A systematic review of ionizing radiation-induced glaucoma: clinical manifestations, pathogenesis, and current...

Ionizing radiation-induced glaucoma (IRG) is an uncommon yet vision-threatening complication that presents primarily as neovascular glaucoma (NVG) after high-dose exposure and normal-tension glaucoma (NTG) after low-dose exposure. Despite increasing recognition, its dose-response relationship, mechanisms, and optimal management remain poorly defined. This review evaluates the clinical spectrum, pathogenesis, and therapeutic approaches of IRG to inform future research and practice.

A systematic literature search of PubMed/MEDLINE, Embase, Scopus, and the Cochrane Database (1964-2024) was conducted following PRISMA guidelines. Among 7256 screened articles, 37 studies fulfilled the inclusion criteria.

NVG typically develops following ocular radiotherapy exceeding 30 Gy, particularly in patients with uveal melanoma, and is characterized by retinal ischemia, neovascularization, and secondary intraocular pressure elevation. NTG arises from chronic low-dose exposure (< 1 Gy), producing optic nerve injury and visual field loss without elevated pressure. Anti-VEGF therapy can temporarily control NVG progression, whereas trabeculectomy, glaucoma drainage devices, and cyclodestructive procedures are variably employed but often limited by postoperative complications and inconsistent outcomes. The lack of consensus-driven protocols and heterogeneity across studies underscore ongoing clinical challenges.

IRG represents a dose-dependent entity with distinct phenotypes and mechanisms. Current therapies provide partial benefit but remain unsatisfactory in terms of durability and standardization. Advancing the field will require mechanistic studies to clarify radiation-induced optic neuropathy and vascular injury, alongside well-designed trials to establish preventive strategies and evidence-based treatment algorithms.