In closed-angle glaucoma, the angle closes how?

In closed-angle glaucoma, the angle closes how?

• A. Opens and closes gradually
• B. Closes suddenly and unexpectedly
• C. Stays permanently open
• D. Does not affect intraocular pressure

Answer: (B)

The key idea is that in angle-closure glaucoma the drainage angle can shut abruptly, not inch by inch. A sudden pupillary block or iris bunching causes the iris to press against the trabecular meshwork, momentarily blocking outflow. When drainage is suddenly blocked, aqueous humor backs up quickly, causing a rapid rise in intraocular pressure. This creates an acute, painful attack that is a true emergency. Think of it as an abrupt lid-closure of the drainage pathway triggered by factors like dim lighting or an anatomy with a shallow anterior chamber. That abrupt closure explains why the correct description is that the angle closes suddenly and unexpectedly. Other scenarios—gradual closure, the angle remaining open, or no impact on pressure—don’t fit the abrupt, pressure-spiking nature of this condition.

The key idea is that in angle-closure glaucoma the drainage angle can shut abruptly, not inch by inch. A sudden pupillary block or iris bunching causes the iris to press against the trabecular meshwork, momentarily blocking outflow. When drainage is suddenly blocked, aqueous humor backs up quickly, causing a rapid rise in intraocular pressure. This creates an acute, painful attack that is a true emergency. Think of it as an abrupt lid-closure of the drainage pathway triggered by factors like dim lighting or an anatomy with a shallow anterior chamber. That abrupt closure explains why the correct description is that the angle closes suddenly and unexpectedly. Other scenarios—gradual closure, the angle remaining open, or no impact on pressure—don’t fit the abrupt, pressure-spiking nature of this condition.