Laser trabeculoplasty
Argon or diode laser "burns" are applied to the trabecular meshwork. How this treatment works is uncertain. It was thought to contract one part of the meshwork, so stretching and opening up adjacent areas, but a more recent hypothesis is that it rejuvenates the cells in the trabecular meshwork. This treatment is used only in the types of glaucoma where the drainage angle is open. Its effect is relatively short term, so this treatment is mainly used for more elderly patients.
Laser iridotomy
Peripheral laser iridotomy (PI) can be performed in cases of angle closure glaucoma with the Nd-YAG laser, which (unlike argon or diode lasers) actually cuts holes in tissue rather than just burning. This procedure can be performed without incising the eye.
Laser iridoplasty
Argon laser iridoplasty is a useful procedure in some forms of angle closure glaucoma. A ring of laser burns is applied to the peripheral iris, causing contraction of tissue. This pulls the peripheral iris away from the drainage angle and helps to reduce angle occlusion.
Laser ciliary body ablation
Lasers can be used to burn the circular ciliary body that produces the aqueous humour. At the correct wavelength the laser radiation passes through the white sclera and is only absorbed by the pigmented ciliary body (transcleral ciliary body cycloablation). This treatment is now commonly performed with a diode laser and usually has to be repeated to maintain lowering of IOP. Most patients undergoing laser ciliary body ablation need to continue medical therapy. Laser destruction of the ciliary body usually is used only in advanced refractory glaucomas or where other surgical options are limited.
