Clinical outcomes and safety of preservative-free diclofenac sodium eye drops in SPT-assisted transepithelial photorefractive keratectomy

Background: Early postoperative pain and epithelial recovery remain important determinants of patient experience after surface ablation refractive surgery. Evidence comparing topical nonsteroidal anti-inflammatory drug (NSAID) options in Smart Pulse Technology (SPT)-assisted transepithelial photorefractive keratectomy (TransPRK) is limited. Methods: This retrospective cohort study included consecutive patients who underwent SPT-assisted TransPRK between January 2022 and December 2025. Patients received either standard postoperative care plus pranoprofen 0.1% eye drops (control group) or preservative-free diclofenac sodium 0.1% eye drops (PF diclofenac; observation group), administered four times daily for 3 days. Pain was assessed using the visual analog scale (VAS; 0-10) at 2, 24, 48, and 72 h. Secondary outcomes included time to complete epithelialization, time to bandage contact lens (BCL) removal, corneal haze grading, ocular surface and inflammatory signs, and adverse events. Results: A total of 239 patients were analyzed (control, n = 118; observation, n = 121). The observation group had significantly lower VAS pain scores at 2 h (5.40 ± 1.70 vs. 4.80 ± 1.60; P = 0.005), 24 h (4.20 ± 1.60 vs. 3.40 ± 1.50; P < 0.001), 48 h (2.80 ± 1.30 vs. 2.10 ± 1.20; P < 0.001), and 72 h (1.60 ± 1.00 vs. 1.20 ± 0.90; P = 0.001). A higher proportion of patients in the observation group achieved mild pain (VAS ≤ 3) at 24 h (53.7% vs. 38.1%; P = 0.016). Time to complete epithelialization (4.05 ± 0.88 vs. 4.32 ± 0.92 days; P = 0.021) and BCL removal (4.25 ± 0.90 vs. 4.56 ± 0.98 days; P = 0.012) were shorter in the observation group. Corneal haze and adverse events were comparable between groups, and no serious adverse events were observed. Conclusion: In SPT-assisted TransPRK, PF diclofenac was associated with improved early pain control and modestly faster epithelial recovery, without detectable differences in haze or short-term safety compared with pranoprofen.