Early Aqueous Suppressant Therapy on Hypertensive Phase Following Glaucoma Drainage Device Procedure: A Randomized Prospective Trial.

Abstract

To prospectively evaluate the effect of early aqueous suppression (therapy) on hypertensive phase (HP) and intraocular pressure (IOP) control after implantation of silicone Ahmed glaucoma valve (AGV). Patients who underwent AGV implantation were randomized to initiate therapy (including β-blockers, α-agonists, or carbonic anhydrase inhibitors) when postoperative IOP>10 mm Hg (low-IOP initiation group) or >17 mm Hg (moderate-IOP initiation group). HP was defined as an IOP>21 mm Hg during the first 6 postoperative months, after an initial IOP reduction to <22 mm Hg in the first postoperative week. Primary outcome measures included the occurrence of HP and IOP control. Fifty-two eyes (50 patients) underwent AGV implantation. Average follow-up was 21.9±10.7 months. HP was observed in 21 eyes (40.4%) with average peak IOP of 30±8 mm Hg, onset at 32±30 days, and duration of 15±32 days. One year postoperatively, those eyes with HP had higher IOP than eyes that did not develop HP (15.1±5.2, 11.4±4.3, respectively; P=0.021) and required more additional glaucoma surgeries (28.6%, 3.2%, respectively; P=0.013). The peak IOP at week 3 postoperatively in the low-IOP initiation group (26 eyes) was significantly lower than in the moderate-IOP initiation group (26 eyes; 15.7±3.6, 20.6±8.9, respectively; P=0.012). Eyes with therapy started after HP onset had significantly higher postoperative IOP from 2 to 4 months. Therapy initiated before the development of HP was not associated with a higher complication rate. Aqueous suppression initiated in the early postoperative period while IOPs were still in the low-teens and was able to reduce the incidence of IOP spike associated with the HP without an increased complication rate.