This article is more than 5 years old. Information may no longer be current.
Multifocal implants another option for hyperopic presbyopes
Guest writer explains the nuances of multifocal IOLs to complement blended vision implants.
Click Here to Manage Email Alerts
We have been discussing various lens-based procedures for the correction of presbyopia. Last month I outlined the details of the blended vision lens implant approach, which relies heavily on the as-yet unexplained property of IOL pseudoaccommodation to minimize the degree of interocular difference needed to address full presbyopia. This is the reason that blended vision implants have proved much more successful than monovision contact lenses.
Blended vision implants have worked so well for me over the years that I have been very reluctant to use any other approach to presbyopia — including multifocal implants. My longtime friend and co-faculty member Dr. Bruce Wallace has finally convinced me that I need to become more familiar with the nuances of the Array multifocal (Advanced Medical Optics) to complement blended vision implants. But Bruce’s insistence is not the only reason I am ready. I have been receiving an astonishing number of e-mails in response to this series of columns in Ocular Surgery News, many from patients who read the OSN SuperSite regularly, such as this one:
Dr. Maloney,
Thank you for writing such an informative OSN article. I had PRELEX surgery … over 3 years ago … my regained ability to effortlessly read all day without glasses and to easily follow a golf ball made me feel like a young woman again. As far as halos, they are no worse than they were with my contacts, and I no longer have those pesky dry red eyes that I developed from wearing contacts from age 43 to 57.
So Bruce will be my mentor as I start with multifocals. I do not know of anyone who knows more about the nuances of this approach with more credibility in our profession. As you read his column on multifocal implants, I think you will see that Bruce understands the crucial difference between science and salesmanship. If you too are persuaded to begin with this approach, I recommend the text “Refractive Cataract Surgery and Multifocal IOLs,” which Bruce edited and is published by SLACK Incorporated (publisher of Ocular Surgery News). I will keep you informed of my early experience with the Array in future columns.
by R. Bruce Wallace III, MD
OSN ASCs SECTION EDITOR
There are many of us who agree with Dr. Bill Maloney: Lens-based refractive surgery is the next logical step in our quest to help patients reduce their need for glasses. I predict that the first segment of the population to undergo these procedures will be unhappy hyperopic presbyopes with some degree of lens changes. Corneal-based refractive surgery such as LASIK remains an attractive modality to correct myopia. On the other hand, correcting hyperopia and presbyopia with LASIK has not enjoyed the same level of success. Now with custom corneal ablation, we are attempting to erase aberrations that many times are lenticular and progressive moving targets. Why not get rid of the source of these mounting aberrations with lens surgery? Treatments with other corneal reshaping procedures such as conductive keratoplasty can create various levels of monovision or blended vision and can make sense for younger hyperopic presbyopes with low levels of ametropia and no noticeable lens opacities.
So the question remains: When should surgeons begin to offer refractive lens exchange? My short answer is when surgeons become bona fide refractive cataract surgeons, consistently hitting their IOL targets and seeing less than 1 D of astigmatism in over 90% of their postop cataract patients. This is where lens-based refractive surgeons share a real advantage. Never before have we had the opportunity to hone our skills for a refractive procedure like we now have with refractive lens surgery. We do not need to purchase expensive and rapidly antiquated equipment or hire specially trained technical support. We already have access to the tools we need to provide this service to our patients.
There are two important prerequisites for success with refractive lens procedures: a commitment to predictable results and the capability of keeping complications to a bare minimum. Thanks to the quiet evolution in modern cataract surgery, most surgeons can be successful, once they commit to a higher level of postop expectation. Let us look at a few important parameters that can help lens surgery become another choice for your unhappy hyperopic presbyopes.
Fixing a disability
The first step is to recognize just how disabling hyperopic presbyopia is for many of our patients. Sure, some do not mind wearing bifocals, and just like happy contact lens-wearing myopes, they probably are not good candidates for any refractive surgery. When screening cataract patients for multifocal IOLs, Dr. Howard Fine asks if they would see an advantage to reducing their need for glasses after their surgery. When an enthusiastic “yes” is the response, a discussion about the pros and cons of multifocal IOLs is likely to ensue. The same is true for pre-cataract procedures: finding motivated, understanding patients who are aware of the limitations and visual compromises of lens surgery with multifocal IOLs or blended vision but are so unhappy with their bifocal dependency that they are willing to proceed despite the costs and risks. These are the individuals who consider hyperopic presbyopia not to be a natural aging change but a functional disability, an impediment to the enjoyment of life.
|
|
|
(Images courtesy of Michael Woodcock, MD.) | |
Many surgeons remain on the sidelines when it comes to multifocal IOLs. This is not surprising. The same acceptance pattern was true after the introduction of the surgical microscope, rigid IOLs, phacoemulsification, foldable IOLs, sutureless surgery and topical anesthesia. The common denominator for all of these innovations to become commonplace has been, “What is best for the patient.” And for many hyperopic presbyopes, I believe multifocal IOLs are better than monovision after lens surgery or corneal surgery. Multifocal IOLs preserve physiologic stereoacuity and avoid eyes drifting into monofixation syndrome. However, many reluctant surgeons still feel that halos are too troublesome and contrast loss is too big a sacrifice. But for motivated presbyopes, these are non-issues. Their visual advantages of bilateral multifocal IOL implantation outweigh the disadvantages, especially after cortical adaptation. We explain to potential multifocal candidates that halos are expected because their brains have not yet learned how to tune out the near imagery (rings) overlying the distant image (light bulb). For almost all patients, these halos become much less noticeable after a few weeks, and their near vision begins to become easier to use.
Cortical adaptation
The Array is FDA approved for cataract patients 60 years of age and older. When implanting the Array in pre-cataract patients and those younger than 60, we inform them that this is an “off-label” use of an FDA-approved device.
Just as design changes have improved monofocal IOLs, future multifocal IOL designs will likely minimize halos and offer better near vision. Our early experience with the Alcon ReStor refractive-diffractive design has been positive and will soon offer us another multifocal IOL option.
I urge you to join your colleagues who have chosen to perform refractive lens surgery, especially for presbyopia. Begin to routinely measure binocular uncorrected distance and near vision after cataract surgery. If patients are regularly achieving at least 20/30 and J3 results, consider offering pre-cataract lens replacement for unhappy presbyopes. Like all refractive procedures, expect that your initial experience may not be all positive. But this is certainly where things are going. Our specialty is witnessing the next step in an amazing evolution in lens surgery. We have come a long way from creating +10 hyperopia with cataract surgery a generation ago.
Next month
Astigmatism reduction for refractive lens exchange.
For Your Information:
- R. Bruce Wallace III, MD, can be reached at 4110 Parliament Drive, Alexandria, LA 71303; 18-448-4488; fax: 318-448-9731; e-mail: rbw123@aol.com. Dr. Wallace is a consultant for Advanced Medical Optics.
- Advanced Medical Optics, maker of the Array lens, can be reached at 1700 E. St. Andrews Place, Santa Ana, CA 92799; 800-449-3060; fax: 866-872-5635; Web site: www.amo-inc.com.