Glaucomas

Glaucomas are a group of eye conditions characterized by optic neuropathy and progressive visual field loss, often associated with elevated intraocular pressure (IOP) but not always. The damage involves retinal ganglion cells and their axons, leading to characteristic cupping of the optic disc and, if untreated, irreversible vision loss.

The most common forms are primary open-angle glaucoma, primary angle-closure glaucoma, normal tension glaucoma, and secondary glaucomas. Primary open-angle glaucoma is typically chronic and develops slowly with peripheral vision loss. Angle-closure glaucoma can be acute or chronic; the acute form is a medical emergency with eye pain, halos around lights, headache, nausea, and a red eye. Normal tension glaucoma occurs despite normal or only mildly elevated IOP. Secondary glaucomas arise from other conditions such as steroid use, eye trauma, inflammation, or neovascularization.

Diagnosis relies on measuring IOP with tonometry, examining the optic nerve head, and testing the visual field. Optical coherence tomography and other imaging may help assess nerve and retinal structure. Risk factors include age, family history, ethnicity (higher risk in people of African descent), high IOP, myopia or hyperopia, and certain medical conditions.

Treatment aims to lower IOP to slow or halt progression. It typically begins with medications, most often eye drops, including prostaglandin analogs, beta-blockers, alpha agonists, and carbonic anhydrase inhibitors. Laser therapies (such as trabeculoplasty or iridotomy) and surgical options (trabeculectomy, glaucoma drainage devices) may be used when medications are insufficient or not tolerated. Adherence to treatment and regular monitoring are essential, as glaucoma is often asymptomatic until advanced stages. Glaucoma remains a leading cause of irreversible blindness worldwide, making early detection crucial.