Why carry out this study?

While the use of glaucoma drainage devices (GDD) has increased in the surgical management of glaucoma, their success is limited by high 5-year failure rates. Studies have shown that fibrotic encapsulation at the implant site is the most common cause of device failure as it results in increased outflow resistance and inadequate control of intraocular pressure.

The purpose of the study was to quantify the effects of modified Ahmed glaucoma valves® (AGV) with anti-fibrotic plate coatings or a plate surface micro-pattern on outflow resistance and histologic tissue response.

What was learned from this study?

Hydrostatic pressures were significantly lower in all modified AGVs, and fibrotic encapsulation was significantly lower in the heparin plate coating and micro-patterned surface when compared to the control.

Modified AGVs with plate coatings as well as AGVs with micro-patterned plates appear to reduce postoperative fibrotic encapsulation and aqueous outflow resistance by altering the tissue response to implanted materials.