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ANSWERED on Tue 18 Sep 2007 - 8:24 pm UTC by nancy

Question: Safety and Effectiveness of Crystalens, ReSTOR, ReZoom, and P-IOL for treatment of myopia

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 15 Sep 2007 23:08 UTCSat 15 Sep 2007 - 11:08 pm UTC 


I am researching options for vision correction surgery (other than LASIK or other corneal-shaping surgeries)  for moderate to severe myopia given my health history (see below).  Specifically, Crystalens, ReSTOR, ReZoom and Phakik Intraocular Lenses (P-IOL)

I realize this is a long posting but I am trying to be very clear in the type of information I need. I know I am asking for a lot of statistics and you may not be able to find all of it.  

If this is not priced appropriately please let me know what would be a more reasonable fee, or else let me know what research you would be able to provide to me for $100.

Thank you

Here is my health history:

• 42 year old female- Have not lost significant near vision yet

• Current refractive error:  -3.5 D in my right eye and -9.5 D in my left eye with slight astigmatism

• No cataracts

• Had PRK on right eye 12 years ago in 1995 (left eye has not been operated on). 

• As a result of PRK surgery in right eye, corneas are somewhat thinned and have been told by a surgeon I am not a good candidate for LASIK, at least not in my right eye.

• Both eyes tend to be dry, although I use artificial tears in the morning and this alleviates the problem

• Have been wearing aspherical disposable daily wear 2 week contacts for years but am growing intolerant of contacts due to Giant Papillary Conjunctivitis, which has not improved after treatment.  Am unwilling to switch to rigid gas permeable contacts but may try daily disposables until I get surgery

• Otherwise, eyes are healthy with no other known conditions

Here is the type of data I am looking for:

I would like data on risks and effectiveness on each of the procedures listed below based on as many large-scale studies or clinical trials you can find.   I define large scale to  be at least a few hundred patients in the study -the bigger the better.  (At the end of this document I have listed the data I already have so you do not duplicate what I have already found)
• Crystalens
• ReZoom
• Phakik Intraocular Lens (P-IOL) - 2 have been FDA approved:  Visian ICL and Artisan Verisyse

Note:  If you find data on other procedures that are not listed above for which I would be a good candidate, then I welcome you to include that data as well.

Specifically, for each of these procedures, here is the type of data I am looking for. 

• Number of patients in  study, and where and when study took place

• % of patients with post-surgery Uncorrected Visual Accuity (UCVA) of 20/20, 20/30, and 20/40 or better at near, intermediate, and far distances.

• If available, would like data broken down by age and pre-surgery refractive error

• If available, would like to know how many patients got Crystalens, ReSTOR, or ReZoom implants strictly to improve refractive error (referred to as Refractive Lens Exchange - RLE or Clear Lense Exchange) where patient does not have cataracts but simply wants to improve vision)

• Patient satisfaction data - how satisfied were patients after surgery?  What % of patients were able to be completely independent of glasses after the surgery?

• % of patients who reported unresolved complications 6 months after surgery including night-time vision problems such as glare, halos, starbursts,  etc

• % of patients who lost their vision or lost their eye as a result of any of the procedures

• Of P-IOL implants, what % and number of patients had retinal detachment and loss of corneal cells - how much over time?

• % of patients who had their lenses explanted, and of these, how many had a second lens implanted successfully

• % of patients who had other enhancement surgeries after their lens implantation such as LASIK, LASEK, piggyback P-IOL lenses, etc…to achieve better vision

Additional Questions:

Who are the top 10 (or more) opthalmologists in the US who have implanted:
• The most Crystalens implants
• The  most ReSTOR implants
• The most ReZoom implants
• The most P-IOL implants
Please provide the number of lenses implanted for each

Who are the top 10 (or more) opthalmologists in the Dallas area who have implanted:
• The most Crystalens implants
• The  most ReSTOR implants
• The most ReZoom implants
• The most P-IOL implants
Please provide the number of lenses implanted for each

What are the risks and complications of getting any one of the four types of lens implants in one eye only? (e.g. is there evidence that the brain has trouble adjusting to having one of these lenses implanted in one eye only, while using a soft contact lens in the other unoperated eye?)

What I do NOT want:
- Individual patient testimonials or anecdotes
- General information about the various lenses (I want the actual statistics of patients who have had it done from large scale studies or trials)
- Marketing claims by eyecare centers with no hard data to backup the claims
- Links to websites where the data I seek is so buried it will be difficult for me to sift through it to find my answers. 

Data I already have:
FDA Summary of Safety and Effectiveness Data on the following:
o Crystalens, FDA approved Nov.14, 2003
o ReSTOR, FDA approved March 21, 2005
o Artisan Verisyse - FDA approved Sept. 10,2004
o Visian ICL - FDA approved Dec. 22, 2005 - 526 eyes in 294 subjects

Thank you in advance for helping me.




 16 Sep 2007 03:55 UTCSun 16 Sep 2007 - 3:55 am UTC 

Hi Steph, and welcome to Uclue,

As you already suspect, I don't think it's possible to address every criterion you've set.

A researcher can certainly try to find every clinical study and medical journal report available that's most applicable to your situation, then summarize the major findings from each study.

I would suggest you post your "Additional Questions" as separate questions. See Uclue's Pricing Guidelines for more details on breaking up multi-part questions into smaller projects:

Please let us know if that sounds satisfactory.




 16 Sep 2007 04:32 UTCSun 16 Sep 2007 - 4:32 am UTC 

OK, that sounds reasonable.  Please disregard the 3 questions under the heading "Additional Questions".  Maybe I will post them as a separate question later.  However, please continue to take into consideration the info under the headings "What I do NOT want" and "Data I already have".

Yes, I would like a summary of the major findings from the studies and reports as they pertain to my questions (in layman's terms as much as possible).  Whatever amt of research that is reasonable for the fee I am able to pay at this time - $100.

Please advise me.... do I need to cancel this question, get a refund, and repost a new one with the Additional Questions deleted, or will this clarification suffice?

Thank you!


Uclue Admin 

 16 Sep 2007 13:04 UTCSun 16 Sep 2007 - 1:04 pm UTC 

Hi stephwebb,

There's no need to cancel and repost; your clarification will suffice (and is likely to make the question much more answerable).




 18 Sep 2007 20:24 UTCTue 18 Sep 2007 - 8:24 pm UTC 

Hi Steph,

I did the best I could with freely available studies, since many studies are registration only or fee-based and I can't summarize much information from those.

This is a general study on the effectiveness of RLE for myopia; it doesn't address specific brands.

"Refractive lens exchange in high myopia: long term follow up  ...
The aim of this follow up study was to establish the long term visual outcomes and incidence of complications following refractive lens exchange," from the British Journal of Ophthalmology, 2005:

Registration is required to read the whole article. From the Abstract:

"Operative and postoperative records of 62 cases of small incision phacoemulsification RLE performed in 37 patients over an 11 year period, by a single surgeon, were reviewed.  . . Two cases (3.2%) of retinal detachment occurred at intervals of 2 months and 5 months following uncomplicated RLE procedures.

"A posterior chamber intraocular lens was inserted in 46 eyes (74%). YAG laser posterior capsulotomy was performed in 38 of 62 eyes (61%) and did not represent a risk for retinal detachment.
"Conclusion: Refractive lens exchange results in rapid and predictable improvement in unaided vision in patients with high myopia. However, the risks of sight threatening complications inherent in any intraocular procedure underlie the need for appropriate patient selection."


Posterior chamber phakic intraocular lens for myopia of- 8 to- 19 diopters

"CONCLUSION: Posterior chamber phakic IOL implantation with the Staar Collamer plate lens is an effective and safe method for reducing or cor-
recting myopia between -8 and -19 D.

"Gains in spectacle-corrected visual acuity were common, and results suggested good refractive stability. Improvements in phakic IOL power calculation formulas are needed to improve the predictability of refractive outcome. [J Refract Surg 1998;14:294-305. . . [published by] Instituto Zaldivar, Mendoza, Argentina,
The authors have no proprietary interest in the materials presented."


I know you don't want to read through studies, but you may want to read this particular report so you can see the charts.

"Mixing Presbyopic IOLs: Studying the Studies. Some surgeons have been employing the strategy of mixing these lenses. Here are the results of their studies of this approach," by Walter Bethke, the Review of Ophthalmology, published in Vol. No: 14:01 Issue: January 2007:

Some surgeons are now mixing different brands of lenses.  Findings:

"glare and halos in 20 percent of ReZoom patients. ReZoom also is designed for reading with a relatively wide pupil, as would occur in dim light conditions."

"The ReSTOR lens . . . provides good near and distance acuity" but isn't that effective at "intermediate distances in some patients. In a study presented at the 2004 ASCRS meeting [it was reported] that, though all of 54 ReSTOR eyes could see 20/25 or better uncorrected at distance and J2 or better at near, some of them had their intermediate vision dip into the J4 range." ReSTOR isn't especially effective in dim light.

Crystalens is good for intermediate and long distance, and doesn't produce halos.

ReZoom requires "a pupil larger than 3 or 4 mm for patients to get the best near [vision] effect," so patients didn't do as well with ReZoom when it came to activities such as reading.

The results from mixing lenses:

From one study:  "the average uncorrected distance acuity was 20/20 in the ReSTOR/ReZoom and bilateral ReZoom groups, compared to 20/25 in the bilateral ReSTOR patients. Near vision was best in the bilateral ReSTOR group, J1.4, but the combined group was close at J1.5. . . Though 89 and 75 percent of the bilateral ReSTOR and ReZoom patients, respectively, were spectacle independent, none of the combined patients needed their glasses. . . The mix and match group had a little bit more halos, because the ReZoom causes a few more halos than ReSTOR.'

In another study: the doctor "compared the near and intermediate vision of 55 bilateral ReSTOR patients to that of 135 patients with combined ReZoom/ReSTOR implants." With data completed on 110 of those patients: "In the ReSTOR-only group, the average near acuity was J1, compared to J1.07 in the combined patients, yielding no statistically significant difference. At the intermediate range, though, the difference was clinically and statistically significant; the ReSTOR group (12-month follow-up) saw J3.81 and the combined patients (six-month follow-up) saw J2.39."

Surgeon Jay Pepose "took part in a prospective, multicenter study looking at the effects of combining the Crystalens with other IOLs. 'In this trial, we had 14 bilateral Crystalens patients, 12 bilateral ReSTOR, 12 bilateral ReZoom, six combined Crystalens/ReSTOR patients and three Crystalens/ReZoom patients,' says Dr. Pepose. 'What we found was, in the monocular data, the uncorrected vision at distance was about the same, ranging between 20/25 and 20/23. In terms of monocular best-corrected distance, the patients in the Crystalens group were better to a statistically significant degree, at 20/16.' "


Good Overview Articles for Laypeople:

From Eyenet:

"Focus On Clear Lens Exchange," by Lori Baker Schena, published Sept. '07:

"The Refractive Lens Exchange Debate," by Lori Baker Schena, published June 2005:

I hope this is of help to you,





 19 Sep 2007 00:24 UTCWed 19 Sep 2007 - 12:24 am UTC 


You'd said you didn't want to read through the articles and studies yourself. I just want you to know there are more studies available, but they are available only at registration sites or at a fee. (In some cases, the fee is as low as $4.95.)

I can't summarize data for you from these studies because they aren't available at free sites.

If you would like those resources, let me know, and I'll round up as many as I can and post them for you.





 19 Sep 2007 01:43 UTCWed 19 Sep 2007 - 1:43 am UTC 

Hi Nancy,
Thanks for your research and information.  I have only had time to skim through it today and look forward to delving in further in the next few days. You've found a lot of useful information.

I would definitely like to know where I can find those "register-only" studies.  A little extra spent on registration fees to get more unbiased data will be well worth it to me.  I don't mind reading through the study materials - I just need to know how to get to these.

These are the only two eyes I have and I want to make a good decision on what procedure to go with to improve my vision!

Thank you again,




 19 Sep 2007 03:40 UTCWed 19 Sep 2007 - 3:40 am UTC 

Since I last posted, I tried some different search strategies and found some more -- and I think more on-target -- information.

This time around I learned the Verisyse Phakic Intraocular Lens (PIOL) and the Visian Implantable Collamer Lens (IOL) appear to be the leading lenses for correcting myopia.
A Comparison of the ICL, STAAR Surgical and the Artisan/Verisyse phakic IOL. "Phakic lens options for myopia examined," from Eye World Magazine, August 2004:


From Graefe's Archive for Clinical and Experimental Ophthalmology," Volume 245, Number 1 / January, 2007, at Springerlink: "Correction of high myopia with different phakic anterior chamber intraocular lenses: ICARE angle-supported lens and Verisyse iris-claw lens"

From the abstract:
"Forty eyes were implanted with phakic IOLs . . . Twelve months after surgery, the mean refractive error (SE) was -0.19D (100% of eyes were within ±1.0D of the target refraction) in the ICARE group, and -0.86D (95% of eyes were within ±1.0D of the target refraction) in the Verisyse group. The postoperative refraction remained stable during the entire follow-up period . . . Efficacy and safety of surgery for both implanted lens models are very high."  No "statistically significant differences" between the two types of lenses were found.

The entire study can be read here:


"Implantable Contacts: Hope for Extreme Myopia," by Leanna Skarnulis, WebMD, March 2007:

This article discusses:

"The Verisyse Phakic Intraocular Lens (IOL) for people aged 21 and older
The Visian Implantable Collamer Lens (ICL) for people aged 21 to 45"

"Stanford University School of Medicine was one of 10 sites in the U.S. to evaluate implantable contacts.  Edward E. Manche, MD" says " 'The advantage of the Visian lens is that it's a small, foldable lens inserted through a small incision with one suture or no suture. The Verisyse lens requires a larger incision and longer recovery. Both work well.'"

"In clinical trials, both brands corrected vision well. With the Visian lens, 95% of patients had 20/40 or better vision, the level needed to obtain a driver's license, and 59% had 20/20 or better after three years. With the Verisyse lens, 92% had 20/40 or better vision, and 44% had 20/20 or better after three years."


"Refractive Surgery Today," from the University of Kentucky Healthcare site:

Compares Verisyse PIOL and Visian ICL (STAAR).
"The Verisyse® PIOL . . . placement within the eye is technologically difficult and it must attach to the midperipheral iris. This can result in disadvantageous and/or chronic inflammation. Its use is limited to pupil sizes of = 6.0 mm because of glare and halos. It is approved for -3.0 to 23.5 D myopia."
"The Visian® ICL (STAAR) is a foldable one-piece" has less risk of leakage, infection, trauma and astigmatism. . . . The Collamer in the Visian® ICL also reduces HOAs unlike the Verisyse® PIOL, thus enhancing the patient’s visual outcome. It is approved for myopia of -3.0 to -23.0 D. The Visian® ICL also fared better than the Verisyse® PIOL in FDA approval study data as 94% and 59% of Visian with eyes had postoperative vision of 20/40 or better and 20/20 or better respectively compared to 92% and 50% of Verisyse eyes respectively. Interestingly, the Visian ICL® compared favorably with LASIK in the treatment of moderate to high myopia (-8.0 to 12.0 D)." 


Visual Performance of AcrySof ReSTOR Apodized Diffractive IOL: A Prospective Comparative Trial, American Journal of Ophthalmology, Volume 141, Issue 5, May 2006, Page 827. (Patients can order the report for $4.95.)

You can read the abstract here:

"Twenty-five patients were assigned to the ReSTOR group and 15 patients to the monofocal group. . . . The AcrySof ReSTOR IOL provides a satisfactory full range of vision and achieves a more satisfactory quality of life when compared with the monofocal SA60AT IOL, but with lower contrast sensitivity."


From the EuroTimes, June 2007

"Diffractive apodised multifocal delivers high levels of spectacle independence"

Cataract "patients bilaterally implanted with the ReSTOR (Alcon) apodised diffractive IOL experience a full range of quality near, intermediate and distance vision and greatly
reduce their reliance on glasses, according to a number of recent studies presented during
the ESCRS [European Society of Cataract and Refractive Surgeons] Winter Refractive Meeting.

"96 patients got ReSTOR implants, "88 of which were bilateral implantations. Refractive results have been excellent . . . For distance visual acuity, 96 percent of patients said they never used glasses after the 60-day postoperative point.

"95% of patients were  'very satisfied,' and four percent said they were 'satisfied'. None of the patients requested an IOL exchange."

The youngest patient was 35 and "gained three lines of Snellen visual acuity in his right eye one month after baseline," as did a 59-year-old patient" in the left eye.

Hope this helps!





 11 Oct 2007 01:26 UTCThu 11 Oct 2007 - 1:26 am UTC 

Hi Nancy,

Thanks so much for your research.  You found lots of info I was looking for and gave me additional data that I hadn't even thought to ask about. I think I am going to hold off on the surgery for as long as possible to see if the surgery technology improves. 

I appreciate your hard work and look forward to asking more questions in the future!





 11 Oct 2007 15:30 UTCThu 11 Oct 2007 - 3:30 pm UTC 

Thanks. I'm glad I was able to help you.

I appreciate your decision to hold off on surgery for a while, as this appears to be fairly new area of medicine and is clearly still evolving.

I certainly wish you the very best when you do have a procedure.





 1 Dec 2007 14:02 UTCSat 1 Dec 2007 - 2:02 pm UTC 

Be carefull w/Crystalens. I just went to Bascom Palmer Miami and had it done.Bascom Palmer is suppose to be #1 nation wide.

I got the latest model. Well first 6 weeks 20/20, for distance buy it would not focuse to read. Now the lense moved forward (for reading) and got stuck there. So I am no longer 20/20 but also I have developed a rare glare that makes nigth dificult.

Changing the lense is very complicated and dificult...risky, not even the doctor will want to perform it.


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