Evaluation of intraocular pressure fluctuations with differing phacoemulsification approaches.

Simultaneous two-camera video tracings of phacoemulsification surgery and intraocular pressure fluctuations were made. The fluctuations were transmitted to a quartz pressure transducer through a chamber maintainer that was plugged into the anterior chamber. The transducer was connected to a monitor and recorder calibrated to measure pressure variations between -8.6 and +60 mm Hg. Using common audio for synchronization, the pressure tracings were keyed over the surgical videos and combined in a single film. High, medium, and low inflow volume techniques used by many surgeons exhibiting commensurately higher or lower intraocular pressure fluctuations were scrutinized. Methods to increase inflow volume without a proportionate pressure increase were devised.