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Purpose: to analyze the results of a survey aimed at assessing the patients’satisfaction with the results of excimer laser or orthokeratological correction of myopia. Materials and methods. 135 patients aged 35 to 50 took part in a satisfaction survey: 105 after excimer laser and 30 after orthokeratological correction of myopia. Excimer laser surgery was performed with planned binocular hypocorrection within -0.75 — 1.5 D depending on age. To participate in the survey, the patients signed a preliminary consent. The questionnaire asked for age, gender, occupation, self-assessment of visual functions under a variety of conditions (vision at dusk, at close distance, at far distance, while driving a vehicle, etc.), self-assessment of satisfaction with the result. The questionnaire required to answer 15 questions on a multiplechoice basis. Results. Over 50 % of the patients have no difficulty working at close distance, at far distance, or when driving a vehicle, and do not restrict themselves in professional or everyday activities. More than 90 % of the patients would recommend excimer laser correction in binocular format with a planned hypo effect or orthokeratological correction to others. 125 out of 135 patients gave the maximum satisfaction score points. Conclusion: excimer laser correction of myopia with a planned hypoeffect in binocular format and orthokeratological correction can be recommended for patients over 35.

Purpose: a comparative study of corneal and total wavefront aberration changes after traditional PRK and FemtoLASIK.Material and methods. Corneal and total wavefront aberrations were studied on OPD-Scan III aberrometer (Nidek) in 63 patients (126 eyes) with moderate and high myopia before and after FemtoLASIK (Ziemer + Nidek-Quest, Japan) (44 patients, 88 eyes) and PRK (Nidek-Quest, Japan) (19 patients, 38 eyes). Spherical aberration (SA) was considered as the sum Z4 + Z8 + Z12.Results. The corneal asphericity coefficient Q changed to positive values after both types of intervention. Corneal RMS HOA increased in both Femto and PRK groups. Corneal Tilt 1 increased after FemtoLASIK and moved to negative values after PRK, corneal tilt 2 moved to negative values after Femto and to positive values after PRK. The vertical trefoil showed no significant change in the Femto group and dropped in the PRK group. The vertical and horizontal coma (coma 7, coma 8) changed synchronously. Corneal SA increased after Femtolasic, and became negative after PRK. The total aberrations showed a lesser change and the changes were not synchronized with the corneal ones: in particular, the RMS HOA fell from 0.28 ± 0.05 to 0.19 ± 0.05 in the Femto group, while the corneal RMS increased significantly. In the PRK group, the corneal RMS HOA showed some increase, but it was much less than corneal RMS: from 0.25 ± 0.07 to 0.62 ± 0.02 μm. The total SA increased from 0.11±0.03 to 0.27±0.02 in the Femto group and showed an insignificant drop from 0.09±0.03 to 0.03 ± 0.01, while remaining positive in the PRK group.Conclusions. The changes of the wavefront after FemtoLASIK and PRK are both significant and different. The revealed differences in the changes of corneal aberrations correspond to different profiles of the anterior surface of the cornea formed after FemtoLASIC and PRK. The internal optics of the eye partially compensates the corneal aberrations induced by excimer laser surgery.

Purpose: a covariance analysis of the planned and actually obtained refraction after excimer laser myopia correction surgery in middle-aged patients. Material and methods. 85 patients (170 eyes) aged 35 to 50 underwent excimer laser myopia correction surgery by FemtoLASIK. The patients were divided into 3 groups according to the degree of myopia: group 1 included 13 patients (26 eyes) with myopia from -1.25 to -3.0 D, group 2 had 42 patients (84 myopic eyes) from -3.25 to -6.0 D and group 3 had 30 patients (60 eyes) with myopia of -6.25 D or higher. Results. The patients with low myopia, independently of the age, revealed a postoperative refraction effect closer to that planned than the patients with moderate and high myopia. The difference (delta) between the planned and the obtained results was -0.35 ± 0.08 D (41%) in group 1, -0.58 ± 0.04 D (51.3%) in group 2 and -0.64 ± 0.05 D (46%) in group 3. The divergence between the respective indicators for figures for low and high myopic groups is statistically significant. Conclusion.Patients with low myopia over 35 years old can be recommended a symmetric hypocorrection in binocular format irrespective of the objective data regarding the initial corneal hydration, which affects the ablation volume. To achieve a better agreement between the planned and the actual hypoeffect (and, accordingly, a more precise dosage of the surgery) in patients with moderate and high myopia, it is important to introduce into clinical practice the technology of contactless measurement of corneal hydration.

Purpose. Comparative analysis of the wavefront aberrations and ophthalmoergonomic parameters after excimer laser and orthokeratological correction of myopia in patients aged over 35 years.Patients and methods. The study included 21 patients: 12 (24 eyes) after excimer laser correction of myopia (group 1) and 9 (18 eyes) after orthokeratology (group 2). The average age of patients after excimer laser surgery was 38.5 years, after orthokeratological correction 46.1 years. Special studies included ophthalmoergonomical tests: far and near distance visual acuity, capacity of the visual analyzer, visual productivity, reading velocity, mesopic vision, relative accommodation reserves, objective accommodative response, pseudo-accommodation volume. Wavefront aberrations were conducted on the OPD-scan 3.Results. The spherical equivalent of residual refraction was –0.625 ± 0.08D in the excimer group, and –1.58 ± 0.24D in orthokeratological group. Despite the difference in refraction, values of distance binocular and monocular visual acuity were the same in both groups: in group 1 monocular visual acuity was 0.74 ± 0.03, binocular 0.85 ± 0.03; in group 2 — 0.71 ± 0.06 and 0.89 ± 0.05 respectively. The parameters of both monocular and binocular accommodative response measured on Grand Seiko were 50 % higher in the excimer group compared to those in the orthokeratological group. Relative accommodation reserves appeared to be two times more in the excimer group. The volume of pseudo-accommodation was 2.375 ± 0.12D in group 1, which appeared to be 20 % more than in the group 2 (p = 0.0414). The level of wavefront aberrations was significantly higher in orthokeratological group with the exception of vertical aberrations and, especially horizontal coma, which were significantly higher after excimer laser surgery. Generally, the dynamics of aberrations in both groups correlates with changes of the corneal topography.Conclusion. Excimer laser surgery with hypocorrection is more recommended for patients aged 35–40, and orthokeratological correction for patients over 45 years old.