Comparison of the Optical Image Quality for Presbyopia Correcting IOLs using Modulation Transfer Function Testing

1. Comparison of the Optical Image Quality for Presbyopia Correcting IOLs using Modulation Transfer Function Testing W. Maxwell, MD, PhD California Eye Institute Fresno, California Financial Disclosure: Consultant & Travel (Alcon Research, Ltd.)

2. Testing Methodology • Study Objective • To compare the image quality of various Presbyopia Correcting IOLs with different designs (accommodative or multifocal; aspheric or spherical) using the modulation transfer function (MTF) testing method and U.S. Air Force 1951 Resolution Target (AFT) testing • Modulation Transfer Function (MTF) Testing • Objective method of measuring image contrast degradation at different spatial frequencies1 • Modified ISO model eye • The standard ISO Model Eye1 configuration incorporates a 35 mm doublet lens to converge light to simulate the refractive power of a human cornea • The model cornea in the ISO Model Eye is an aberration free lens, and is not representative of a typical human cornea with its inherent positive spherical aberration • Thus, a modified ISO model eye, representing an average human cornea, was used in this study Ref 1: ISO 11979-2 Ophthalmic implants – Intraocular lenses – Part 2 Optical properties and test methods, 2000.

3. Optikos Video MTF measurement system 1024 element detector, a 550 nm narrow band filter, and a 20X microscope objective IOLs were mounted in a lens holder under 10 mm of compression, and aligned on the optical axis in a wet cell filled with deionized (DI) water at 35 ± 2 °C with the anterior side of the IOL facing the incident light 3 and 5 mm apertures used to simulate pupil size Green light illuminates a single slit object located on the front focal plane of a 180 mm collimator The collimated light passes through the model cornea and IOL system that simulates the vergence of a human eye CCD Camera IOL Pinhole Target Light Source The optical bench setup MTF Bench IOL Models Tested • ReSTOR SN6AD3 (Aspheric) • ReSTOR SA60D3 (Spherical) • Tecnis ZM900 • Acri.Lisa 366D • ReZoom NXG1 • Crystalens AT-50SE

4. MTF % Frequency (lp/mm) Modulation Transfer Function 5 mm Aperture, Distance FocusSpatial Frequencies of 0 to 100 lp/mm

5. Modulation Transfer Function 5 mm Aperture, Distance Focus, Discrete frequency of 100 lp/mm

6. Modulation Transfer Function 5 mm Aperture, Distance Focus, Discrete frequency of 50 lp/mm

7. MTF of ReSTOR® & ReSTOR® Aspheric IOLs3 mm Aperture

8. Modulation Transfer Function 3 mm Aperture, Distance Focus, Discrete frequency of 100 lp/mm

9. Modulation Transfer Function 3 mm Aperture, Distance Focus, Discrete frequency of 50 lp/mm

10. U.S. Air Force 1951 Resolution Target Test (AFT) U.S. Air Force 1951 Resolution Target Test (AFT) • Optikos Optical Testing System as described for the MTF test • The setup for the AFT test was identical to that of the MTF test, except the single slit object was replaced with the AFT • An image of the AFT was photographed through each IOL • The AFT test includes paired 3-bar target sets used to qualitatively measure resolution efficiency

11. ReSTOR Spherical SA60D3 ReZoom NXG1 ReSTOR Aspheric SN6AD3 Acri.Lisa 366D Crystalens AT-50SE Tecnis ZM900 U.S. Air Force 1951 Resolution Target test 5 mm Aperture, Distance Focus

12. Conclusions • The AcrySof ReSTOR SN6AD3 aspheric IOL produced the highest overall image quality for MTF and AFT testing compared to several presbyopia-correcting IOLs • The Acri.Lisa IOL produced the second highest optical quality, while the ReZoom IOL had the lowest optical quality • Clinical investigation is needed to determine whether superior IOL optical quality demonstrated in optical bench testing results in measurable visual improvements in clinical practice