Arysoft toric-Yellow??

Hello everyone.  My Dr. recommended Acrysoft Toric as a possible IOL option.  Is it actually yellow?  Is that color in any way shape or form detectable?   I don't want to have color variation as I like to take pictures....  Can someone who has this lens chime in?

Thanks, Liz

[JodieJ]

I have yellow AcrySof IQs, and the yellow tint makes no difference in my color perception.  The yellow is intrinsic to Alcon's blue-light filtration feature, which allegedly provides protection against age related macular degeneration.  (This alleged benefit seemed to me to be based on dubious evidence.)

I have seen a couple of posts on this site from people who believed that the yellow tint did affect their color perception.  Possibly, this is related to the power of the IOL implanted.  The yellow tint is much more intense in powers needed to correct very farsighted eyes; it's much less intense in the powers needed to correct eyes that are very nearsighted.  (I'm in the latter category.)    

[lotsoquestions4me]

Hmmmm..I'll need to research this a bit more, as I'm farsighted.  I think things appearing yellow would be a deal breaker.  Thanks for your response!

Anyone else with this lens?

Thanks!

[John C Hagan III, MD, FACS, FAAO]

Neither the medical literature nor my clinical experience with patients having that IOL have had any problems with yellowish tint to vision. It does not act like a tint on glasses.

Does protect the retina from UV light

JCH MD

[JodieJ]

Alcon claims that the yellow tint does not affect color perception.  However, they do make one ReStor model without the yellow tint.  In their advertising, this model is said to be appropriate for artists, photographers, certain craftsmen, etc.  Go figure.

Other considerations:  If you have significant astigmatism, the AcrySof toric IOL is supposed to be far superior to older toric IOLs, which had major rotation problems.  In addition, Alcon's advertising points out that someone with cataracts is already looking through lenses that are yellower than the yellowest power of an AcrySof IOL.  

[lotsoquestions4me]

Interesting.  My cataract is a posterior subcapsular cataract, so now things appear to have a white haze, not a yellow one--kind of like a fog or a mist rather than brownish.  Know what I mean?  So, I'd wonder if for me, being farsighted and with this type of cataract, I'd be able to see it.  Hmmmm....  I'll need to think about that.

Any other farsighted cataract folks with astigmatism out there?

Thanks so much for taking time with your responses--I really appreciate your experiences.

Liz

[sally987]

http://www.osnsupersite.com/view.aspx?rid=70622

This has a great article on the products used to make current and future iols.  It mentions the yellow alcon lens.  Article is from the Hawaiian Eye 2010 conference.  I hope you will be able to view it from this link.  (this article will probably be removed after a certain amount of time...and be replaced by another interesting article)

[sally987]

This is the cut and paste for the above article.  The photos of the iols did not come through:

OCULAR SURGERY NEWS EUROPE EDITION October 1, 2010
New-concept materials may widen choice of IOLs in near future
Hydrophilic and hydrophobic acrylic lenses as well as light-filtering silicone lenses offer promising options, a surgeon says.


New materials that are expandable, light-adjustable, thermodynamic and photochromic should increase the selection of IOLs within the next few years, according to a physician.

In the past, IOLs have been manufactured from acrylic or silicone materials. These two families of polymers encompass a wide variety of compounds, Liliana Werner, MD, PhD, director of preclinical research at the Berlin Eye Research Institute, Berlin, Germany, and associate professor at the University of Utah, Salt Lake City, USA, said in an interview with Ocular Surgery News.

“Though we have a general formula to represent the hydrogels [hydrophilic acrylics], each lens design is made of a different copolymer, with different water content, from 18% to 38%, and refractive index, from 1.46 to 1.48,” Dr. Werner said.


Hydrophilic acrylic
A new hydrogel compound, Acryfil CQ, is a proprietary copolymer hydrophilic acrylic with very high water content, at 73%, and a bonded UV absorber.

This is the material used in the Acqua lens (Mediphacos), a new-concept expandable IOL currently available in Brazil.


The Acqua (Mediphacos) expandable IOL is implanted in its dehydrated state and expands in the eye.
The XACT IOL (Advanced Vision Science) — Eternity (Santen) in Japan — is made of a glistening-free hydrophobic acrylic material with a high water content.








The thermodynamic SmartIOL (Medennium) is packaged as a solid rod that expands with body temperature. If compressed, it recovers full shape rapidly.



The dioptric power of the Calhoun Light Adjustable Lens is adjusted in the eye under UV light exposure.
The AcrySof Natural, with integrated yellow dye, filters blue light.



The SofPort AO with Violet Shield (Bausch + Lomb) provides a defense from violet light.
The optic of the Smart Yellow/Matrix Acrylic Aurium IOL (Medennium) changes from colorless to yellow upon exposure to UV light.
Images: Werner L

“The lens is delivered in its dehydrated state, with miniaturized dimensions. It goes through a very small incision and, once implanted in the watery capsular bag environment, it rehydrates, achieving its intended size, shape and optical power,” Dr. Werner said.

Capsular dyes should never be used in conjunction with this IOL because the material absorbs the color like a sponge. The lenses have had to be explanted in the few cases in which this occurred, she said.

Hydrophobic acrylics
Hydrophobic acrylics are another lens variety. Normally, hydrophobic acrylic lenses have very low water content, between 0.3% and 0.5%. However, there is one IOL, the XACT lens (Advanced Vision Science) sold as Eternity (Santen) in Japan, that is made of hydrophobic acrylic with 4% water content. The new material is licensed by Bausch + Lomb to be marketed outside Japan.

“This polymer is hydrated to equilibrium water content and then packaged in 0.9% saline solution. This special treatment makes the lens glistening-free, as proven by scientific studies,” Dr. Werner said.

Glistenings are fluid-filled microvacuoles that form within the optic when the IOL is in an aqueous environment. They are observed in all types of IOLs, but have been mainly associated with hydrophobic acrylic lenses.

The mechanism and causative factors of glistening formation have been investigated in several studies, and temperature changes seem to play a significant role.

“Water absorption rate of copolymers changes according to the temperature. If the lens is placed in warm water and the temperature is then lowered, the water inside the polymer becomes oversaturated. The water surplus gathers inside polymer voids, forming glistening,” Dr. Werner said.

The equilibrium water content that is achieved in the XACT IOL makes the material stable, although hydrated, it maintains hydrophobic characteristics.

Mentak and colleagues evaluated the effect of hydration on the hydrophobicity of different hydrophobic acrylic materials by measuring the contact angles.

Contact angles for dry IOLs and for IOLs hydrated at 37·C in balanced salt solution up to 28 days were measured. All dry IOLs were hydrophobic. Four-week hydration in balanced salt solution resulted in greater surface wetability for all IOLs.

“There was only a 3· drop in contact angle for the XACT IOLs and a much greater drop, from 16· to 24·, in the other lenses. In other words, the other lenses turned to a much greater hydrophilicity, with consequent changes in surface roughness and morphology,” Dr. Werner said.

The SmartIOL (Medennium) is another lens that changes its state inside the eye. It is made of a thermodynamic hydrophobic acrylic material, packaged as a solid rod. Body temperature turns the solid into a gel-like material within 30 seconds.

“The rod is 30 mm long and 2 mm wide. After implantation it turns into a 9.5-mm wide, 2- to 4-mm thick biconvex IOL. It is a very flexible lens: If compressed, it recovers full shape rapidly. This property gives to the SmartIOL great potential for accommodation,” Dr. Werner said.

The dioptric power and final dimensions of the lens are imprinted in the material before the rod is formed.

Light Adjustable Lens, light-filtering IOLs
Silicone has also shown great potential for innovative IOL concepts.

The Calhoun Light Adjustable Lens (LAL) is made of a silicone matrix polymer containing macromers and photoinitiators. These components allow the lens to absorb light and to undergo adjustable power changes.

“A drawback of this lens is the relatively large size, requiring a 3.5-mm incision,” Dr. Werner said.

In collaboration with Calhoun, Okihiro Nishi, MD, is currently working on an injectable material that fills the capsular bag and can be polymerized within it in one procedure.

IOLs with special blockers allow filtration of light, eliminating potentially dangerous wavelengths. The SN60AT AcrySof Natural (Alcon) has integrated yellow blue-light-filtering cromophores.

“Exposure to blue light is a contributor to AMD, according to some studies. The light transmittance of this lens mimics the protection provided by the pre-cataractous human crystalline lens,” Dr. Werner explained.

Other companies offer different options for protecting the retina, such as the SofPort AO IOL with Violet Shield by Bausch + Lomb.

“There are studies suggesting that blue light should not be blocked, as it is vital for scotopic vision, while UV radiation and violet light are phototoxic and provide negligible visual information,” she said.

The SmartYellow photochromic IOL, now Matrix Acrylic Aurium (Medennium), is made of a special hydrophobic acrylic material that is perfectly colorless when the patient is indoors, but upon exposure to UV light, the lens turns yellow.

“These technological advances seem very promising indeed. However, we should not forget that, for any new material, the assessment of long-term uveal and capsular biocompatibility is very important,” Dr. Werner said. – by Michela Cimberle