Multifocal Corneal Excimer Ablations for Presbyopia Guy M

Multifocal Corneal Excimer Ablations for Presbyopia Guy M. Kezirian, MD, FACS Scottsdale, Arizona Carlos Verges, MD, Ph. D Barcelona, Spain AAO 2006 Las Vegas, Nevada November 14, 2006

Disclosures • Presenter is has financial relationships with Wave. Light AG, AMO-Visx, eyeonics Inc. • Owner of Surgi. Vision® Consultants, Inc. and Refractive Consultant Group, Inc. • Some procedures mentioned in this presentation have NOT received FDA approval

Acknowledgments • Theo Seiler, MD, Ph. D – Many of the slides and concepts used in this presentation • AMO-Visx / Bruce Jackson, MD – Many of the slides and concepts used in this presentation

Multifocal Excimer Ablations for Presbyopia • Presbyopia is the most prevalent refractive disorder without a successful treatment • Current treatments include – Spectacles – Monovision (contacts or surgery) • Multifocal excimer ablation procedures • Corneal Inlays • Conductive keratoplasty (CK) – Presbyopic IOL’s

Multifocal Excimer Ablations for Presbyopia • Attempted from early 1990’s (Ruiz) – Ablated around opaque disks placed manually on the cornea • Have been attempted with various ablation profiles since that time • These approaches differ from monovision because they attempt to divide monocular vision (W. Maloney)

Monocular Multifocal Vision • Monovision requires suppression of the image from one eye – Maintains full clarity, brightness of vision from remaining eye • Suppression is common in daily life – Cameras, rear-view mirrors, etc. • Multifocal vision requires partial suppression of image from one eye – Not a physiological condition

Monocular Multifocal Vision • All corneal-based multifocal treatments are pupil-size dependent – Effect varies depends on ambient light, physiologic pupil size • Attempt is to provide adequate near vision and retain as much distance vision as possible – Visual quality is compromised at all distances

Approaches to Multifocal Ablations • Central Steep Island – VISX, Schwind, B&L • Central Steep Annulus – Nidek • Decentered Steep Island – Historical • Asphericity, optimization – Zeiss, Wave. Light

Ablation Techniques For Presbyopic Correction Near Central Near with Peripheral for Far : Luis A Ruiz : Presby lasik Far W Bruce Jackson, ( 2001) Franco Bartoli ( 2002)

Ablation Techniques For Presbyopic Correction Sector Near Zone Far Anschütz, Dausch, Klein, Joly Near (1991)

Ablation Techniques For Presbyopic Correction Peripheral Near Zone Far Near with Central Distance Avalos , Rozakis, Agarwal (PARM- Technique, 1998) G. Tamayo (2000)

Ablation Techniques For Presbyopic Correction “Global Asphericity” Or “Q-Optimized” Near Far Seiler (2005)

Why Central Near? • Miosis with accommodation amplifies effect • Permits a prolate corneal shape – Usually provides the best vision depending on overall optical system • Causes negative asphericity, which also occurs during accommodation – Measured as positive spherical aberration on wavefront

Wavefront Spherical Aberration in Unoperated Myopic Eyes (N = 374) Negative: None: Positive: 6% 51% 43% Data from the US FDA Study of the Wave. Light Allegretto Laser

Presby-LASIK Profile Design Superimposition of a standard correction profile (in this example myopic) with a small diameter hyperopic profile in the center:

Custom Q : profile design: Superimposition of a wavefront optimized correction profile with a highly negative target Q value ( - 0. 6 )

Multifocal Corneas • Advantages: – Ability to read with less defocus at distance – Preservation of better distance Snellen acuity • Disadvantages: – “Light Starved” – Glare, haloes, loss of contrast – Loss of best-corrected acuity – Patient acceptance

Current Clinical Outcomes • Visx • Wave. Light

Visx Multifocal Presbyopia Treatments • Bruce Jackson et al (Canada) • Central steep zone approach • Done in conjunction with hyperopia treatments • BILATERAL (not just for monovision) • 75 eyes in 48 patients, preop spheroequivalent up to 3. 5 D

J 3 or better Monocular Simultaneous Uncorrected Distance and Near Vision 20/25 or better Slide courtesy of Bruce Jackson, MD and AMO-Visx, Inc. 77% of eyes achieve both 20/25 distance and J 3 near or better

Questionnaire Results Percent of subjects Spectacle Use Slide courtesy of Bruce Jackson, MD and AMO-Visx, Inc.

Wavefront Aberrations • Post-op Wave. Scan™ HOA pattern shows central myopic area – Rx Correction Map (in diopters) Case Example: ID#141202 OD 6 M post-op • Dist UCVA: 20/25 • Near UCVA: J 1 Slide courtesy of Bruce Jackson, MD and AMO-Visx, Inc.

Wave. Light Global Asphericity • Theo Seiler, MD, Ph. D and Tobias Koller, MD – Zurich, Switzerland

difference in size of the retinal image fusion 100% 8% 6% 50% 4% 2% 1 2 3 4 5 6 refractive difference / dpt Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD 7 0%

Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Asphericity Basics Prolate shape, Q < 0, slightly myopic Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Presby. LASIK and Asphericity Alternative approach: central steep island (CSI) Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Precondition for a corneal shape that supports near vision in a presbyopic eye Central cornea has higher refractive power compared to peripheral cornea (= prolate cornea) Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Presby. LASIK and Asphericity Optimal corneal shape (R, Q) with a 2. 5 mm-pupil for near objects (0. 4 m) and a 5 mm-pupil for far objects (5 m) • • GLOBAL OPTIMUM (R, Q) myopia of -1. 5 D regarding the central cornea asphericity constant Q = -0. 7 to -0. 9 (hyperprolate) Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Presby. LASIK and Asphericity photoreceptor layer retina 6 mm 4 mm 2 mm pupil size -1 mm -500μm -410μm +500μm -280μm + 70μm Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Presby. LASIK and Asphericity Please note The global optimum shape of the cornea is not a multifocal cornea but an aspheric hyperprolate cornea It does not produce 2 foci and the brain selects the appropriate image like in bifocal IOL's The driving force is the pupil diameter that shifts the focus of the optics The procedure is recommended for ONE EYE (modified monovision concept) Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Presby. LASIK clinical data pilot study, n=15, non-dominant eyes preop sph -0. 5 to +1. 5 D, cyl < 0. 75 D distant VA (100 cd) mean SD range near VA (100 cd) low contrast VA (80 cd) 0. 82 0. 65 (J 3) 0. 58 (pre 0. 62) ± 0. 15 ± 0. 08 ± 0. 12 (0. 2) 0. 5 to 1. 0 J 2 to J 4 Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD 0. 3 to 0. 8

Presby. LASIK and Asphericity monovision -1. 5 D global optimum (R, Q) for near and distant vision CSI with optimal Q distance 5 m pupil 5 mm near 0. 4 m pupil 2. 5 mm Slide courtesy of Theo Seiler MD, Ph. D and Tobias Koller, MD

Conclusions • Multifocal ablations are possible with today’s technology – Issues over ablation shape, contour and location are largely solved • Bilateral treatments seem less likely to succeed than modification of monovision with a multifocal approach • Neural adaptation may be delayed compared with monovision due to intraocular multifocal effect rather than total eye suppression

Conclusions • Procedures seem at odds with current efforts to optimize vision and improve overall wavefronts • Either procedure may be appropriate in some cases but patient selection will be a challenge – Providing realistic preoperative simulations is difficult

Thank You