Article

THE WORDS WE CHOOSE TO DISCUSS MULTIFOCALS

Explaining changes to the visual system and setting realistic expectations can empower patients to succeed in multifocal lenses.

We are all looking for ways in which we can do better for our patients (and for our practices) while hopefully doing less work ourselves. The contact lens industry has provided us with great products that work better than ever before. We also have the knowledge and awareness to evaluate and manage ocular surface disease, which dramatically helps with comfort issues that our contact lens-wearing patients face. Our next step is to understand and realize the importance of patient communication and how that factors into what we do.

Fitting contact lenses successfully is complex. Fitting multifocal contact lenses is even more so. However, with many practitioners fitting multifocals on a daily basis with great success, we have to ask: How are they doing it? In this article, I hope to share with you ideas on how to improve patient comprehension of presbyopia, the process of change through which your patients are going, and how multifocal lenses work and what to expect from them. The hope is to ease the fitting process, improve the wearing experience, and prevent patients from dropping out of contact lens wear entirely. As always, the primary goal is to reduce patient frustration, increase patient satisfaction, and elevate your practice’s multifocal contact lens success rate.

Defining success is a variable in itself. A patient’s perception of success versus a practitioner’s perception of success can be different. If both parties are on the same page and speaking the same language, the all-too-common communication disconnect can be eliminated, and overall success can be improved.

A recent study showed that of all neophyte multifocal contact lens wearers, 57% remained in them (Sulley et al, 2017). Almost half of those who did drop out did so in the first two months of wear. Vision complaints were the primary concern—not comfort, which has traditionally been considered the primary issue when talking about contact lens dropout. Interestingly, of those who did drop out, 71% of them were not given an alternative lens or management strategy (Sulley et al, 2017). Therefore, we can see that providing options is important, as is making sure that our patients come back to us with their complaints so we can help them, which will hopefully increase the retention rate.

LET’S TAKE A STEP BACK AND REGROUP

At the heart of the matter is presbyopia. More patients than ever are dealing with loss of accommodation; approximately one-third of current patients are presbyopic, with 2.3 billion presbyopes worldwide expected to surface by the year 2020—135 million of whom will be in the United States (Sulley et al, 2017; www.siliconehydrogels.org/editorials/previous_editorial_jackie_tan.asp ).

If you ask patients, students, or eyecare practitioners what presbyopia means, a definition involving the loss of accommodation or focusing ability due to age usually follows. But is age the only factor we should be blaming these days?

Standard practice is to refract patients at a distance equal to 20 feet away. Our patients then take our fantastic, crisp, long-distance prescriptions and work with tools such as computer monitors, laptops, tablets, e-readers, magazines, books, and cell phones, all of which are less than three feet in front of them. A 2015 report by the Vision Council on digital eyestrain noted that more than 90% of American adults use digital devices for at least two hours per day, with close to 30% of individuals using digital devices for more than nine hours each day (The Vision Council, 2016; The Vision Council, 2015). Our visual world is much closer to us today than it was in the past. As a result, our patients are accommodating for longer hours than they have in the past.

Anecdotally, I am seeing patients entering into presbyopia and requiring near assistance at a much younger age compared to a decade ago. Younger patients are relying on their accommodative and convergence systems more than they ever have and, as a result, are losing the ability to focus at near at a faster rate compared to those who did not have the same visual demands in the past.

Our industry, as a whole, is catering to these pre-presbyopic patients more so than before. Preventive strategies to reduce accommodative stress and fatigue are a huge focus these days. Exercises, visual breaks using the 20-20-20 rule, and ophthalmic tools—baby progressives, as I call them—have been introduced within the last year to help mitigate accommodate stress.

With all of this in mind, it is possible to conclude that in addition to age, we should consider digital devices, technology, and our new visual world to be a primary source of early-onset presbyopia.

A SYSTEM OF 10—NEW EXPLANATIONS OF PRESBYOPIA

When I speak to patients about presbyopia, blaming age is not an option for me. I have changed my approach so that I can help patients better understand what is occurring to them without making them feel bad. With presbyopic changes sometimes occurring at a relatively young age, it seems odd to mention age as a factor to a 30-year-old patient.

Generally, presbyopia occurs between the ages of 30 and 65 years with the loss of the ability to accommodate a minimum of 2.50D. We can compare this to a loss of 10 units of accommodative strength if broken into 0.25D steps. I describe to my patients that the focusing system has 10 units of energy, and over a 35-year period, we will all lose those 10 units. The rate at which we lose them is very individual, however, and greatly depends on the amount of near work that we perform.

For example, if patients present to the clinic with a +1.50D add, they have more than likely lost six units of their accommodative muscle energy and are functioning with only +1.00 accommodative ability or 40% of their initial ability. These patients would require six units (6 x 0.25D = +1.50D) of add/magnification support to return to their full potential. These six units are added to their distance prescription to provide them with their best reading vision. When their accommodative system is running at 100%, the rate of change could potentially slow down.

Using this unit system of 10 has been very beneficial when explaining the process, pinpointing where patients are in the process, and demonstrating how many more steps of change lie ahead. Being comfortable is the key. Pushing the focusing system to work harder than it is able to does not help in this situation. This explanation helps patients understand how much of the accommodative system they have lost, enabling them to track their own personal rate of change.

Blaming technology for why everything is changing so quickly has helped ease my patients’ distress regarding the changes that they are experiencing. This has also reduced concerns about frequent lens prescription changes that will be required, and it tackles the misconception that reading glasses caused more deterioration once they started wearing them.

The system of 10 units can also be used to clarify how a pair of progressive lenses is a linear system, while a soft multifocal lens is typically designed in a circular pattern (Figure 1). Explaining the differences in glasses and contact lens designs is key to clarifying how these products work and understanding why starting earlier prevents the frustration that so many feel with progressive glasses.

Figure 1. Progressive lenses (A) usually have a linear design, while multifocal contact lenses (B) use a circular design.

With the earlier onset of presbyopic needs, we have overcome this resistance to progressive glasses and multifocal contact lenses by highlighting computer focusing trends, explaining the system of 10 units of change, and initiating the conversation sooner with each patient.

Most importantly, beginning patient education early is key to achieving greater fitting success using either progressive ophthalmic lenses or soft multifocal contact lenses. Patients who have a lower add amount typically have an easier time adapting to both progressives and soft multifocal lenses compared to those more mature presbyopic patients who have much higher adds.

THE COMPLEXITY OF THE VISUAL SYSTEM

Broadly speaking, there are two multifocal lens designs: translating and simultaneous vision. For the most part, translating designs (Figure 2), which resemble traditional bifocal and trifocal ophthalmic lenses, are only associated with GP contact lenses. These provide crisp vision and are suitable for higher add demands. To achieve reading assistance with these lenses, patients must drop their eyes and view in downgaze. The advantage of soft multifocal contact lenses, when the prescription allows, is that reading can be performed in any direction of gaze.

Figure 2. Explaining how each lens works will help patients understand the difference and will help ensure successful contact lens wear.
Image reproduced with permission from AllAboutVision.com

Simultaneous vision is the process through which multiple prescription powers are presented to the visual system at the same time, all within the center of the lens. The patient’s visual system then chooses which prescription to focus through to see the image in question at the selected distance, while ignoring the other prescriptions. Simultaneous vision designs are available in both soft and GP lenses in either concentric or aspheric designs (Figure 2). By definition, concentric designs alternate between distance and near rings in a repeating manner. Aspheric designs progressively change from distance to near. Currently, there are only aspheric soft lens designs on the market in terms of mass-produced frequent replacement lenses. However, there are some custom lenses available in concentric designs.

Explaining to patients the complexity of the visual system and how simultaneous vision lenses work can help them better understand the design and the fitting process, which truly is more of an art than an exact science. It is important for your patients to understand that two patients who have the same prescription and the same daily tasks may interpret these lens designs differently because their brains work differently.

Changing the power of these lenses changes the distribution of the design, which helps a patient to interpret the designs better. Ensuring thorough patient education also helps to alleviate any blame that the patient may place on you or the lens design for perceived inadequacies when their ability to adapt to simultaneous vision may be the issue.

INTRODUCING SOFT MULTIFOCAL LENSES TO PATIENTS

There are several steps to consider when introducing patients to soft multifocal contact lenses. Passive marketing—via paper or electronic signage in your reception area or dispensary, or questions on your intake form—can introduce the concept to patients. For a more active approach, staff members can inquire about interest in multifocal lenses during the registration process, pre-testing session, or at checkout following the appointment. However, the most important discussion, in my opinion, comes directly from the practitioner. It can be as simple as asking for a patient’s interest in contact lenses and providing an update on new products available, or it can be a more targeted presentation of available options.

When patients express interest in multifocal contact lenses, take a few moments to really review what the fitting process entails. Explain presbyopia and its current effect and future impact on their vision. Relay the available advancements in technology and multifocal options, and continue by describing the pros and cons of the lenses and their designs. The fitting process, follow-up timeline, issues or complications that they may experience during adaptation to the lens, and, lastly, the cost should all be reviewed before putting a single lens on your patients’ eyes. Providing patients with an understanding of the entire process helps them understand what the fitting is all about and the reason for a fitting fee, which will make your job much easier in the end.

Fitting Time At my practice, we find that it can take about 2.5 visits on average to fit a soft multifocal lens properly; the exact time frame will depend on the amount of add power needed and each patient’s adaptability. To avoid patient frustration, always make them aware of this fact ahead of time so that they can plan accordingly. Don’t try to squeeze in a multifocal fit during your regular examination time slot with a patient; it will likely result in delays with subsequent patients, creating stress and dislike for fitting these lenses.

During the initial visit, a patient should expect to devote 20 to 30 minutes to lens adaptation. During this time, ask patients to test their lenses using various viewing materials in the office.

A small change in power can alter the distribution of the pattern on the lens surface, changing how their eyes react to the design. Thus, it is important to give them time to adapt in the office prior to making any adjustments to the power of the lens. Patient adaptation to these lenses may continue for several days after the initial fitting. Real-life visual demands beyond the office setting may alter a patient’s judgment on quality of vision as well. I inform patients of this and require a one-week follow-up visit to reassess the fit and the visual performance of the lens. It is so important to remind patients to come back and to not become frustrated. The purpose of the follow-up visit is to manage any issues that they may have experienced during their week at home.

Fitting Limitations When discussing limitations with patients, mention the design of simultaneous vision lenses and the importance of adequate light. The human pupil is a dynamic system, while soft multifocal lenses are not; a simple explanation regarding how dilation works can prevent many patients from expressing frustration when, for example, attempting to read small print on a menu in a dimly lit restaurant. Under-promising and over-delivering is the best strategy, which can be accomplished by being realistic, not necessarily negative. I often mention to patients that 80% of all visual tasks will be achieved with multifocal contact lenses. When you start earlier when a patient has only a low add demand, this percentage is much higher.

Fitting Fees When it comes to fees, you should feel confident appropriately charging for your education, years of experience, expertise, and time. As experts, we deserve to be compensated for both our knowledge and our time. Arrange a mutually agreed-upon course of action prior to the contact lens fitting so that both you and your patients understand what is expected of each other.

Having a backup plan in the event that the lens fit is not successful is also a good idea; this may include modified monovision, monovision, or distance contact lenses with glasses placed over top of the lenses for reading purposes.

STEP-BY-STEP FITTING GUIDE

This step-by-step guide is designed to work with all soft spherical multifocal lens designs (although many multifocal lenses come with specific fitting guides that are also a helpful start):

Step 1 Obtain an accurate refraction. This is the foundation upon which the contact lens fitting process is based. Avoid over-minusing the distance power, and don’t over-plus the power for reading, as this can lead to unnecessarily large add demands. The higher the add demand, the more adaptation is required. A patient who has less than 1.00D of cylinder may be easier to fit compared to those who have higher cylinder prescriptions.

Step 2 Determine the dominant eye. This is necessary for choosing lenses and will help during troubleshooting. In my opinion, sensory dominance testing in which you evaluate the binocular response to plus over each eye is a better indicator of how patients will likely respond to simultaneous vision compared with the sight dominance testing process that involves patients viewing through a triangle formed with their hands to evaluate for alignment.

Step 3 Check patients for any ocular surface issues, such as dry eye, prior to fitting them with contact lenses. Although comfort is less of an issue today due to new developments in technology, this will ensure other factors are not hindering contact lens success.

Step 4 Select the lens modality that you think will work best for each patient, regardless of price. Make your best recommendation, then incorporate the vertexed spherical equivalent of the spectacle refraction, together with the corresponding lens manufacturer’s fitting guide, to choose the initial contact lenses.

Step 5 Apply the lenses and let them settle. Direct patients to look at frames, read a magazine, or survey the office. The more time that patients have to do this, the better the contact lenses will settle and improve accuracy in your vision assessment.

Step 6 Evaluate the fit, vision, and patient perceptions. Ensure that the lenses are centered, aligning the optics of the lens with the center of the pupil and line of sight. When evaluating patients’ vision, keep the lights on and test binocular vision in both distance and near ranges. Additionally, use real-world test methods, such as cell phone screens, watches, magazines, and pill bottles, to further evaluate the lenses.

Success is achieved when all initial complaints have been satisfied, not necessarily when 20/20 vision is achieved. When viewing charts, set 20/40 as the goal and express excitement if patients are able to pass this line. A chart on the wall with no instructions to patients gives an automatic implied expectation that the bottom line is success. When starting early with emerging presbyopes, 20/20 is a much easier goal to achieve than when initiating a fit with a mature presbyope.

Step 7 Now it is time to troubleshoot. Regardless of patients’ complaints (i.e., near, intermediate, or distance viewing), perform a binocular distance over-refraction. Use loose lenses to push plus power in the distance to change the spherical component of the lens. If no improvement is obtained, then try minus power lenses.

Be sure to only make one change at a time. Each lens change requires adaptation. If you are unable to achieve appropriate vision with adjusting the sphere component of the lens, refer to the fitting guide to determine the next step. Do not change the add power despite what your instincts may tell you. Changing the add power is a large shift in the design of the lens and should only be considered when prompted by the fitting guide. If there are still issues remaining at this point, consider the possibility of an incorrect refraction. Evaluating monocular vision at this point may help in troubleshooting refractive errors.

DON’T GIVE UP

If patients do not adapt well to multifocal wear, don’t give up just yet. The abundance of designs on the market today offers alternatives that are worth exploring with a properly motivated patient. Patients may fail in one design and yet do just fine with a different approach. Again, make sure that patients are prepped at the outset about this potential setback and your contingency plans.

Should your patients find that all lens options are poorly suited to their needs, you can consider modified monovision before abandoning multifocal wear entirely. This approach has no exact guidelines; it is more of a trial-and-error approach to fitting lenses when patients’ prescriptions do not follow the usual guidelines and principles. Examples include emmetropic patients who view even a plano lens as a distraction, early presbyopes who may not need two multifocal lenses initially, and astigmatic patients.

Fitting emmetropes with one multifocal lens in the nondominant eye is an easy entry point with presbyopia, but the latter two types of patients are slightly harder to manage. In the case of early presbyopes, even the presence of two low lenses may provide too much add power; instead, place a single-vision lens on the dominant eye and a multifocal on the nondominant eye.

Patients who have astigmatism higher than 1.00D may have difficulties using spherical lenses. For these patients, place a toric lens on one eye and a multifocal lens on the other to provide distance clarity and near support. Those who have high levels of astigmatism in both eyes that cannot be masked with a spherical lens should consider wearing soft toric multifocal, hybrid, GP, or scleral contact lenses.

If patients wearing monovision lenses fail due to a lack of intermediate vision or if the range of vision between near and distance becomes too vast for adaptation, placing a multifocal lens on the nondominant eye can assist with their intermediate vision. You must get creative to help these patients, and perhaps consider options such as using low add powers in the dominant eye and higher add powers in the nondominant eye to prevent blur from two high aspheric lenses. Unfortunately, switching monovision patients to multifocal contact lenses is not an easy task, as they enjoy good distance and near clarity. The best strategy, when possible, is to avoid monovision as the initial choice entirely.

THE END OF A FIT

With so many factors in play during a multifocal lens fitting, it can be challenging to know when patients are fit in the best possible option. The conclusion of the fitting process occurs when there are no other means to adjust the lenses. Patients who are content with their vision may continue to provide feedback until you ask them to stop; thus, it is acceptable to inform patients that you have reached the best level of vision possible with the lenses they are wearing. Remember, you guide and control the process and can decide when to stop.

Above all, you can achieve higher rates of success with multifocal contact lens fittings when patients are properly educated on both the affected visual structures and the fitting process. Including patients on the journey helps them remain involved with their eyecare decisions, ensuring that you are on the same page with the same goals in mind. A comprehensive approach based on effective communication builds stronger relationships between you and your multifocal lens patients. CLS

For references, please visit www.clspectrum.com/references and click on document #255.