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Contact us for Microkeratomes, also advantages for Microkeratomes are Lower cost, Less inflammation, More efficient surgical flow <30 secs u200band visit our website for more information.
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Current overview of Microkeratomes Dr Kareeshma Wadia DNB, FNN Cataract, Cornea and Refractive Surgeon Director- Jehan Eye Clinic, Mumbai
PRINCIPLE High-precision oscillating-blade systems Docks to a suction ring Creates a lamellar corneal flap while the cornea is held under high pressure.
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
CONSOLE DSAEK Epi-K M2 One Use Plus
MOTOR AND MICROKERATOME HEAD • Motor of keratome initiates • Forward movement of head • Oscillation of blade for the cut
MODALITIES OF MICROKERATOME PASS • Rotative/Pivotingflapcreation: • +: lessspaceneeded, • +: hinge placement variable • - : flapisthick – thin – thick • due to the upwardmovement • of the suction ring during the cut • Hansatome, Carriazo
MODALITIES OF MICROKERATOME PASS • Linearflapcreation: • +: intraopvisibilityduringflapcreation, • +: planarflap profile • - : fixedhinge position • Amadeus, SBK
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
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 tochemosis, s/c hemorrhages, optic nerve injury
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.
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
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
MICROKERATOME – PRACTICAL TIPS • Blade assembly and inspection • Check suction • Always do a trial pass before actual procedure • Listen to sound of blade oscillation
MICROKERATOME – PRACTICAL TIPS • 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
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
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.
1- No difference in visual acuity 2- Dry eye associated with MK and DLK with femto
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 1st cut (1st eye) had a thicker flap in B/L procedures
Thank you Dr Kareeshma Wadia jehaneyeclinic@gmail.com