Clinical and Biological Evaluations of Biodegradable Collagen Matrices for Glaucoma Drainage Device Implantation.

Purpose: To characterize the clinical and biological properties of biodegradable collagen matrices (BCMs) for possible glaucoma drainage device implantation.

Methods: A total of 68 refractory glaucoma eyes, followed up postoperatively for at least 6 months, were consecutively enrolled after retrospective chart review. The BCM-augmented Ahmed valve implantations (BAAVI) using our Ologen-6 and Ologen-7 valves were performed and compared with a conventional method. Complete surgical success was defined as an IOP of ≤21 mm Hg (IOP 1) or ≤17 mm Hg (IOP 2) without antiglaucoma medications. Qualified success was defined as an IOP ≤21 mm Hg with or without antiglaucoma medications. The biological properties of each BCM were assessed by enzymatic degradation rates via collagenase under ocular physiological conditions.

Results: The mean ages and preoperative IOPs were similar for the groups. In the conventional, BAAVI with Ologen-6, and BAAVI with Ologen-7 groups, complete success rates with target IOP 1 were 29.2%, 40.0%, and 66.7%; those with target IOP 2 were 12.5%, 30.0%, and 45.8%; qualified success rates were 45.8%, 55.0%, and 75.0%, respectively. The enzymatic degradation rate of Ologen-7 was significantly slower than that of Ologen-6 (12.5 × 10-3 vs. 28.8 × 10-3).

Conclusions: The surgical success rate was highest in the Ologen-7 BAAVI group, with the lowest dependency on postoperative antiglaucoma medication use compared with the conventional and Ologen-6 BAAVI groups. The clinical results correlated with the different biological and physicochemical properties based on the degree of enzymatic degradation and on the structural morphology.