Q-optimized Algorithms: Theoretical Analysis of Factors Influencing Visual Quality After Myopic Corneal Refractive Surgery.
OBJECTIVE
To model the effect of pupil size, optical zone, and initial myopic level on the retinal image quality after Q-optimized myopic corneal refractive surgery.


METHODS
Different Q-optimized and paraxial Munnerlyn algorithms were tested using a schematic myopic eye model to analyze the optical quality of the final retinal image for initial myopic errors from -1.00 to -7.00 diopters (D). Different optical zones (5.5, 6, and 6.5 mm in diameter) and two pupil diameters (5 and 7 mm, mesopic-scotopic conditions) were included in the comparison. Modulation transfer function (MTF) and area under the MTF from 0 to 60 cycles per degree (MTFa) were calculated by ray tracing to evaluate this retinal image quality.


RESULTS
The Q-optimized algorithm with Q = -0.45 provided the highest MTF and MTFa results for myopic corrections less than -5.00 D. For refractive errors greater than -5.00 D, Q = -0.26 provided the highest MTF and MTFa results.


CONCLUSIONS
Q-optimized algorithms improve the visual outcomes with respect to the paraxial Munnerlyn algorithm for myopic corneal surgery. The results show that the Q value that optimizes the results of the Q-optimized algorithm depends on the degree of myopia to correct and the size of the pupil. [J Refract Surg. 2016;32(9):612-617.].
José R
JR
Jiménez
Aixa
A
Alarcón
Rosario G
RG
Anera
Luis
L
Jiménez Del Barco
D000465:Algorithms; D055253:Color Vision / Q000502:physiology*; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D055255:Mesopic Vision / Q000502:physiology*; D008962:Models, Theoretical; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D011680:Pupil / Q000502:physiology*; D054140:Refractive Surgical Procedures; D012160:Retina / Q000502:physiology