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What is Ex-Press glaucoma shunt is made up of: and explain in detail?
Ans. (d) Stainless steelRef: Khurana 6/e, p. 256; Shield's 6/e, p. 528 The Ex-Press implant--This biocompatible device is almost 3 mm long with an external diameter of approximately 400 microns. It is a non-valved, MRI compatible, stainless steel device with a 50 micron lumen. It has an external disc at one end and a spur-like extension on the other to prevent extrusion. This implant is not put under the conjunctiva but it is implanted under the scleral flap. This has totally avoided the complication of extrusion and hypotony.