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@#AIM:To evaluate the effect of higher-order aberrations(HOAs)after topography-guided and wavefront-optimized femtosecond laser-assisted <i>in situ</i> keratomileusis(FS-LASIK). <p>METHODS: We searched on PubMed, the Cochrane Library, Medline, CNKI, CBM, VIP and WanFang Data database for randomized controlled trials(RCTs)and comparative studies(CTs). The published languages were limited to Chinese and English. The risk bias tool provided by the Cochrane cooperation scale and Newcastle-Ottawa Scale were used to assess the risk bias of included studies of RCTs and CTs. The published biases of included studies were assessed by the Egger test. Meta-analysis was performed with Review Manager 5.4.<p>RESULTS: Two randomized controlled trials and six comparative studies with a total of 987 subjects were included(482 in the topography-guided FS-LASIK group, 505 in the wavefront optimized FS-LASIK group). The Meta-analysis showed that the topography-guided group has a better effect than the wavefront-optimized group in spherical equivalent, the difference between the two groups was statistically significant \〖<i>WMD</i>=0.11, 95%<i>CI </i>(0.07, 0.14), <i>P</i><0.00001\〗. And the results also indicated that there was a significant difference between the two groups with HOAs \〖<i>WMD= </i>-0.09, 95%<i>CI </i>(-0.13,-0.05), <i>P</i><0.0001\〗, spherical aberrations \〖<i>WMD=</i>-0.05, 95%<i>CI </i>(-0.09, -0.01), <i>P</i>=0.008\〗 and coma \〖<i>WMD=</i>-0.08, 95%<i>CI </i>(-0.12, -0.05), <i>P</i><0.00001\〗.<p>CONCLUSION: Based on the available evidence, topography-guided FS-LASIK has higher diopter and lower HOAs, spherical aberrations and coma than wavefront-optimized FS-LASIK.
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Purpose: To compare the visual outcomes and higher order aberrations (HOAs) following wavefront optimized (WFO) laser in situ keratomileusis (LASIK) versus topography-guided customized ablation (TCAT) LASIK for myopia and myopic astigmatism. Methods: Patients who underwent femtosecond-assisted LASIK for myopic correction between August 2016 and October 2017 were included in this interventional prospective case series. The following parameters were evaluated preoperatively and at 3 months' postoperative visit: uncorrected distance vision acuity (UDVA) and corrected distance vision acuity (CDVA), manifest refraction, and HOAs. Results: Two hundred eyes of 100 patients were included in the study. At 3 months' postoperative visit, 92% and 90% eyes in the TCAT and WFO groups, respectively, demonstrated a UDVA of 20/20 or better (P = 0.90). A residual manifest spherical equivalent within 0.5 D was achieved in 100% and 95% of the eyes in the TCAT and WFO groups, respectively (P = 0.10). No significant difference was observed in the HOAs induced in both the groups, with slightly lower induction of trefoil and horizontal coma in the TCAT group. Conclusion: Both groups demonstrated similar refractive efficacy and predictability, with greater gain of CDVA following TCAT ablation. HOAs induced were not significantly different between the two groups. Further studies are needed to validate the superiority of one procedure over the other.
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PURPOSE: To compare higher-order aberrations (HOAs) and visual acuity after wavefront-guided and wavefront-optimized laser keratorefractive surgery. METHODS: This retrospective study consisted of consecutive cases of eyes that underwent wavefront-guided (VISX S4 CustomVue(R)) or wavefront-optimized (WaveLight(R) EX500) laser assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK). Preoperative and postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction spherical equivalent (MRSE), and preoperative and 3 month postoperative HOAs were compared. RESULTS: There were no statistical differences in UCVA, BCVA, MRSE, or total HOAs in either the LASIK and PRK groups (all p > 0.05). Induced amount of spherical aberration (SA) was significantly lower in the wavefront-optimized LASIK and PRK than wavefront-guided LASIK and PRK. CONCLUSIONS: In laser keratorefractive surgery, wavefront-guided and wavefront-optimized platforms produced equivalent visual outcomes and no differences in total HOAs. However, the wavefront-optimized platform caused less spherical aberration 3 months after operation.
Subject(s)
Keratomileusis, Laser In Situ , Photorefractive Keratectomy , Retrospective Studies , Visual AcuityABSTRACT
Purpose: To study the change in ocular aberrations after wavefront optimized (WFO) laser in situ keratomileusis (LASIK) for correction of myopia and to analyze causative factors that may influence them. Materials and Methods: This was a prospective case series. WFO LASIK was performed for the correction of myopia, using the hansatome (Bausch and Lomb) microkeratome to create the flap and the Allegretto laser (Wavelight Technologie) to perform the ablation. The Allegretto wave analyser (Tscherning-type) measured the ocular aberrations prior to LASIK , one month and six months postoperatively. Results: The mean age of the 59 patients included in the study was 25±5.64 years and the mean spherical equivalent of the 117 eyes that underwent LASIK was ‒5.33±1.22 preoperatively and ‒0.21±0.38 postoperatively. Hundred and two eyes of 117 (87%) achieved uncorrected visual acuity (UCVA) of 20/20 or better after WFO LASIK and 104 of 117 eyes (89%) were within ±0.5D of the attempted refractive correction. There was a 1.96-fold increase in total root-mean-square of higher order aberrations. Induced changes in seven of the 22 higher order Zernike terms showed a significant linear correlation with the refractive correction attempted. Larger ablation zones induced less spherical aberration. Conclusion: In spite of an excellent visual outcome, WFO LASIK induces significant higher order aberrations. Large ablation zones reduce the induction of spherical aberration.