A comparison of glaucoma drainage implant tube coverage

Purpose: Surgeons may use various materials, including donor sclera, dura, or pericardium grafts to cover glaucoma drainage implant tubes, prior to repositioning conjunctiva. We reviewed our experience with these materials. Patients and Methods: Sixty-four eyes with at least 24 months follow-up status post glaucoma drainage implant surgery were evaluated for signs of tube erosion, as well as patch graft thinning, after initial placement of donor sclera (23), dura (18), or pericardium (23) patch grafts. Results: Sixty-two eyes required no intervention for conjunctival and patch graft melting with subsequent tube erosion. Three cases (two eyes) of erosion requiring reoperation (1-dura at 6 months, 1-sclera at 15 months, and in the same eye 21 months later, 1-pericardium) were noted. Significant thinning of the donor patch graft such that the tube was visible beneath intact conjunctiva ocurred in 6 out of 23 donor sclera eyes, 4 out of 18 donor dura eyes, and 6 out of 23 donor pericardium eyes. Conclusion: No material was more prone to melting than another. Donor sclera may be slightly more cost-efficient, but gamma-irradiated pericardium has sterility advantages.