low vision

EVEN WHEN "Nothing More Can Be Done"

You can improve the quality of life for AMD patients.

BETHANY FISHBEIN, O.D., Somerset, N.J.

Hand-held magnifiers are small, portable and fairly inexpensive.

A patient recently told me that his retinal specialist had said: "There's never been a better time to have age-related macular degeneration."

At age 78, no longer able to drive a car, handle his finances or read the morning newspaper, he wasn't convinced.

It's true that more therapies than ever are available to people who have AMD. However, these patients still experience reduced visual acuity and the associated loss of independence that comes with it.

As optometrists, we play an important role in improving the visual efficiency and quality of life of our AMD patients. You don't need to be in a full-time low vision practice to help these patients. As I will explain in this article, with the knowledge you already have, a little bit of time and patience, and a small investment in a "survival kit" of basic low vision aids (see below), you'll have all the tools you need to make a tremendous difference in the lives of these patients.

Keep refracting

Through my experience, I've found that although many AMD patients see a retinal specialist several times a year, some specialists rarely perform a refraction, even though these patients are likely to have refractive changes from a recent cataract surgery or developing cataracts.

I've discovered that the reason some retinal specialists choose not to refract these patients is because a prescription isn't going to "fix" AMD. Although this is true, and these patients' corrected acuity may not be 20/20, improving one's acuity from 20/200 to 20/80, for instance, can make all the difference in the world to these patients. The lesson: Keep refracting these patients.

Refracting a low vision patient is similar to refracting a "normal" vision patient — with a few modifications. If a patient needs to turn his head to use an eccentric viewpoint, he may be more comfortable and give more accurate results with a trial frame refraction. Also the just noticeable difference (JND) will be different in an AMD patient. Someone with 20/200 acuity, for example, won't be able to identify an 0.25D change in lens power. Use trial lenses or a handheld Jackson Cross Cylinder (JCC) lens in this patient to bracket the power and axis.

My guideline for prescribing glasses for a low vision patient is simple: If the patient appreciates a subjective improvement in vision, I prescribe. The astonished reactions of these patients is well worth the additional time and effort of the refraction.

Know the goal

Before prescribing any low vision aids, take the time to discuss the patient's specific goals and what he or she is willing (or not willing) to do to achieve them.

For instance, a patient whose goal is to read stock tables will end up with a very different solution than a patient who is only interested in seeing the television more clearly than before.

In our practice, we send the patient a pre-visit questionnaire. It asks him to define specific vision goals. This saves a significant amount of in-office time and gives patients an opportunity to think about what it is they're hoping to gain from the visit.

We ask our patients to be as specific as possible. Even so, many say that their goal is to "see better." To find out what, specifically, they'd like to "see better," ask all your low vision patients to bring with them to your practice a sample or samples of the things they'd like to "see better." This may include a newspaper, Bible, store receipt, photos, etc. Doing so will enable you to streamline your low vision evaluation to meet each patient's individual needs. Then, while in the exam room, provide the patient with the low vision device(s) you believe may help him achieve better vision.

Other practitioners, such as retinal specialists, will refer many patients to you for low vision evaluations. Several of these patients have no idea what to expect from your assessment. I've discovered that most of these patients, however, hope you'll be able to provide them with "magic glasses" that will restore the vision they had prior to developing AMD. Some, you'll find, will settle for nothing less.

Therefore, it's critical you educate your low vision patients that low vision aids will not repair their eyes or restore their lost vision. Explain to these patients that their vision is limited by their eye condition — and that no low vision device, contact lens, surgery or eye drops are going to "fix" their AMD. Now, explain that low vision devices provide magnification for distance and near objects and increase contrast, allowing the patient to use his remaining eyesight to see smaller things than he could see before.

I've found that once patients understand this, they're more willing to try a low vision device or aid that may help them, and less likely to be disappointed in the result.

Magnify

Magnification for distance vision is based on the patient's acuity and size of the target the patient desires to see. Hand-held monocular telescopes are small and portable, come in a variety of powers and allow for the quick spotting of distance objects. For patients who want to use their distance magnification for extended time periods, consider prescribing spectacle-mounted telescopes. Bioptic telescopes are useful for patients who want to use their telescopic glasses full-time. (See this month's Practice Pulse regarding a new telescopic lens.)

For near vision, the simplest way to magnify is by increasing add power. Many practitioners are hesitant to prescribe an add power greater than +2.50D or +3.00D, perhaps because doing so requires a bit of extra coaching in terms of helping the patient to acclimate to the lens. But microscopic spectacles with powers up to +40.00D are available. High add powers provide magnification by allowing the patient to hold the reading material close, which increases the size of the image on the retina. For patients who don't mind holding their reading material close, a high-powered spectacle can be a convenient and comfortable method of magnification.

For patients unable (or unwilling) to tolerate the close working distance of a high-powered spectacle for near vision, or for tasks that won't allow the patient to hold the material a few inches away, consider a hand-held or stand magnifier.

You can quickly demonstrate varying levels of magnification by showing the patient stand magnifiers in varying powers. Because stand magnifiers rest directly on the reading material, they don't depend on a patient's ability to focus the device. These work well for patients doing extended reading or for those who have a hand tremor.

Hand-held magnifiers are small, portable and fairly inexpensive. Also, they're familiar to most patients — we find many patients have already purchased a magnifying glass on their own. Educate these patients that as optometrists, we have access to stronger magnifiers than those available in stores, and demonstrate these magnifiers, as patients may achieve better visual acuity with a nonstore-bought magnifier.

Closed-circuit televisions (CCTVs) (or other forms of digital magnification) are also an important part of your low vision evaluation. Although these are more costly than optical low vision devices, they provide a high level of magnification, a wide viewing area and the ability to enhance contrast on all types of reading material, such as magazines or newspapers. I've found that low vision patients who want to read easily and comfortably do extremely well with this type of device. Some CCTV manufacturers offer a discounted price on a "demo" unit or may even place a CCTV in your office at no charge, so you can demonstrate it to patients.

Once you find a level of magnification that meets your patient's needs, demonstrate the same power level in a spectacle, hand-held magnifier, stand magnifier and CCTV. The patient will let you know which device(s) work(s) best for him. Understand that one vision aid may not work for all tasks — just like patients need different glasses for different purposes, they'll likely need several low vision aids as well.

Be realistic

In a multidisciplinary low vision setting, you can prescribe a low vision aid that may require extensive training, knowing that a network of therapists and rehab teachers will coach the patient to succeed with the device.

Private-practice primary-care O.D.s often don't have this luxury. A patient's performance with the device at the practice is a good indication of how he'll perform with it at home. If a patient is frustrated, and not able to use the aid immediately, it's unlikely he'll be able to succeed with it at home.

Again, demonstrate low vision aids to patients, and allow them to decide which will be most useful. Be encouraging, but listen if patients tell you they don't have a need for a specific vision aid.

Patients find it both helpful and convenient when they can try devices before purchasing them. Many clinics have a "loaner program," in which patients can try vision aids in real-life situations, such as at the grocery store. This is difficult to monitor and expensive to maintain in a private practice. You can avoid a loaner program by having a return policy on low vision devices.

If you can't help a patient with the equipment you have, tell the patient. If you're comfortable, order a different device for the patient to try. If not, refer the patient to someone who can help him.

While today's AMD patients have more treatment options than ever before, none of these options are "cures." These patients still experience reduced vision, often discovering they are unable to do things they were able to do before. By combining your optometric knowledge with some essential low vision equipment, you can offer solutions that can improve your patients' quality of life by keeping them active and independent. OM

Dr. Fishbein owns the Low Vision Center at Robert Wood Johnson University Hospital in New Brunswick, N.J., and owns Somerset Eye Care in Somerset, N.J. E-mail her at drbeth any@somerseteyecare.com.