Design and performance of a large lumen glaucoma drainage device.

PurposeWe report the in vivo testing of a large-lumen glaucoma drainage (LL-GDD) device equipped with a flow regulator. The device's membrane can be non-invasively opened with laser in the postoperative period to adjust aqueous flow and intraocular pressure.MethodsThe initial LL-GDD prototypes were constructed using 22 G silicone angiocatheters cut down to size. A 10 nm PVDF membrane was then affixed to the end using cyanoacrylate. The LL-GDD was tested first in a model eye equipped with ports for infusion and pressure measurement and in New Zealand rabbits.ResultsNew Zealand white satin cross rabbits were used, two eyes receiving the LL-GDD and the two fellow eyes serving as the control group with no intervention performed. After the procedure, the IOP in the LL-GGD surgical group dropped an average of 5.5 mm Hg (P=0.001), which was maintained until the membrane laser procedure at week 5 resulting in an average IOP reduction of 1.8 mm Hg. At week 7, the average IOP in the surgical group was 11 mm Hg compared with 18 mm Hg in the control group (P<0.001). A second laser procedure was done to completely open the membrane face, which resulted in an immediate drop in the average IOP of the surgical group by another 2.7 mm Hg, which was maintained until the study termination at day 55.ConclusionsThe large-lumen glaucoma drainage device demonstrated an ability both to prevent immediate postoperative hypotony and to allow progressively lower IOP on demand in this proof-of-concept study.