COMANAGEMENT

Roadmap for IOL Success

Develop beneficial comanagement relationships with both patients and surgeons.

by Steven Chang, M.D., San Francisco, Calif.

You've just examined Mr. A., a 68-year-old male. Over the years, you've monitored his cataracts. On this visit, he tells you his vision "bothers" him, and he now has difficulty with some routine tasks. Upon further examination, you notice his cataracts require surgery.

Earlier in the day, you saw Mrs. B., a 52-year-old business professional, who complained about the inconveniences of wearing glasses. She is a hyperopic presbyope who did not rely on glasses until very recently, but now depends on them for all activities.

The dilemma

Each of these patients seeks your help as their primary-eye care professional to guide them into the next step — intraocular lens (IOL) implantation. But to whom do you send them? Do you give them a couple of business cards of local ophthalmologists? Are you confident that these surgeons can help? Are you content to send them to Dr. C., who will treat the problem and then refer the patient back to you? Or, do you want to be intimately involved in your patients' care and comanage them? If you choose comanagement, how do you establish this relationship with a surgeon?

Find the right surgeon

The first step in establishing a successful comanagement relationship is to find the right surgeon. During your search, you may find many surgeons who will not comanage. You will also find, however, some who welcome the opportunity to "team up" with you. If you're new to the area, check with your local colleagues for recommendations. Ultimately though, it will be your decision.

Look for someone with whom you're comfortable. This surgeon must have good communication skills — a key element in comanagement.

Surgical skill is important. Skilled surgeons are revealed through their results and their patients' word of mouth.

Finally, choose a surgeon who has knowledge and experience with the latest IOLs so you can ensure your patients are fit with the most appropriate lens. You will find many ophthalmologists have limited experience with the new multifocal, toric and aspheric IOLs. (Furthermore, most don't perform refractive lens exchanges.)

Additionally, you must have a basic knowledge of the current IOLs on the market, so you can educate your patients and facilitate the proper lens selection.

The following three sections describe the latest IOLs:

Presbyopic IOLs

Since their FDA approvals a few years ago and the Medicare shared-billing ruling, the presbyopic lens market has grown and will continue to do so for years. For the first time, we have IOLs that are capable of providing a full range of vision to patients, mimicking their younger crystalline lenses. Currently, two multifocal IOLs [ReSTOR (Alcon) and ReZoom (Advanced Medical Optics)] and one accommodating IOL (Crystalens [Eyeonics]) are on the U.S. market. Countless more are in the research and clinical trial pipeline.

The ReSTOR IOL is an acrylic, single piece lens with a 3.6mm apodized diffractive central zone for near vision and an outer ring for distance. As with all multifocal IOLs, the Re-STOR is dependent on the normal dilation of the pupil — providing near vision in bright light (small pupils) that can diminish in dimmer settings (larger pupils). This IOL tends to provide strong distance and near vision with good intermediate vision.

FDA clinical trials showed that 80% of patients fit in this IOL didn't need spectacles for any task after surgery, and 20% needed them only occasionally.

The ReZoom IOL is a second-generation acrylic three-piece refractive lens. It utilizes a multizonal multifocal design to distribute light over five distinct optical zones, providing near, intermediate and distance vision. This IOL tends to provide strong distance and intermediate vision with good near vision.

Ninety-two percent of patients did not need spectacles for any task or used spectacles occasionally, according to FDA clinical trials.

Multifocal lenses do not rely on mechanical movements to function. Rather, the IOL companies manufacture the zoom into the lens. While this tends to result in more reliable outcomes after surgery, it may produce glare and haloes in some patients. The amount of light phenomenon varies from person to person, but invariably ceases through a process called cortical adaptation.

The Crystalens (Eyeonics) is the only accommodating IOL with FDA approval. It is a monofocal, square-edged, silicone lens with flexible hinges on both sides that support the lens in the capsular bag and allow it to change positions. As the lens is monofocal and does not rely on splitting available light into different focal points, the issues of glare and haloes are greatly reduced. The lens tends to provide strong distance and intermediate vision with good near vision.

FDA clinical trial results of the Crystalens showed that about 85% of patients fit in this IOL were able to see at all distances without the aid of glasses or contact lenses.

Given each IOLs' strengths and limitations, the surgeon must have extensive experience in custom matching the right IOL to the right patient. I utilize patient questionnaires and significant discussions with the patient to decide upon a course of action. I will mix and match the lenses to provide the fullest range of vision or utilize certain IOLs based on a patient's pupil size, retinal pathology or personality.

Toric IOLs

If your patient has significant corneal astigmatism, wants crisp distance vision and doesn't mind wearing readers, the toric IOL is a fantastic option and more accurate than a limbal relaxing incision or astigmatic keratotomy. The Acrysof toric (Alcon) is a monofocal, acrylic, natural IOL with posterior toricity that can correct up to 3.00D of astigmatism.

FDA clinical results showed that 97% of patients with bilateral implantation of the Acrysof toric IOL achieved spectacle freedom at distance. Results also showed minimal shifting of the IOL once implanted.

Monofocals and aspherical IOLs

For patients who want IOLs covered by traditional insurance or who are not candidates for other lenses, the wavefront-guided aspheric IOLs are an excellent option.

Three aspheric lenses are currently on the U.S. market: IQ (Alcon), Tecnis (AMO) and the Sofport AO (Bausch & Lomb). Both the IQ and Tecnis provide negative spherical aberrations, while the AO does not add any spherical aberrations. On average, the normal human cornea has some degree of positive spherical aberration that is offset by the negative spherical aberration present in a young crystal-line lens. As the lens changes with age to form a cataract, the spherical aberrations become more positive, adding to the positive corneal spherical aberrations. This leads to a decrease in overall image quality and contrast sensitivity.

Traditional spherical IOLs add positive spherical aberrations, whereas two of the three aspheric IOLs add negative ones, offsetting the corneal aberrations to provide an optimal visual system. The AO lens does not add any spherical aberrations, thereby leaving some positive aberrations that some surgeons feel increases depth of focus.

FDA clinical trials have demonstrated strong night vision and image quality with the aspheric IOLs.

Diagnosis and referral responsibilities

Your first role in comanagement is to perform a comprehensive exam, so you can diagnose the visual problem. Following this, you should discuss some of the available IOL options. Still, avoid getting into a detailed discussion, as the surgeon may decide on a different course of action, based on results from his/her evaluation. You don't want the patient to be confused, as this can lead to distrust.

Next, you should fax a referral sheet (exam sheet, note, formal letter), or simply place a phone call to the surgeon to provide the patient's history, so he/she can provide the patient with the most appropriate options.

Comanagement works well because we understand that you are the patient's primary-care giver and know the patients better than we do. Therefore, you are the patient's advocate. If you feel strongly that your patient is not a good candidate for a multifocal lens, voice your concern. If your patient changes eyeglass prescriptions several times a year and is still not satisfied, which may indicate the need for a surgical solution, notify the surgeon. Also, notify the surgeon of underlying pathology so he can investigate further. Open lines of communications assure the best care.

Postoperative care pearls

Arrange with your surgeon a postoperative care plan and schedule of visits. As you rely on the surgeon to provide optimal surgical care, he/she relies on you to provide optimal postoperative care. If you have any questions or concerns during your examination, contact your surgeon for advice or to see the patient.

Some pearls to remember regarding postoperative management of the presbyopic IOLs:

• Best results are on ~plano prescription.

• 0.75 D or more of astigmatism degrades visual quality and may cause blur, ghosting and halos.

• Patients may need LASIK fine tuning (lens shift during healing/astigmatism).

• Monitor for posterior capsular opacification. Dry eyes are very sensitive to any opacities or surface irregularities.

• Aggressively monitor for cystoid macular edema.

• Beware of glare and haloes with multifocal lenses. They can can last for up to a year but go away with cortical adaptation.

• Some patients will need specs for extended reading and/or intermediate tasks.

• Have patience. Some patients need more time to adapt … but they all eventually do and are happy.

Remember always that the patient's care comes first. Comanagement with the right players can create a successful and lasting relationship that satisfies the O.D., the M.D. and the patient. OM

Dr. Chang is a fellowship-trained anterior segment and refractive surgeon. He is the director of cataract and lens surgery at Pacific Vision Institute (PVI) in San Francisco, Calif. E-mail him at steve@pacificvision.org.