Which type of glaucoma is characterized by stiff, closed drainage systems causing pain?

Closed-angle glaucoma, correctly identified as the right answer, is characterized by a sudden increase in intraocular pressure due to the angle between the iris and cornea becoming narrow or completely closed. In this type of glaucoma, the drainage systems for aqueous humor become obstructed, leading to a painful condition. The buildup of fluid increases pressure in the eye, which can not only lead to severe pain but also risk for vision loss if not treated promptly.

This type contrasts with open-angle glaucoma, where the drainage system is open but may be blocked over time, leading to gradual pressure increase without immediate symptoms. Normal-tension glaucoma and low-tension glaucoma are variations of open-angle glaucoma where pressure levels remain within normal ranges, yet optic nerve damage occurs. These conditions typically do not present with the acute pain associated with closed-angle glaucoma. Understanding the pathophysiology and symptoms of these different types of glaucoma is crucial for timely diagnosis and effective management.