Management of Corneal Astigmatism with Toric IOLs Optimizing

Management of Corneal Astigmatism with Toric IOLs: Optimizing Outcomes Adam Goddard, D. O. Comprehensive Ophthalmologist Associated Eye Care Stillwater, MN

Financial Disclosures • None

Objectives • Understand clinical considerations for Toric IOLs • Review of Toric IOL design and ranges of astigmatism correction • Application of preoperative and intraoperative technology for astigmatism management • Clinical measurements of astigmatism • Verion™ Image Guidance System • Pearls for optimizing visual outcomes

Overview • Coexisting cataract and corneal astigmatism • Correcting astigmatism in the IOL plane

IOL Design: Technis Toric (AMO)

Technis Toric (AMO) AMO Model ZCT 150 ZCT 225 ZCT 300 ZCT 400 IOL Plane (D) 1. 50 2. 25 3. 00 4. 00 Corneal Plane (D) 1. 03 1. 55 2. 06 2. 75 Range of Correction 0. 75 to 1. 50 to 2. 00 to 2. 75 to 3. 62 (D)

IOL Design: Acrysof Toric (Alcon)

Preoperative Assessment • Regular corneal astigmatism • • Corneal topography IOL Master or Len. Star Ks Manual Ks Refractive status • Corneal vs. lenticular astigmatism • Lenticular offset of corneal astigmatism

Preoperative Assessment • Keratometry instruments • Len. Star, Verion, IOL Master, Topography, manual Ks, auto Ks • K readings should vary by no more than 0. 5 D • Steep axis for K readings should vary by no more than 10 degrees

Preoperative Assessment • Pearls for technical component • Input for post-LASIK (myopic vs. hyperopic) very important to avoid errors • Flag post-refractive patients • Clear communication between surgeon, ASC, advanced lens technology technician, and surgery schedulers is critical • QA process

Preoperative Assessment • Intact capsular bag and zonules • Continuous curvilinear capsulotomy • Careful consideration with prior corneal refractive surgery • Caution with pre-existing ocular disease • KCN, Fuchs dystophy

Preoperative Assessment • Posterior Corneal Astigmatism • Previous calculations assume anterior and posterior corneal curvature have a constant ratio • Dr. Doug Koch (Baylor) found posterior corneal curvature varies widely among individual patients • Ignoring posterior corneal astigmatism may yield incorrect estimation of total corneal astigmatism

Preoperative Assessment • Posterior corneal astigmatism (cont) • Average posterior cornea has slight plus power in the horizontal meridian, creating against-therule refractive astigmatism • Using anterior corneal measurements alone can result in: • Overcorrection of with-the-rule astigmatism • Undercorrection of against-the-rule astigmatism • Baylor Normogram

Preoperative Assessment • Online Toric Calculators • Alcon Toric Calculator • http: //acrysoftoriccalculator. com • Barrett Toric Calculator • http: //www. ascrs. org/barrett-toric-calculator • AMO Tecnis Toric Calculator • http: //www. tecnisiol. com/us/physician/calculation

Surgery • Capsular integrity • Orienting and marking eye for appropriate axis implantation • Careful placement of toric IOL and removal of viscoelastic

ORA with Verifye+ • Validate / refine surgical plan • Refractive information, including IOL power, cylinder, and axis of astimatism • Account for anterior and posterior corneal astigmatism • Minimize undesired residual astigmatism postop

Case Presentation • 73 y. o. F with symptomatic cataracts OU • Halos/glare, blurring at distance > near • Patient desires best uncorrected distance vision • Current Glasses • -4. 50 +3. 75 x 010 = 20/40 • -4. 25 +3. 00 x 168 = 20/40 BAT = 20/400 BAT = 20/100 • Exam • 2+ NSC / 1+ ACC OU • No other pathology on SLE/DFE

Case Presentation • Post-op Outcome • Very happy with subjective improvement and quality of uncorrected distance vision • VAsc: 20/25 OD, 20/20 OS • MRX: • -0. 25 +0. 75 x 045 = 20/20 • -0. 25 sph = 20/20

Toric Alignment • Axis Assistant App

Toric Alignment • i. Handy Level

Residual Refractive Error after Toric IOL? • http: //astigmatismfix. com • • Berdahl-Hardten Manifest refraction in plus or minus power Enter the axis of the current toric IOL Calculate • No rotation, exchange

Future • Multifocal/Toric IOL • Awaiting FDA approval in the US • November 2014 • US FDA’s Ophthalmic Devices Advisory Committee recommended FDA approval of Re. STOR Multifocal Toric IOL • Currently approved in Europe, Canada, Australia, Japan, and many countries in Central and South America

Summary • A wide range of astigmatism correction is now available with toric IOLs • Advancements in technology, including Len. Sx and Verion/Verifye+, have improved surgical precision • Attention to preoperative and intraoperative detail can help achieve optimal outcomes • Measurements should make sense • Consider posterior corneal astigmatism

Questions? • Thank You!

References Visser N et al. J Cataract Refract Surg. 2011; 37(8): 1394 -1402. Koch DD et al. J Cataract Refract Surg. 2012; 38(12): 2080 -2087. Osher RH. J Cataract Refract Surg. 2010; 36(2): 351 -352. https: //www. myalcon. com/products/surgical/verion-guided-system/index. shtml https: //www. myalcon. com/products/surgical/ora-system/index. shtml http: //www. telescope-optics. net/images/eye_optics 2. PNG