title: Intraoperative performance and postoperative outcome comparison of longitudinal, torsional, and transversal phacoemulsification machines.
abstract: OBJECTIVE
  To compare the intraoperative performance and postoperative outcomes of 3 phacoemulsification machines that use different modes.
  
  
  METHODS
  Kensington Eye Institute, Toronto, Ontario, Canada.
  
  
  METHODS
  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.
authors.affiliation: Yale University School of Medicine, New Haven, Connecticut, USA.
authors.forename: Panos G
authors.initials: PG
authors.lastname: Christakis
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Braga-Mele
mesh_terms: D000368:Aged; D015715:Corneal Edema / Q000503:physiopathology / Q000517:prevention & control; D005260:Female; D006801:Humans; D007431:Intraoperative Complications; D019654:Lens Implantation, Intraocular; D008297:Male; D018918:Phacoemulsification / Q000295:instrumentation*; D011183:Postoperative Complications; D019591:Pseudophakia / Q000503:physiopathology; D012189:Retrospective Studies; D016896:Treatment Outcome; D055675:Viscosupplements / Q000008:administration & dosage; D014792:Visual Acuity / Q000502:physiology
chemical_list: D055675:Viscosupplements