Purpose: To evaluate flow rates and duty cycle for different sizes of ultra-high-speed pneumatic vitreous cutters.
Methods: A precision balance measured the mass of water and vitreous removed from a vial. Porcine vitreous was obtained within 12 hours of killed at a local slaughterhouse and kept at 4 °C. Twenty-, 23- and 25-gauge (n = 3 of each gauge) pneumatic cutters were tested at 0 (water), 1,000, 2,000, 3,000, 4,000, and 5,000 cuts per minute with aspiration levels of 100, 200, 300, 400, 500, and 600 mmHg. Frame-by-frame analysis of high-speed video was used to determine the duty cycle.
Results: Larger gauge cutters associated with higher aspiration levels produced greater vitreous and water flow rates (P < 0.05). As the cut rate increased, the vitreous flow rate increased (maximum flow at 5,000 cuts per minute) and the water flow rate decreased (P < 0.05). The duty cycle of the new-generation cutters decreased as cut speeds increased, using all 3 gauges (P < 0.001). Vitreous flow rates averaged 10 times less than water flow rates using the same cutter at the same settings.
Conclusion: Ultra-high-speed vitreous cutters produce consistent vitreous and water flow rates across the tested range of cuts per minute and aspiration levels.