Current overview of Microkeratomes

Contact us for Microkeratomes, also advantages for Microkeratomes are Lower cost, Less inflammation, More efficient surgical flow.

1. Current overview of Microkeratomes Dr Kareeshma Wadia DNB, FNN Cataract, Cornea and Refractive Surgeon Director- Jehan Eye Clinic, Mumbai

2. NO FINANCIAL INTERESTS

3. PRINCIPLE High-precision oscillating-blade systems Docks to a suction ring Creates a lamellar corneal flap while the cornea is held under high pressure.

4. TYPICAL COMPONENTS OF A MODERN MICROKERATOME SYSTEM Console Motor Microkeratome head Applanator lenses Vacuum fixation Flap stop ring , which limits the microkeratome head through the fixation ring Foot switch

5. CONSOLE DSAEK Epi-K M2 One Use Plus

6. MOTOR AND MICROKERATOME HEAD Motor of keratome initiates Forward movement of head Oscillation of blade for the cut

7. MODALITIES OF MICROKERATOME PASS Rotative/ Pivoting flap creation : +: less space needed , +: hinge placement variable - : flap is thick – thin – thick due to the upward movement of the suction ring during the cut Hansatome , Carriazo

8. Linear flap creation : +: intraop visibility during flap creation , +: planar flap profile - : fixed hinge position Amadeus, SBK MODALITIES OF MICROKERATOME PASS

9. TYPE OF HEAD- Vertical / horizontal

10. SUCTION RING Suction ring will induce rise in IOP First step  choosing right size of suction ring Suction ring diameter determines How much of the cornea will protrude into the microkeratome primary determinant of flap diameter. Steep Cornea  more tissue will protrude Flat Cornea  less tissue will protrude

11. ALWAYS FOLLOW NOMOGRAM

12. VACUUM SETTING Achieving and maintaining adequate vacuum during microkeratome pass is critical to producing accurate flap. IOP at least 65mmHg for most microkeratomes Suction system and IOP should always be checked prior to every procedure Lower pressures can produce thinner cuts and irregular flaps Higher pressures can lead to chemosis , s/c hemorrhages , optic nerve injury

13. PLACING THE SUCTION RING The LASIK pneumatic suction ring is placed on the eye. With a suction pressure greater than 65 mm Hg, the instrument fixates the globe at the limbus and provides a dovetail track for the microkeratome.

14. THE NEED FOR TRANSIENT HIGH IOP IOP > 65 mm Hg Barraquer tonometer, a conical lens with a flat undersurface marked with a circle, and convex upper surface that acts as a magnifier. Dry cornea Gives uniform microkeratome section

15. MICROKERATOME – PRACTICAL TIPS Counsel well before taking the patient Briefly explain the procedure :- That it will take 5-7minutes per eye You will feel little pressure on eye For few seconds you won’t see the lights Not to squeeze the eyes Not to move the eyes You will hear some noises of Keratome and the laser machine

16. Blade assembly and inspection Check suction Always do a trial pass before actual procedure Listen to sound of blade oscillation MICROKERATOME – PRACTICAL TIPS

17. Always do marking on the cornea before keratome pass Advantages of marking : Proper alignment of the flap post ablation In case of free flap marking will help you to place the flap in it’s natural position Also helps in identifying the epithelium and stromal side of free flap MICROKERATOME – PRACTICAL TIPS

18. ADVANTAGES OF MECHANICAL MICROKERATOMES Proven history Lower cost More efficient surgical flow <30 secs Ability to create flaps in anterior stromal opacity/scar Less inflammation

19. Laser in situ keratomileusis was performed using the Moria microkeratome with the One Use-Plus SBK, M2 90 M2 110 head. The SBK head demonstrated the most accurate flap thickness, followed by the M2 90 head and the 110 head.

20. 1- No difference in visual acuity 2- Dry eye associated with MK and DLK with femto

21. Comparison between: Amadeus Carriazo Moria M2 SBK Nidek Hansatome CONCLUSIONS Variability between all 6 models Device labelling did NOT represent flap thickness achieved Thinner corneas had thinner flaps and similar for thicker corneas 1 st cut (1 st eye) had a thicker flap in B/L procedures

22. More flap predictability in Femto

23. Thank you Dr Kareeshma Wadia [email protected]