Pre existing astigmatism Surgically induced astigmatism

Transcription

1 Facing High Astigmatism Miltos Balidis PhD, FEBOphth

2 New demands new technologies Pre existing astigmatism Surgically induced astigmatism

3 Incidence of Astigmatism In a cataract population >1.0 D % >1.5 D 25-30% Leaming Study 2006 Hoffer KJ Biometry of 7500 eyes AJO.1980 SEP;90(3):360-8

4 Incidence of Astigmatism 4540 Eyes 13% <0.25D 64.6% D 22.2% > 1.50D Potential Toric IOL patients 41.2% Rayner 34.2% Alcon Teresa Ferrer Blasco et al J Cataract Refract Surg Jan;35(1):70-75

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6 Induced Astigmatism in CCI 3.5mm Temporal incision (0,74 0,71*) Nasal incision (1,65-1,41*) Barequet IS, et al Astigmatism outcomes of horizontal temporal versus nasal clear corneal incision cataract surgery. J Cataract Refract Surg Feb;30(2): Temporal incision(0.62 +/ ) Superior incision(1.44 +/ ) Simsek S,et al Effect of superior and temporal clear corneal incisions on astigmatism after sutureless phacoemulsification. J Cataract Refract Surg Apr;24(4):515-8 * 12 months follow up with vector analysis

7 Astigmatic correction Altering corneal curvature Opposite corneal cataract incisions Limbal relaxing incisions (LRI) Arcuate incision (Femto laser) Excimer Laser Corrections Laser Thermal keratoplasty Toric IOLs Anterior or Posterior chamber

8 TORIC LENSES Lenses with one Spherical and one Toric surface (Spherical Lens with a Cylinder superimposed upon it) These lenses form TWO line Foci at different distances and at right angles to each other

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10 Toricity

11 Toricity

12 Toric IOLs

13 Rayner T-flex Toric 573T and 623T Axis marks Applied to the anterior surface of the optic, diametrically opposed at 180º to each other. Indicate the IOL axis of the lowest power.

14 Rayner T-flex Toric Optic diameter 5.75 or 6.25mm. Superb anteroposterior, rotational and torsional stability with compressive haptics 12(12.5) - 9.5mm A-constant 118(SRK) Power range Sphere to Cyl to

15 Configuration The torus is always applied to the anterior surface. The Amon-Apple Enhanced Square Edge is applied just to the posterior surface. Therefore, unlike C-flex and Superflex which have no right or wrong way up in the eye, T- flex Toric IOLs must be correctly positioned with the anterior surface uppermost.

16 Implantation Mark axis on the limbus, with the patient on upright position, focusing at distance. Perform cataract surgery in the normal way, astigmatic neutral incision (or calculate your SIA in the IOL selection) Mark the axis of the highest power meridian Implant the IOL make sure that the lens is implanted the right way up in the eye Rotate the IOL until marked axis of the lowest power meridian on the IOL aligns with the axis of the highest power meridian of the cornea.

17 Rayner Centreflex IOL cyclotorsion 2-3 4eyes (24%) 5-7 4eyes (24%) Cylinder Mean Pre op 3.75 Δ Post op 0.95 Δ

18 Preop Planning 0-0,750,75 0,75-1,5 1, >3 LTK LRI OCI ΕXC TIOL

19 Correction of post keratoplasty astigmatism with toric TFlex IOL M. Balidis 1,2, Z.Zahariadis 2, G. Perganta 2,A. Vachtsevanos 2,G. Ioannidis 2 1. AHEPA Eye Clinic 2. Protypo Ophthalmiatrio,

20 On going retrospective analysis of 7 post-keratoplasty cataract patients (4 males, 3 female, mean age 53.5years ) using Toric high power IOL s Primary cause for transplantation was keratoconus ( 5 patients), desmetocele and trauma. IOL power calculation using corneal sagital topography (K1,K2) and ultrasonic biometry and laser interferometry (Biograph WAVELIGHT Alcon). Evaluated parameters were pre and postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), cylinder and keratometry, corneal and total Surgically Induced Astigmatic cylinder (SIAC).

21 Results Media n Sph Cyl Kmin Kmax Corneal SIAC Pre op Total SIAC Post op

22 Figure 1: Figure Scattergrams 3: Defocus of attempted equivalent vs. bar achieved graph refraction eyes 3 months postop < 0.50 D: 0 < 1.00 D 20% 100 Achieved % of Eyes (D) eyes 3 months postop OVERCORRECTED UNDERCORRECTED Attempted (D) Postoperative Defocus Equivalent Refraction (D)

23 Figure 5: Figure Change 4: in Uncorrected spectacle-corrected visual acuity visual bar acuity graphbar graph eyes 3 months 5 eyes postop 3 months postop 100 preop SCVA postop UCVA % of Eyes /12.5 [-3] 20/16 [-2] 20/20 [-1] 20/25 [0] [1] 20/30 [2] 20/40 [3] 20/50 [4] 20/60 [5] 20/80[6] 20/100 [7] 20/200 [8] 20/400 [9] [10] Cumulative Change in Snellen lines Visual of Acuity visual acuity

24 Interesting case Corneal biomechanics can be unpredictable especially in keratoconic patients Is there any place for capsular tension rings? J Alió, Journal of Cataract & Refractive Surgery, :34;9, CornealTopography Pre op Post op CORNEAL SIA 4.31!!!

25 Tips If toric marks not easily identified, IOL probably upside down. Consider repositioning in situ. Marks coincide with host - graft interface, eye tilting may help identification. Meticulous corneal wound closure especially in keratoconus Less topographic asymmetry, better visual performance

26 Conclusion First impressions of a study in progress Toric IOL effectively address post keratoplasty astigmatism IOL modifications of toricity marks can dramatically improve identification Visual acuity depends on corneal symmetry.

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28 Torica S καλύπτει όλες τις ανάγκες 3 pieces Z-loop ή C-loop Διάφανοι ή κίτρινοι 6 ή 7 mm διάμετρος οπτικού τμήματος Σταθεροποίηση στο σάκο ή στην αύλακα (sulcus)

29 Μέση απόκλιση ΕΟΦ από προεγχ. Άξονα Z-haptic 5,2 (0-15 ) 2.6º Μ.Ο. κυλ Προ εγχ 3.52 Δ +/ D Μετ εγχ1.23 +/ Δ 0.36 D De Silva DJ,et al Evaluation of a toric intraocular lens with a Z-haptic. J Cataract Refract Surg 2006; 32: μήνες μετεγχειρητικά Ποσοστό ενδοστροφής τουλάχιστον 10 με C-loop άκρα 32% Z 16% Μέγιστη στροφή 3 μήνες μετεγχ. με C-loop ακρα 21 Z 15,5 Warlo I, et al.rotational stability in intraocular lenses with C-loop haptics versus Z haptics in cataract surgery. Ophthalmologe 2005; 102 (10):