A: The USDA created the Plant Hardiness Zone Map to help gardeners select plants that will survive in their particular climate zone. The zones are based on the average annual lowest winter temperature in a location, and each numeric zone spans 10 degrees (F) and is further divided into 5-degree âaâ and âbâ sections.
Secondary Glaucoma. Secondary glaucoma is often a side effect of injury or another eye condition, such as cataract or eye tumors. Medicines, such as corticosteroids, may also cause this type of glaucoma. Rarely, eye surgery can cause secondary glaucoma.laucoma is not a singular eye disease, but is instead a term for several eye conditions that can damage your optic nerve. The optic nerve is the nerve that supplies visual information to your brain from your eyes. Glaucoma is usually (but not always) the result of abnormally high pressure inside the eye.
SHARE IT. a a a. Glaucoma is an eye disorder that causes damage to the optic nerve and can lead to vision loss. According to the American Optometric Association, in the United States, glaucoma is the second leading cause of blindness and is estimated to affect about 3 million Americans.aving certain structural defects within the eye is considered a possible cause of glaucoma. For example, some people have a narrow angle between the iris and the cornea, which can interfere with fluid drainage. Pressure in the eye can increase and cause damage leading to glaucoma.