Comparison Of Clinical Outcomes In Cataract Surgery At Near Physiologic Intraocular Pressure Using The Active Fluidics System Versus Higher Iop

This study aims to compare the need for additional topical anesthetic due to breakthrough discomfort during cataract surgery at a low intraocular pressure (IOP) of 30 mmHg using the Centurion active fluidics system with Active Sentry (AS) versus the traditional(higher) IOP (≈80mmHg at 110cm bottle height) using the Stellaris system.

Conducted at Shenzhen Eye Hospital, this prospective, randomized, comparative study enrolled 80 eyes scheduled for phacoemulsification surgery. Participants were randomly assigned to two groups: Group A underwent cataract surgery at near physiologic IOP (30mmHg) using Centurion with AS while the control group underwent cataract surgery at traditional IOP at 110cm bottle height (≈80mmHg) using Stellaris. 

Preoperative evaluation was performed, including ophthalmologic exams, IOP measurement, central corneal thickness (CCT), and corneal endothelial count. Breakthrough pain was managed with additional topical anesthetic and recorded. Patients rated their intraoperative pain on a visual analog scale (VAS), in which 0 was 'no pain' and 10 was 'unbearable pain’. Visual acuity, IOP, and CCT were recorded on the first day post-surgery and one week later.

The study found a significant difference in the primary outcome, with only 2.5% of patients (1 of 40 eyes) in Group A needing additional anesthetic compared to 12.5% (5 of 40 eyes) in Group B (p<0.05). Phacoemulsification times were similar, though Group A had a slight, non-significant reduction. Group A also reported lower mean VAS scores (1.17) than Group B (2.5) (p<0.01). Post-surgery, both groups showed no statistically significant differences in visual acuity and IOP. However, Group B experienced a greater increase in central corneal thickness (CCT) on the first day ((9.04% vs. 5.85%, respectively)(p<0.05)). After one week, both changes in CCT and corneal endothelial cell count were not significantly different between the groups.

Cataract surgery using the Centurion with Active Sentry at near physiologic IOP led to reduced need for additional anesthetic, lower visual analog scale (VAS) scores, and milder corneal edema compared to Stellaris system with traditional (higher) IOP settings. The Centurion system may provide a more comfortable experience and is worth considering as a preferred technique.