Feasibility of sleeveless bimanual phacoemulsification with the Millennium microsurgical system

Abstract

Purpose: To assess the feasibility of sleeveless bimanual phacoemulsification using the Millennium Microsurgical System (Bausch & Lomb Surgical) by measuring wound temperature during phacoemulsification. Setting: In vitro laboratory. Methods: The Millennium system was used in 6 eye-bank eyes using pulse mode and 80-milllisecond and 160-millisecond phaco burst mode width intervals. Wound temperatures were measured, and the wounds were observed for thermal injury. Results: In pulse mode and the nonoccluded state at 100% power, the maximum temperature was 43.8°C. In the occluded state at 30% power, the maximum temperature was 51.7°C after 70 seconds of occlusion. In phaco burst mode with a 160-millisecond burst-width interval, the maximum temperature was 41.4°C (nonoccluded at 100% power). At 80% power, the maximum temperature was 53.2°C within 60 seconds of full aspiration occlusion with the footpedal fully depressed. With an 80-millisecond burst-width interval in the nonoccluded and occluded states (100% power, footpedal fully depressed for 3 minutes), there was no significant temperature rise. The maximum temperature was 33.6°C in the nonoccluded state and 41.8°C in the occluded state. In all instances, the corneal wound remained clear. No wound burn or contracture was noted. Conclusions: The demonstrated temperature rises were under clinically unusual parameters. Phacoemulsification with a sleeveless needle through a small stab incision can be safely performed with the Millennium system using conventional phaco burst mode settings within certain parameters.