Open-angle glaucoma vs Closed-angle glaucoma

Open-angle glaucoma vs Closed-angle glaucoma

Glaucoma is a group of eye conditions that damage the optic nerve, often leading to vision loss and blindness if left untreated. Among the various types of glaucoma eye disease, open-angle glaucoma and closed-angle glaucoma are two significant categories with distinct characteristics. This blog aims to shed light on the differences between these two forms of glaucoma, emphasising the importance of early detection and treatment.

Open-Angle Glaucoma

Open-angle glaucoma is the most common type, accounting for about 90% of all glaucoma cases. It develops gradually and is often referred to as the "silent thief of sight" because symptoms are not noticeable until the advanced stages. In open-angle glaucoma, the drainage angle of the eye remains open, but the trabecular meshwork, responsible for draining the aqueous humor (fluid in the eye), becomes less efficient over time.

Risk factors for primary open-angle glaucoma include age, family history, race (more prevalent in African Americans), and certain medical conditions such as diabetes. Regular eye exams are crucial for early detection, as increased intraocular pressure can be managed effectively if identified in the early stages. Treatment may involve prescription eye drops, laser therapy, or surgery to improve fluid drainage.

Closed-Angle Glaucoma

Closed-angle glaucoma, also known as angle-closure glaucoma or narrow-angle glaucoma, is less common but considered a medical emergency. Unlike open-angle glaucoma, closed-angle glaucoma is characterised by a sudden and severe increase in normal intraocular pressure due to a blockage of the drainage angle. This blockage can occur when the iris, the coloured part of the eye, is positioned too close to the drainage angle.

Symptoms of closed-angle glaucoma may include intense eye pain, headache, nausea, vomiting, blurred vision, and the appearance of halos around lights. These symptoms necessitate immediate medical attention to prevent irreversible vision damage. Treatment typically involves medications to reduce intraocular pressure and laser or surgical procedures to create a new drainage opening.

Distinguishing Factors

Onset and Progression:
  • Open-angle glaucoma progresses slowly and is often asymptomatic until advanced stages.
  • Closed-angle glaucoma has a sudden onset, with symptoms appearing rapidly and severely.
  • Open-angle glaucoma is usually asymptomatic until vision loss occurs.
  • Closed-angle glaucoma presents with acute symptoms such as severe eye pain, headache, and nausea.
Risk Factors:
  • Open-angle glaucoma is associated with age, family history, and certain medical conditions.
  • Closed-angle glaucoma may be linked to anatomical factors, hyperopia (farsightedness), and age.

While both conditions may be different, it is imperative to treat them at the earliest. While there is no guaranteed cure for glaucoma, the right course of treatment can help slow the damage.

Understanding the distinctions between primary open-angle glaucoma and closed-angle glaucoma is crucial for both healthcare professionals and individuals at risk. Regular eye examinations by a trusted professional like Dr Nandita Rane, awareness of risk factors, and prompt medical attention in case of symptoms can contribute to early detection and effective management of these sight-threatening conditions. As research and technology advance, ongoing efforts to raise awareness and improve treatment options remain essential in the fight against glaucoma.