[Coloring the floor of Schlemm's canal in deep sclerectomy]

Increased intraocular pressure in glaucoma, resistant to maximal tolerated medical therapy, can be relieved by deep sclerectomy. Its advantage over classical trabeculotomy is fewer postoperative complications. This probably results from its being relatively noninvasive, since the anterior chamber is not penetrated. Successful deep sclerectomy requires preservation of the trabeculo-descemetic membrane, which forms part of the floor of Schlemm's canal. Aqueous flows from the anterior chamber across the trabeculo-descemetic membrane and into the ocular venous drainage. Despite the importance of its preservation, during deep sclerectomy it is perforated in 10-15% of cases. Coloring the endothelium lining the floor of the canal with gentian violet solution improves visualization of the membrane and thus aids in its preservation. Its use makes the procedure easier and should improve results.