A new +2.5 D add version of a multifocal IOL features a redesigned optic that enhances visual function at intermediate and distance and delivers excellent visual quality.
Dr Francesco Carones described the design and attributes of the acrylic aspheric apodized diffractive multifocal IOL (AcrySof IQ ReSTOR +2.5, Alcon Laboratories, Fort Worth, Texas, USA). He also discussed his experience with implanting the lens bilaterally or in a mixed approach, using the +2.5 D add multifocal IOL in the dominant eye and the near distance-optimized +3 D add multifocal IOL in the non-dominant eye.
Compared with the +3 D version of the apodized diffractive multifocal IOL, the +2.5 D lens distributes more light energy for distance. It has a larger central zone with a refractive versus diffractive design, noted Dr Carones, medical director, Carones Ophthalmology Centre, Milan, Italy.
"The +2.5 D add multifocal IOL provides distance vision quality and contrast sensitivity performance that is comparable to a monofocal IOL, intermediate vision and night vision quality that is better than with the +3 D add multifocal IOL, and good functional near vision exceeding that achieved with a monofocal IOL," Dr Carones said.
"With these features, the +2.5 D add multifocal IOL is especially well-suited for patients seeking a range of uncorrected vision better than that achieved with a monofocal IOL, who are concerned about quality of vision, but whose primary vision needs are for distance and intermediate tasks," he added.
Because the +2.5 D and +3 D versions of the multifocal IOL each have unique benefits, decisions on whether to implant one or the other bilaterally or both in a blended approach depend on the patient's visual needs, Dr Carones noted. The selection is guided by patient responses to a lifestyle questionnaire that is designed to determine an individual's vision preferences and goals. Other factors considered include the patient's age and height, as generally patients who are younger or taller may do better with bilateral implantation of the +2.5 D IOL.
"However, with proper IOL selection, satisfaction has been high, whether patients [undergo implantation] bilaterally with either lens or... a blended approach," Dr Carones said.
Bilateral or blended?
Thirty-six patients underwent implantation with a blended approach, receiving the +2.5 D add IOL in the dominant eye and the +3 D add IOL in the non-dominant eye. In binocular UCVA testing, all achieved 20/20 or better at distance, whereas 89% saw 20/20 or better at intermediate. Binocular near UCVA was 20/32 or better in all eyes and 20/20 in 75%.
The +2.5 D add AcrySof IQ ReSTOR multifocal IOL will be launched later this year in Europe. It has not yet been approved by the FDA.