How does open-angle glaucoma differ from closed-angle glaucoma in terms of pain?

Open-angle glaucoma and closed-angle glaucoma represent two distinct types of glaucoma, with significant differences in their symptoms and the underlying physiological processes.

Open-angle glaucoma is often referred to as the "silent thief of sight" because it typically progresses gradually and without noticeable symptoms or pain until the later stages of the disease. Patients may not experience any discomfort as the intraocular pressure rises slowly, leading to optic nerve damage over time. The lack of pain is one of the key characteristics of open-angle glaucoma, making it crucial for individuals, especially those at higher risk, to undergo regular eye examinations.

In contrast, closed-angle glaucoma (also known as angle-closure glaucoma) can present with acute symptoms including severe eye pain, headache, nausea, and vomiting. This type occurs when the iris blocks the drainage angle of the eye, causing a rapid increase in intraocular pressure. The sudden onset of these symptoms requires prompt medical treatment to prevent irreversible vision loss.

Understanding these differences is essential for recognizing the importance of routine eye exams and the need for awareness of glaucoma risk factors in order to catch the disease before it reaches a stage where significant damage has been done.