title: Phacoemulsification tip vacuum pressure: Comparison of 4 devices.
abstract: OBJECTIVE
  To determine the vacuum pressure generated by 4 phacoemulsification devices measured at the phacoemulsification tip.
  
  
  METHODS
  University ophthalmology department.
  
  
  METHODS
  The effective vacuum pressures generated by the Sovereign (AMO), Millennium (Bausch & Lomb), Legacy AdvanTec (Alcon Laboratories), and Infiniti (Alcon Laboratories) phacoemulsification machines were measured with a device that isolated the phacoemulsification tip in a chamber connected to a pressure gauge. The 4 machines were tested at multiple vacuum limit settings, and the values were recorded after the foot pedal was fully depressed and the pressure had stabilized. The AdvanTec and Infiniti machines were tested with and without occlusion of the Aspiration Bypass System (ABS) side port (Alcon Laboratories). The Millennium machine was tested using venturi and peristaltic pumps.
  
  
  RESULTS
  The machines generated pressures close to the expected at maximum vacuum settings between 100 mm Hg and 500 mm Hg with few intermachine variations. There was no significant difference between pressures generated using 19- or 20-gauge tips (Millennium and Sovereign). The addition of an ABS side port decreased vacuum by a mean of 12.1% (P < .0001).
  
  
  CONCLUSIONS
  Although there were some variations in vacuum pressures among phacoemulsification machines, particularly when an aspiration bypass tip was used, these discrepancies are probably not clinically significant.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA.
authors.forename: Marielle
authors.initials: M
authors.lastname: Payne
authors.forename: Dan
authors.initials: D
authors.lastname: Georgescu
authors.forename: Aaron N
authors.initials: AN
authors.lastname: Waite
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Olson
mesh_terms: D018918:Phacoemulsification / Q000295:instrumentation*; D011312:Pressure; D014618:Vacuum