Comparison of Q-value-guided laser-assisted in situ keratomileusis and standard laser in situ keratomileusis for myopia

Abstract

Background: Previous studies examining the safety and efficacy of Q -value-guided laser-assisted in situ keratomileusis (LASIK) for treating myopia have yielded inconsistent results. We, therefore, performed a meta-analysis to clarify this issue Methods: Various databases were conducted up to November 21, 2018. All randomized controlled trials and cohorts that compared Q -value-guided LASIK with standard LASIK were selected. Mean differences (MDs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the strength of the correlations. Additionally, different subgroup analyses and publication bias tests were performed. Data were extracted including the number of postoperative uncorrected visual acuity (UCVA) of 20/20 or better, postoperative UCVA, preoperative and postoperative Q -value, postoperative refractive spherical equivalent (SE), the number of postoperative SE within ±0.5D, higher order aberration (HOA), coma-like aberration and spherical-like aberration. Results: A total of seventeen studies with 2640 patients and 3,358 eyes were included. It has been shown that postoperative Q -value (MD = -0.42; 95% CI: -0.64, -0.21; P < .001), HOA (MD = -0.14; 95% CI: -0.23, -0.06; P = .001), spherical-like aberration (MD = -0.19; 95% CI: -0.32, -0.06; P = .004) rather than postoperative UCVA (MD = 0.04; 95% CI: 0.01, 0.07; P = .012) were significantly better in the Q -value-guided LASIK than standard LASIK. However, the pooled results revealed that no significant differences were found between the 2 paired groups of postoperative UCVA of 20/20 or better (OR = 1.09; 95% CI: 0.62, 1.92; P = .763), preoperative Q -value (MD = -0.00; 95% CI: -0.02, 0.02; P = .922), postoperative refractive SE (MD = 0.08; 95% CI: -0.09, 0.25; P = .336), coma-like aberration (horizontal: MD = -0.00; 95% CI: -0.03, 0.03; P = .966; vertical: MD = -0.01; 95% CI: -0.03, 0.01; P = .263) and postoperative SE within ±0.5 D (OR = 1.06; 95% CI: 0.48, 2.33; P = .886). Likewise, similar results were detected in some corresponding subgroups. Conclusion: Q -value-guided LASIK is a safe, effective and predictable surgical option for treating myopia, especially showing superiority over standard LASIK in postoperative Q -value, HOA and spherical-like aberration. However, more detailed studies are required to confirm our conclusions in advanced researches.

Femtosecond laser-assisted in situ keratomileusis with topography-guided or asphericity-adjusted derived data: a comparative contralateral eye study

“…Second, we did not analyse the pre and pos Q value and the main reason was that Galilei calculates asphericity through the term eccentricity (ε 2 ) [ 29 ], which is different from the Q measured by Topolyzer and we thought it could cause misunderstanding. In our favor we can cite the systematic review by Zhang et al [ 30 ] which reports no significant difference in preoperative Q-value in 11 similar studies between 2 paired groups. Third, the sample size was not sufficiently large to show the real advantages of one group over another.…”

Laser‐based refractive surgery techniques to treat myopia in adults. An overview of systematic reviews and meta‐analyses

“…In addition, seven potentially eligible titles were retrieved by using the RSS feeds appliances among the databases up until 10 April 2021. A total of six of these publications met the inclusion criteria (Chang et al 2021, Fu et al 2021, Hamam et al 2020, Li et al 2020, Zhang et al 2020a, Zhang et al 2020b. Finally, 36 systematic reviews were included in the qualitative synthesis (Fig.…”

“…The comparisons were listed according to the order in which each type of surgery was developed: PRK was the first refractive surgery developed (1996), followed by LASIK and LASEK (1998). Soon after, laser femtosecond was introduced on the market The GRADE SoF tables were not implemented in three systematic reviews; the grading of evidence was thus conducted by two authors (SPO and RSP) (Chen et al 2012, Wang et al 2017, Zhang et al 2020b. A metaevidence summary and grading of the 41 outcomes reported in the systematic reviews are provided in Table 2.…”

“…6). Moreover, 9 of the 36 included reviews evaluated certainty of evidence using the GRADE approach; 4 of them were non-Cochrane reviews (Chen et al 2012, Shen et al 2016, Wang et al 2017, Zhang et al 2020b.…”

“…The nine least biased reviews (those with moderate quality) comprised 102 indexed titles. Five reviews used the Cochrane collaboration tool to calculate the risk of bias (RoB) (Kahuam-L opez et al 2020, (Shen et al 2016) and one used the NOS for cohort studies (Zhang et al 2020b). One study used the Jadad scale to assess both randomized and nonrandomized studies, but it provided only the summary scorenot the full assessment of each item (Wang et al 2017).…”