Evidence map›Paper›PMID 40947529›Full record

SynthesisJournal of cataract and refractive surgery2026

Photorefractive keratectomy in patients with thin corneas: systematic review and meta-analysis of clinical outcomes and complications.

Farbod Semnani, Amirmasoud Rayati Damavandi, Mirsaeed Abdollahi, Mohamad Sajadi, Mohammad-Mehdi Sadoughi, Kiana Hassanpour

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in Journal of cataract and refractive surgery, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Farbod SemnaniFrom the National Center for Health Insurance Research, Tehran, Iran (Semnani); School of Medicine, Tehran University of Medicine (TUMS), Tehran, Iran (Semnani, Rayati Damavandi, Sajadi); Nikookari Eye Hospital, Tabriz University of Medical Sciences, Tabriz, Iran (Abdollahi); Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran (Sadoughi, Hassanpour).ORCID 0000-0002-8964-419
Amirmasoud Rayati Damavandi
Mirsaeed AbdollahiORCID 0000-0002-2444-1172
Mohammad-Mehdi Sadoughi

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

topicTo systematically investigate the safety and efficacy of photorefractive keratectomy (PRK) or transepithelial PRK (transPRK) in patients with thin corneas. CLINICAL RELEVANCE: Concerns exist regarding the outcomes of refractive surgeries including PRK/transPRK in patients with thin corneas.

methodsThis study was registered prospectively in PROSPERO with an ID of CRD42023457156. It was conducted according to the Cochrane Handbook for Systematic Reviews of Interventions and reported in line with the PRISMA 2020 Consensus Statement. We searched 7 databases and 3 registries from January 1, 1985, until November 30, 2024: PubMed, Web of Science, Scopus, Google Scholar, Embase, ProQuest, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov , and International Clinical Trials Registry Platform. Our primary outcomes include the safety index (SI), efficacy index (EI), and corrected distance visual acuity (CDVA) changes, while our secondary outcomes include predictability and the rate of complications (including corneal ectasia and haze). We included any observational or interventional study reporting data on the primary or secondary outcomes of PRK or transPRK in patients with a mean central corneal thickness <500 μm, with no history of previous ocular pathology or surgery. The outcome estimates and 95% CIs were derived from a random-effects model meta-analysis to account for possible heterogeneity.

results946 eyes from 10 studies were included. All included studies were case series, either retrospective (n = 4) or prospective (n = 6). 4 studies (n = 4) reported the SI and EI, with pooled estimates of 1.01 (95% CI 0.73-1.29) and 1.01 (95% CI 0.98-1.04) after sensitivity analysis, respectively. The mean postoperative change in CDVA was -0.01 (95% CI -0.07 to 0.05). Compared with baseline values, a mild yet non-significant improvement in CDVA was observed (standardized mean difference -0.20 95% CI -0.89 to 0.49). The pooled predictability within ±0.5 diopter of emmetropia, based on data from 6 studies, was 0.83 (95% CI: 0.98 to 1.04). No study reported any cases of corneal ectasia after surgery.

conclusionsPRK/transPRK seems to be a safe and effective refractive surgery for thin corneas with simple or astigmatic myopia and without any other ocular pathologies/topographic abnormalities. However, the power analysis and insufficient follow-up call for future studies to draw definitive conclusions about safety and efficacy.

Indexed as

CorneaLasers, ExcimerMyopiaPhotorefractive KeratectomyPostoperative ComplicationsHumansRefraction, OcularTreatment OutcomeVisual Acuity

Identifiers

PMID40947529
PMCPMC12777601

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.