A comparison of the polypropylene plate Ahmed glaucoma valve to the silicone plate Ahmed glaucoma flexible valve.

PURPOSE

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.

DESIGN

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.