A Novel Technique of a Transcorneal Suture to Manage an Iris Tuck into the Tube of a Glaucoma Drainage Device.

Abstract

Glaucoma drainage devices create an alternative pathway of aqueous drainage from the anterior chamber by channelling aqueous out of the eye through a tube to a subconjunctival bleb or the suprachoroidal space. They may be associated with a number of potential complications including tube malpositioning. This malpositioning may have serious sequelae such as corneal endothelial damage, chronic iritis, tube iris touch, cataract formation, or tube occlusion. Occlusion of the mouth of the tube by the iris impedes aqueous drainage and results in the failure of intraocular pressure (IOP) control. Tube repositioning in cases of occlusion of the mouth of the tube by the iris often involves extensive and potentially complicated surgery requiring tube removal and reinsertion. We describe a new minimally invasive surgical technique for correcting posterior tube malposition resulting in tube occlusion by the iris. The iris had occluded the tube of a Baerveldt prototype glaucoma drainage devices and caused an intractable increased IOP. After our tube sling suture, the tube was free, and the IOP normalized. The procedure entailed no difficult dissection or major surgical intervention. The technique is illustrated by a surgical video. This novel technique is a simple method that relieved the occlusion successfully, and avoided the need to redissect the conjunctiva or shorten the tube.