Glaucoma implants don't have staying power

The Ahmed glaucoma valve (AGV) and the Molteno single plate implant (MSPI) may provide good early and intermediate-term control of intraocular pressure (IOP) in patients with neovascular glaucoma (NVG), but do not achieve the same success when implanted for long periods, according to a study published in the January issue of Eye.

I.S. Yalvac and colleagues from the Ankara Education and Research Hospital, Turkey, enrolled 65 patients with NVG to receive either an AGV (38 eyes) or an MSPI (27 eyes).

In the AGV group, the cumulative probabilities of success were 63.2%, 56.2%, 43.2%, 37.8% and 25.2% at years one, two, three, four and five, respectively. In the MSPI group, the cumulative probabilities of success were 37%, 29.6%, 29.6%, 29.6% and 29.6% over the same five- year period. Preoperative visual acuity (<2/200), diagnosis of diabetes mellitius and preoperative IOP (35 mmHg) were found to be poor predictors of surgical success.

From these results, the authors conclude that, although the implants may be successful at controlling IOP in the short- and intermediate-term, they are not successful over longer periods.