A procedure to treat glaucoma in which the canal of Schlemm is dilated by injection of viscoelastic.
[visco (elastic) + canal + -stomy]
A type of non-penetrating filtration surgery aimed at lowering intraocular pressure by dissecting a superficial scleral flap and excising a deeper partial-thickness scleral flap below, leaving a thin membrane consisting of trabeculum and Descemet's membrane, through which the aqueous humour diffuses. It then drains from the anterior chamber into the subconjunctival space or through Schlemm's canal into which a high-density viscoelastic substance has been injected. The superficial flap is sutured in place at the end of the procedure. Intraocular pressure reduction is not usually as large as with trabeculectomy. See filtration surgery.