Evaluation of Early Postoperative Intraocular Pressure for Success after Ex-Press Surgery

Abstract

Aim: The aim of this study is to identify target levels of early postoperative intraocular pressure (IOP) associated with successful trabeculectomy using an Ex-Press glaucoma shunt.

Materials and methods: This was a retrospective single-facility study. We enrolled 158 glaucoma patients who underwent trabeculectomy with Ex-Press and were followed for >1 year, and investigated risk factors for the failure of Ex-Press surgery. We examined age, sex, central corneal thickness (CCT), number of preoperative glaucoma medications, simultaneous performance of cataract surgery, history of trabeculotomy, hypertension (HT), diabetes mellitus (DM), subtype of glaucoma, and early postoperative IOP (minimum, 2 weeks, 1 month, and 3 months).

Results: Ex-Press surgery could significantly decrease IOP. Success rates at 1, 2, 3, and 4 years were 91.1, 86.1, 82.5, and 78.1%, respectively. Factors significantly affecting the success rate included age, the number of preoperative glaucoma medications, and early postoperative IOP. The IOP cutoff values of minimum IOP for the success of Ex-Press surgery was 5 mm Hg.

Conclusions: Younger age, a high number of preoperative glaucoma medications, and high IOPs in the early postoperative period were found to be the risk factors for failure of Ex-Press surgery. Considering hypotonic complications, it is desirable to control the minimum IOP from 3-5 mm Hg within 2 weeks after surgery. According to our calculations, target IOPs at 2 weeks, 1 month, and 3 months after Ex-Press surgery should be 8 mm Hg, 10 mm Hg, and 14 mm Hg, respectively.

Clinical significance: We thought that Ex-Press surgery might require lower IOP in the early postoperative period than conventional trabeculectomy.

How to cite this article: Tojo N, Hayashi A, et al. Evaluation of Early Postoperative Intraocular Pressure for Success after Ex-Press Surgery. J Curr Glaucoma Pract 2019;13(2):55-61.

Keywords: Choroidal detachment; Ex-Press; Target intraocular pressure; Trabeculectomy.

Fig. 1

Kaplan–Meier survival plots of all cases for qualified success. The success was defined as postoperative IOP ≤21 mm Hg, at least 20% IOP reduction from baseline in any two consecutive visits after 3 months, and no secondary glaucoma or lens surgery

Figs 2A to D

(A) Kaplan–Meier survival plots comparing minimum IOP ≤5 mm Hg (128 eyes) and minimum IOP >6 mm Hg (30 eyes) within 2 weeks after Ex-Press surgery. The group of postoperative IOP ≤5 mm Hg (bold line) was significantly better than the group of postoperative IOP >6 mm Hg (normal line) (p = 0.0118); (B) Kaplan–Meier survival plots comparing postoperative IOP ≤8 mm Hg (138 eyes) and postoperative IOP >9 mm Hg (20 eyes) at 2 weeks after Ex-Press surgery. The group of postoperative IOP ≤8 mm Hg (bold line) was significantly better than the group of postoperative IOP >9 mm Hg (normal line) (p = 0.0006); (C) Kaplan–Meier survival plots comparing postoperative IOP ≤10 mm Hg (104 eyes) and postoperative IOP >11 mm Hg (54 eyes) at 1 month after Ex-Press surgery. The group of postoperative IOP ≤10 mm Hg (bold line) was significantly better than the group of postoperative IOP >11 mm Hg (normal line) (p = 0.0354); (D) Kaplan–Meier survival plots comparing postoperative IOP ≤14 mm Hg (120 eyes) and postoperative IOP >15 mm Hg (35 eyes) at 3 months after Ex-Press surgery. The group of postoperative IOP ≤14 mm Hg (bold line) was significantly better than the group of postoperative IOP >15 mm Hg (normal line) (p < 0.0001)