Novel Phacoemulsification System Using Feedback-Based IOP Target Control
Narrative Responses:
Purpose
To evaluate the ability of Active Fluidics system utilizing active feedback fluidics to set and maintain target IOP in a laboratory simulated phacoemulsification model.
Methods
A transducer-based test fixture utilizing a simulated eye chamber was used to analyze simulated IOP stability with a phaco-emulsifier incorporating Active Fluidics, pressurized irrigation system with active feedback control, versus a gravity-based system without feedback control. The Active Fluidics system utilized a low stretch flexible polymer container for irrigation that was squeezed within a computer-controlled mechanism to generate pressure. The low compliance system allowed for very rapid changes in pressure and precise control. Optical-based non-invasive pressure sensors in the irrigation and aspiration paths provided feedback for IOP control algorithms.
Results
With the gravity-based system, irrigation path losses caused IOP to drop as a function of aspiration flow rate. The drop in IOP was approximately 20 mmHg at 30 cc/min and 45 mmHg at 60 cc/min. The Active Fluidics feedback system was able to maintain IOP to within approximately 5 mmHg throughout the range of 0 to 60cc/min.
Conclusion
The Active Fluidics System, which maintained better IOP control (5 mmHg at 0 to 60 cc/min), demonstrated improved stability during laboratory testing vs. the gravity-based system.