  I've been happy to tell them they're wrong each and every time.  There simply is _no_ way whatsoever to alter the visible spectrum of light as it passes through a medium, and _not_ have an altered color cast to a lens.

They all look like they've been swimming in the bottom of a urinal for a couple weeks to me.  Just like Trivex did (and several HI's too).

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## Robert Martellaro

It has to be somewhat yellow if the transmission to the eye is down *20%* between 415-455 nm. That's assuming there is a very good light seal around the eyes from a close fitting wrap frame. 

It might deserve a closer look for pseudophakia, although I'd strongly recommend additional protection from day/sunlight.

http://news.essilorusa.com/releases/...ble-nationwide

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## Eye Doc Chesapeake

Have sold approx 100 pairs so far.  Reflects most damaging wavelegths associated with lipofuscin accumulation in the RPE. Educating at risk patients is key along with samples to demo.  We retail at $140.  Hope this helps.  Best to all.


> Anybody using the new crizal prevencia ? How's it working for you. What kind of price point are you using?

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## petitesirah

Is anyone else having issues with crazing? We have only sold Prevencia once, to a patient wearing a single vision hi-index 1.60, and the coating crazed horribly within the first month... And has now done so again within a few months after having them redone. Our lab doesn't have any idea why this is happening and I'm hesitant to recommend the coating to our patients until we figure out what the problem is!

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## opty4062

Edged my first pair this week. The patient is high risk for AMD from the genetic test. She had no complaints of the slight residual color, so we will see how it goes. Ordered a "show and tell" pair for myself which should be in tomorrow or the next day. I'll let you know what I think as it goes. :)

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## uncut

> Anybody using the new crizal prevencia ? How's it working for you. What kind of price point are you using?



Unfortunately, one look at the sample plano that we glazed, and placed within our sample sets, and the "medicinal" appearance of the lens creates the same facial distortion as................................_.castor oil, on a teaspoon, under the nose of a four year old child!_

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## EyeManDan

I have despised 2 pair.  Both patients did their homework and came in for either SeeCoat Blue or Prevencia.  I see more benefit to the Prevencia then the SeeCoat blue.  I personally have the SeeCoat Blue on my own pair.  I do like the slight color contrast myself.

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## Plausible

> I have despised 2 pair. Both patients did their homework and came in for either SeeCoat Blue or Prevencia. I see more benefit to the Prevencia then the SeeCoat blue. I personally have the SeeCoat Blue on my own pair. I do like the slight color contrast myself.


Nothing better than informed consumers!!!!! If there was a "like it" botton I would press it!!!!!

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## optical24/7

> I have despised 2 pair.......  .


You hated them that much?

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## D_Zab

We've made a number of test pairs with Prevencia on them and we've gotten two general reactions; either a dislike for the yellowish color or purple hue, or a number of regular computer users noticing less eye fatigue after being on the computer all day. With the snowy winter we've had up here the purple reflection was terrible the second you step outside and it's also pretty bad under fluorescent lighting. It's not _as_ bad when it's sunny outside with less snow on the ground or indoors with incandescent lighting, but it's definitely still noticeable.

The general consensus among the people I've talked to about it say they would like it for intermediate/office glasses or if people spend a lot of time in front of the computer because of the reduced eye strain, but most would not prefer it on an everyday pair.

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## Uilleann

Wonder how many of those computer users would notice any difference whatsoever if you switched out the lenses for a regular A/R, told them it had the exact same benefit, and dispensed it at the same price?

Sticker shock induced placebo effect methinks?

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## edKENdance

> Wonder how many of those computer users would notice any difference whatsoever if you switched out the lenses for a regular A/R, told them it had the exact same benefit, and dispensed it at the same price?
> 
> Sticker shock induced placebo effect methinks?


They really don't cost that much more.  I had a weird one.  Lady bought glasses elsewhere and said they were turning her white kitchen a yellow colour.  Brought them in for me to have a look at and she was wearing Prevencia.  ECP sold it to her but didn't tell her anything about it.

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## EyeManDan

> You hated them that much?


dispensed and despised sometime go hand in hand

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## D_Zab

Funny story; we made the test pairs and somehow ended up with Alize on some of them. Those users originally said they didn't notice any difference for a month until someone pointed out to them that they didn't have any purple hue. After their pairs were corrected they reported less eye strain. It would appear to have passed the accidental placebo.

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## opty4062

I'm almost a week in my new prevencia lenses. My transitions don't seem to get as dark, but these are 7 compared to my older 6 pair. The purple cast doesn't bother me at all, but the slight yellow doesn't do my very fair complexion any favors. I can say, without a doubt they have helped my eye strain at the end of the day. My former q.i.d. tears habit is down to once a day and I have much less redness in the evening.
We are selling them at a more brisk pace than I expected. It certainly helps to be wearing them to show the patients what they look like. So far, so good.

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## merrymaker

I have a patient looking for a purple-hued AR coat but the blu-light tech is not requested or needed.  Any ideas that wouldn't have the yellowish-hue?

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## Nobody77

I only have experience with Hoya's BlueControl, so I will say this:

The coating's intention is NOT to filter 100% of blue light, why would it be? Lens would be bright Yellow. It does "cut" high energy light by around 11%. Now the "cut" of any light (incl. the Blue Light) is influenced by things like diopter value, lens index etc. But on any two compared Lenses the added value of BlueControl is around 11% more protection vs a classic AR coat, which for Hoya seems like the ideal ratio between "looks VS protection".

Of course the lens HAS to have a slight residual yellow color... Cause if you cut some blue from the light spectrum the result can not be white any more, but.... slightly yellow..

Best you can imagine this with some RBG mixer like this: http://www.colortools.net/color_mixer.html

If you boost all the RBG to 255, the result is white. Lower the Blue to like 220 and there you go (I use this to explain how these coatings work to Engineers and Teachers :p ... but nah, actually even ppl sensitive to colors working with graphics etc. should know this and decide after)

If not for the health benefits (quite many articles already floating around the web) the contrast benefits you can see right away (unless you work with someone who is a bit slower). 

Either way, here you can read something if interested, not saying it's the best links ever, but it's the ones I could find within a minute of using Google :)

http://www.crizalusa.com/SiteCollect...te%20Paper.pdf

http://www.revoptom.com/continuing_e...ssonid/109744/

http://metro.co.uk/2013/12/09/led-li...-eyes-4220937/

Hope this helps to understand the problematics a bit better :)

Cheers...

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## kittyeyes

Hey Opty4062-what's the genetic test for AMD your patient took. Did you administer it?

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## kittyeyes

Hi-what's the genetic test for AMD your patient did? Did you administer it?

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## opty4062

I and the head technician administer cheek swabs for the doctors that are shipped off to a lab via macular risk.  http://www.macularisk.com/
The results arrive in about a week. They show in a graph and numbers the likelyhood of a patient developing AMD over their lifetime. The testing includes lifestyle and family history questions as well.

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## chaoticneutral

I sold my firs pair in the office last month.  When it came in I was pretty disappointed.  Weird color and its not a clear lens.  There is a slight tint to it. We had our lab rep come in and I showed her the lenses.  She said that it was a "Niche" lens.  More often sold by the doctor to patients with early cataracts and macular degeneration.  It filters 20% of the harmful blue light and uv and then it sounded like every adult in the Charley Brown cartoons wahh wah wah waaaah wah waaaaaah. Were selling it for entirely to much but I can see the benefit for the "Niche" she's talking about.  I wouldn't sell it again. Ill leave that to the doctors to peddle.

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## Judy Canty

Any blue filtering lens product, either an infused tint or a HEV coating, is a good fit for computer users, gamers, etc.  Of course they're not clear, some tint is necessary to filter the blue wavelengths.  Think it through.

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## Chris Ryser

> *Any blue filtering lens product, either an infused tint or a HEV coating, is a good fit for computer users, gamers, etc. * *Of course they're not clear, some tint is necessary to filter the blue wavelengths.**  Think it through.
> *



Any lens measured through a real spectrometer will certify above statement.

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## Browman

> I sold my firs pair in the office last month.  When it came in I was pretty disappointed.  Weird color and its not a clear lens.  There is a slight tint to it. We had our lab rep come in and I showed her the lenses.  She said that it was a "Niche" lens.  More often sold by the doctor to patients with early cataracts and macular degeneration.  It filters 20% of the harmful blue light and uv and then it sounded like every adult in the Charley Brown cartoons wahh wah wah waaaah wah waaaaaah. Were selling it for entirely to much but I can see the benefit for the "Niche" she's talking about.  I wouldn't sell it again. Ill leave that to the doctors to peddle.


Considering that our televisions are now all LED backlit, and the average American spends untold hours a day on iPads, iPhones, or in front of computer monitors, a lens to filter out blue light doesn't seem that uncalled for.

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## Judy Canty

Just received my Blutech lenses today.  The color is not heinous, but it is noticeable.  That being said, the immediate effect at my computer is also noticeably more comfortable.

Waiting now for my BlueScreen AR with the same lens design for comparison.

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## Judy Canty

> Considering that our televisions are now all LED backlit, and the average American spends untold hours a day on iPads, iPhones, or in front of computer monitors, a lens to filter out blue light doesn't seem that uncalled for.


Agree.

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## Robert Martellaro

We could also turn the brightness down 20% or so, and maybe change the color temperature, but the peer reviewed (non-manufacturer sponsored) evidence is thin to nonexistent. 

I worry more about sun exposure, especially after cataract surgery.

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## Browman

> We could also turn the brightness down 20% or so, and maybe change the color temperature, but the peer reviewed (non-manufacturer sponsored) evidence is thin to nonexistent.


Have you any links? Most of the lit I've been able to look at has been manufacturer sponsored; about the only study I've found was from an experiment in Europe that found a link between HEV and eye damage, but that nominally involved specifically black light exposure and didn't look at LEDs, etc.

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## Judy Canty

http://www.ncbi.nlm.nih.gov/pubmed/15302349  and there are others.

Now, here's my take.  Back in the 70s-80s, we started talking about UV exposure and cataract formation.  There are still folks out there that believe it's a scam.  Most of us decided that the prudent step was to at least offer the option of UV protection. A generation later and UV absorptive lenses are the rule rather than the exception.  I believe that while the jury may still be out, to ignore or to choose to not offer the option of protection is less than prudent.  After all is said and done, it's your patient's vision and choice, not yours.

24 hours later, I am satisfied with my lenses.  My next pair will be the sun (outdoor) option since I prefer a brown polarized lens already.

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## Robert Martellaro

As I said- thin to nonexistent. 

Without reference to artificial light, I think...

Age-related Maculopathy and the Impact of Blue Light Hazard, 
ncbi.nlm.nih.gov/pubmed/16445433

Visible Light and Risk of Age-related Macular Degeneration, 
ncbi.nlm.nih.gov/pubmed/2095019

Sunlight and the 10-year Incidence of Age-related Maculopathy: the Beaver Dam Eye Study, 
ncbi.nlm.nih.gov/pubmed/15136324

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## Judy Canty

Why a concern about sun exposure following cataract surgery?  IOL's are UV-absorptive, some are even blue-light absorptive as well.

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## Robert Martellaro

> Why a concern about sun exposure following cataract surgery?  IOL's are UV-absorptive, some are even blue-light absorptive as well.


I've observed that most folks are more light sensitive following cataract surgery. The simplest explanation is due to increased (x2 or more) retinal illumination from the clearer media. Most will start to wear sunglasses for this reason, if they haven't been wearing tinted lenses heretofore. Are there any retinal health benefits? 

Here are some starting points; if I have time I'll post more.

http://www.aao.org/publications/eyen...cfm#__topdoc__

http://www.revophth.com/content/d/re.../1310/c/25230/

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## Judy Canty

I would argue that there is a difference between light sensitivity and either UV or HEVL (Blue Light) exposure.  Neither am I trying to argue in favor of one lens treatment versus another.  I would posit that the environment in which we now function has changed dramatically in a very short amount of time and that it would be unwise to further assume that our patient's vision will remain unaffected, keeping in mind that generations of Chesapeake Bay watermen were exposed to excessive amounts of UV rays before a link to cataracts was established.  To ignore the possibility of cumulative damage from high energy visible light seems, to me, to be disingenuous. 

But, to each his own.

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## Chris Ryser

*Cataracts and Other Eye Damage*

Cataracts are a form of eye damage in which a loss of transparency in the lens of the eye clouds vision. If left untreated, cataracts can lead to blindness. Research has shown that UV radiation increases the likelihood of certain cataracts. Although curable with modern eye surgery, cataracts diminish the eyesight of millions of Americans and cost billions of dollars in medical care each year.
Other kinds of eye damage include pterygium (tissue growth that can block vision), skin cancer around the eyes, and degeneration of the macula (the part of the retina where visual perception is most acute). All of these problems can be lessened with proper eye protection. Look for sunglasses, glasses or contact lenses if you wear them, that offer 99 to 100 percent UV protection.

see all of it ------------>  http://www2.epa.gov/sunwise/health-effects-uv-radiation

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## Robert Martellaro

> I would argue that there is a difference between light sensitivity and either UV or HEVL (Blue Light) exposure.


Yes, two different issues. However, post cataract surgery eyes do not have the benefit of a clouded and/or yellow media.




> Neither am I trying to argue in favor of one lens treatment versus another.  I would posit that the environment in which we now function has changed dramatically in a very short amount of time


Office workers since the 50's have been exposed to fluorescent lighting.  




> and that it would be unwise to further assume that our patient's vision will remain unaffected, keeping in mind that generations of Chesapeake Bay watermen were exposed to excessive amounts of UV rays before a link to cataracts was established.  To ignore the possibility of cumulative damage from high energy visible light seems, to me, to be disingenuous. 
> 
> But, to each his own.


It should be studied, if there is evidence to suspect that artificial lighting is a danger to our eyes. However, I have had no success finding peer reviewed scientific studies to date, only conjecture. And because the luminance levels indoors are _significantly_ lower than what we receive from sunlight, I suspect that the old saying 'the dose makes the poison' may be relevant.  

*Retinal Light Toxicity*

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3144654/

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## Judy Canty

If only fluorescent lighting were the only source.  Few, if any, were working with computer screens, smart phones, etc.  The problem is that the jury is still out.  I'm sure that a few generations of watermen would have benefited from UV protection, had we only known its effects earlier.

An ounce of protection, just in case there's no cure?  I will hold fast to offering the option rather than waiting for the question or the demand.

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## Joe Zewe

We began offering the lenses to deflect/absorb HEV light in our Chemistrie system and also as a ready-made product.  We looked at different lenses and coatings for several months and decided to offer both yellow tinted lenses and clear lenses with the AR coating that deflects the blue light.  We are selling more of the clear lenses due to cosmetic reasons.  Customers seem to prefer the clear lenses with a slight blue hue to the yellow/amber lenses.  

I try to avoid the debate regarding blue light and AMD.  Only time will tell if there is a link.  As someone who has spent much of his career looking at a computer screen, HEV lights is a concern. Like Robert notes, many of the studies were sponsored by lens companies.  What I do believe is that glasses that deflect blue light make for a much better experience when you spend time in front of a computer screen and the customer feedback we have to date confirms this.  

We had a booth back in January at the Consumer Electronics Show to see if the tech world would embrace a product such as this.  The feedback was overwhelmingly positive.  A high % of people who work in front of a computer experience digital eyestrain.  When you explain and demonstrate the product to a consumer spends a significant amount of time in front of a PC or other digital device, a very high % will make the purchase.  

In Japan, there is an optical retailer named Jins.  This company introduced a line of computer glasses a few years back that has sold in the millions of units.  They are offered in both Rx and ready made.  Sales of these glasses have slowed somewhat, but they are still a big seller.  

In my biased opinion, the debate needs to get beyond whether or not you want to carry a PC lens product but rather which one will you carry.  Independents need to establish themselves as the experts and the goto place for such products before they end up on endcaps at CVS, Walmart and Costco.

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## MakeOptics

> http://www.ncbi.nlm.nih.gov/pubmed/15302349  and there are others.
> 
> Now, here's my take.  Back in the 70s-80s, we started talking about UV exposure and cataract formation.  There are still folks out there that believe it's a scam.  Most of us decided that the prudent step was to at least offer the option of UV protection. A generation later and UV absorptive lenses are the rule rather than the exception.  I believe that while the jury may still be out, to ignore or to choose to not offer the option of protection is less than prudent.  After all is said and done, it's your patient's vision and choice, not yours.
> 
> 24 hours later, I am satisfied with my lenses.  My next pair will be the sun (outdoor) option since I prefer a brown polarized lens already.


Earliest I have been able to find:

What's in a Color? The Unique Human Health Effects of Blue Light
Holzman DC 2010. What's in a Color? The Unique Human Health Effects of Blue Light. 
Environ Health Perspect 118:A22-A27. doi:10.1289/ehp.118-a22


More Research:

Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration in Humans
Joshua J. Gooley, Kyle Chamberlain, Kurt A. Smith, Sat Bir S. Khalsa, Shantha M. W. Rajaratnam, Eliza Van Reen, Jamie M. Zeitzer, Charles A. Czeisler, Steven W. Lockley
J Clin Endocrinol Metab. 2011 March; 96(3): E463âE472. Published online 2010 December 30. doi: 10.1210/jc.2010-2098


The human circadian system adapts to prior photic history
Anne-Marie Chang, Frank A J L Scheer, Charles A Czeisler
J Physiol. 2011 March 1; 589(Pt 5): 1095â1102. Published online 2011 January 10. doi: 10.1113/jphysiol.2010.201194
PMCID:  PMC3060589


High sensitivity of the human circadian melatonin rhythm to resetting by short wavelength light.
Lockley SW, Brainard GC, Czeisler CA.
J Clin Endocrinol Metab. 2003 Sep;88(9):4502-5.
PMID: 12970330 [PubMed - indexed for MEDLINE]


Effect of Light on Human Circadian Physiology
Jeanne F. Duffy, Charles A. Czeisler. Sleep Med Clin. Author manuscript; available in PMC 2010 June 1.
Published in final edited form as: Sleep Med Clin. 2009 June; 4(2): 165â177. doi: 10.1016/j.jsmc.2009.01.004
PMCID:  PMC2717723


Suppression of melatonin secretion in some blind patients by exposure to bright light.
Czeisler CA, Shanahan TL, Klerman EB, Martens H, Brotman DJ, Emens JS, Klein T, Rizzo JF 3rd.
N Engl J Med. 1995 Jan 5;332(1):6-11.
PMID: 7990870 [PubMed - indexed for MEDLINE]


A phase response curve to single bright light pulses in human subjects
Sat Bir S Khalsa, Megan E Jewett, Christian Cajochen, Charles A Czeisler
J Physiol. 2003 June 15; 549(Pt 3): 945â952. Published online 2003 April 25. doi: 10.1113/jphysiol.2003.040477
PMCID:  PMC2342968


Amplitude Reduction and Phase Shifts of Melatonin, Cortisol and Other Circadian Rhythms after a Gradual Advance of Sleep and Light Exposure in Humans
Derk-Jan Dijk, Jeanne F. Duffy, Edward J. Silva, Theresa L. Shanahan, Diane B. Boivin, Charles A. Czeisler
PLoS One. 2012; 7(2): e30037. Published online 2012 February 17. doi: 10.1371/journal.pone.0030037


Sex difference in the near-24-hour intrinsic period of the human circadian timing system
Jeanne F. Duffy, Sean W. Cain, Anne-Marie Chang, Andrew J. K. Phillips, Mirjam Y. MÃ¼nch, Claude Gronfier, James K. Wyatt, Derk-Jan Dijk, Kenneth P. Wright, Jr., Charles A. Czeisler
Proc Natl Acad Sci U S A. 2011 September 13; 108(Supplement_3): 15602â15608. Published online 2011 May 2. doi: 10.1073/pnas.1010666108


Uncovering Residual Effects of Chronic Sleep Loss on Human Performance
Daniel A. Cohen, Wei Wang, James K. Wyatt, Richard E. Kronauer, Derk-Jan Dijk, Charles A. Czeisler, Elizabeth B. Klerman
Sci Transl Med. Author manuscript; available in PMC 2010 July 13. Published in final edited form as: Sci Transl Med. 2010 January 13; 2(14): 14ra3. doi: 10.1126/scitranslmed.3000458
PMCID:  PMC2892834


The Impact of Sleep Timing and Bright Light Exposure on Attentional Impairment during Night Work
Nayantara Santhi, Daniel Aeschbach, Todd S. Horowitz, Charles A. Czeisler
J Biol Rhythms. Author manuscript; available in PMC 2009 August 1.
Published in final edited form as: J Biol Rhythms. 2008 August; 23(4): 341â352. doi: 10.1177/0748730408319863
PMCID: PMC2574505


Short-Wavelength Light Sensitivity of Circadian, Pupillary, and Visual Awareness in Humans Lacking an Outer Retina
Farhan H. Zaidi, Joseph T. Hull, Stuart N. Peirson, Katharina Wulff, Daniel Aeschbach, Joshua J. Gooley, George C. Brainard, Kevin Gregory-Evans, Joseph F. Rizzo, III, Charles A. Czeisler, Russell G. Foster, Merrick J. Moseley, Steven W. Lockley. 
Curr Biol. 2007 December 18; 17(24): 2122â2128. doi: 10.1016/j.cub.2007.11.034
PMCID:  PMC2151130


Entrainment of the human circadian pacemaker to longer-than-24-h days
Claude Gronfier, Kenneth P. Wright, Jr., Richard E. Kronauer, Charles A. Czeisler
Proc Natl Acad Sci U S A. 2007 May 22; 104(21): 9081â9086. Published online 2007 May 14. doi: 10.1073/pnas.0702835104
PMCID:  PMC1885631


Decreased sensitivity to phase-delaying effects of moderate intensity light in older subjects
Jeanne F. Duffy, Jamie M. Zeitzer, Charles A. Czeisler
Neurobiol Aging. Author manuscript; available in PMC 2008 May 1.
Published in final edited form as: Neurobiol Aging. 2007 May; 28(5): 799â807. Published online 2006 April 18. doi: 10.1016/j.neurobiolaging.2006.03.005
PMCID:  PMC1855248


Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans
Claude Gronfier, Kenneth P. Wright, Richard E. Kronauer, Megan E. Jewett, Charles A. Czeisler
Am J Physiol Endocrinol Metab. Author manuscript; available in PMC 2009 October 14.
Published in final edited form as: Am J Physiol Endocrinol Metab. 2004 July; 287(1): E174âE181. Published online 2004 March 23. doi: 10.1152/ajpendo.00385.2003
PMCID:  PMC2761596


Intrinsic period and light intensity determine the phase relationship between melatonin and sleep in humans
Kenneth P. Wright, Claude Gronfier, Jeanne F. Duffy, Charles A. Czeisler
J Biol Rhythms. Author manuscript; available in PMC 2009 July 27.
Published in final edited form as: J Biol Rhythms. 2005 April; 20(2): 168â177. doi: 10.1177/0748730404274265
PMCID:  PMC2714089


Sensitivity of the human circadian pacemaker to nocturnal light: melatonin phase resetting and suppression
Jamie M Zeitzer, Derk-Jan Dijk, Richard E Kronauer, Emery N Brown, Charles A Czeisler
J Physiol. 2000 August 1; 526(Pt 3): 695â702. doi: 10.1111/j.1469-7793.2000.00695.x
PMCID:  PMC2270041


Intrinsic near-24-h pacemaker period determines limits of circadian entrainment to a weak synchronizer in humans
Kenneth P. Wright, Jr., Rod J Hughes, Richard E. Kronauer, Derk-Jan Dijk, Charles A. Czeisler
Proc Natl Acad Sci U S A. 2001 November 20; 98(24): 14027â14032. doi: 10.1073/pnas.201530198
PMCID:  PMC61161


Phase-shifting human circadian rhythms: influence of sleep timing, social contact and light exposure
J F Duffy, R E Kronauer, C A Czeisler
J Physiol. 1996 August 15; 495(Pt 1): 289â297.
PMCID:  PMC1160744


Temporal dynamics of late-night photic stimulation of the human circadian timing system
Zeitzer JM, Khalsa SB, Boivin DB, Duffy JF, Shanahan TL, Kronauer RE, Czeisler CA.
Am J Physiol Regul Integr Comp Physiol. 2005 Sep;289(3):R839-44. Epub 2005 May 12.
PMID: 15890792 [PubMed - indexed for MEDLINE]


Adaptation of human pineal melatonin suppression by recent photic history
Smith KA, Schoen MW, Czeisler CA.
J Clin Endocrinol Metab. 2004 Jul;89(7):3610-4. Erratum in: J Clin Endocrinol Metab. 2005 Mar;90(3):1370.
PMID: 15240654 [PubMed - indexed for MEDLINE]


Dynamic resetting of the human circadian pacemaker by intermittent bright light.
Rimmer DW, Boivin DB, Shanahan TL, Kronauer RE, Duffy JF, Czeisler CA.
Am J Physiol Regul Integr Comp Physiol. 2000 Nov;279(5):R1574-9.
PMID: 11049838 [PubMed - indexed for MEDLINE]


Human circadian pacemaker is sensitive to light throughout subjective day without evidence of transients.
Jewett ME, Rimmer DW, Duffy JF, Klerman EB, Kronauer RE, Czeisler CA.
Am J Physiol. 1997 Nov;273(5 Pt 2):R1800-9.
PMID: 9374826 [PubMed - indexed for MEDLINE]


Exposure to bright light and darkness to treat physiologic maladaptation to night work.
Czeisler CA, Johnson MP, Duffy JF, Brown EN, Ronda JM, Kronauer RE.
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I have full versions and copies for anyone interested but I hate posting my research because I seem to always find an article about it in next months optical rags.  Using someone elses time an effort to research a subject is not FREE for anyone being paid to write articles unless they either credit or link back IMO, but since asked and I had it handy.

If interested you could also search for f.lux which is software that will change your monitors color temperature to match the suns color temperature throughout the day.  I recommend it to all my clients that suffer from sleep deprivation and have jobs working on computers.

Can't wait until next months issue of 20/20, ECP Mag, etc. where the resident expert all of a sudden has these great ideas for blue light.

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## Robert Martellaro

If anyone starts a thread on human circadian rhythms and light exposure, you're the man!

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## obxeyeguy

> If anyone starts a thread on human circadian rhythms and light exposure, you're the man!


I have actually made a pair of lenses to do just that.  A very interesting experience, and yes, it worked.

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## Robert Martellaro

> I have actually made a pair of lenses to do just that.  A very interesting experience, and yes, it worked.


My clients tell me they've had success with light therapy and SAD. How do eyeglasses fit in?

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## obxeyeguy

> My clients tell me they've had success with light therapy and SAD. How do eyeglasses fit in?


Not to hi-jack here, but had a fairly intelligent customer with sleep problems.  Customer is a big time internet researcher, and brought me all this info on high contrast light filtering, not at the office for my notes but, I believe it was filtering in the 540 to 580 range.  They were to be worn a couple hours before normal sleep time to change the circadian clock to normal.  Patient reported back after about 2 weeks, things were better.  Haven't had another chance to prove or disprove this theory, but I do have a happy patient.

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## MakeOptics

> Not to hi-jack here, but had a fairly intelligent customer with sleep problems.  Customer is a big time internet researcher, and brought me all this info on high contrast light filtering, not at the office for my notes but, I believe it was filtering in the 540 to 580 range.  They were to be worn a couple hours before normal sleep time to change the circadian clock to normal.  Patient reported back after about 2 weeks, things were better.  Haven't had another chance to prove or disprove this theory, but I do have a happy patient.


I have full spectrum light bulbs in our bedroom that turn on 1/2 hour before I wake.  Its refreshing, light is life light is composed of energy our body needs that energy.  Pretty simple stuff.

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## Judy Canty

Your ability to regurgitate web content is impressive, but it is hardly YOUR research.  I am as capable as anyone of finding the information I use for my writing.  However, thanks for the offer, but I believe I'll pass.  On the other hand, perhaps you were referring to other members who write for various trade mags.  Thinly veiled insults were never your forte, MO.




> Earliest I have been able to find:
> 
> What's in a Color? The Unique Human Health Effects of Blue Light
> Holzman DC 2010. What's in a Color? The Unique Human Health Effects of Blue Light. 
> Environ Health Perspect 118:A22-A27. doi:10.1289/ehp.118-a22
> 
> 
> More Research:
> 
> ...

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## MakeOptics

> Your ability to regurgitate web content is impressive, but it is hardly YOUR research.  I am as capable as anyone of finding the information I use for my writing.  However, thanks for the offer, but I believe I'll pass.  On the other hand, perhaps you were referring to other members who write for various trade mags.  Thinly veiled insults were never your forte, MO.


I wasn't insinuating you.  Yes you are right regurgitating web information is easy, when Crizal Prevenzia came out I spent a few weeks putting together a bunch of information.  That software which I plainly stated in my post and the links it provides was the easy part.  

I have learned to reserve the meat of my knowledge because of this very scenario, sharing instead of being appreciated is just plain loathed among opticians.  I find that the dumber I appear the more accepted I am at least until the grey hairs fill in, until then I'll just absorb and continue not to share.

BTW, I believe Dr Carlock is writing on UV/HEV light in one of the coming issue of your magazine and I have shared this information with her months ago, the choice to pass unfortunately is not yours in this case.

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## MakeOptics

I can see how maybe you could have taken offense to my earlier post.  I quoted your post because Roberts follow-up post referenced little available information.  My reply backed up your own assertions about UV and HEV, with actual research and data.  And No thinly veiled insults are not my forte, I speak my mind another method which allows me to sleep at night.

Sorry if somehow my post was misconstrued as an insult.

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## Robert Martellaro

> I can see how maybe you could have taken offense to my earlier post.  I quoted your post because Roberts follow-up post referenced little available information.


Quality, not quantity, and *on-topic*.

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## MakeOptics

> Quality, not quantity, and *on-topic*.


Your right on topic but the quality of the research in my post is high.

I think its the application of a new product and by new the stack has been rearranged.  For now the uv reflectance of the ARC is being touted as the holy grail for outdoor use but I think the real application is as a therapuetic tint.  In a therapeutic application it can be used to help with sleep disorders.

There is a lot of research that deals with dyslexia and filters, low vision and filters, etc.  I used to enjoy post from a professional from across the pond that dealt with filters and their therapeutic effects.  I think the future will hold various filters and hopefully we can see studies on the effects of different wavelengths of light.

If you are interested in some phenominal applications of filters call BPI and inquire about their 4-5-6 lenses.  If you pm me Robert we can talk in more detail.

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## suzicoleman

<<They all look like they've been swimming in the bottom of a urinal for a couple weeks to me. Just like Trivex did (and several HI's too).>>

I have to agree. After seeing the results on a 1.74 HiX lens, one of my patients couldn't even wear it because the yellow was so distracting. I won't sell it on HiX again.

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## nokato

I wear the Hoya recharge, Yes it does have a funny yellowish color, and the AR itself is blue, but my eyes don't seem as tired at the end of the day compared to my regular AR coated lenses.  A co-worker in the hospital feels the same way, that her eyes just are not as tired.

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## Uilleann

It's like blueblockers all over again.  ;)  So much anecdotal "evidence" of the efficacy of the "latest" trend in eye glasses.  What's old is new again.  LOL

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## Fezz

> It's like blueblockers all over again.  ;)  So much anecdotal "evidence" of the efficacy of the "latest" trend in eye glasses.  What's old is new again.  LOL


You better calm down Skippy!

Captain  Obvious, aka The King of Cut and Paste, will spank your experience, knowledge, and educated wisdom, on this subject and let you know that 52 years ago, in a European country, his family invented a tint that was Blueishblockerish in nature, that has proven to be able to save the human race! 

Don't make him cut-n-paste to prove it!

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## Paul Smith LDO

Really?! His family invented the blueish blockerish tinty thingy.  I, for one, need to hear more about this.  So I will kick back with a jar of delicious paste, some cold beer to wash it down with and keep an eye out for blood on the screen from paper cuts.

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## Uilleann

> You better calm down Skippy!
> 
> Captain  Obvious, aka The King of Cut and Paste, will spank your experience, knowledge, and educated wisdom, on this subject and let you know that 52 years ago, in a European country, his family invented a tint that was Blueishblockerish in nature, that has proven to be able to save the human race! 
> 
> Don't make him cut-n-paste to prove it!


OK.  Yeah...I giggled.






;)

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## mdeimler

Wow, tough crowd in here...

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## sharpstick777

> Any blue filtering lens product, either an infused tint or a HEV coating, is a good fit for computer users, gamers, etc.  Of course they're not clear, some tint is necessary to filter the blue wavelengths.  Think it through.


Judy, there is a new product that will filter Blue Light via the material, not in a coating.  It uses EMR interference and not particle occlusion, so a EM field is created that blocks certain spectrums, very much like some UV technologies (from what they would actually share with me).   It will block about 80% of Blue with less than .5% residual color when finished (semi-finished blanks do show some residual color).  PM me for more info...  unlike other solutions that block only 20% Blue but have 10% residual color.

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## Sledzinator

> Judy, there is a new product that will filter Blue Light via the material, not in a coating.  It uses EMR interference and not particle occlusion, so a EM field is created that blocks certain spectrums, very much like some UV technologies (from what they would actually share with me).   It will block about 80% of Blue with less than .5% residual color when finished (semi-finished blanks do show some residual color).  PM me for more info...  unlike other solutions that block only 20% Blue but have 10% residual color.


Is this from Misui? Have you seen or do you have any pictures?

http://www.visionmonday.com/technolo...elength-light/

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