Trabeculoplasty is a laser treatment for glaucoma. It is done on an argon laser equipped slit lamp, using a Goldmann gonioscope lens mirror. Specifically, argon laser is used to improve drainage through the eye's trabecular meshwork, from which the aqueous humour drains. This helps reduce intraocular pressure caused by open-angle glaucoma.
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Trabeculoplasty Wikipedia(Text) CC BY-SA