Active fluidics at lower intraocular pressure reduces intraoperative discomfort during phacoemulsification: a propensity score-matched cohort study.

BACKGROUND

Phacoemulsification under topical anesthesia requires adequate intraocular pressure (IOP) maintenance, but elevated IOP may contribute to patient discomfort and corneal stress. Active fluidics technology enables surgery at lower target pressures, yet the impact on patient-centered outcomes remains underexplored.

METHODS

This prospective cohort study compared the Centurion Vision System with active fluidics (target IOP 30 mmHg) vs. the Stellaris Elite System with gravity-based fluidics (approximately 62 mmHg) in patients undergoing phacoemulsification for age-related cataract. Propensity score matching (1:1) balanced baseline characteristics between groups. The primary outcome was intraoperative discomfort, assessed by supplemental anesthesia requirement and patient-reported pain scores (numerical rating scale, 0-10). Secondary outcomes included central corneal thickness (CCT), endothelial cell density (ECD), and visual acuity over 1 month of follow-up.

RESULTS

After matching, 130 patients (65 per group) were analyzed. Fewer patients in the Active Fluidics Group required supplemental anesthesia (3.1% vs. 13.8%; relative risk 0.22; 95% CI 0.05-0.98; p = 0.028). Median pain scores during phacoemulsification were lower in the Active Fluidics Group (1 vs. 3; p < 0.001). Day-1 CCT increase was smaller with active fluidics (28.4 vs. 46.8 μm; mean difference -18.4 μm; 95% CI -26.1 to -10.7; p < 0.001), though this difference resolved by 1 month. ECD loss and final visual acuity were comparable between groups. No intraoperative complications occurred.

CONCLUSION

Phacoemulsification using active fluidics at lower target IOP was associated with reduced intraoperative discomfort and attenuated early postoperative corneal edema while maintaining equivalent safety and visual outcomes.