Several factors key for multifocal IOL success

Keypoints:

Candidates for multifocal IOL implantation should be evaluated to assess their desire for spectacle independence. Accompanying that task, however, is a requirement for the surgeon to understand how the multifocal lens works to determine whether it will meet the patient's needs, said Dr. Masket, clinical professor of ophthalmology, Jules Stein Eye Institute, University of California, Los Angeles.

The screening process also should include assessment for existing conditions that would limit the vision outcome. Dr. Masket recommended avoiding patients with maculopathy, age-related macular degeneration, and epi-retinal membranes. Dr. Wallace noted that he routinely performs optical coherence tomography imaging in addition to his clinical examination in screening for retinal pathology.

"While you can achieve emmetropia in the latter individuals, they will still require spectacles with prisms," he explained.

The two surgeons concurred about the importance of being alert for persons with difficult or negative personalities. In addition, other characteristics are useful in predicting a high risk of dissatisfaction.

"Watch out for patients who say they expect perfection, but be careful as well about implanting the multifocal IOLs in patients with low myopia who are able to read well without glasses. Know when to say no, and be sure your staff is well-educated about the limitations of the procedure and patient warning signs," said Dr. Wallace, medical director, Wallace Eye Surgery Center, Alexandria, LA, and clinical professor of ophthalmology, Louisiana State University, New Orleans.

Presurgical counseling must include detailed information that will enable patients to understand fully the strengths and weaknesses of the multifocal lens, Dr. Masket said.

"I let patients know that, in the FDA trial of the [diffractive lens], 80% of patients never wore glasses and 94% indicated they would choose the same implant again. I also reinforce that nothing is perfect, and I don't hesitate to inform patients about potential nighttime difficulties with respect to halos and that the risk of such problems is fivefold more likely than after monofocal IOL implantation," he said.

Preoperatively, patients also need to be educated about the importance of bilateral implantation to allow cortical summation. The key message for the preoperative patient-physician interaction is to "underpromise and overdeliver," both surgeons said.

"Don't paint yourself into a corner and commit to something patients can be unhappy about later," said Dr. Wallace.

Patient satisfaction depends on achieving an accurate refractive outcome. Dr. Masket said that he aims for emmetropia to minimal hyperopia. Both surgeons noted the importance of an appropriate formula for IOL power calculation and accurate biometry; they expressed a preference for a specific optical biometer (IOL Master, Carl Zeiss Meditec).

Impeccable surgery also is fundamental, they said. Dr. Wallace said that he aims to use the same phaco technique for all of his cataract and refractive lens exchange patients and has been performing a burst hemi-flip technique that is efficient and offers excellent safety for the capsule and zonules because it avoids chopping and cracking. "Do not allow the surgery to be the limiting factor to a successful outcome," he said.

Achieving a good refractive outcome also requires attention to correcting or minimizing astigmatism and may involve adjusting the optical outcome postoperatively to afford patients with optimal vision quality.