Laser Radiation for Modulation of Trabecular Outflow in Comprehensive Glaucoma Management

Objectives: to analyze the evolution, mechanisms of action, clinical efficacy, and safety of laser-based modulation of trabecular outflow in the comprehensive management of glaucoma, and to evaluate current and emerging laser technologies aimed at improving intraocular pressure control.

Methods. A structured analysis of experimental and clinical studies describing laser techniques for trabecular modulation was performed. The review included argon laser trabeculoplasty, selective laser trabeculoplasty, Nd:YAG-based hydrodynamic activation methods, excimer laser trabeculostomy, and infrared laser approaches. Data on the action mechanisms, treatment parameters, intraocular pressure reduction, durability of effect, complication profile, and impact on medication burden were assessed based exclusively on the presented material.

Results. Argon laser trabeculoplasty demonstrated a mean intraocular pressure reduction of approximately 30 %, but its long-term efficacy declined over time and was associated with postoperative pressure spikes and structural alterations. Selective laser trabeculoplasty provided a 21.8–29.4 % reduction within six months, with a favorable safety profile and reduced tissue damage; however, the median duration of effect was approximately two years. Nd:YAG-based activation techniques showed significant intraocular pressure reduction and decreased medication burden, though repeat procedures were required in a subset of patients. Excimer laser trabeculostomy achieved sustained pressure reduction with a stable long-term effect and minimal thermal injury, supporting its role within minimally invasive glaucoma surgery. Infrared laser systems, particularly those targeting wavelengths with high water absorption, demonstrated promising experimental precision but were limited by technical delivery constraints.

Conclusion. Laser modulation of trabecular outflow represents an effective and relatively safe strategy for intraocular pressure reduction in primary open-angle glaucoma. Despite proven clinical benefit, durability of effect remains a limitation for several techniques. Further refinement of laser parameters and development of optimized delivery systems are essential to enhance long-term outcomes in glaucoma surgery.

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