title: Study of intraocular pressure after 23-gauge and 25-gauge pars plana vitrectomy randomized to fluid versus air fill.
abstract: OBJECTIVE
  To determine if a difference in intraocular pressure (IOP) exists after small-gauge pars plana vitrectomy randomized to fluid versus 80% sterile air fill.
  
  
  METHODS
  Ninety-two eyes undergoing 23-gauge and 25-gauge transconjunctival pars plana vitrectomy were randomized to fluid versus air fill, and IOP was measured at 5 different time points.
  
  
  RESULTS
  There is no difference in the mean IOP for eyes undergoing small-gauge pars plana vitrectomy randomized to fluid versus air fill after vitrectomy. Using 23-gauge instrumentation, the mean immediate and 2-hour postoperative IOPs were statistically lower than the mean preoperative IOP. The mean Postoperative Day 1 and Week 1 IOPs were statistically higher than the mean immediate postoperative IOP. Using 25-gauge instrumentation, the mean IOP was not statistically different at any time points in the 2 groups. When comparing 23-gauge with 25-gauge instrumentation, the immediate postoperative IOP was statistically lower and the rate of suture closure for sclerotomies was higher for 23-gauge vitrectomy.
  
  
  CONCLUSIONS
  When performing 23-gauge or 25-gauge pars plana vitrectomy, there was no difference in mean IOP for fluid- versus air-filled eyes. However, the mean IOP in the immediate postoperative period was statistically lower, and there was a higher rate of suture closure for 23-gauge compared with 25-gauge instrumentation.
authors.affiliation: Associated Retinal Consultants, Beaumont Eye Institute, Royal Oak, Michigan, USA. lawrence.y.ho@gmail.com
authors.forename: Lawrence Y
authors.initials: LY
authors.lastname: Ho
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Garretson
authors.forename: Tushar M
authors.initials: TM
authors.lastname: Ranchod
authors.forename: Mamtha
authors.initials: M
authors.lastname: Balasubramaniam
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Ruby
authors.forename: Antonio
authors.initials: A
authors.lastname: Capone
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Drenser
authors.forename: George A
authors.initials: GA
authors.lastname: Williams
authors.forename: Tarek S
authors.initials: TS
authors.lastname: Hassan
mesh_terms: D000368:Aged; D000388:Air; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D007906:Lens Subluxation / Q000601:surgery; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D015814:Ocular Hypotension / Q000175:diagnosis; D011446:Prospective Studies; D012164:Retinal Diseases / Q000601:surgery; D012599:Sclerostomy; D013536:Suture Techniques; D014065:Tonometry, Ocular; D014792:Visual Acuity / Q000502:physiology; D014821:Vitrectomy / Q000295:instrumentation / Q000379:methods*