Objective: To determine after implantation of a glaucoma aqueous drainage device whether fluid is present around the equatorial plate and to measure the bleb size around the plate.
Methods: 41 plates in 41 patients (41 eyes) with refractory glaucoma who had undergone human aqueous drainage (HAD) implantation underwent standardized echography (both A- and B-scan examinations) after a mean postoperative follow-up period, 5.2 months. According to the bleb height and the fluid underlying and/or overlying the plate, the blebs were divided into five grades and two types to evaluate their functions.
Results: Of the 41 cases examined with echography, 35 (85%) were associated with posterior blebs, 2 (5%) had no associated posterior blebs, and the posterior bleb in 4 (10%) cases was not certain. The percentage of the presence of filtering bleb around the plate was 15%, 12%, 29%, 37%, and 7% in Grade 0 to IV group, and 11% and 89% in type A and B, respectively. There was no significant correlation between the bleb size and the level of intraocular pressure control.
Conclusion: Standardized ocular echography is helpful in the postoperative management of failed cases who have undergone HAD implantation because it can demonstrate the presence or absence of blebs and characterize them.