Ab-externo Angle Surgery

A well-performed angle surgery can not only save the child’s vision from glaucoma but also mitigate the risks inherent to more invasive filtering procedures that might be necessary if the initial angle surgery is unsuccessful. Trabeculotomy is the procedure of choice for managing primary congenital glaucoma (PCG) and some cases of secondary glaucoma when corneal haze impedes proper angle visualization. Trabeculotomy has a relatively steep learning curve, with success rates improving as surgeons gain experience in both the surgical technique and the choice of surgery. Adopting a reproducible technique that ensures proper identification of Schlemm's canal and minimizes the risk of deviating from it throughout the passage of the trabeculotome, suture, or microcatheter and allows for timely identification of false passages, thereby optimizing outcomes. Currently, circumferential trabeculotomy is gaining more popularity due to its higher success rate and greater intraocular pressure reduction compared to the conventional technique. This chapter will cover the indications, techniques, and outcomes of conventional, rigid-probe trabeculotomy, circumferential trabeculotomy, and combined procedures with trabeculotomy in childhood glaucoma.