The Pressure-Controlled Infusion System: a new instrument for closed-system surgery

We present the new Pressure-Controlled Infusion System (PCIS), designed to automatically regulate intraocular pressure (IOP) during surgery. Studies were performed with rabbits in which we compared the true IOP during closed-system surgery using gravity-fed infusion with the automatic control provided by the PCIS. The results from irrigation/aspiration of the lens cortex, wound closure, and vitrectomy show that the PCIS performs two functions during closed surgery: it automatically maintains the baseline IOP at the pre-set level, and it dramatically decreases the pressure fluctuations that occur with gravity infusion.