The Hypertensive Phase after Glaucoma Drainage Implant Surgery

Abstract

Abstract: : Purpose: To investigate the hypertensive phase (HP) in patients undergoing glaucoma drainage implant surgery. Methods: A chart review of all patients who underwent placement of an Ahmed Glaucoma Valve for glaucoma was conducted. Eyes with a follow-up of at least 3 months were included. Main outcome measures were occurrence and resolution of the HP and tonometric success at final follow-up. HP was defined as IOP > 21 mmHg during the first 3 months after surgery. Resolution of HP was described as an IOP reduction of 3 mmHg or more with the same or fewer number of medications 6-12 months after surgery compared to the IOP 3-6 months following surgery. Tonometric success was defined as an IOP < 22 mmHg and a 20% reduction of the preoperative IOP at the final follow-up. Results: A total of 156 eyes (of 139 patients) with a mean (+SD) age of 60.1 + 21.4 years were included. An HP was observed in 88 eyes (56.4%). It occurred after a mean of 5.0 weeks (median: 4 weeks; range: 2-12 weeks) with an average (+ SD) peak IOP of 29.9 (+ 7.5) mmHg. Fifteen out of 53 eyes (28%) that had data available during the required periods had resolution of the HP. Kaplan-Meier survival analysis showed a trend for a higher failure rate in eyes with an HP compared to those without an HP (not statistically significant; P > 0.05; log-rank test). Conclusion: A hypertensive phase occurs frequently after implantation of Ahmed Glaucoma Valve. However, it resolves in only a minority of eyes. The majority of the eyes with an HP had no significant improvement of IOP and continued to require the same number of glaucoma medications as they did during the HP.

Keywords: clinical (human) or epidemiologic studies: out • intraocular pressure