Fully diffractive presbyopic IOL enhances predictability of visual outcomes

The latest incarnation of the lens offers full range of vision at all distances, surgeon says.

An aspheric presbyopia-correcting IOL yields full range of vision with high spectacle independence and few complications, according to an investigator of the lens.

Elizabeth A. Davis, MD, FACS, shared anecdotal observations of the Tecnis multifocal IOL (Abbott Medical Optics) in an interview with Ocular Surgery News.

“I have been extremely pleased with that lens,” Dr. Davis said. “This continuum of vision, from distance to intermediate to near without any gaps, has been really pleasant. I’ve had very positive feedback from patients.”

The IOL’s visual outcomes are comparable to those of LASIK and more accurate than many other multifocal IOL designs, Dr. Davis said.

“When I’m going to do a refractive procedure to try to deliver refractive results to a patient, I’m hoping to get the same wow effect that I get with LASIK,” she said. “With previous technology, I didn’t feel that that existed. I didn’t really get a wow effect and I also didn’t feel that I got the predictability that I was looking for.”

Elizabeth A. Davis

The U.S. Food and Drug Administration approved the Tecnis multifocal IOL in January 2009. A one-piece version of the lens for cataract patients with and without presbyopia was approved in March 2010. Dr. Davis served as an investigator in the FDA clinical trial for the original Tecnis multifocal IOL.

Enhanced quality of vision

The Tecnis multifocal IOL is made of a hydrophobic acrylic material that reduces chromatic aberration and enhances contrast sensitivity, Dr. Davis said.

“I’ve never had any issues with the material,” Dr. Davis said. “It’s very biocompatible. It unfolds gently in the eye. When you YAG it, it doesn’t pit. It’s just very quiet and clear in the eye.”

The IOL’s fully diffractive surface offers pupil independence, Dr. Davis said.

“It is a pupil size-independent lens,” she said. “You don’t need to worry about measuring preoperative pupil size or the effect of that on vision in various lighting conditions. I haven’t found any significant complaints from my patients on difficulty in various lighting conditions.”

Most patients implanted with the Tecnis multifocal IOL rate glare and halo severity at about 2 on a scale of 0 (no glare or halos) to 10 (severe glare or halos), Dr. Davis said.

“I’ve never had to remove a Tecnis multifocal for any reason: glare or halos, unpredictable outcome, or poor quality of vision,” she said. “I’ve had to remove every other presbyopic lens at least once from some patient’s eye, be it my own patients or other surgeons’ patients’ eyes.”

In addition, nearly 100% of patients are spectacle-independent for all activities after receiving the lens, Dr. Davis said.

“A couple of them have required LASIK enhancements, but that was known preoperatively because they had preexisting astigmatism,” she said. “We knew we were going to treat postoperatively with LASIK, but once that was done, [the patients] were spectacle-free.”

Maximizing predictability

Optimizing the ocular surface and ensuring the accuracy of preoperative keratometry readings help maximize the accuracy of refractive targeting, lens centration and optical outcomes, Dr. Davis said.

“Preoperatively, you can feel confident in your targeting,” she said. “Intraoperatively, there are no problems with delivery of the lens, centration of the lens — it centers beautifully. And then postoperatively in terms of the optics of the lens, the quality of vision is far superior, in my experience, to other multifocal lenses.”

Patients are asked to refrain from wearing contact lenses for several weeks before surgery to ensure the accuracy of keratometry measurements, Dr. Davis said.

“With the Tecnis multifocal, if you have good preoperative measurements of your keratometry and your axial length, you can feel very confident that you’re going to get on-target outcomes,” she said.

Dr. Davis’ practice uses immersion A-scan ultrasound measurement for Tecnis multifocal IOL recipients, but biometric measurement with the IOLMaster (Carl Zeiss Meditec) is equally effective, she said.

Dr. Davis said she prefers the three-piece Tecnis multifocal IOL over the newer one-piece model.

“It’s not that I’m opposed in any way to a one-piece,” Dr. Davis said. “It’s just that I’m used to the three-piece and like the delivery and centration of it.” – by Matt Hasson

• Elizabeth A. Davis, MD, FACS, can be reached at Minnesota Eye Consultants, 9801 DuPont Ave. South, Bloomington MN 55431, U.S.A.; +1-952-567-6067; e-mail: eadavis@mneye.com. Dr. Davis is a consultant to Abbott Medical Optics.