Comparing Post-Occlusion Surge at Decreasing Intraocular Pressures with Pressure Sensing Handpiece

Area of Science:

• Ophthalmology
• Surgical Technology

Background:

• Phacoemulsification is a common cataract surgery technique.
• Intraocular pressure (IOP) management is critical during cataract surgery.
• Post-occlusion surge can occur during phacoemulsification, potentially leading to complications.

Purpose of the Study:

• To compare post-occlusion surge pressure at various intraocular pressures (IOPs) using the Active Sentry handpiece.
• To evaluate the safety profile of the Active Sentry handpiece at different IOP settings.

Main Methods:

• An in vitro study using the Alcon Centurion platform and Active Sentry handpiece.
• Simulated phacoemulsification tip occlusion and release at IOPs of 30, 50, and 70 mmHg.
• Continuous monitoring of pressure changes using an electric pressure sensor.

Main Results:

• At 70 mmHg IOP, surge magnitude was 5.76 mmHg (duration 0.45s). At 50 mmHg IOP, surge magnitude was 5.76 mmHg (duration 0.52s).
• At 30 mmHg IOP, surge magnitude increased to 10.46 mmHg (duration 1.27s).
• Statistically significant differences in surge magnitude and duration were observed between 30 mmHg and both 50 and 70 mmHg IOPs (P < 0.05).

Conclusions:

• The Active Sentry handpiece does not increase surge risk when IOP is decreased from 70 to 50 mmHg.
• A decrease in operative IOP to 30 mmHg with the Active Sentry handpiece is associated with increased surge risk.
• The Active Sentry handpiece appears safe at 50 mmHg IOP regarding surge risk compared to 70 mmHg IOP.