The Three Phases of SMILE
Phase 1: Initial docking with precise centration. During this phase, proper head position is achieved by tilting the patient's head medially to avoid nasal contact with the cone of the contact glass interface. Precise centration should be verified before the initiation of suction.
Phase 2: Femtosecond laser delivery. Femtosecond laser pulses are fired in a spiral pattern with a pulse energy of 120 to 170 nJ and a repetition rate of 500 kHz.
Phase 3: Tissue dissection and lenticule removal. The tissue disruption planes created by the laser include the posterior lenticule surface, vertical edge cut, anterior lenticule surface, and corneal sidecut (Figures 1 and 2).
SMILE OVER LASIK
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Mahipal Sachdev, MD
• Chairman, Medical Director, and Senior Consultant Ophthalmologist, Centre For Sight, New Delhi, India
• Financial disclosure: Travel grant (Carl Zeiss Meditec)