What is the main target for all phaco surgeons?

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1 CORRECTION C O OF ASTIGMATISM DURING CATARACT SURGERY Abdallah dllh K. Hassouna, M.D. Sherein S. Wahba, M.D. Ain Shams University 2009

2 Main target What is the main target for all phaco surgeons?

3 Main Target Removal of the crystalline lens ( whether cataractous or not ) with proper IOL implantation combined with other procedures to correct preoperative astigmatism to achieve full emmetropia

4 Astigmatism Natural ldi distribution ib i of astigmatism i 0-1D 45% D 45% >2.5 D 10% Value of minimizing astigmatism To achieve best UCVA Pre-requisite requisite IOLs for multifocal & accommodative

5 Methods of correction of astigmatism at the time of cataract surgery Wound placement Opposite clear corneal incisions Astigmatic keratotomy Limbal relaxing incisions (LRIs) LASIK Toric intraocular Lens

corneal incisions Astigmatic keratotomy Limbal

6 Astigmatism Preoperative evaluation of corneal astigmatism X Use Keratometry, IOL master or elevation based topography Not: refraction (Corneal & lenticular astigmatism) neither Placido based topography (tilt, error in calculation)

$based topography Not: refraction (Corneal & lenticular$

7 Astigmatism < 1 D Steep meridian incision 2 D Opposite clear corneal incisioni i < 3.5 D Limbal relaxing incisions D Staar toric IOL 1-2 D AcrySof toric IOL (T3-T5) D AcrySof toric IOL (T6-T9) Up to 12 D Combinations and piggybacking

3 D Staar toric IOL 1-2 D AcrySof toric IOL (T3-T5) 2.

8 Toric Intraocular Lenses

9 Toric IOLs Advantages: No additional surgical steps Predictable Minimal cataract wound Ideal candidate: Regular astigmatism Astigmatism between D

10 Staar Toric AcrySof Toric Plate Silicon Haptic Single piece hydrophobic acrylic Anterior toric Posterior toric 24 % > 10 rotation Average 4 rotation Usually stabilize within 48h Usually stabilize after OVD removal Corrects: 1.4 or 2.3 Corrects: 1.03, 1.55 or 2.06 D corneal corneal plane Calculator: no SIA compensation Calculator: SIA compensation Longer experience Shorter experience

stabilize after OVD removal Corrects: 1.4 or 2.3 D @ Corrects: 1.03, 1.55 or 2.

11 Complications Decentration Sublaxation

12 Rotational stability Generally, for every 1 of rotation, 3.3% of the IOL cylinder power is lost 30 of rotation may completely negate cylinder power correction of a toric IOL Further rotation potentially increases visual problems for the patients

completely negate cylinder power correction of a toric IOL

13 First Toric IOL Three-piece (PMMA) Toric curve on the concave back surface Implanted through a incision 5.7 mm corneal (Schimizu Schimizu, et al 1992)

14 Second Toric IOL One-piece PMMA lens Over length of 12.5 mm Modified C-loop haptics 5.25 mm round optic (Grabow 1997)

15 Plate haptic First Foldable IOL Foldable silicon Staar Toric IOL Biconvex 6mm optic Sphero-cylindrical l anterior surface Spherical posterior surface

16 Ideal candidate Regular astigmatism Astigmatism between D Prerequisites The cataract neutral Advantages Predictable wound minimal cataract wound should No additional surgical step be astigmatically

5 D Prerequisites The cataract neutral Advantages

17 Complications Decentration Sublaxation Lens rotation and axis shift: 10 results in cylinder reduction of 2/3 20 results in cylinder reduction of 1/3 Partial reduction with up to 30 misalignment

18 Staar Toric OUR AIM To study the best way of reducing PEA during cataract surgery

19 comparing between construction of the wound in the steep meridian, LRIs, and toric IOLs as regards the efficacy, predictability, stability, and safety

20 Patients and Methods This study included 45 eyes of 42 patients with a mean age 53.9 years divided into 3 parts: Part I: Included d 15 eyes underwent cataract t surgery with the incision site on the steep meridian Part II: Included 15 eyes underwent LRIs during cataract surgery Part III: Included 15 eyes underwent cataract surgery with implantation of a Staar Toric IOL

the incision site on the steep meridian Part II: Included 15 eyes underwent LRIs during

21 Calculation of the Toric IOL Power Staar Toric IOL software

22 Staar Toric IOL Inserted through an injector ( mm) Has two marks on should be aligned with the steep axis

25 Visual Outcome Mean % of change of UCVA Part I Part II Part III Comparison between the three parts as regards the mean percentage of change of UCVA

26 Keratometric astigmatism Keratometric Astigmatism Part I Part II Part III Study groups Preop k.astigmatism Postop k.astigmatism 3m Comparisons between the mean preop. keratometric astigmatism, and mean postop. keratometric t astigmatism at 3 months among the study groups

27 Steep meridian LRIs Toric IOL Preoperative postoperative

28 Refractive astigmatism Refractive Astigmatism Part I Part II Part III Study groups Preop R.Astigmatism Postop R.Astigmatism 3m Postop R.Astigmatism 9m Comparisons between the mean preop refractive astigmatism and mean postop Comparisons between the mean preop. refractive astigmatism, and mean postop. refractive astigmatism at 3 months, and at 9 months among the study groups

29 Astigmatism reducing effect Mean % of change of postop. refractive astigm atism D D Comparison between the two astigmatism groups in part III as regards the mean percentage of change of postoperative refractive astigmatism

30 Postoperative Procedure Orientation of the axis of the IOL assessed by: Dilated pupil on SL examination The guide of the Staar software program Rotation of IOL Five IOLs were within 5 degrees of the intended axis Six IOLs rotated 10 degrees Two IOLs rotated 15 degrees One IOL rotated 20 degrees In all cases, the toric IOL remained within 30 degrees of rotation

31 Evaluation of AcrySof Toric IOL As regards the efficacy, predictability, stability, and safety

32 Patients & Methods This study included 12 eyes of 12 patients implanted with Acrysof Toric IOL Mean age of patients was 50.7 years Male Female 75% (3/1) No previous eye pathology or surgery

33 AcrySof Toric IOL Rotational stability STABLEFORCE haptic design Adhesive properties of acrylic material

34 Posterior Surface Toricity

36 Corrective Cylinder options

43 AcrySof Toric IOL calculator

44 Marking of the eye

45 Marking of the eye

47 Precise on- axis placement Gross alignment of the IOL Viscoelastic removal Final alignment of the IOL

51 Visual Outcome

53 Postoperative complication Rotation of IOL Ten IOLs were within 5 degrees of the intended axis Two IOLs rotated 10 degrees In all cases, the toric IOL remained within 30 degrees of rotation

54 Conclusion These preliminary results show that toric IOLs implantation during cataract surgery is effective and a predictable procedure in correction of PEA

55 BUT Cost ineffective (EXPENSIVE)

56 2009 Opposite Clear Corneal Incisions i

57 2009 Opposite Clear Corneal Incisions 2 standard cataract incisions are made 180 apart along the steep meridian

58 Opposite Clear Corneal Incisions Predictable? and effective in providing an enhanced effect over asingle CCI for correcting PEA in cataract surgery Steep axis marked seated at the slitlamp with the patient 2.75 mm incision for astigmatism of 1.0 to 1.75 D 3.2 mm incision for astigmatism >1.75 D

59 Opposite Clear Corneal Incisions No need for special diamond knife No need for expensive IOL Easy reproducible technique

60 Opposite Clear Corneal Incisions Lever and Dahan reported a mean astigmatism correction of 2.06 D with incisions ranging from 2.8 to 3.5 mm In our hand up to 2D of astigmatism correction with 3.0 keratome Stability?

61 Thank you for your attention

Management of Astigmatism in Cataract Surgery

Management of Astigmatism in Cataract Surgery Jonathan B. Rubenstein, M Vice- Chairman and eutsch Family Professor of Ophthalmology irector of Refractive Surgery Rush University Medical Center Financial