[Postoperative Follow-Up of Glaucoma Drainage Devices]

There is an increasing trend towards using glaucoma drainage implants. The postoperative management of such devices depends on their technical characteristics and specific complications. The Baerveldt glaucoma implant with its larger surface area has been shown to lower mean intraocular pressure more effectively than the Ahmed-FP7 implant. As a non-valve implant, however, it has been associated with a higher rate of severe complications, particularly ocular hypotension. Moreover, glaucoma implants may induce diplopia if they interfere with extraocular muscles. Topical treatment with antibiotics and steroids is necessary in cases of intraocular inflammation. In refractory cases, the tube may even have to be removed. Surgical reposition of the tube may be indicated when it is severely dislocated. Increased intraocular pressure is primarily treated by pressure-lowering medications during postoperative follow-up. If topical glaucoma medication is insufficient to control increases in intraocular pressure due to encapsulation, a second implant may be considered or the capsule surrounding the implant may be excised to reduce outflow resistance or additional cyclodestructive procedures can be performed. Chronic hypotension may be treated with tube ligation or occlusion. Severe corneal oedema may require lamellar keratoplasty. Conjunctival erosions with tube exposure or tube retractions also require surgical correction.