Angle-closure glaucoma is a type of eye condition that occurs when the drainage angle of the eye becomes blocked. This blockage prevents fluid from leaving the eye, leading to a rapid increase in intraocular pressure. Symptoms may include severe eye pain, headache, nausea, and blurred vision. If left untreated, angle-closure glaucoma can cause permanent vision loss. It is considered a medical emergency, and immediate treatment is necessary. Treatment options may include medications to lower eye pressure or surgical procedures to create a new drainage pathway for the fluid.