Effect of a Pericardium Graft Inserted Adjacent to the Endplate in the Ahmed Glaucoma Valve Implantation

Abstract

The surface area of encapsulation around the Ahmed glaucoma valve (AGV) endplate is a critical factor in the surgical outcome as it is associated with the degree of IOP reduction. We investigated the surgical outcome of AGV implantation with an additional pericardium graft inserted adjacent to the endplate, with the intent of expanding the surface area of encapsulation. We enrolled 92 patients (92 eyes) who underwent AGV implantation. Of them, 50 patients underwent conventional surgery (termed the without-expansion group), and 42 received an additional an 8 × 6 mm pericardium graft inserted adjacent to the AGV endplate at the sub-Tenon’s space (with-expansion). The hypertensive phase was classified as mild (>21 mmHg), moderate (>25 mmHg), and severe (>30 mmHg). Six months post-surgery, the with-expansion group exhibited a lower IOP (14.90 ± 4.27 mmHg) and lower peak IOP (22.29 ± 4.95 mmHg) than the without-expansion group (17.56 ± 4.88 mmHg and 25.06 ± 6.18 mmHg, p = 0.008 and p = 0.021, respectively). The with-expansion group exhibited a relatively low rate of moderate (16.7%) and severe (4.8%) hypertensive phases compared to the without-expansion group (40.0% and 20.0%, with p = 0.014 and p = 0.031, respectively). The additional pericardium graft was associated with a reduced occurrence of moderate hypertensive phase in both univariate and multivariate analysis logistic regression analyses (p = 0.017 and p = 0.038, respectively). Endplate surface area expansion using an additional pericardium graft reduced the occurrence of moderate and severe hypertensive phases, and lower postoperative 6-month IOP could be achieved.