Viscodilation of Schlemm's Canal Combined with Goniectomy Using a 30 G Needle (Visco-Bent Ab Interno Needle Goniectomy).

Background and aim: Bent ab interno needle goniectomy (BANG) is a low-cost minimally invasive glaucoma surgery (MIGS) technique that has gained wide popularity in developing nations. However, the risk of injury to surrounding angle structures and especially the outer wall of Schlemm's canal (SC) is the main drawback of this technique. We describe a simple and easy-to-perform modification, "Visco-BANG," to improve the safety and efficacy of the BANG procedure. Technique: A 30 gauge (G) needle attached to a syringe filled with cohesive viscoelastic is used. The needle is bent at the proximal junction of the bevel with bevel towards the operating surgeon. The needle is then inserted into the SC and viscoelastic injected to dilate the canal, creating a buffer between the inner and outer walls of SC, which is followed by cutting of a trabecular meshwork (TM) strip. Conclusion: The current modification can prevent damage to adjoining angle structures, including the outer wall of SC, which is critical for aqueous outflow. It can potentially increase efficacy of the BANG procedure by incorporating viscodilation of the SC along with removal of the TM. Clinical significance: Injury to surrounding structures causes a fibrotic response, which is the main cause of failure for the BANG procedure. Prevention of injury to adjoining structures and dilatation of the SC can potentially increase the long-term success rates of this procedure. How to cite this article: Dada T, Beri N, Sethi A,