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The ciliary body is a ring of muscle and tissue inside your eye that you cannot see from the outside. It sits just behind the iris, which is the colored part of your eye. This small structure does very important work to help your eye focus and stay healthy.
read more about the ciliary body ...The ciliary body has two main jobs. First, it changes the shape of the lens, which allows your eye to focus on objects at different distances. Second, it produces a clear liquid called aqueous humor. This fluid fills the front of your eye, maintains eye pressure, and gives the eye nutrients.
When you look at something up close, the ciliary muscle tightens. This action makes the lens inside your eye become thicker and more curved, which helps you see the nearby object clearly. When you look at something far away, the muscle relaxes, and the lens becomes flatter.
Several conditions can involve the ciliary body. In glaucoma, the balance of fluid being made and drained is off, leading to high eye pressure. Some glaucoma medicines work by telling the ciliary body to make less fluid. It can also become inflamed, a condition called uveitis, which causes pain and blurry vision.
The ciliary body is the engine behind your eye's ability to "autofocus," a process called accommodation. The muscle is attached to the lens by tiny fibers called zonules.
When the ciliary muscle contracts, it releases tension on these fibers, allowing the flexible lens to spring into a rounder, thicker shape for close-up reading. When the muscle relaxes, the fibers pull tight, flattening the lens for distance vision.
Beyond focusing, the ciliary body acts as the eye's faucet. The ciliary processes (finger-like projections) constantly secrete aqueous humor. This fluid flows from the ciliary body, around the iris, and into the front chamber of the eye before draining out. This continuous flow delivers essential oxygen and glucose to the lens and cornea, which do not have their own blood supply.
No, you cannot feel the ciliary muscle moving as it focuses your vision. If you read for a long time and feel eye strain, it is a sign that the muscle is tired, but you do not feel the movement itself.
Yes. As you get older, the lens in your eye gets stiffer. The ciliary muscle has a harder time changing the lens's shape, which is why most people need reading glasses after age 40. This condition is called presbyopia.
The ciliary body makes the fluid that maintains eye pressure. If too much fluid is made or it doesn't drain right, pressure builds up. High eye pressure can damage the optic nerve and cause glaucoma.
You should see an eye doctor if you have trouble focusing your vision, eye pain, or sudden sensitivity to light. Regular eye exams are also important because a doctor can check your eye pressure and look for signs of problems like glaucoma before you notice any symptoms.
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