Endoscopic Cyclophotocoagulation as a Minimally Invasive Glaucoma Surgery in Clinical Practice: Appropriate for All Stages?

Endoscopic cyclophotocoagulation (ECP), originally developed for the treatment of refractory glaucoma, has seen expanding use in recent years as a minimally invasive glaucoma surgery (MIGS), particularly when combined with cataract extraction. ECP reduces intraocular pressure (IOP) by suppressing aqueous humor production through targeted ablation of the ciliary processes under endoscopic guidance. This contrasts fundamentally with outflow-enhancing MIGS, which aim to restore impaired physiological function. Theoretical modeling suggests that reductions in aqueous production following ECP may approximate changes that occur over several decades of natural aging. While ECP spares the conjunctiva and is repeatable, its irreversible suppression of aqueous production may raise long-term physiological concerns. Given that aqueous humor supports the metabolic environment of anterior segment structures, sustained suppression may impact ocular homeostasis. Although clinically noteworthy complications remain rare, the growing use of ECP in non-refractory cases necessitates careful consideration. Especially as green-laser ECP is newly introduced in Japan and primarily used for refractory glaucoma, I believe it is important to revisit the fundamental differences between outflow- and inflow-targeting procedures and evaluate the broader implications of routine ECP application across glaucoma stages.