1. The authors of this poster have no financial interest in any products and technologies mentioned in this presentation.

2. Introduction  Key point of successful T-ICL implantation is exact lens axis alignment.  Starting point: estimation and marking of main meridian of the cornea (horizontal or vertical).  Second step: having main meridian as a reference, estimation and marking of the exact meridian of the lens alignment.

3. Classical 2 Steps Approach for Estimation and Marking of Corneal Meridians: First Step (Pre-Operative): Second Step (Intra-Operative):  Estimation and Marking of Horizontal Meridian:  «By Sight»  By Gravity Marker  By Horizontal Slit of Slit Lamp  marking of the exact meridian of the lens alignment (Mendoz Ring or Similar Instruments).

4. Advantages and Disadvantages of 2 Steps Classical Corneal Marking: Advantages: Disadvantages: 1) Time Consuming 2) Additional Intra- Operative Manipulations 3) Grating Period of Instruments – 10 Degree of Arc = Low Accuracy

5. Optimal Marking: 1. Pre-Operative 2. One Step 3. By Precision Protractor

6. Corneal Marking, NOT Conjunctival  Conjunctival Marker size is ≈ 5 Degree of Arc Corneal Spatula is More Precise

7. Methods:  Retrospective analysis of 2 Groups of Patients withHigh Myopic Astigmatism corrected by T-ICL implantation.  Both groups were matching in age, statue and degree of myopia: Patients were followed up 1 day, 1 week, 1, 3, and 6 months postoperatively. Purpose:  To evaluate the efficacy, safety and stability of High Myopic Astigmatism correction by Phakic Posterior Chamber Toric Intraocular Lens (T-ICL, STAAR, Switzerland).

8.  T-ICLs aligned by classical 2 Steps procedure +  clear corneal tunnel  T-ICLs aligned by direct preoperative marking of horizontal and exact axis of the lens orientation under SL with 360° ocular protractor +  limbal-corneal tunnel  Real T-ICL patient photo

9. Results: 6 months 100% patients was within ±1.00D, and 88%: +/-0.5D from intended refraction Group 1Group 2 Residual Cyl. 0.62 +/- 0.47D (0 – 1.25D) 0.38 +/- 0.24D (0.25 – 0.75D) Axis Misalignment of T-ICL 7.3±4.5° (0 to 15°) 3.2±2.1° (0 to 5°) Induced Corneal Astigmatism 0.56±0.21 D (0.25 to 0.75 D) 0.21±0.14 D (0.0 to 0.32 D)

10. Comments: Axis Misalignment of T-ICL 7.3±4.5° (0 to 15°) 3.2±2.1° (0 to 5°) Induced Corneal Astigmatism 0.56±0.21 D (0.25 to 0.75 D) 0.21±0.14 D (0.0 to 0.32 D) Group 1Group 2 Group 1Group 2  Twice Better Alignment of the Lenses in Group 2.  Twice Less Corneal Astigmatism Induced in Group 2 NO T-ICL Rotation in Any Group of PatientsNO T-ICL Rotation in Any Group of Patients

11. Conclusions: