USING OPD-SCAN III instrument method: Drag The joystick to focus on the screen prompt, and the device automatically starts to measure the aberration when the yellow focus is shown; Simk will change from black to rose red when the aberration is measured to start measuring the corneal topography, prompting the patient to blink the tear film evenly and press the button on the joystick when the focus is completed.The following data were obtained and analyzed: 4 mm high order STREHL rate (SR) , 4 mm high order corneal aberration (Hoa ) , Spherical Aberration (SA) , Coma Aberration (Coma) , Trefoil Aberration (RMS) , corneal aspheric index (Q, e) , corneal surface regularity index (SRI) , corneal surface asymmetry index (Sai)
The visual quality indexes of these patients before and after Orthokeratology treatment were compared: 4 mm higher strehl ratio (SR) , 4 mm higher order corneal aberrations (Hoa ) , Spherical Aberrations (SA) , Comas, Trefoil Aberrations (RMS) , corneal aspheric index (Q, e) , corneal surface regularity index (SRI) , corneal surface asymmetry index (Sai)