Materials for glaucoma drainage device

Abstract

Implantation of glaucoma drainage device (GDD) is a common technique for glaucoma treatment to lower intraocular pressure (IOP). It provides an alternate pathway for drainage of aqueous humour out of the anterior chamber. To overcome the problem of early postoperative hypotony, a valve can be included to limit aqueous flow. However as wound healing takes place over a period of approximately 6 weeks, fibrous encapsulation of the end plate occurs. This will exert pressure on the plate, reducing aqueous flow through the GDD resulting in an increase in IOP to abnormally high levels. This condition is known as ocular hypertension.

To avoid ocular hypertension in valved GDD, this report proposed to develop a biodegradable valve that is able to disintegrate after 6 weeks. The influence of electron beam (e-beam) irradiation on the in-vitro hydrolytic degradation behaviour of poly(DL-lactide-co-ε-caprolactone) (PDLLC) 70/30, and the pressure-flow characteristic of valve fabricated from PDLLC films were investigated. Solvent-casted PDLLC films were irradiated at 10, 20 and 40 Mrad and immersed in phosphate buffer saline (PBS) solution incubated at 37 oC for a period of 6 weeks.