title: Comparison of the effects of 23-gauge and 25-gauge microincision vitrectomy blade designs on incision architecture.
abstract: OBJECTIVE
  To compare the effects of different 23- and 25-gauge microincision vitrectomy trocar cannula entry systems on incision architecture.
  
  
  METHODS
  We tested one ridged microvitreoretinal (MVR), one non-ridged MVR, one pointed beveled, and one round-tipped beveled blade (n=10 per blade design per incision type). Each blade's straight and oblique incision architecture was assessed in a silicone disc simulating the sclera. Wound leakage under pressure and endoscopic observations were conducted on sclerotomy sites of isolated porcine eyes (n=4 per blade design) after simulated vitrectomy.
  
  
  RESULTS
  Differences in blade design created distinct incision architecture. Incisions were linear with the ridged MVR blade, flattened "M-shaped" with the non-ridged MVR blade, asymmetrical chevron-shaped with the pointed beveled blade, and curved with the round-tipped beveled blade. With the exception of oblique entry incision thickness, both MVR blade designs created thinner incisions than the beveled blades at entry and exit sites. Only the ridged MVR blade created incisions with no leakage. Vitreous incarceration was observed with all trocar cannula systems.
  
  
  CONCLUSIONS
  Wound closure in porcine eyes was similar with all blades despite differences in incision architecture. Wound leakage occurred at low to moderate infusion pressures with most blades; no wound leakage was observed with ridged MVR blades.
authors.affiliation: Kyorin Eye Center, School of Medicine, Kyorin University, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Inoue
authors.affiliation: Alcon Research, Ltd., Irvine, CA, USA.
authors.forename: Dina Joy K
authors.initials: DJ
authors.lastname: Abulon
authors.affiliation: Kyorin Eye Center, School of Medicine, Kyorin University, Tokyo, Japan.
authors.forename: Akito
authors.initials: A
authors.lastname: Hirakata
keywords: entry system; incision closure; leakage; pars plana incision; sclerotomy; trocar blade