Fyodorov Eye Microsurgery Complex, Moscow, Russia

Calibrated Vacuum Ring for Calibrated Vacuum Ring for Intrastromal Corneal Ring Segment Intrastromal Corneal Ring Segment Implantation in Different Types of Implantation in Different Types of

KeratectasiaKeratectasia

K. TakchidiK. Takchidi, , B. MalyuginB. Malyugin, , S. IzmaylovaS. Izmaylova, , I. LatipovI. Latipov, , S. AvramenkoS. Avramenko

Intracorneal ring segmentScientific Experimental Production Plant, Fyodorov Eye Microsurgery Complex, Russia

Arc lengthArc length – 1 – 16600ºº Cross-sectionCross-section – – hemispherehemisphere Inner diameterInner diameter – – 5.0 mm5.0 mm Outer diameterOuter diameter – 5 – 5..66 mm mm Thickness rangeThickness range – – 0.150.15 – –

0.45 mm0.45 mm MaterialMaterial - - PMMAPMMA

Classical Ferrara method

Post-opPost-op

““Leakage effect”Leakage effect”

Our method of implantation

Implantation of 1 segmentImplantation of 1 segment 80% of corneal thickness80% 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 areaICRS should cover the most ectatic area

Implantation of 1 segmentImplantation of 1 segment 80% of corneal thickness80% 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 areaICRS should cover the most ectatic area

Total: 65 patients (68 eyes)1st group – II stage keratoconus (40 eyes)2nd group – III stage keratoconus (18 eyes)3rd group – pellucid marginal degeneration (4 eyes)4th group – post-Lasik keratectasia (6 eyes)

mm ff ageage

11stst group group 2828 1212 2727±±77

22ndnd group group 1111 77 2929±±88

33rdrd group group 33 11 2929±±22

44thth group group 33 44 2424±±33

Calibrated Vacuum Ring (CVR)

UCVA and BCVA dynamic in 4 groups:

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

pre-op 1 mon post-op

6 mon post-op

1 year post-op

II stage KCIII stage KCPMDpost-LASIK

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

pre-op 1 mon post-op

6 mon post-op

1 year post-op

II stage KCIII stage KCPMDpost-LASIK

Pre-op 1 mon post-op

2 mon post-op

OCT Visante

Pachymetry dynamic

400

410

420

430

440

450

460

470

480

до операции 1 мес п/о 3 мес п/о 6 мес п/о

II stage KCIII stage KCPMDpost-LASIK

pre-op post-op

Confocal microscopy

pre-oppre-op post-oppost-op

Our resultsOur results::Our resultsOur results::

Single ICRS implantation into the area of Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory maximal corneal ectasia showed satisfactory orthopedic and functional resultorthopedic and functional result

Best functional results gained patients with II Best functional results gained patients with II stage keratoconus and post-Lasik keratectasiastage keratoconus and post-Lasik keratectasia

Single ICRS implantation into the area of Single ICRS implantation into the area of maximal corneal ectasia showed satisfactory maximal corneal ectasia showed satisfactory orthopedic and functional resultorthopedic and functional result

Best functional results gained patients with II Best functional results gained patients with II stage keratoconus and post-Lasik keratectasiastage keratoconus and post-Lasik keratectasia

Our resultsOur results::

The use of new device – CVR helps to fix The use of new device – CVR helps to fix the eye properly, precisely mark corneal the eye properly, precisely mark corneal zones, ease tunnel formation and segment zones, ease tunnel formation and segment insertion that lead to reduction of insertion that lead to reduction of surgery durationsurgery duration

Final conclusion should be based on Final conclusion should be based on further observationfurther observation