[Trabeculotomy, deep sclerectomy and viscocanalostomy. Non-fistulating microsurgical glaucoma operation ab externo]

Filtering procedures have been the gold standard in glaucoma surgery for more than 30 years. Trabeculotomy, deep sclerectomy, and viscocanalostomy might become the procedures of first choice in the future. These new, non-penetrating procedures have not yet been compared to filtering procedures in prospective randomized studies with long-term follow-up. In addition, it is not really known how they modify outflow of the aqueous humor. The surgical technique is described and the most likely underlying effects are discussed.