Purpose: To evaluate the effect on contrast sensitivity function of laser in situ keratomileusis (LASIK) for the correction of myopia.
Setting: Alicante Institute of Ophthalmology, University of Alicante, Spain.
Methods: Fourteen eyes of 10 patients had LASIK to correct myopia ranging from 6.00 to 19.50 diopters (D). Mean preoperative myopia was 10.39 D +/- 3.69 (SD). Contrast sensitivity was tested preoperatively and 1, 3, and 6 months postoperatively using the CVS-1000E contrast sensitivity unit (VectorVision).
Results: Contrast sensitivity decreased 1 month postoperatively; the decrease was significant only at the low and intermediate spatial frequencies of 3 and 6 cycles per degree (cpd) (P = .034 and .030, respectively). Starting from the first month, there was rapid recovery of contrast sensitivity and at the third month, no statistically significant decrease at all spatial frequencies. Six months after surgery, there was an increase in contrast sensitivity values at 3, 12, and 18 cpd, although the changes were not significant.
Conclusion: Although LASIK decreased contrast sensitivity values at low and intermediate spatial frequencies for 1 month after surgery, these values rapidly returned to the preoperative values at 3 months. The improvement at certain frequencies at 6 months suggests that LASIK can improve the quality of vision in eyes with moderate and high myopia.