During cataract surgery, your eyes natural lens is removed and replaced with an IOL. Standard monofocal IOLs probably will give you great distance vision Many times… patients require glasses after the procedure
Available IOL Technology: ◦ Toric IOLs ◦ Presbyopic IOLs Multifocal Accommodating These options are considered PREMIUM because they can provide a better visual outcome after cataract surgery than a standard IOL.
◦ Staar Toric IOL (Staar Surgical) Available in two powers Staar Toric IOL Silicone Material FDA Approval – 1998 Up to 3.5D.◦ Acrysof Toric IOL (Alcon) Corrects 1.5D to 3.0D astigmatism Acrylic Single Piece Lens Acrysof Toric IOL Increased Stability FDA Approval – 2005◦ Acrysof IQ Toric IOL (Alcon) Corrects 1.5D to 6.0D astigmatism Enhanced Aspheric optics Acrysof IQ Toric IOL UV blocker FDA Approval – 2009
Powers Range ◦ -1.50D to -6.00D Effective Power ◦ up to -4.11D Accurate Measurements ◦ Lenticular / Refractive / Corneal cylinder measurements Keratometry Topography Toric CalculatorThe AcrySof® Toric IOL Calculator is an easy-to-use, highly accurate tool that helps surgeons to select theappropriate IOL model and provides recommended axisplacement of the IOL in the capsular bag
Stability of the bag is in question ◦ An unstable capsular bag with pseudoexfoliation. ◦ In these patients, the lens may rotate once implanted, altering the patient’s vision.
Corneal topography shows anything other than the "bow-tie" pattern of regular astigmatism ◦ A toric IOL will probably not treat astigmatism successfully if the cornea is irregular
Since the mid 1980s, dozens of FDA trials have examined the efficacy and safety of presbyopia-correcting IOLs. Many early lenses demonstrated only moderate patient satisfaction. Today’s advanced and extensively tested technologies are yielding outstanding postoperative outcomes.
Multifocal IOLs Use technology called diffractive and refractive optics. This design provides both a distance and near focus at all times. Your brain will learn to automatically select the focus that is required at that time. Accommodating IOLs This design mimics the movement of the natural crystalline lens of the eye. Accommodating IOLs are able to move and/or change shape inside the eye to allow focus at multiple distances.
Second-generation, refractive multifocal lens. Aspheric transitions between zones provide intermediate vision +3.50D at IOL plane +2.85D at the spectacle plane Previously the ReZoom was considered the strongest multifocal IOL for enhancing intermediate vision, but now it has competition… FDA approval in March 2005
Uses an aspheric optic design to offset the spherical aberration of the cornea. +4.00 at the IOL plane According to FDA data, the Tecnis Multifocal IOL provides both good near and distance vision.1 Study found patients’ reading speeds to be 175 words per minute in bright light and 142 words per minute in low FDA approval in January 2009 light.
Most frequently implanted presbyopia-correcting IOL for cataract patients worldwide since 2005 Its design is based on the optical principle of apodization—a series of graduated steps that result in diffraction of light ReSTOR 4.0 ◦ +4.00 Add at the IOL plane ReSTOR 3.0 ◦ +3.00 Add at the IOL plane ◦ +2.50 Add at the spectacle plane The result is ability to focus on items at distance, intermediate, and near. FDA approval in March 2005
First and only FDA-approved accommodating IOL Designed to move within the eye, to provide focusing at all distances. Crystalens HD’s haptic acts as ―hinge‖ that allows the lens to move forward and flex secondary to vitreous pressure during accommodation. Aberration Free
Multifocal IOLs • These designs work because the brain learns to select the appropriate zone to "look" through to provide sight at near, intermediate or far ranges. • Diffractive multifocal IOLs, are great for distance and near vision, but are not optimal for intermediate distance and may cause minor amounts of distortion. • Major drawback is low contrast sensitivity. Accommodating IOLs • With one focusing zone it is less likely than multifocal IOLs to produce visual side effects for distance vision such as night vision problems including glare and halos. • At long distance, it is possible that vision may be crisper with accommodating IOLs. • May not provide as much of a range of focus (near to far) as multifocal IOLs, and this might lead to the need for reading glasses.
Getting involved in cataract procedure presents a great opportunity for the doctor/patient relationship Layout the options but make a recommendation Who knows more about the refractive status, eye A patient who reads a lot of health and complete eye paperback novels may be a better candidate for the care of the patient than ReSTOR, while a heavy computer the optometrist? user might be best served with a Crystalens.
Standard vs Premium IOL The final decision should be made between the patient and the optometrist, and then that decision should be communicated to the surgeon. ◦ Obviously this may be altered by the surgeons recommendations but having the patient already informed about their options is always welcome.
Good candidates are generally ◦ Easy-going ◦ Realistic in their expectations ◦ Willing to accept a few tradeoffs Patient must be aware of the cost of cataract surgery involving premium lenses. ◦ While most Medicare and private insurance will cover basic cataract surgery costs, you still will need to pay out-of-pocket the extra price of "premium" IOLs that are considered cosmetic and not medically necessary. These costs can be as high as $2,500 per eye. Several factors determine the IOL that best suits each patient. These include the patient’s occupation, hobbies, daily activities, pupil size and retinal health.
Clean Ocular Surface ◦ All of these common conditions must be addressed prior to multifocal IOL implantation to maximize patient outcomes. Dry eye Blepharitis Allergies Pathology ◦ Anterior segment Pterygium Corneal Abnormalities Chalazion ◦ Posterior segment Epiretinal membrane Macular Degeneration Glaucoma Etc. Understanding Astigmatism ◦ Keratometry ◦ Topography
Always mention glare and halos. ◦ Remind them of their current cataract symptoms of glare and halos, and that they may continue to see halos at night post- surgically, but to a much lesser extent. Nothing’s ever going to work as well as the natural accommodation system ◦ Remind them this is the best available technology at this time. They may occasionally need a pair of glasses from time to time. ◦ Especially when reading for long periods of time or in dim illumination
• The Optometrist should be able to recognize potential problems and be prepared for the possibility of other necessary surgeries. • These extra procedures should not be viewed as a complication of cataract surgery but as part of the process in obtaining good vision. • An Optometrist who is vigilant before and after surgery plays a major role in IOL surgery success! LRI (Limbal Relaxing Incision) ◦ This performed by making a pair of deep incisions at the corneal limbus, anterior to the vascular arcade. The length and placement of the incision is dependent upon the axis and amount of astigmatism. LRIs work well if the spherical equivalent is close to plano, and the astigmatism is under two diopters. LASIK or PRK ◦ Postoperatively, if the patient has residual myopia, hyperopia or astigmatism—may be a candidate for a touch-up LASIK or touch-up PRK. Piggyback IOLs ◦ This procedure can correct small or large spherical refractive errors after cataract surgery, but they are rarely utilized. IOL exchange ◦ Replacement of the IOL is always the last resort
◦ AcrySof IQ ReSTOR Multifocal Toric The company has said that it plans to file a pre-market application with the FDA in early 2012 for possible U.S. approval.◦ The At Lisa Toric Multifocal IOL. An aspheric, toric, diffractive bifocal IOL that corrects combined refractive errors.◦ Synchrony Dual-Optic Accommodating IOL. This is a dual-optic system. When the ciliary body is relaxed, the optics remain close together for distance vision. When the ciliary body contracts, the optics move apart, which increases lens power and provides optimum near acuity.◦ Tetraflex Accommodating IOL. Tetraflex (Lenstec, Inc) has two haptics and moves anteriorly secondary to vitreous pressure. This action, in turn, enhances near acuity.◦ The NuLens Accommodating IOL (NuLens Ltd.) Stated as having potentially up to 10 diopters of accommodation for a wider range of focus, compared to only about two diopters provided by currently approved IOLs.◦ FluidVision Accommodating IOL (PowerVision) uses fluid-based mechanics to change its shape in response to the movement of eye muscles. The lens is in the early stages of human clinical trials, but so far appears capable of providing more than 5 diopters of accommodation.◦ The Light Adjustable Lens. The Light Adjustable Lens is comprised of a photosensitive silicone material that can be postoperatively reshaped with ultraviolet light to correct any residual refractive error.
Historically, multifocal contact lenses have been perceived as complex and providing limited success. But the truth is, they are relatively easy to fit, enjoy higher—if not much higher— success rates compared to 10 to 20 years ago Multifocal lenses represent the best option for the majority of presbyopic patients who are interested in contact lens wear.
Diffractive designs ◦ Diffractive lenses utilize concentric phase plates to diffract light. ◦ This lens design induces significant ghosting of images.Due to these limitations, there are no current diffractive multifocalcontact lenses on the marketThe Hydron Echelon lens [CooperVision] was discontinued in March 2006
Aspheric designs offer a gradual change in power from the center to the periphery. ◦ Anterior surface ◦ Posterior surface Aspheric multifocal lenses in general provide a smooth progressive vision effect that simulates pre-presbyopic vision function.
Anterior Aspheric ◦ Plus power is greatest in the center of the lens progressing to more minus in the periphery. For very small pupils, the near power will be emphasized and distance vision will be compromised. For very large pupils the near vision will be compromised Posterior Aspheric ◦ Plus power increases toward the periphery. For very small pupils, the distance power will be emphasized and near vision will be compromised. For very large pupil the distance vision will be compromised
This design uses a distance or near optical zone, which makes pupil size and lens centration critical for the fit. ◦ Distance-centered ◦ Near-centered ◦ Pupil-intelligent ◦ Aspheric-blended varieties. This design incorporates distinct annular zones of power to create their multifocal effect.
Alternating or translating designs have the advantage of distinct and separate areas dedicated to vision for distance and for near. The positioning of the line of sight in alternating multifocals is entirely dependent on lens positioning in primary gaze and translation upon inferior gaze. The distance and near portions of the lens are never used simultaneously. Lens stability controlled by either prism or truncation.
With appropriate base curve selection andproper lid interaction, the lens will translateup during downward gaze allowing thepatient to utilize the add in the lensDuring primary gaze, the segment ispositioned below the pupil allowing thepatient to utilize only the distance portionof the lens
Most GP multifocal lenses utilize alternating vision effects to some degree because they move with the blink and will translate to varying degrees with inferior gaze. With isolated exceptions, soft and hybrid multifocal lens designs are simultaneous designs because they do not move significantly with the blink or translate with inferior gaze.
Advantages ◦ Offers intermediate vision ◦ Near can be viewed without using downward gaze ◦ Lens design is thinner and more comfortable to wear ◦ Stereopsis is maintained ◦ Lid positioning is not as important to the success Disadvantages ◦ Pupil size is a consideration to success ◦ Patients may experience flare and ghosting ◦ May experience reduced night vision
Advantages ◦ Gives sharp distance and near vision ◦ Not as dependent on pupil size ◦ Interferes less with night vision Cons ◦ Less comfortable due to edge thickness ◦ No intermediate vision ◦ Lid tension and position must be appropriate for design to work ◦ Can only view near on downward gaze
The soft multifocal contact lens market is dominated by the silicone hydrogel designs from the major manufacturers.
Back of your mind Baseball Player ◦ Distance Lawyer #1 Mechanic ◦ Intermediate Drive at night ◦ Near Waiter in restaurant Security Guard #2 ◦ High Light (small pupil) Photographer ◦ Low Light (large pupil)Anterior Aspheric Posterior Aspheric Distance Center Concentric Near Center Concentric Alternating
The key to fitting success is to appropriately match an individual patients vision demands and with the proper design. Success is based on the realization that no one lens design is superior to another.
Motivation Expectations Cost and patient compliance Physical considerations
If a patient is not motivated psychologically… it is going to make your job that much harder. Appearance - Patients wear contact lenses because they want to lose the glasses. ◦ Multifocal lenses psychologically hide this aging process. Convenience -Presbyopia is especially frustrating when its new. These patients never had a problem to read a menu, sign a check, etc.
What are the patients vision expectations? How and when do they want to wear multifocal lenses? Does the patient want to wear contact lenses full time, daily yet limited hours, or occasionally? What specific activities are most important? Consider the vision demands of those responses and how the various designs might perform under those circumstances.
Discuss ◦ Comfort ◦ Cost ◦ Acceptance If you are able to discover that a given patient is not able to afford multifocal lenses, or that he would not accept the vision outcomes available, or would not be able to tolerate physical lens adaptation, then you could avoid wasting his time and yours.
There are certain anatomical factors that will help you choose an appropriate lens design ◦ Corneal Abnormalities ◦ Tear film quality and quantity. ◦ Lid margins Anterior and/or posterior blepharitis. ◦ Allergic conditions Also be aware of all prescribed that can affect the corneal surface. Pupil size is important, especially in extremes.