Long and short of Ahmed glaucoma valve tube.

Abstract

The Ahmed Glaucoma Valve (AGV, New World Medical Inc., Rancho Cucamonga, CA, USA) is a glaucoma drainage device commonly used in the treatment of refractory glaucoma either as a primary surgical procedure or after the failure of conventional filtration procedures. During surgery, After the AGV plate is fixed to the sclera, at least 8 mm posterior to the corneoscleral limbus, the length of tube is trimmed to the desired length, based on decision to insert it in the anterior chamber (AC) or ciliary sulcus. This video describes that the length of AGV silicone tube should be cut based on decision to place it in the AC or ciliary sulcus. The tube should not be cut too long or short as in either case it may cause postoperative complications. The video illustrates useful tips for AGV tube insertion into the AC, taking care that it does not cross pupillary margin and is of adequate length. The silicone AGV tube is cut using Westcott scissors to permit a length of 2- to 3-mm tube insertion in the AC, with its bevel facing up, and the tip is cut to an angle of 30°, to facilitate AC entering. In ciliary sulcus placement of the AGV tube, the tunnel is made longer when compared with the AC implantation, and the length of tube should be kept long enough for the tip to be just visible beyond the pupillary border. This video highlights the importance of customization of the AGV tube length for individual patients based on its placement into AC or ciliary sulcus. https://youtu.be/jqS4SvCkSqs.