Improving Safety Of Phacoemulsification Cataract Surgery In High-Risk Patients Using Real-Time Anterior Chamber Pressure Sensing And Regulation

Microincision phacoemulsification surgery (MICS) is the standard of care for the treatment of cataract. Anterior chamber instability and/or posterior capsule protrusion remain the most important risk factors for complications like posterior capsular rupture and postoperative cystoid macular edema. An innovative phacoemulsification handpiece is available with a built-in fluidics pressure sensor detects pressure in real time to stabilize the anterior chamber during MICS. This study aims to compare anterior chamber flare (ACF) central corneal thickness (CCT) as indicators of surgical trauma between the Centurion vision system with active sentry (Centurion-AS; Alcon, Freiburg, CH) and the Eva phacoemulsification system (DORC BV, Zuidland, NL).

The Department of Ophthalmology of the Medical University of Innsbruck is an ophthalmological tertiary referral center serving a population of approximately 750.000 in Tyrol, Austria.

Prospective, randomized, controlled, observational study involving 120 patients with advanced or mature cataract scheduled for MICS. Patients are operated by three experienced phacoemulsification surgeons using an identical technique, and are randomly included in one of two study arms using the DORC Eva phacoemulsifier or the Centurion-AS at comparable fluidics settings. All patients receive the same postoperative treatment. Intraoperative parameters, pre-versus postoperative ACF, CCT, and macular thickness are assessed pre- and postoperatively on day 1 and 7.

Patient recruitment for this study is ongoing. The primary endpoint is the difference of pre-versus postoperative ACF on day 1 and 7 between Centurion-AS and routine MICS. The secondary endpoints include CCT, central macular thickness (OCT derived), 5mm corneal volume (Pentacam derived), endothelial cell density and best spectacle corrected visual acuity. Additionally, phacoemulsification duration and energy, fluid volume measurements, pupil dynamics and the occurrence of intra- or postoperative complications including posterior capsular ruptures, vitreous loss and postoperative cystoid macular edema are recorded.

Intraoperative fluidics and pressure sensing stabilizes the anterior chamber and may be associated with decreased postoperative ACF or measures of surgical trauma, thus increasing the safety and feasibility of MICS in advanced or mature cataracts.