A Comparison of Postoperative Complications From Pressure-Ridge Molteno Implants Versus Molteno Implants With Suture Ligation

Abstract

The pressure-ridge Molteno implant incorporates a ridge on the proximal episcleral plate to limit aqueous outflow during the immediate postoperative period. This modification is intended to decrease the high incidence of postoperative hypotony and flat anterior chambers following Molteno tube implantation, while avoiding the pressure spikes that can occur with suture ligation of the Molteno tube. This study was devised to compare postoperative intraocular pressure control and complications associated with pressure-ridge Molteno implantation versus a standard Molteno implantation with suture ligation of the tube. Thirty eyes were prospectively randomized to receive either a pressure-ridge, double-plate Molteno implant or a standard, double-plate Molteno Molteno implant with suture ligation of the tube. Postoperative intraocular pressure was significantly higher at day 1 and week 2 in the suture-ligation implant group, although the final pressure at 12 weeks was not different between the two groups. Six of 15 eyes from the pressure-ridge implant group experienced shallow or flat anterior chambers with hypotony, whereas 5 of 15 eyes from the suture-ligation implant group had significant postoperative pressure spikes. Because the ridge effect is unpredictable, further modifications are necessary to prevent postoperative hypotony.