Presbyopia Correction During Cataract Surgery with Multifocal Intraocular Lenses

Abstract

Introduction: The first generations of multifocal intraocular lenses (MFIOLs) were designed to provide patients good distance and near vision, but intermediate was not satisfactory. Trifocal, a bifocal of low-add and quadrifocal MFIOLs were invented, offering possibility to correct vision for distance, near, and intermediate tasks. The novel IOL, extended range of vision (EROV), is covering mostly intermediate and distance vision, with lower level of photic phenomena. Patients and methods: We have evaluated visual results in 4408 eyes implanted with different MFIOLs in 12 years period (2004–2016). Postoperative uncorrected visual acuity for far, intermediate, and near was evaluated. Postoperative satisfaction and complica- tion rate and management of complications are presented. Results: In the first generation MFIOLs, almost 70% of eyes gained uncorrected distance visual acuity of 1.0. Uncorrected near visual acuity was J1–J2 in 95% of eyes with diffractive IOLs. Modern MFIOL designs enabled improvement of vision at intermediate dis- tance, without compromising vision at far and near. Conclusion: With the first generations of MFIOLs, good distance and near uncorrected vision was achieved. With novel MFIOLs a very good uncorrected vision was achieved at far, intermediate and near, while with EROV lens, near vision was less satisfactory, but patients had less photic phenomena. IOL is a non-apodized diffractive trifocal IOL with an intermediary 4.5 mm diffractive zone that distributes light to three focal points independent on pupil size. The IOL is a single-piece lens fabricated from a hydrophobic and ultravio-let- and blue light-filtering acrylate/methacrylate copolymer material. This novel diffractive structure has optimized light utilization, transmitting 88% of light at the simulated 3.0 mm pupil size to the retina. The light is split into two, with one half allocated to the distance focus and the other half split evenly between the near and intermediate focuses. The lens design is intended to improve the intermediate vision tasks and increase patient satisfaction, with a third focal point at an optimal intermediate distance of 60 cm, tending to provide more continuous vision. Bifocal diffractive “low-add” IOLs are provided with different add-powers (e.g., +2.75D, +3.25D, +4.00D add), and they have a full diffractive profile on the posterior surface of the optic. The relief height of the diffractive rings is equal in all three models; they have equal light distribution to distance and near regardless of pupil size or add-power. The focal point distance is controlled by the number and spacing of the diffractive rings, and patients have same contrast sensitivity and low-light visual acuity for all add-powers. Extended range of vision IOL delivers a continuous, full-range vision with reduced incidence of halos and glare. It merges two complementary technologies: echelette design which introduces a novel pattern of light diffraction that elongates the focus of the eye, resulting in an extended range of vision, and achromatic technology for the correction of longitudinal chromatic aberration which causes contrast enhancement. It is a diffractive, single-piece, aspheric IOL.