Acuvue Bifocal Roundtable

Contact Lens Spectrum editor, Joe Barr, moderates a discussion between four practitioners about the possibility of bifocal contact lenses replacing monovision.

MARCH 1999

Dr. Barr: Where are we with successful monovision and bifocal contact lenses today?

Dr. Kame: As creatures of habit, I think I would instinctively use monovision with a first-time presbyope because usually I'm only using an add of up to 1.00D. I'm not apt to put even a +1.00D bifocal on a patient that needs 0.50D or 0.25D of add. When that patient starts getting up into the area of let's say, 1.25D add, then I'm apt to consider the bifocal.

Dr. Shovlin: I like the option of having the Acuvue Bifocal in a low add power even if you're forced to use it in one eye in those requiring some minimal add power. In most cases, you'll find a binocular acceptance to excellent distance acuity in a +1.00 add correction.

Dr. Caffrey: I think I'm going to try to change that habit. If we look at it again more like spectacles, we don't take their spectacle prescription and cut back a half when they're new presbyopes. We give them a 0.75D add or even a 1.00D add even if it is a little more than they need. I have the sense that getting them started with binocular presbyopic correction, meaning bifocal contact lenses, might allow them to continue to adapt. I'm sort of hoping that the profession starts to fit bifocals in the earlier stages of presbyopia and then bump up the add from there if they're successful. If they're not, your second option is monovision.

Dr. Quinn: I think the key with an incipient presbyope is to assess their symptoms. If their presbyopia is affecting their ability to perform day-to-day functions, then they are good candidates for the Acuvue Bifocal. The greater the symptoms, the greater the likelihood they will appreciate the bifocal and adapt to it quickly.

Dr. Kame: I think what happened is that we now accept monovision as the safe and legal mode of care, while ten years ago, everybody was reluctant to pick monovision.

Dr. Caffrey: My least successful conversions are people who are happy in monovision. But the emerging presbyope should have the benefit of binocularity and good distance vision if we can give it to them.

Dr. Quinn: I find that the key with monovision patients is to determine whether they are happy or just tolerating monovision. If they have complaints relating to night driving or problems with depth perception, I'll apply a bifocal lens to the near eye only. This allows them to have distance vision in each eye. If a monovision patient has no symptoms, I keep them in monovision.

Dr. Barr: So, there's a paradigm out here. The paradigm is for most practitioners to prescribe monovision for the emerging presbyope, whether they're a lens wearer or not. What Barbara is suggesting is that the paradigm shift is to go right to bifocals. So taking into account all the possibilities, not just Acuvue Bifocals, what will get eyecare practitioners to adopt that approach to try bifocals first?

Dr. Shovlin: Marketing studies have shown that over 30 percent of our presbyopes want bifocal contact lenses. Sadly, less than one percent actually wear them. The biggest impediment is the practitioner's mind set. In most cases, this lens option is an easy-to-adjust modality since there are convenient trials and an easy-to-fit concept. Some effort may be required to attain the success that Vistakon predicts. You must be willing to change lens powers and adjust away from a balanced add effect in some cases.

Dr. Quinn: I can tell you that I made the shift without really being aware of it. I've had the opportunity to work with the Acuvue Bifocal for over two and a half years now. I truly believe that patients successful with it are operating at a higher visual performance level than a successful monovision patient. Intuitively, patients understand the benefits of distance and near vision in each eye. Monovision strikes some as a lot of smoke and mirrors.

Dr. Caffrey: I think the Acuvue Bifocal offers you that freedom. So we can take a much broader group of people to put the contact lens on, and give them lenses for a week to use in their environment. Therefore, this lens becomes the lens of choice. I would say it's simple, it's comfortable, and you can figure out right that day or week whether or not it's a workable lens.

Dr. Kame: We just have to kind-of revisit good binocular vision. If they don't get good binocular vision, then we have monovision as a back-up. I'm thinking of putting the bifocals on first. Even if I think I'm overcorrecting them. I may be overlooking a real opportunity.

Dr. Barr: I think it's good for everybody if we say who the good and not-so-good candidates are for the Acuvue Bifocal lens.

Dr. Shovlin: Low cylinder refractions are important. Generally, cylinder more than one-fourth the sphere or less and in some low against-the-rule cylinder. Patients who are extremely good candidates are those who have already experienced the benefits of two-week replacement, are interested in the merits of UV protection, desire a visibility tint and either reject the notion of monovision or have failed in the past with monovision. This lens also has approval for overnight wear, so I think it's a good choice for those who need to wear lenses for long periods but not necessarily overnight.

On the other hand, poor candidates are those who have unrealistic expectations and who have general contraindications to soft lens wear due to significant anterior segment concerns in maintaining a safe lens environment.

Dr. Caffrey: One important factor is refractive error based on lens availability. The other important thing is the astigmatism factor. My cutoff is 0.75D of astigmatism. There is only one size and a base curve, so a very steep or very flat cornea may not be acceptable, but until you put the lens on the eye, it's difficult to know that. After that, I think it's like anything else when it comes to visual tasks. What is it that the person does all day? Their needs in terms of both work and play are very important.

Dr. Quinn: I'd like to comment that it is very important to start with a current, accurate baseline refraction. The refraction is the foundation upon which the contact lens prescription rests. A difference of 0.25D can have a very significant impact on the outcome. Much more so than with single vision contact lenses.

Dr. Kame: Based on the recent experience we've had, I would try it on any patient. I'm really not sure of the limits because there are always exceptions to every rule. Yes, I usually don't want to go beyond 0.50D or 0.75D of cylinder, but I may even challenge a 1.00D or 1.25D patient if it's only one eye. So I proceed with real caution with myopes, but I would try it on almost any myope.

It's also very important to set expectations for the patient. Regardless of what I look for in a patient, I want them to know what to expect. I don't want them to expect to have their eyes as when they were 20 years old. I tell them that they'll have ranges of vision and that we are going to work together to put that range in the appropriate area. So if they are computer workers, we emphasize that the computer is important. Now they have to tell me if the near point is more important than the far point. By doing that, I try to set up for success rather than failure. I tell them also they may have to use a weak pair of supplementary eyeglasses like 0.50D driving eyeglasses or even 0.50D of a reading lens just to be able to expand that range. I find that when I do this, patients are willing to bend a little. So if I were to start with any patient and present them with limitations, I've usually already covered myself, so basically I think it is very important to set expectations.

Dr. Barr: Let me ask you to get more specific about low myopes versus high myopes, low add verses higher add, against-the-rule versus with-the-rule. As you deal with these, how does the disposability come into play? Do you just find it good that you can try different adds and different distance powers or do you even give a trusted patient a few different lenses to see which one works the best in terms of range, vision and distance power?

Dr. Quinn: I tell patients two things. First, all forms of correction require adaptation and adjustment. I review compromises they've had to learn to live with wearing bifocal spectacles and they all nod knowingly. Second, my goal is to meet most of their visual needs most of the time. I bring it right out front that they may find spectacles serving them better than contact lenses for certain activities, such as long night drives. Discussing this at the outset makes it a non-issue.

Dr. Shovlin: I also like this lens on those patients who have little or no distance refractive error. In most cases, it's far superior to monovision even when you need to place it on only one eye. Supplemental spectacles are still a possibility and some patients are receptive to this. Dissimilar adds are not a problem and is needed in some patients to attain acceptable distance near acuity.

Dr. Caffrey: I used to do that a lot with monovision. I used to send them home with several different non-dominant eye powers to see how they would do and which they preferred. They found out what worked in their workplace.

That's a very creative idea. I hadn't thought about doing that with bifocals. Now that I think about it, we could even do a modified monovision for those who are concerned about distance vision. Fit one eye with the single-vision Acuvue and the other with the bifocal. There are a million combinations. I think it's very nice for patients to figure those things out for themselves at home. I'll tell you my criteria for low myopes if I may. Patients who come in and say that they've stopped wearing lenses to work now because they really like reading with just their bare eyes are lousy candidates. If a patient is -2.00D and likes to sit at their desk and doesn't mind the blur when they're doing near work, they are very unlikely to be successful with the bifocals because you cannot recreate that. But those who are low myopes and say they're not wearing spectacles are obviously an excellent candidate.

Dr. Quinn: I don't think I can emphasize enough how the disposable aspect of the Acuvue Bifocal has helped me integrate it as a major player in my office. The lens can be presented, trialed and tweaked all at the patient's initial visit. All at little financial risk to the patient or the doctor.

Dr. Kame: Patients who work at computers do very well. I love being able to put these on and see that it's not really a bifocal. It's a multifocal. There are overlaps in the power. I find that it's most gratifying for those patients.

Dr. Caffrey: The concept of three prescriptions is a very important one in presbyopia. We now have distance vision, mid-range and reading vision. I explain this to patients in a three-prescription format and I always stay with the most accurate two. We may not be able to look after all three, but it's usually understandable and worth it to them.

Dr. Quinn: I agree, the contact lens works great for the computer user. Another group I've had good success with is teachers. They need good intermediate vision to look over kids' shoulders at schoolwork on their desk, near vision to refer to notes and texts, and distance vision to make sure Tommy in the back row is behaving. I also have a physician who sees a lot of kids. She says that the Acuvue Bifocal is great for looking at eardrums. She doesn't have to cock her head back like her colleagues who wear bifocal spectacles.

Dr. Kame: Disposability is largely what makes it work. My bifocal patients have reusable lenses. The lenses get clouded, they start to change and they may work with them, they may work against them -- and it's kind of like starting all over. With the Acuvue Bifocal, we're changing them so often and we have the consistency and predictability for the patient. I think it's user-friendly both for patient and doctor for this one reason.

Dr. Barr: One of the things that I find to be most difficult with former presbyopic contact lens wearers is the shock of lens replacement cost. Even if they know how much it's going to cost to replace a contact lens, once they actually see how much that replacement lens is, it tends to be very substantial in many custom lens design cases, but it can scare a lot of people away.

Dr. Caffrey: They hang on to them too long, the contact lenses are dirty, their vision is going and they have a reaction to it. I think a tough patient is the presbyope who has never had a prescription and doesn't need one, or the plano patient who is now plano with a plus one add.

Dr. Quinn: Emmetropes are a tough group. But often they are very motivated as well. They've had 40 years of visual freedom and are not excited about having spectacles sitting on the end of their noses. I've had some success fitting a bifocal on the non-dominant eye only and leaving the dominant eye alone. Consequently, I spend a fair amount of time preparing the patient for what to expect with distance vision.

Dr. Barr: Let's talk about the most important Acuvue Bifocal fitting tips that you can come up with.

Dr. Shovlin: It's extremely important to allow time for equilibration (15 minutes). Avoid the temptation of using the phoropter. I really enjoy using the flippers provided by Vistakon. Remember that the add labeled is a true add effect power. I often find myself reaching for a lower add than a higher add power in lens selection because of the adds' effect on distance vision. It's tempting to refract too tightly on the first visit. Give the patient a chance to experience the benefits of this product. It's not uncommon to change one or both lenses on follow-up. Always remember that a �0.25D change can have a profound effect on the visual outcome and ultimate success of this lens in your practice. Any time you increase the add power, there might be a worsening effect on the distance prescription of the non-dominant eye rather than change the add power. I haven't seen any data on outcomes of hyperopic versus myopic distance corrections and success rates. I would guess from just our short exposure that it's probably close in percentages of success for each group.

Dr. Caffrey: The most important thing is to wear the right side right. If you don't, you can't see.

Dr. Kame: It's so easy to fit that it almost scares me sometimes to think. I will usually just take the sphere and add and go from there.

Dr. Quinn: The physical fit of the lens is generally not an issue. The challenge is to prescribe the correct power -- the power that will balance vision at all distances required to meet the patient's needs. The most common mistake I believe doctors will make when just beginning to fit the Acuvue Bifocal will be to give the patient too much minus power in the distance correction. If you are someone who habitually pushes plus during your refraction, you may find you need to add -0.25D or, in some cases -0.50D. If you're adding more minus than that, you're in trouble. Near acuity will suffer.

Dr. Shovlin: The labeled add power is a pretty true add effect for most patients with a well-centered lens. One caveat, as is the case with most simultaneous lens designs, is that it's easy to over-minus patients at distance, which in turn will hurt the near response with this lens. Remember to push as much plus at distance especially with the nondominant eye.

Dr. Caffrey: I've never had a patient say that one of those lenses in that box didn't give them as good of vision as the previous contact lens. I think that's important.

Dr. Shovlin: The quality of this lens from labeled power to optics is exceptional. It's nice not to have to worry about the issue of poor quality control, especially when it comes to replacement lenses. There's nothing more frustrating than achieving initial success, only to be frustrated by replacing a lens that doesn't work as well as the original lens did before replacement.

Dr. Kame: I tend to use the minimal plus, knowing that I can just go back and change it right away. I always start on the most plus side distance and the least plus side near. I want to have that range as wide as possible. Then I'll add on the plus for near or the minus for distances. If I change the distance by 0.25D, I'll increase the near plus by 0.50D. I will not go a whole diopter. If I change the distance, increase the minus, I don't want to push the plus up close. I think it just shortens it up too much. When getting into the +2.50 add, I do it with a good deal of caution. I find that I might start compromising distance. Then I have to adopt a modified monovision and modified bifocal as much as possible. But, you know, you have certain cases where it's legitimate. They are very cooperative patients.

Dr. Quinn: If the patient has a little cylinder, I'll take that out of the phoropter and see if they would like a little more minus in the sphere to center the interval. Again, I do everything I can to make sure that I don't give them too much minus in the distance. For the add, I go with the spectacle add. If it falls between available adds, I go to the next higher add.

Dr. Caffrey: Generally, I use the spectacle add as my starting point. I don't push plus in the distance, but I do give them whatever adds I have given them as a spectacle add. I figure out both by having them sit at my desk with the computer and read a book, simulating their life as much as I can.

Dr. Quinn: If the patient's in a high add and has complaints of distance blur, I'm more likely to cut the add to +1.00 or +1.50 in the dominant eye rather than increase minus in the distance power.

Dr. Barr: In your office, what does the patient do while they have that first pair of trial lenses on?

Dr. Kame: I don't emphasize the Snellen chart. I ask patients to look at visual things that they might be accustomed to, like certificates on the wall or magazines from the magazine rack. I'll have them step up and walk around to different areas of the office and have them go to the counter to see what it might be to shop by looking at solution bottles. I want to be sure they have good vision and that they are usually very happy about the fact that they can look at something and see it at a good range. I ask them to take it this way and also to look at a clock off in the distance.

Dr. Quinn: After I apply lenses, I ask the patient to leave the examining room to experience a more natural visual environment. I, or someone on my staff escorts the patient to the reception area and encourages them to visually explore. Not only does this give the lenses time to settle, but it provides me with valuable information. When the patient returns to the exam room 10 to 20 minutes later, I ask them a very open question, such as "How are you doing with the lenses?" If they have complaints with vision at a given distance, I know where to focus my energy. If they have no complaints, it's likely I won't change anything, regardless of acuity findings.

Dr. Shovlin: Waiting 15 minutes is crucial. It gives the patient some time to respond to their short experience with this product and share that with you in the exam room. I still think you need to avoid the temptation to change lenses too soon.

Dr. Kame: "Twenty happy." I think that's a good way to remember it. You want to give them happy, functional vision.

Dr. Caffrey: I like to see a binocular 20/20 in a distance and what I have found traditionally is that the near vision is good. If there is anything that patients might say, and it's not acuity, it's something about perception at certain distances. I'll walk to the end of the room and ask when they were able to recognize my face and things like that.

Dr. Barr: One of the ways I think you can tell if someone really uses bifocal contact lenses as a practitioner is that they know that there are some patients that will have 20/20 at distance and 20/20 near and be unhappy. Most people don't need 20/20 at near. You can have 20/30 at distance binocular and 20/50 at near and they can be thrilled.

Dr. Quinn: I believe that it is critical to assess vision under binocular conditions. That's the way the visual system works in the real world. It's a more realistic reflection of real world performance. The only time I assess vision monocularly is when troubleshooting.

Dr. Caffrey: And all of that may be personal. I also think that there is something measurable there, with this facial recognition thing, whether or not that's contrast sensitivity. We don't have the tools yet to understand it or measure it, but I'm sure there's a physiological reality to that 20/20 unhappy person.

Dr. Barr: I think that some of the cases people call failures are the "not good acuity but happy patients," so they tell them they can't wear those lenses. However, people can be very happy even though, for example, their low contrast acuity may not be very good. I think one of the keys here that we've hit on today is a kind of simplification. Are there any other comments on how we can simplify the process? This company has gone to a great deal of trouble to define a very specific, careful, I'd almost say elaborate, fitting process. Yet, not everybody is always going to follow protocol. It's probably one of the worst fields in the world for people following protocol on fitting. Are there any other tips you'd recommend on prescribing?

Dr. Shovlin: Don't second guess the consultants. The same practitioners that made some mistakes with this lens and now have the experience that we seek when we start using the Acuvue Bifocal have offered valuable suggestions on how to increase success. It's indeed humbling to have to read a fitting guide, especially since we think we've heard it all before. There are some excellent suggestions and tips to help provide for a greater yield in successful cases. Your success rate will increase dramatically if you read the guide first. I know of some very competent practitioners who almost gave up on this lens because they didn't take the time to read the fitting guide.

Dr. Quinn: You must work without the phoropter to be successful with this lens. It took some getting use to, but now I'm hooked. I've become a flipper fanatic! They're easy and they're efficient. Small changes can be demonstrated and their impact assessed in an instant. Most importantly, they help me avoid overminusing.

Dr. Kame: By using the retinoscope, it clearly defines if this patient is having a problem with the contact lens per se, or just a tearing problem. It's very obvious when you see it. The first thing I do is put in a drop of saline. If this doesn't help, I clean the lens and then put it back on. Almost immediately, they are able to see better, and you restore what you expect them to see. In the worst case, I might even change the lens.

Dr. Barr: What about lens handling? Some presbyopes, especially the hyperopes, aren't swift sometimes and they're not previous contact lens wearers before the handling instructions. Are there any tips on handling to help people with that, or should I maybe ask your staff that question?

Dr. Shovlin: Allowing the lens to dry will indeed help. However, some will never see the inversion aid (the 1-2-3 mark).

Dr. Quinn: The lens is thin and can be challenging to manipulate in low powers. The good news is, its thinness allows for extended wear capabilities.

Dr. Kame: Is it true that if you let the lens dry, the 1-2-3 mark becomes more visible? I don't see very many problems remaining. Our main problem was not knowing if the lens was inside out.

Dr. Barr: Let's just finish with this: is there a particular opportunity to current Acuvue wearers for this lens?

Dr. Shovlin: It's an easy sell with two-week disposability, but don't limit it to just that experienced group. Conventional lens wearers certainly like the transition from SureVue and Acuvue.

Dr. Kame: They have been my best candidates.

Dr. Caffrey: They believe in the name of Acuvue, and it's the natural evolution for them to switch from their Acuvue single visions to the Acuvue Bifocal contact lens.

Dr. Kame: There's one down side to it that we've encountered, and that is a patient who is wearing Acuvue successfully will say, "Well, these are Acuvues. Why should I have to pay a refitting fee?"

Dr. Barr: What do you do?

Dr. Kame: I call it an upgrade fee or whatever it might be. We don't have a large upgrade fee. We charge $50.

Dr. Barr: A refitting fee, if you will, and then the additional cost of the packages?

Dr. Kame: And the price has not been an issue for those patients. It's just the term "refitting fee." In other words, if it's called something else, it might not be an issue.

Dr. Quinn: I tell patients the Acuvue name tells you the lens is manufactured by the same company, but the Acuvue Bifocal is quite a different animal, requiring us to pretty much start from scratch. Since the patient already has been trained in lens handling, their cost is reduced a bit because we don't have to go over it.

Dr. Barr: If I'm that patient and I'm in that chair, what do you say to me and what does your staff say to me?

Dr. Shovlin: Most patients realize that there is a definite upgrade, especially since they can effectively see at near as well as at distance with each eye.

Dr. Kame: We base it on service and time. We say, "You're going to have to come back an extra visit or two or whatever," and they kind of begin to accept it. Initially, to them they think they're getting the same thing. The Acuvue lens carries such, it has a good name, but they can't seem to make the transition to the fact that the Acuvue is not a bifocal contact lens. There is a vast difference so we have to take the time. There again we're talking about chair time and what are they expecting. That's been the only resistance we've had.

Dr. Caffrey: Maybe I can add one other reason, and that is fitting a contact lens relates to the size and curvature, and the bifocal is a different size and curvature and therefore, you're actually doing a fitting process to make sure that physiologically they're going to be fine.

Dr. Barr: Any other global or not-so-global comments you'd like to make about the lens, presbyopia and contact lenses in general?

Dr. Quinn: I've been pleasantly surprised to find that approximately 30 percent of the patients I have in the Acuvue Bifocal have never worn contact lenses before. I guess single vision spectacles are okay, even a fashion statement, but when it comes to bifocals, that's another story.

Dr. Kame: I'm not sure if I'd use them on part-time wearers successfully. I'm not sure what your experience is.

Dr. Quinn: I've had a few patients enter with part-time wear in mind, but seem to end up wearing them more.

Dr. Caffrey: Part-time wear means one day to me. Part-time doesn't mean bifocals to me. That's my mind set.

Dr. Barr: Does room lighting make a difference in your clinical results?

Dr. Shovlin: Johnson & Johnson has done extensive research on mechanics of zone size for pupils in contact lens wearers under various illuminations. The lens is described as a "pupil intelligent" design.

Dr. Kame: I have not tested it out because I am of the belief that I want my room illumination to be fairly close to what is considered normal. I don't darken my exam room real dark anyway. I always make it a point to go out into the reception area, and to me, I guess I'm testing under different types of illumination. Certainly, in the exam room I don't turn the light up to see if it makes any difference.

Dr. Caffrey: I think this brings up a good point. In presbyopia, we are all getting less light to our retinas all the time, and it might be the cue to tell them to reorganize their work space so that their particular lighting conditions are appropriate. I think that in itself might help, and also they're going into this bifocal, so it's another way of seeing and they have to optimize everything.

Dr. Barr: Can you have so much light that you lose the add effect?

Dr. Shovlin: I definitely think that optics suffer with exceedingly small pupils, especially as we age and have to be concerned with a less-than-perfect ocular media.

Dr. Quinn: I know Vistakon spent a lot of time studying pupil size relative to changes in illumination. Good light helps near vision. I've not heard any comments regarding too much light being detrimental to near vision.

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This Roundtable discussion was sponsored by Vistakon

All members of the roundtable are diplomates in the Cornea and Contact Lens Section of the American Academy of Optometry.

Dr. Rodger Kame is in private practice in Los Angeles, Calif.

Dr. Barbara Caffrey has practiced optometry in Toronto, Canada, in a group setting, dedicated to contact lens and tear film research since 1977.

Dr. Thomas Quinn is in group practice in Athens, Ohio, and has served as faculty member at the Ohio State University of Optometry

.

Dr. Joseph Shovlin is director of the Contact Lens Service at the Northeastern Eye Institute,
Scranton, Penn.