Evaluation of the hypertensive phase after insertion of the Ahmed Glaucoma Valve

To investigate the postoperative hypertensive phase (HP) in patients undergoing glaucoma drainage implant surgery.

Interventional case series.

A retrospective chart review of 156 consecutive eyes (139 patients) who underwent placement of an Ahmed Glaucoma Valve (AGV) with a follow-up of >or=3 months was performed. Main outcome measures were occurrence and resolution of the HP and intraocular pressure (IOP) control. The HP was defined as IOP > 21 mm Hg during the first 3 months after surgery. Resolution of the HP was defined as an IOP < 22 mm Hg and an IOP reduction of 3 mm Hg with the same or fewer number of glaucoma medications.

An HP was observed in 88 eyes (56%). It occurred after a mean of 5.0 weeks (median, 4 weeks; range, 1-13 weeks) with an average (+/- standard deviation) peak IOP of 30.1 (+/- 7.5) mm Hg. Resolution of the HP occurred in 19 of 68 eyes (28%) with available data. Eyes with an HP had a higher mean IOP and needed more medications 6 to 12 months after surgery than eyes without an HP (17.2 +/- 5.6 vs 14.3 +/- 5.8 mm Hg; P =.012 and 1.7 +/- 1.2 vs 0.3 +/- 0.6 medications; P <.001, respectively).

A hypertensive phase occurs frequently after implantation of the AGV. However, it resolves in only a minority of eyes. The majority of eyes with an HP have no significant improvement of IOP control and continue to require the same number of glaucoma medications as they did during the HP.