eye disorders
Glaucoma
Types of glaucoma
There are many forms of adult and childhood glaucomas. Most glaucomas fall into two categories: Open-angle glaucoma Closed-angle glaucoma (angle-closure glaucoma) is more common than closed-angle glaucoma. In open-angle glaucoma, the drainage canals in the eyes gradually become clogged with tiny, microscopic deposits over months or years. This type of glaucoma is "open" because the canals are not visibly blocked (when examined under magnification, as with a Slit-Lamp Examination ), but drainage through them is still inadequate. Pressure in the eye rises slowly because fluid is produced at a normal rate but drains sluggishly. Closed-angle glaucomais less common than open-angle glaucoma. In closed-angle glaucoma, the drainage canals in the eyes become blocked or covered because the angle between the iris and cornea is too narrow. This type of glaucoma is "closed" because the canals are visibly blocked. The blockage can occur suddenly (called acute closed-angle glaucoma) or slowly (called chronic closed-angle glaucoma). If the blockage occurs suddenly, pressure in the eye rises rapidly. If the blockage occurs slowly, the pressure in the eye rises slowly as in open-angle glaucoma. 