The use of trypan blue to distinguish Pseudo-Seidel sign from lacrimal ductule versus glaucoma drainage device leakage

Intraocular injection of trypan blue dye was effective in identifying glaucoma drainage device leakage from tube exposure, and specifically allowing clear differentiation from physiologic lacrimal gland flow. This novel technique successfully differentiated a leaking conjunctival fistula requiring treatment from a benign physiologic finding, in a case where topical fluorescein testing was not sufficient.