Microfluidic characterization of a valved glaucoma drainage device with implications for enhanced therapeutic efficacy

In this paper, we report on the microfluidic characterization of a valved glaucoma drainage device (the Ahmed™ glaucoma valve). Using a microfluidic test set-up, we have simulated the aqueous humor flow and post implantation fibrous tissue encapsulation of the external plate. We have shown that, contrary to the prevailing belief, the valve significantly contributes to the total pressure even after the fibrous capsule formation. This was demonstrated both by disabling the valve using sharp dissection, and by bypassing it using a polyimide microtube. ANSYS™ and Fluent™ simulations verified the pressure measurements following the microtube insertion. Further reduction of intraocular pressure after fibrous capsule formation could significantly reduce the potential for glaucoma progression.