Cohort Study: Corneal Higher-Order Aberrations and Its Related Factors in Chinese People with Emmetropia

Abstract Background There are few reports regarding the influence of varying illumination on the compensation effect before and after corneal refractive surgery. We aimed to evaluate the changes in refraction, higher-order aberrations, and aberration compensation between mesopic and photopic illumination before and after small incision lenticule extraction. Methods In this prospective cohort study, only the right eyes of patients who underwent small incision lenticule extraction for the correction of myopia and myopic astigmatism at the Tianjin Eye Hospital were included. Wavefront refraction and higher-order aberrations were measured preoperatively and 3 months postoperatively under mesopic and photopic illumination. Compensation factors were calculated as 1 − (aberration of the whole eye/aberration of the anterior corneal surface). Results Forty patients undergoing small incision lenticule extraction were enrolled. All surgeries were completed without postoperative complications. Preoperatively, the eyes only had a statistically significantly higher (t = − 4.589, p < .001) spherical refractive error under mesopic vs. photopic illumination (median [interquartile range], − 6.146 [2.356] vs. − 6.030 [2.619] diopters [D]), whereas postoperatively, the eyes also exhibited statistically significantly higher (t = − 3.013, p = .005) astigmatism (− 0.608 [0.414] vs. − 0.382 [0.319] D). Differences in spherical refraction between the two illuminations were the highest in postoperative eyes (Δ > 0.5 D). Only postoperative eyes exhibited statistically significant elevations (t ≥ 4.081, p < .001) in higher-order aberrations under mesopic illumination, and only preoperative eyes exhibited statistically significantly enhanced (χ2 = 6.373, p = .01 for fourth-order and χ2 = 11.850, p = .001 for primary spherical aberrations) and decreased (χ2 = 13.653, p = .001 for horizontal trefoil) compensation factors under mesopic illumination. Conclusions Exaggerations in higher-order aberrations and myopic shift after small incision lenticule extraction became apparent under mesopic illumination. Slight undercorrection may have an enhanced effect under low illumination and may reduce night vision. The specific changes in compensation effects in preoperative eyes may improve optical quality under mesopic illumination. Postoperative eyes have reduced compensation ability, specifically for spherical aberrations, under mesopic illumination, which may diminish night vision. Further studies that include the measurement of subjective night vision parameters should be conducted.

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Faculty Opinions recommendation of Higher Order Aberrations in Femtosecond Laser-Assisted Versus Manual Cataract Surgery: A Retrospective Cohort Study.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.735074375.793558140 ◽

2019 ◽

Author(s):

George O Waring IV ◽

Larissa Gouvea

Keyword(s):

Cohort Study ◽

Femtosecond Laser ◽

Cataract Surgery ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Higher Order ◽

Higher Order Aberrations

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Ocular higher-order aberrations in patients with various refractive errors

Sohag Medical Journal ◽

10.21608/smj.2017.37055 ◽

2017 ◽

Vol 21 (3) ◽

pp. 177-183

Author(s):

Eman Morad ◽

Mohamed Abd_ Elateef ◽

Mohammad Mousa ◽

Ismael Abdelatif

Keyword(s):

Higher Order ◽

Refractive Errors ◽

Higher Order Aberrations

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Matched comparison of corneal higher order aberrations induced by SMILE to femtosecond assisted LASIK and to PRK in correcting moderate and high myopia: 3.00mm vs. 6.00mm

BMC Ophthalmology ◽

10.1186/s12886-021-01987-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mohammad Miraftab ◽

Hassan Hashemi ◽

Mohammadreza Aghamirsalim ◽

Shiva Fayyaz ◽

Soheila Asgari

Keyword(s):

Visual Acuity ◽

High Myopia ◽

Spherical Aberration ◽

Corneal Thickness ◽

Higher Order ◽

Laser In Situ Keratomileusis ◽

Higher Order Aberrations ◽

Surgical Methods ◽

Matched Comparison ◽

Surgical Group

Abstract Background The refractive surgeries induce corneal higher order aberrations (C-HOAs). In this study, change of C-HOAs after small-incision lenticule extraction (SMILE) compared to femtosecond assisted laser in situ keratomileusis (femto-LASIK), and to photorefractive keratectomy with mitomycin-C (PRK) under photopic and mesopic conditions. Methods In this prospective study, age, gender, and apical corneal thickness (ACT) matched cases with moderate myopia [spherical equivalent (SE) 3.00 to 6.00D) to high myopia (SE > 6.00D)] were enrolled. In addition to visual acuity and refraction, total C-HOA, coma, spherical aberration (SA), and trefoil in the 3- and 6-mm zones were measured before and 3 and 6 months after surgery. Results Overall, 372 moderate myopia cases (124 eyes of 124 individuals in each surgical group) and 171 high myopia cases (57 eyes of 57 individuals in each surgical group) were enrolled. At baseline, the differences in age, gender, ACT, uncorrected and corrected visual acuity, and SE were not statistically significant between subgroups of surgical methods within each myopia group (all P > 0.05). At 12 months, in the moderate myopia group, there was less increase in 6-mm zone total C-HOA, coma, and SA with SMILE compared to the other groups (all P < 0.05). In the high myopia group, there was greater increase in photopic total C-HOA and trefoil and less increase in mesopic SA with SMILE (all P < 0.05). Conclusions In correction of moderate myopia, SMILE has better results in mesopic condition. In high myopia correction, femto-LASIK and PRK have better results in photopic and SMILE in mesopic condition.

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