The Ahmed Versus Baerveldt study: one-year treatment outcomes.

Objective

To report the 1-year treatment outcomes of the Ahmed Versus Baerveldt (AVB) Study.

Design

Multicenter randomized clinical trial.

Participants

A total of 238 patients were enrolled in the study, including 124 in the Ahmed group and 114 in the Baerveldt group.

Methods

Patients aged 18 years or older with uncontrolled glaucoma refractory to medicinal, laser, and surgical therapy were randomized to undergo implantation of an Ahmed-FP7 valve (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA), to be followed for 5 years.

Main outcome measures

The primary outcome measure was failure, defined as intraocular pressure (IOP) out of target range (5-18 mmHg with ≥ 20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, additional glaucoma procedures, or loss of light perception. Secondary outcome measures included IOP, medication use, visual acuity, complications, and interventions.

Results

There were no significant differences in baseline ocular or demographic characteristics between the study groups with the exception of sex. Preoperatively, the study group had a mean IOP of 31.4 ± 10.8 mmHg on a mean of 3.1 ± 1.0 glaucoma medications with a median Snellen acuity of 20/100. The cumulative probability of failure a 1-year was 43% in the Ahmed group and 28% in the Baerveldt group (P = 0.02). The mean IOP at 1 year was 16.5 ± 5.3 mmHg in the Ahmed group and 13.6 ± 4.8 mmHg in the Baerveldt group (P < 0.001). The mean number of glaucoma medications required was 1.6 ± 1.3 in the Ahmed group and 1.2 ± 1.3 in the Baerveldt group (P = 0.03). Visual acuity was similar in both groups at all visits in the first year (P = 0.66). In the first year after surgery, there were a similar number of patients who experienced postoperative complications in the 2 groups (45% Ahmed, 54% Baerveldt, P = 0.19), but a greater number of patients in the Baerveldt group required interventions (26% Ahmed vs. 42% Baerveldt, P = 0.009).

Conclusions

The Baerveldt-350 group had a higher success rate than the Ahmed-FP7 group after 1 year of follow-up, but required a greater number of interventions.

Financial disclosure(s): Proprietary or commercial disclosure may be found after the references.