Glaucoma is the most common cause of irreversible blindness globally, with an estimated 64 million persons with the disease in 2013 and a projected number of 111 million by 2040.1 Glaucoma is asymptomatic until late in the disease, with population-based studies estimating that up to 72% of individuals with glaucoma remain undiagnosed.2 Increased intraocular pressure (IOP) is a risk factor for the development of glaucoma but does not define the disease. Glaucoma is categorized as open-angle glaucoma, which affects an estimated 44 million persons globally and accounts for an estimated 69% of glaucoma cases, or as closed-angle glaucoma, which accounts for 31% of cases and affects an estimated 20 million persons.1