title: AXIAL ROTATION VITRECTOMY: Back to the Future? the Fluidics of a Prototype Vitreous Cutter Probe.
abstract: OBJECTIVE
  To characterize the fluidics of axial rotating vitreous cutter probe (RT) compared with the standard guillotine (regular blade), when tested in Balanced Salt Solution (Alcon Laboratories, Forth Worth, TX).
  
  
  METHODS
  RT and regular blade (RB) cutter probes connected to the same vitrectomy console used a peristaltic pump. The authors measured instantaneous flow through aspiration tubing proximal to the handpiece, fluid velocity, and acceleration at the port by means of particle image velocimetry.
  
  
  RESULTS
  Average flow at aspiration tubing of RT and RB did not vary significantly. Regular blade probes produced higher instantaneous flow fluctuation than RT at any considered cut rate (RB 1,600 6.4 ± 5.3 mL/minute; RB 3,000 11.8 ± 6.3 mL/minute; RT 1,600 0.9 ± 0.7 mL/minute, and RT 3,000 1.8 ± 0.8 mL/minute, respectively. P < 0.001 in all cases). Regular blade also yield significantly higher fluid velocity at cutter port compared with RT (RB 1,600 85.8 ± 70.1 mm/second; RB 3,000 81.6 ± 66.4 mm/second; RT 1,600 71.9 ± 40.3 mm/second; and RT 3,000 32.9 ± 20.8 mm/second. P < 0.001 in all cases). Fluid acceleration at the cutter port was higher when the RB was used (RB 1,600 26.85 ± 30.18 mm/second; RB 3,000 33.76 ± 34.09 mm/second; RT 1,600 24.01 ± 21.94 mm/second; and RT 3,000 16.62 ± 17.87 mm/second. P < 0.001 in all cases).
  
  
  CONCLUSIONS
  RT blade design causes less instantaneous flow fluctuation within the aspiration tubing, and also lower fluid velocity and lower acceleration at the cutter port. Fluidics suggests a safer cutting action and a reduced risk of retinal incarceration.
authors.affiliation: *Department of Neurosciences, Azienda Ospedaliera Universitaria San Martino IRCCS, Genoa, Italy; †University of Cagliari, DICAAT, Cagliari, Italy; ‡Optikon 2000 Inc., Rome, Italy; and §Fondazione G.B. Bietti IRCCS, Rome, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Rossi
authors.forename: Giorgio
authors.initials: G
authors.lastname: Querzoli
authors.forename: Giampiero
authors.initials: G
authors.lastname: Angelini
authors.forename: Carlo
authors.initials: C
authors.lastname: Malvasi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Rossi
authors.forename: Mario
authors.initials: M
authors.lastname: Morini
authors.forename: Mario
authors.initials: M
authors.lastname: Iossa
authors.forename: Guido
authors.initials: G
authors.lastname: Ripandelli
mesh_terms: D000085:Acetates; D004338:Drug Combinations; D006801:Humans; D057446:Hydrodynamics; D008903:Minerals; D012212:Rheology; D012965:Sodium Chloride; D014821:Vitrectomy / Q000295:instrumentation*; D014822:Vitreous Body / Q000601:surgery*
chemical_list: D000085:Acetates; C030660:BSS solution; D004338:Drug Combinations; D008903:Minerals; D012965:Sodium Chloride