Screening for primary open-angle glaucoma in the developed world: are we there yet?

Abstract

Background: In 1995, the Quebec Agency for Health Services and Technology Assessment (AETMIS) stated that a formal screening program for primary open-angle glaucoma (POAG) could not be recommended for the province of Quebec, owing to “a high degree of uncertainty and because of the high cost such a program would entail.” The purpose of this article was to evaluate the possibility of instituting a POAG screening program in light of recent advances in the diagnosis and treatment of glaucoma. Methods: We reviewed new developments that have occurred since the mid to late 1990s in the field of glaucoma. Changes that could positively influence the feasibility and organization of future glaucoma screening programs were identified. Results: New technologies, including confocal scanning laser ophthalmoscopy (HRT II), optical coherence tomography (Stratus OCT), and scanning laser polarimetry with variable corneal compensation (GDx-VCC), permit early detection of optic nerve and nerve fibre layer structural damage. Together with advanced psychophysical tests (frequency doubling perimetry and short wavelength automated perimetry) for earlier detection of functional damage, they provide an increased understanding of the diagnosis and monitoring of POAG. Elevated intraocular pressure (IOP) remains the most important risk factor for glaucoma. Clinical trials indicate that lowering IOP at different stages of the disease can arrest or decrease its rate of progression. Moreover, it is important to assess pachymetry because IOP measurements are influenced by central corneal thickness. Finally, new treatments, such as prostaglandin analogues or selective laser trabeculoplasty, are safer and may also achieve lower intraocular pressures. Interpretation: Health policy involves the investment of public resources, and cost-effectiveness analyses for POAG screening are heavily weighted by the degree of uncertainty that glaucoma screening can be effectively and reliably achieved. The many new developments and advancements outlined herein, combined with the possible increasing prevalence of POAG, necessitate the re-evaluation of screening for primary open-angle glaucoma.