1. Evaluation & Surgical Correction of Astigmatism
Jean Luc Febbraro MD
Rothschild Foundation
Paris
France

2. Evaluation & Surgical Correction of Astigmatism
Financial disclosure
Alcon Laboratories: C, Croma: C
Bausch & Lomb Surgical: C,L

3. Surgical Correction of Astigmatism
Evaluation & Principles
Prevalence & Evolution
Cataract incisions SIA

4. Evaluation of Astigmatism
K-readings
2mm central
Topography
Placido, Scheimflug (cornea > 2mm)
Aberrometers (cornea, internal)
Refraction
Total astigmatism (subjective, objective)

5. Evaluation of Astigmatism
Topography (placido)
Precise measurement
Magnitude, axis
Symmetry
Regularity
Detection
K. fruste
Pellucid Deg.

6. Evaluation of Astigmatism
Aberrometers (Hartman-Shack, OPD)
Precise measurement
Lower order ab. (Sph, cyl.)
Higher order ab. (coma, trefoil, sph. aberrations)
Distinction
Total, internal

7. Evaluation of Astigmatism
Refraction (Subjective, objective)
Perfect match required
Subjective
(Sph, cyl)
Objective
(Sph, cyl & HOA)
Enable WF ablation

8. Astigmatic Correction & Cataract Patients
Surgical options:
Incisional techniques
LRI, AK
Toric IOLs
Laser vision correction
PRK, LASIK

9. Astigmatic Correction & Incisional Techniques
Principles:
The cornea flattens over an incision
Transverse incisions increase the radius of curvature in one meridian only
The flattening effect increases as incisions approach the visual axis

10. Astigmatic Correction & Incisional Techniques
Coupling:
The flattening effect of a transverse incision is associated with a steepening effect 90° away.
Coupling ratio tend to be one to one.
The spherical equivalent remains unchanged.

11. Astigmatic Correction & Incisional Techniques
Principles:
Incisions are always placed on the steep meridian.
The longer and deeper the incision the greater the effect.
The older the patient the greater the effect.

12. Astigmatic Correction with LRI
LRI / PRI
Placed on the steepest meridian
Located at the limbus ( mm OZ) 44 42

13. Astigmatic Correction with LRI
Principles
Flatten the steepest meridian
Steepen the axis at 90°
Coupling ratio 1:1 42 43 44 43

14. Astigmatic Correction: LRI / AK
LRI: pros
Less irregular astigmatism
Less chance of perforation
Convenient technique
Easy to perform
Intraoperatively

15. Astigmatic Correction: LRI / AK
LRI: cons
Limited astigmatic correction
Regression
Variability of results

16. Astigmatic Correction: LRI
Instruments: simple kit
Axis marker
0.12-caliber forceps
Diamond knife
Preset (600 microns)
Micrometer

17. STUDY 46 eyes, 30 patients (age: 72 + 10 A) 3.2 mm CCI, Steep axis
Preset 600 µ diamond knife
Limbal relaxing incisions
Preop Corneal Astig.: D (0.75 to 3)
Follow up: 6 M

18. Results: Astigmatism pre / postop
Corneal Astigmatism (D)

19. LRIs: Tips & Tricks Placement of incisions Axis Constant orientation
10° off: -33%
15° off: -52%
Constant orientation
Constant depth
Preset 600µ knife
Micrometer knife set at 90% thinnest pachymetry
Steep axis +++

20. Astigmatic Correction withToric IOLs
Reduction of Astigmatism
SN60T3 = 1.5D (1D)
SN60T4 = 2.25D (1.5D)
SN60T5 = 3.0D (2D)

21. Astigmatic Correction withToric IOLs
FDA Data
92% 20/40 or better
Mean residual astigmatism: 0.60 D
50% less than 0.5D of residual postop astigmatism
97.6% rotated less than 15 degrees

22. Astigmatic Correction with Laser
Laser Vision Correction:
Precise correction of astigmatism
Correction of spherical component
Check MR and WF refraction

23. Astigmatic Correction with Laser
Netto et al, AJO 2006;141:

24. Laser Astigmatic Vision Correction
Refractive patients: primary choice
PRK
LASIK
Excellent accuracy (sphere & cylinder)
Constant technological improvements

25. Laser Astigmatic Vision Correction
All types of regular astigmatisms
Simple, compound myopic astig.
Flatten the steepest meridian
Simple, compound hyperopic astig.
Steepen the flattest meridian
Mixed astig.
Combine both principles

26. Cyclotorsion & Astigmatic Correction

27. ACE Iris Recognition SRET DRET
Static Rotational ET Dynamic Rotational ET
Compensation between Intraoperative compensation
upright / supine position
Texte

28. Cyclotorsion Study Eyes Mean Degree Movement Other Febbraro et al.
JCRS, 2010 70 º
up to 14º
Swami, Steinert et al, AJO, 2002
240
4.1º + 3.7º
8% with over 10º of movement
Smith, Talamo, Assil, JCRS, 1994 50 -
25% over 7º of movement (up to 16º)

29. Results Cyclotorsion: Static (SRET) / Dynamic (DRET) ACE SRET DRET
Mean ° °
Range ° °
Fondation A. de Rothschild
Paris
Jean-Luc Febbraro MD

30. ACE Mean Static (SRET) / Dynamic (DRET) Fondation A. de Rothschild%
Cyclotorsion
Fondation A. de Rothschild
Paris
Jean-Luc Febbraro MD

31. ACE Mean Absolute Amplitude (DRET) Fondation A. de Rothschild
DRET Amplitude (°)
Fondation A. de Rothschild
Paris
Jean-Luc Febbraro MD

32. Fondation A. de Rothschild
Conclusion
Surgical correction of astigmatism is a reality
Mandatory to optimize uncorrected vision
Refractive and cataract patients
Numerous surgical options
Fondation A. de Rothschild
Paris
Jean-Luc Febbraro MD

33. Prevalence and evolution
Of astigmatism
Clinical significance
Accurate eye care
IOL manufacturers (SA , Cyl.)
Valuable information for cataract & refractive surgeons

34. Prevalence and evolution
Of astigmatism
Astigmatism evolution with age
Age / Ast.
2654 patients %
Mean
20-30 years
40%
1.20 D
70-80 years
72%
1.30 D
Prevalence of astig. increases with age.
Ferrer-Blasco T. et al. JCRS 2008; 34:

35. To evaluate Astigmatism Distribution and Evolution in Adult Patients
STUDY
To evaluate Astigmatism Distribution and Evolution in Adult Patients
Retrospective study
500 eyes of 276 patients
Autorefractometer refraction & keratometry measurements
Mean interval: /-2.92 y (min 5-16 max)

36. RESULTS Mean ocular astigmatism 0.95 +/- 0.77 Mean corneal astigmatism
Mean age /
Age min- Age max
37-90
Gender: Male / Female
182 M / 318 F
Mean sphere
/- 3.20
Sphere min-max
Mean ocular astigmatism
0.95 +/- 0.77
Ocular astig. min-max
Mean corneal astigmatism
1.14 +/- 0.40
Corneal astig. min-max
Mean flat K (K1)
/- 1.39
Mean steep K (K2) /
Nous avons etudie 500 yeux…

37. RESULTS Astigmatism Distribution Magnitude ≤0.5D 35.8% 33.8% 0.75 - 1D
Ocular Astig.
Corneal Astig.
≤0.5D
35.8%
33.8% D
36.6%
33.4% D
20.8%
23.8%
> 2D
6.8%
8.2%
Distribution de lastig total et corneenselon sa puissance , on voit que le 1 tiers des ….

38. RESULTS Astigmatism Evolution visit 1 visit 2 -0.02 OCULAR AST.
CORNEAL AST.
SPHERE
L evaluation de la sph du cyl total et corneen lors de la 2eme visite montre que….
-0.02

39. Astigmatism Evolution
RESULTS
Astigmatism Evolution
Age Groups
Cylinder
Axis
< 50
0.19 +/- 0.64D
6 +/- 17°
50-59
0.24 +/- 0.71D
12 +/- 20°
60-69
0.31 +/- 0.75D
6 +/-17°
> 70
0.28 +/- 0.89D
5 +/- 15°
ATR shift over 8 years
0.26 D

40. Astigmatism Evolution
Age Groups
Study
500 eyes
Reykjavic Eye Study* 757 eyes
< 50
0.19 +/ D
50-59
0.24 +/- 0.71D
0.09 +/ D
60-69
0.31 +/- 0.75D
0.13 +/ D
> 70
0.28 +/- 0.89D
0.22+/- 73°
All Groups
O.26 D over 8 years
0.13 D over 5 years
* E. Gudmundsdottir, A. Arnarsson, F. Jonasson. Five-year refractive changes in an adult population; Reykjavik Eye Study. Ophthalmology 2005;112, 672–677.

41. Astigmatism in Cataract Patients
Knowledge of prevalence and evolution of astigmatism is valuable information
35% negligible astig.
35% 0.75 – 1 D
30% > 1 D 7% 2 D
Mean magnitude +/- 1 D in adults, tends to increase with age
ATR axis shift (0.13 – 0.26 D) over time, particularly in older patients

42. Cataract Incisions Introduction
Trend
Size
Standard 3-mm incision
Mini mm incision
Micro sub 2-mm incision
Placement
Scleral to limbal / clear corneal incision
Superior to temporal approach
Texte

43. Cataract Incisions Choice Factors
Size
IOL implantation
Monofocal, Multifocal, Accomodative, Toric IOLs
Phaco platform
Phaco and I/A probes & sleeves
Location
Scleral to limbal / clear corneal incision
Superior to temporal approach
Texte

44. Cataract Incisions Astigmatic Effects
Astigmatic change
Incision size
Distance from visual axis
Axis placement
Astigmatic change evaluation
Algebraic method (magnitude of ast.)
Vector Analysis (magnitude & axis of ast.)
Texte

45. Cataract Incisions Astigmatic Effects
Standard mm on axis CCI PKE
n: 172
Sup. Incision
Temp. Incision
SIA D D
Long D. et al. Ophthalmology 1996; 103:
Texte

46. Cataract Incisions Astigmatic Effects
Standard 3.2-mm on axis / temp. CCI PKE
n: 62
On Axis Incision
Temporal Incision
SIA
7 w PO
0.63 D
0.34 D *
Borasio E. et al. JCRS 2006; 32:
Texte

47. Cataract Incisions Astigmatic Effects
3-3.5-mm Incision & SIA Range Literature Summary
Incision Location
Superior
Oblique
On Axis
Temporal
SIA (D)
0.60 – 1.50
0.60 – 1.29
0.60 – 0.90
0.09 – 0.44 *
Texte

48. Cataract incisions 3.5-2.8-mm CCI Clinical Implications
Choice of Incision Location
Temporal Inc.
Nasal Inc.
Superior Inc.
1996
Kohnen T, Koch D.1
ATR D
WTR
2005
Tejedor J, Murube J.2
ATR < 0.75 D
ATR > 0.75 D
WTR >1.25 D
2009
Tejedor J, Perez J.3
Negligible Ast.
1 Kohnen T, Koch D. Curr Opin Ophthalmol. 1996; 7:75-80
2 Tejedor J, Murube J. Am J Ophthalmol. 2005; 139:
3 Tejedor J, Perez-Rodriguez J. IOVS. 2009; 50:
Texte

49. Comparison 3.0 / 2.2-mm Temporal CCI
SIA D
D *
Masket S. et al. JRS 2009; 25:
Texte

50. Comparison 1.8-mm C-MICS / 1.7-mm B-MICS
SIA D D
Wilczynski M. et al. JCRS 2009; 35:
Texte

51. STUDY Evaluate SIA Cataract Incisions
Nonrandomized prospective series 191 eyes
Group 1: 60 eyes PKE 3.2-mm sup. CCI
Group 2: 68 eyes PKE 2.2-mm sup. CCI
Group 3: 63 eyes PKE 1.8-mm sup. CCI
Two-plane incision with precalibrated metal knife
Unenlarged wound for IOL implantation
Group 1: SN60WF / Akreos AO IOLs
Group 2: SN60WF / Akreos MICS IOLs
Group 3: Akreos MICS IOL
Texte

52. Study Results Vector Analysis 3.2-mm 2.2-mm 1.8-mm Group
Arithmetic Mean
Vector Mean
3.2-mm D
0.77 at 10°
2.2-mm
O D
0.26 at 20°
1.8-mm
O D
0.16 at 13°

53. Cataract Incisions Texte Desirable to know astigmatic effect of CCI
SIA depends on incision size and location.
Significant less SIA with 1.8 / 2.2 / mm CCI.
SIA very limited with mm CCI.
Texte

54. Cataract Incisions Texte Desirable to know astigmatic effect of CCI
SIA depends on incision size and location.
Significant less SIA with 1.8 / 2.2 / mm CCI.
SIA very limited with mm CCI.
Clinical implications
To minimize SIA & optimize visual rehabilitation.
Customized incision size and location (>2.8-mm) based upon preop. astig.
Optimize UCVA with monofocal & premium IOLs.
Texte

55. Thank you for your attention
Fondation A. de Rothschild
Paris
Jean-Luc Febbraro MD
Texte