title: A comparison of the polypropylene plate Ahmed glaucoma valve to the silicone plate Ahmed glaucoma flexible valve.
abstract: OBJECTIVE
  To compare surgical outcomes following implantation of the polypropylene plate Ahmed glaucoma valve (AGV) (S-2) and the newer silicone plate AGV (FP-7) with minimum 12 months follow-up in patients with intractable glaucoma.
  
  
  METHODS
  Retrospective chart review of 25 eyes of 22 patients who underwent FP-7 and 26 eyes of 22 patients who underwent S-2 AGV implantation by a single surgeon. Main outcome measures included surgical outcomes in terms of intraocular pressure (IOP) control, hypertensive phase, and postoperative complications.
  
  
  RESULTS
  There were no significant differences in diagnoses, pre-and postoperative IOP, pre- and postoperative visual acuities at all time points, and in the number of pre- and postoperative medications between the groups. Significant IOP reductions occurred after FP-7 implantation (29.6 +/- 13.1 to 12.1 +/- 3.4, p < 0.001) and S-2 implantation (31.4 +/- 11.7 to 16.1 +/- 5.7, p < 0.001). The FP-7 group had a statistically lower IOP compared to the S-2 group at 6 (p<0.05), 9 (p<0.01), and 12 months (p<0.01). There was no significant difference in the hypertensive phase between the two groups (p=0.41).
  
  
  CONCLUSIONS
  FP-7 model silicone plate AGV resulted in lower IOP compared to the older S-2 polypropylene plate AGV at 1 year. This may suggest that the plate material may influence clinical outcome.
authors.affiliation: Department of Ophthalmology, Tulane University Health Sciences Center, New Orleans, LA 70112-2699, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Hinkle
authors.forename: D
authors.initials: D
authors.lastname: Zurakowski
authors.forename: R S
authors.initials: RS
authors.lastname: Ayyala
mesh_terms: D018463:Filtering Surgery / Q000379:methods*; D005500:Follow-Up Studies; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011126:Polypropylenes; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000295:instrumentation*; D012189:Retrospective Studies; D012826:Silicone Elastomers; D016896:Treatment Outcome; D014792:Visual Acuity
chemical_list: D011126:Polypropylenes; D012826:Silicone Elastomers