Femtosecond Vs. Microkeratome-Assisted Lasik In Patients With Very Low Myopia: A Retrospective Analysis

The choice between femtosecond laser-assisted LASIK (FS-LASIK) and microkeratome-assisted LASIK (MK-LASIK) remains a subject of debate, particularly in patients with very low myopia, where visual outcomes and complication risks may differ subtly. FS-LASIK offers a more precise flap creation, potentially improving safety and reducing retreatment rates, while MK-LASIK remains widely used due to its cost-effectiveness and efficiency. This study aims to compare these techniques in a large cohort of very low myopia patients to determine whether FS-LASIK provides superior outcomes in terms of safety, efficacy, and complications.

A retrospective analysis of LASIK procedures performed at Care-Vision Laser Centers, a high-volume refractive surgery clinic in Tel Aviv, Israel, between January 2010 and June 2024.

A retrospective cohort study of 2098 eyes from patients aged 16–45 years with myopia up to -1.0 diopters who underwent FS-LASIK (n=817) or MK-LASIK (n=1281). Preoperative, intraoperative, and postoperative parameters – including visual acuity, refractive accuracy, safety, efficacy, and retreatment rates – were compared between the groups.

A total of 2,098 eyes were included (1,281 MK-LASIK, 817 FS-LASIK). Groups were similar in age (p = 0.34) and corneal thickness (p = 0.39). Preoperative keratometry showed minor differences, with FS-LASIK having steeper corneas (p = 0.036). Intraoperatively, FS-LASIK had a larger optical zone (p < 0.0001) and greater max ablation depth (p < 0.0001). Postoperatively, both groups achieved excellent UDVA (~1.00, p = 0.54), with FS-LASIK showing a trend toward lower residual astigmatism (p < 0.0001). Safety and efficacy indices were comparable (p = 0.19, p = 0.68). Retreatment rates were lower in FS-LASIK (0% vs. 0.39%). No cases of ectasia were reported.

Both FS-LASIK and MK-LASIK demonstrated excellent safety, efficacy, and refractive stability in patients with very low myopia. FS-LASIK demonstrated a significantly reduced postoperative astigmatism, suggesting a more precise and predictable outcome. While overall visual acuity was comparable, the trend toward improved refractive accuracy in FS-LASIK may offer advantages in long-term stability. FS-LASIK possibly provide lower retreatment rates, future study on larger cohort and with longer follow-up time is needed. These findings reinforce FS-LASIK as the preferred technique for very low myopia, particularly in patients prioritizing precision and possibly minimal retreatment risk.