Pupil Stretching and IOL Implants

[Hoddy44]

I finally had a detailed session with Dr. Woodcock. I am 60 years old, a +7 farsighted, and have cataracts that qualify for removal based on glare.  The Dr. initial recommendation is a bilateral Restor which is different than his normal recommendation.  His recommendation seems to be based on ensuring that my reading vision is satisfactory given my high degree of farsightedness.  He will start with an implant in the non-dominant eye.  Of course, he has the flexibility of changing his lens decision for the second eye after seeing how the first eye does.  He also says that some Lasik and pupil stretching may be necessary a few months down the road.  What is pupil stretching and what does it accomplish?  Also, I'd like some more feedback from those who have had bilateral Restors and their satisfaction with it, including intermediate vision and halos?

[eyecu]

Definitely. That is why they were designated NTIOL. It has to do with contrast. In Tecnis studies by Pharmacia,there was a significant difference found between aspheric and spherical IOLs. In driving simulation studies, reaction time was imporved .5 seconds and 45 feet at 55 miles per hour. The mandated Dole 3rd brake light in new cars was only a .3 second increase in reaction time. As far as surgically induced aberrations, with a 5mm pupil, there were no induced changes over time at a 3 month post-op period. I think that is why some patients kick in and say something after about 3 months and others say something immediatley because they got through surgery with minimal changes. Ralph Chu,MD and Mark Packer,MD have the most experience with studies in this area and I believe the website in the article is by Ed Sarver who is an expert in optics and provides software for determining the right IOL model if you do not have one of the units mentioned in the article available. Technology will drive the market with these type of wavefront IOL's and presbyopic IOL's to strive toward better vision for all.

[JodieJ]

Re aspheric IOLs

I'm having doubts about the benefits of an aspheric vs. conventional IOL.  Recent studies suggest choosing an aspheric IOL based on a patient's pre-surgery spherical aberration measurement, with different ranges given for the 3 aspheric brands.  (A recent article in Review of Ophthalmology actually contains a link to a website which can determine spherical aberration based on pre-surgery topography measurements.)  This doesn't make a lot of sense to me, since cataract surgery and limbal relazing incisions will add an unknown amount of spherical aberration to the pre-surgery measurement.

In your experience, does an aspheric IOL enhance vision in a meaningful way for many people?  How meaningful is the reduction in intermediate/near visual acuity with an aspheric (vs. conventional) lens?  If it matters, the figures for my pupil size average 4.1 and 5.6.

[eyecu]

You have many good questions. The Tecnis is the original and the first. It corrects for corneal aberrations, the B&L for lenticular only. You will not have a full range of foucs. You can go with monovision with a little plus or plano in one eye and a little minus in the other but it can be hard to tolerate and you want to try it with contacts first. I tried it and could not do it. The ReZoom is going to give you great distance and intermediate but you have to get that 2nd zone in to pick up near and would need pupil stretching. The ReStor is going to give you great reading with a small pupil in bright light but not so good in dim light and poor intermediate. You need strecthing to bring in better distance. You have been very thorough. You have to talk to your doc or docs and make a decision and then mentally be postive to work it out. It does not happen over night with multifocals and takes time to adjust which you will have to commit to. Hard call. Doc can also change second eye based with different model based on how you do with the first eye. Yo really have to discuss your occupation or hobbies and deal with expectations. People on this board that have the lenses in their own eye are the best to get feedback from. Good luck!

[eyecu]

You are correct as far as working with lenses from a refractive standpoint can be an art. Pupil stretching can be performed at the time of surgery as well as post-op. It would be used to get the second ring in for the ReZoom and distance for the ReStor. The laser for a monofocal or multifocal would be used for astigmatism or for power correction if over minused. You can also perfrom LRI's for astigmatism. You just have to figure out what you want. A monofocal is going to give you great distance vision and you can wear readers for near. With a small pupil you might even pick up some depth of field for intermediate and he can always shoot for a little different outcome in the second eye based on the refraction of the first eye after three top four weeks post-op.

[JodieJ]

Please think twice before doing something that may not work well with your eyes.  Conventional IOLs can sometimes yield wonderful results.  One of my friends had a script similar to yours with mild astigmatism.  Before cataract surgery, his best corrected vision had never been better than 20/30.  Post-surgery he has 20/20 vision.  He only needs reading glasses for very small print; he can read menus and newspapers and use the computer without glasses, and I've seen a demo of each.  He doesn't have monovision (although this isn't a bad idea, either), but I suspect that his surgeon must have made one of his eyes a little nearsighted.  In any case, he's thrilled with his vision.

[eyecu]

Good luck on intermediate vision. You obvioulsy have a small pupil and are with an experienced doc to check it. With the ReZoom you would just be using the distance portion of the lens and would have to be stretched to 2.3mm to get that 2nd near zone in so you might as well go with a monofocal. They can also go with an argon laser pupiloplasty to enlarge it. With ReStor you will be using the central portion of the optic so you will pretty much be near with some depth of focus maybe due to the small pupil but will suffer on distance. That is why he might stretch the pupil.Maybe just a monofocal with readers would be best.Even Tecnis would not benefit you in dim light if your pupil does not dilate. Need more information on what it does under different lighting conditions.

[Ag-i-doc]

1.5mm is tiny.  for a multifocal design to work it would have to be bigger...

[Forum-OD-MP]

dont know about much about "pupil streaching".  as far as i know its used to make the pupil bigger during the extraction procedure so that the implant can be inserted.  it does not (that i know of) permanently change your pupil size.  i could be wrong.