Citation
Wang Yiyang, Yang Dong, Liu Liu, et al. Safety and efficacy of keratorefractive lenticule extraction using VISUMAX 800[J]. Chin J Exp Ophthalmol, 2026, 44(5):447-451. DOI: 10.3760/cma.j.cn115989-20260131-00058.
ABSTRACT [Download PDF] [Read Full Text]
Objective To evaluate the safety and efficacy of keratorefractive lenticule extraction (KLEx) performed using a 2 MHz femtosecond laser system.
Methods A prospective case series study was performed. Fifty-one patients (51 eyes) with myopia or myopic astigmatism who underwent KLEx surgery at the Eye & ENT Hospital of Fudan University between November 2024 and July 2025 were enrolled. Before the surgery and at 1 day, 1 week, and 6 months postoperatively, uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were assessed, and the corneal endothelial cell density (ECD), the coefficient of variation in cell area (CV), and the percentage of hexagonal cells (HEX) were measured using specular microscopy. Surgical safety, efficacy, predictability, accuracy, and stability were evaluated. This study adhered to the principles of the Declaration of Helsinki. The study protocol was approved by the Ethics Committee of Eye & ENT Hospital of Fudan University (No. 2024050-2). All participants were informed about the study purpose and provided written informed consent.
Results No serious intraoperative or postoperative complications were observed in any patient. At 6 months postoperatively, the safety index was 1.22±0.10, and the efficacy index was 1.16±0.14. The proportion of eyes achieving postoperative UDVA equal to or better than preoperative CDVA was 100% (51/51). A high correlation was observed between attempted and achieved refractive correction, with the regression equation of Y=0.961 8X-0.097 3 and the coefficient of determination (R 2) of 0.986. The proportion of eyes within ±0.50 D of the intended spherical equivalent was 100% (51/51). Compared with 1 month postoperatively, the spherical equivalent changed by only 0.08 D at 6 months postoperatively. There were significant overall differences in ECD and CV among different time points before and after surgery ( F=9.38, 4.75; both P<0.05). Compared with preoperative values, ECD was significantly lower at postoperative day 1, while CV was significantly higher at postoperative week 1 (both P<0.001). No significant difference in HEX was observed among different time points ( F=0.13, P=0.939).
Conclusions KLEx performed using a 2 MHz femtosecond laser system is safe and effective for the correction of myopia and myopic astigmatism.