Clinical context

Visual acuity alone is insufficient when judging corneal disease or surgery. Topography and tomography, surface regularity, biomechanics, endothelial cell density, quality of vision and stability all matter. After refractive procedures, epithelial healing, dry eye, haze, ectasia and the need for enhancement should be assessed separately.

What was studied

Single-step TransPRK removes epithelium and performs stromal ablation within one laser sequence. StreamLight and SmartSurfACE use different platforms, but direct comparison is limited. This systematic review searched PubMed/MEDLINE, Embase, Cochrane Central and Web of Science from inception through 31 October 2025. Randomized trials, cohorts and case series in myopic eyes were eligible, with alcohol-assisted PRK serving as a common comparator. Forty-two studies were included and 15 entered the random-effects network meta-analysis.

How the evidence was produced

A meta-analysis combines several studies and can increase the precision of an overall estimate. Its conclusion still depends on the quality of the component studies, comparability of interventions and endpoints, statistical heterogeneity and publication bias. The pooled effect should be read with its confidence interval, sensitivity analyses and the reasons results differed across studies.

Key result No significant StreamLight–SmartSurfACE difference was detected for UDVA of at least 20/20: OR 0.75, 95% CI 0.13–4.22. For refraction within ±0.50 D, OR was 1.11, 95% CI 0.27–4.61. Postoperative spherical equivalent yielded SMD 0.02, 95% CI −0.31 to 0.35, and the safety index SMD was −0.28, 95% CI −1.89 to 1.34. Loss of at least two corrected-distance lines was rare. StreamLight was associated with faster epithelial healing, SMD −2.03, 95% CI −3.26 to −0.80, approximately 1–1.5 days earlier. Pain and haze were similar, and no statistically significant network inconsistency was detected.

How to interpret the result

Wide confidence intervals do not establish equivalence; they show that current evidence cannot confidently resolve a difference. The clearest finding, faster epithelial closure with StreamLight, came through a common comparator rather than a robust set of direct randomized comparisons. It should therefore remain provisional. Platform selection also depends on correction range, nomogram, optical zone, mitomycin use, postoperative protocol, surgeon experience and equipment access. Final refraction, optical quality, haze and safety matter alongside early healing speed.

Clinical applicability

The study may refine technique selection and informed discussion, but its conclusions depend on baseline corneal shape, stromal thickness, equipment, nomogram and surgeon experience. Applicability requires comparison of these factors and attention to variability, uncommon complications and follow-up duration rather than mean values alone.

Limitations

The network combined randomized studies, cohorts and case series, increasing bias and population heterogeneity. Indirect validity requires comparable populations, aaPRK comparators and protocols; absence of statistical inconsistency does not prove clinical homogeneity. Only 15 of 42 studies contributed to the quantitative network, and uncommon harms may be underdetected. Verify the search, protocol registration, risk-of-bias assessment, direct-comparison count, network geometry, heterogeneity, healing and haze definitions, outcome timing, sensitivity analyses, publication bias, funding and conflicts.

What to verify in the source

Use the DOI below to verify complete methods, result tables, funding and conflicts of interest.