Confirming and establishing patency of glaucoma drainage devices using trypan blue.

The use of trypan blue is increasing in complicated cataract, retina, and glaucoma surgeries. We report on the use of trypan blue to help visualize the capsule over a glaucoma drainage implant and to assess adequate flow in different situations involving both valved and nonvalved implants. These cases demonstrate 3 key points. One, when completing the second stage of a tube, it is essential to prime the tube to ensure adequate flow. Two, when extensive conjunctival scarring is present, trypan blue can be used to stain the capsule around the plate and confirm adequate flow. Three, if one is concerned of the functionality of a valved glaucoma implant, trypan blue can be used to both confirm and reestablish functionality of the valve mechanism.