Gravity feed gets upgraded

The pressurized infusion system was designed to replace or augment gravity feed of infusion fluid during phacoemulsification and can be used with or without a change in usual bottle height. The concept for it derives from the use of external gas-forced infusion introduced by Amar Agarwal, MD, to maintain chamber stability when he was performing surgery through sub-1-mm incisions (Microphakonit).

The commercially available pressurized infusion system creates pressure using an internal compressor that can be added to any Stellaris system. It provides digital control of infusion pressure by infusing a preset level of air pressure into the balanced salt solution bottle.

"By allowing higher infusion rates, the system should also enable use of high vacuum, thereby perhaps reducing the use of ultrasound energy," he said. "So far, we can state with certainty that the system is easy to set up, with no learning curve, and that anecdotal observations about its performance are very positive."

Although there have been many advances to improve the efficiency and safety of phacoemulsification through improving control of ultrasonic energy and aspiration, Dr. Wallace said control of irrigation to optimize chamber stability has received little attention.

"Inflow of irrigation fluid still depends on gravity flow with equilibration of the system by controlling vacuum and aspiration on the back end," he said. "The pressurized infusion system takes a front-end approach to controlling irrigation directly."