trabeculoplasty

Trabeculoplasty is a laser procedure used to treat glaucoma by enhancing drainage of aqueous humor through the trabecular meshwork, thereby lowering intraocular pressure (IOP). It is typically indicated for open-angle glaucoma or ocular hypertension when laser therapy is appropriate and when medications alone are insufficient or undesirable.

Two main forms are Argon Laser Trabeculoplasty (ALT) and Selective Laser Trabeculoplasty (SLT). ALT uses thermal energy to create burns in the trabecular meshwork; SLT uses low-energy pulses that selectively target pigmented trabecular meshwork cells with less collateral damage. SLT is generally favored for repeatability and safety, while ALT may be preferred in heavily pigmented angles.

The procedure is performed on an outpatient basis under local or topical anesthesia. A gonioscopy lens is placed on the eye to visualize the angle, and the laser is directed at the trabecular meshwork to alter its function. The session lasts several minutes per eye, and postoperative care may include anti-inflammatory eye drops.

In terms of outcomes, many patients experience a modest to moderate reduction in IOP, commonly around 20–30%, which can last months to years. The effect can be reduced by prior laser scarring and iris or angle anatomy. Both ALT and SLT may be repeated if IOP rises again, though repeat effectiveness varies. It is not a cure, and ongoing monitoring and sometimes additional treatment remain necessary.

Potential risks include transient IOP spikes, inflammation, discomfort, minor bleeding in the anterior chamber (hyphema), and, rarely, damage to the cornea or vision. It is not effective for angle-closure glaucoma and is generally avoided in eyes with active inflammation or neovascularization.