title: Analyses of cutting and aspirating properties of vitreous cutters with high-speed camera.
abstract: OBJECTIVE
  To investigate the cutting and aspirating properties of eight vitreous cutters under different conditions and to analyze the factors determining these properties.
  
  
  METHODS
  Commercially available 20-gauge (20-G), 23-G, and 25-G pneumatic vitreous cutters were evaluated. The areas of the inner tube and cutting port were measured with a microscope and 3D-CAD software. The total opening area/s of the cutting port was determined by photographing the movements of the cutter blade with a high-speed camera. The total volume of balanced salt solution aspirated/s was measured.
  
  
  RESULTS
  The inner tube areas ranged from 0.350-0.352 mm2 for the 20-G, 0.169-0.196 mm for the 23-G, and 0.128-0.129 mm2 for the 25-G cutters. The port areas ranged from 0.254 to 0.306 mm2 for the 20-G, 0.122 to 0.173 mm2 for the 23-G, and 0.066 to 0.125 mm2 for the 25-G cutters. High-speed camera analyses revealed that the total opening area was determined not only by the port area but also by the duty cycle, and that the latter varied among the cutters even under the same cutting speed. There was a positive correlation (R2 >0.88) between total opening area/s and total aspirated volume/s.
  
  
  CONCLUSIONS
  Larger cutting port areas and higher duty cycles are associated with higher aspirated volumes of vitreous cutters.
authors.affiliation: Department of Applied Visual Science, Osaka University Medical School, Japan.
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Sato
authors.forename: Shunji
authors.initials: S
authors.lastname: Kusaka
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Oshima
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujikado
mesh_terms: D006801:Humans; D008866:Microsurgery / Q000379:methods; D010781:Photography / Q000379:methods*; D013396:Suction; D014821:Vitrectomy / Q000295:instrumentation*; D014822:Vitreous Body / Q000601:surgery*