title: Effect of microkeratome suction duration on corneal flap thickness and incision angle.
abstract: OBJECTIVE
  To determine the effect of suction duration on corneal flap thickness and incision angle of the cut margin created by a microkeratome in a porcine eye.
  
  
  METHODS
  Thirty porcine eyes were randomly assigned to three groups according to different suction duration: group 1 (10 sec), group 2 (35 sec), and group 3 (60 sec). The Hansatome microkeratome with a #160 plate and 8.5-mm-diameter suction ring was used to create a corneal flap with a diameter of 8.5 millimeters. Corneal flap thickness was measured by automated ultrasonic pachymetry, and the incision angle was assessed by measuring the angle of a sagittal section of the cornea using image analysis software.
  
  
  RESULTS
  Mean corneal flap thickness in groups 1 (10 sec), 2 (35 sec), and 3 (60 sec) was 87.8 +/- 22.0 microm, 116.0 +/- 7.0 microm, and 127.2 +/- 16.8 microm, respectively. There was a statistically significant difference between groups 1 (10 sec) and 2 (35 sec) (P=.005) and groups 1 and 3 (P=.004). The mean incision angle in groups 1, 2, and 3 was 34.8 +/- 9.0 degrees, 44.4 +/- 16.1 degrees, and 48.24 +/- 15.3 degrees, respectively. A statistically significant difference was found between groups 1 (10 sec) and 2 (35 sec) (P=.044) and groups 1 (10 sec) and 3 (60 sec) (P<.001).
  
  
  CONCLUSIONS
  In laser in situ keratomileusis in porcine eyes, an increase in suction duration resulted in a thicker flap and greater incision angle.
authors.affiliation: Department of Ophthalmology, Yonsei Institute of Vision Research, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Yul
authors.initials: KY
authors.lastname: Seo
authors.forename: Xiu H
authors.initials: XH
authors.lastname: Wan
authors.forename: Jae W
authors.initials: JW
authors.lastname: Jang
authors.forename: Jae Bum
authors.initials: JB
authors.lastname: Lee
authors.forename: Moon J
authors.initials: MJ
authors.lastname: Kim
authors.forename: Eung Kweon
authors.initials: EK
authors.lastname: Kim
mesh_terms: D000818:Animals; D003315:Cornea / Q000601:surgery*; D019781:Corneal Topography; D020731:Keratomileusis, Laser In Situ; D018715:Microscopy, Video; D013508:Ophthalmologic Surgical Procedures; D013396:Suction; D013524:Surgical Flaps / Q000473:pathology*; D013552:Swine; D013997:Time Factors