Intraoperative performance and postoperative outcome comparison of longitudinal, torsional, and transversal phacoemulsification machines

PURPOSE: To compare the intraoperative performance and postoperative outcomes of 3 phacoemulsification machines that use different modes. SETTING: Kensington Eye Institute, Toronto, Ontario, Canada. DESIGN: Comparative case series. METHODS: This chart and video review comprised consecutive eligible patients who had phacoemulsification by the same surgeon using a Whitestar Signature Ellips-FX (transversal), Infiniti-Ozil-IP (torsional), or Stellaris (longitudinal) machine. RESULTS: The review included 98 patients. Baseline characteristics in the groups were similar; the mean nuclear sclerosis grade was 2.0 +/- 0.8. There were no significant intraoperative complications. The torsional machine averaged less phacoemulsification needle time (83 +/- 33 seconds) than the transversal (99 +/- 40 seconds; P=.21) or longitudinal (110 +/- 45 seconds; P=.02) machines; the difference was accentuated in cases with high-grade nuclear sclerosis. The torsional machine had less chatter and better followability than the transversal or longitudinal machines (P<.001). The torsional and longitudinal machines had better anterior chamber stability than the transversal machine (P<.001). Postoperatively, the torsional machine yielded less central corneal edema than the transversal (P<.001) and longitudinal (P=.04) machines, corresponding to a smaller increase in mean corneal thickness (torsional 5%, transversal 10%, longitudinal 12%; P=.04). Also, the torsional machine had better 1-day postoperative visual acuities (P<.001). CONCLUSIONS: All 3 phacoemulsification machines were effective with no significant intraoperative complications. The torsional machine outperformed the transversal and longitudinal machines, with a lower mean needle time, less chatter, and improved followability. This corresponded to less corneal edema 1 day postoperatively and better visual acuity.