1. Fyodorov Eye Microsurgery Complex, Moscow, Russia Calibrated Vacuum Ring for Intrastromal Corneal Ring Segment Implantation in Different Types of Keratectasia K. Takchidi, B. Malyugin, S. Izmaylova, I. Latipov, S. Avramenko

2. Intracorneal ring segment Scientific Experimental Production Plant, Fyodorov Eye Microsurgery Complex, Russia Arc length – 160º Arc length – 160º Cross-section – hemisphere Cross-section – hemisphere Inner diameter – 5.0 mm Inner diameter – 5.0 mm Outer diameter – 5.6 mm Outer diameter – 5.6 mm Thickness range – 0.15 – 0.45 mm Thickness range – 0.15 – 0.45 mm Material - PMMA Material - PMMA

3. Classical Ferrara method Post-op “Leakage effect”

4. Our method of implantation Implantation of 1 segment Implantation of 1 segment 80% of corneal thickness 80% of corneal thickness Incision doesn’t depend on meridian (steep, flat) Incision doesn’t depend on meridian (steep, flat) ICRS should cover the most ectatic area ICRS should cover the most ectatic area Implantation of 1 segment Implantation of 1 segment 80% of corneal thickness 80% of corneal thickness Incision doesn’t depend on meridian (steep, flat) Incision doesn’t depend on meridian (steep, flat) ICRS should cover the most ectatic area ICRS should cover the most ectatic area

5. Total: 65 patients (68 eyes) 1 st group – II stage keratoconus (40 eyes) 2 nd group – III stage keratoconus (18 eyes) 3 rd group – pellucid marginal degeneration (4 eyes) 4 th group – post-Lasik keratectasia (6 eyes) mfage 1 st group 2812 27±7 2 nd group 117 29±8 3 rd group 31 29±2 4 th group 34 24±3

6. Calibrated Vacuum Ring (CVR)

7. UCVA and BCVA dynamic in 4 groups :

8. Pre-op 1 mon post-op 2 mon post-op OCT Visante

9. Pachymetry dynamic

10. pre-op post-op

11. Confocal microscopy pre-op post-op

12. Our results: Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory orthopedic and functional result Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory orthopedic and functional result Best functional results gained patients with II stage keratoconus and post-Lasik keratectasia Best functional results gained patients with II stage keratoconus and post-Lasik keratectasia Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory orthopedic and functional result Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory orthopedic and functional result Best functional results gained patients with II stage keratoconus and post-Lasik keratectasia Best functional results gained patients with II stage keratoconus and post-Lasik keratectasia

13. Our results : The use of new device – CVR helps to fix the eye properly, precisely mark corneal zones, ease tunnel formation and segment insertion that lead to reduction of surgery duration The use of new device – CVR helps to fix the eye properly, precisely mark corneal zones, ease tunnel formation and segment insertion that lead to reduction of surgery duration Final conclusion should be based on further observation Final conclusion should be based on further observation