Experimental study comparing 2 different phacoemulsification systems with intraocular pressure control during steady-state flow and occlusion break surge events.

PURPOSE: To compare peak surge and surge duration time after occlusion break, incision leakage compensation, and passive vacuum for 2 phacoemulsification systems. SETTING: Carl Zeiss Meditec AG, Oberkochen, Germany. DESIGN: Laboratory study. METHODS: A spring-eye model was used to test Alcon Centurion Vision and Zeiss Quatera 700 systems. Peak surge and duration was measured after an occlusion break. Quatera tested in flow and vacuum priority modes. Vacuum limits ranged from 300 to 700 mm Hg with intraocular pressure (IOP) set at 30 mm Hg, 55 mm Hg, and 80 mm Hg. IOP vs incision leakage rates of 0 to 15 cc/min and passive vacuum were measured. RESULTS: At 30 mm Hg IOP set point and vacuum limits ranging 300 to 700 mm Hg, the surge duration time after occlusion break ranged 419 to 1740 milliseconds (ms) for Centurion, 284 to 408 ms for Quatera in the flow mode, and 282 to 354 ms for Quatera in the vacuum mode. At 55 mm Hg, values ranged 268 to 1590 ms for Centurion, 258 to 471 ms for Quatera in the flow mode, and 239 to 284 ms for Quatera in the vacuum mode. At 80 mm Hg, values were 243 to 1520 ms for Centurion, 238 to 314 ms for Quatera in the flow mode, and 221 to 279 ms in the vacuum mode. Centurion exhibited slightly less peak surge than the Quatera. At 55 mm Hg: incision leakage rates 0 to 15 cc/min, Quatera held the IOP within ±2 mm Hg of target; Centurion was unable to hold IOP target allowing a 11.7 mm Hg decrease with 32% higher passive vacuum. CONCLUSIONS: Quatera demonstrated slightly higher surge peak values and notably shorter surge duration times after occlusion break than Centurion. Quatera demonstrated better incision leakage compensation and lower passive vacuum than Centurion.