What is zonules in the eye?
The zonules are the tiny thread-like fibers that hold the eye’s lens firmly in place. The zonules also work with the ciliary muscles to help the lens accommodate (change focus). The zonule fibers tighten and pull the lens for near vision.
What is zonular instability?
Zonular instability is no doubt the bane of many a cataract surgeon, as the risk for the cataract moving posteriorly or the vitreous moving anteriorly becomes higher, putting patients at risk for such complications as a retinal hole or detachment.
What is zonular weakness?
Zonular weakness can be caused by disease or trauma, and its presence can make cataract surgery more challenging. Fortunately, there are adjunctive devices to effectively manage it and achieve successful outcomes. Causes. Certain diseases of the eye are associated with zonular weakness or insufficiency.
What do zonules do?
Ciliary zonules are a ring of fibrous structures anchoring the ciliary body with the lens of the eye. These are the structures that help to maintain the position of the lens in the optical path, and anchor muscles that change the shape of the lens to alter focus.
What is Zonular cataract?
This type of cataract is bilateral. It can be congenital or it can be acquired during the first years of life due to tetany or rickets. The cataract is always large enough to occlude the pupil. Its effect on vision depends primarily on the density of its components – especially the nucleus.
What is a lamellar cataract?
Lamellar or zonular cataract is a hereditary cataract that is transmitted in an autosomal dominant mode. The crystalline opacities are located at the level of the primary fibers in the embryonic nucleus. This cataract is usually bilateral and asymmetrical.
What is lamella cataract?
What is a sunflower cataract?
Sunflower cataract (SC) is considered a second ophthalmic sign of WD and has been called pathognomonic for WD [8–14]. SC consists of a thin, centralized opacification that is located directly under the anterior capsule and encompasses between one-third and one-half of the anterior lens pole surface area.
What is the zonule of the eye?
[zōn´ūl] a small zone. ciliary zonule(zonule of Zinn) a series of fibers connecting the ciliary body and lens of the eye, holding the lens in place. Ciliary zonule.
What does it mean when the lens zonules are weak?
According to the pamphlet, “The abnormal protein seen in this condition settles and weakens the lens zonules, which are suspensory fibers that hold the lens in place. The ciliary body has three functions: accommodation, aqueous humor production and maintenance of the lens zonules.
What is the function of the ciliary zonule?
ciliary zonule (zonule of Zinn) a series of fibers connecting the ciliary body and lens of the eye, holding the lens in place.
What is the zonule of Zinn?
ciliary zonule (zonule of Zinn) a series of fibers connecting the ciliary body and lens of the eye, holding the lens in place. Ciliary zonule.