Gest, Thomas R; Burkel, William E. "Anatomy Tables - Eye." Medical Gross Anatomy. Source location: Random House, Inc. Reference.com. The ciliary body along with the iris and the choroid, are pigmented tissues that form the uveal tract of the eye. One of the functions of the ciliary body is to produce aqueous humor, the fluid that fills the anterior and posterior chambers.
When near objects are viewed, the ciliary muscle contracts, the ligaments relax, and the lens, being elastic,…
Retrieved on 2010-01-16 from The ciliary muscle is an unstriped, involuntary, muscle concerned with alterations in the adjustments of focus—accommodation—of the optical system; the fibres run both across the muscle ring and circularly, and the effect of their contraction is to cause the whole body to move forward and to…
Lee Ann Remington OD, MS, FAAO, in Clinical Anatomy and Physiology of the Visual System (Third Edition), 2012. Le, Tao T.; Cai, Xumei; Waples-Trefil, Flora. University of Michigan Medical School. Retrieved on 2010-01-16 from Dictionary.com, "-ary", in The American Heritage Dictionary of the English Language, Fourth Edition.
Ciliaris muscle, muscle of the ciliary body of the eye, between the sclera (white of the eye) and the fine ligaments that suspend the lens. The ciliary muscle is part of the ciliary body. The ciliary muscle is composed of smooth muscle fibers oriented in longitudinal, radial, and circular directions.
The stroma of the ciliary body is largely occupied by the ciliary muscle. The ciliary muscle is a ring of smooth muscle [3] [4] in the eye's middle layer (vascular layer) that controls accommodation for viewing objects at varying distances and regulates the flow of aqueous humor into Schlemm's canal.It changes the shape of the lens within the eye, not the size of the pupil [5] which is carried out by the sphincter pupillae muscle and dilator pupillae. Each of these muscle systems contracts as a perceived object approaches. (2012).
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See more. Source location: Random House, Inc. Reference.com. While the main function of the ciliary muscle is related to accommodation, it is also critically involved in both conventional trabecular and unconventional uveoscleral aqueous humor outflow. …two eye-muscle systems called the ciliary muscles and the rectus muscles.
Interweaving occurs between fiber bundles and from layer to layer, such that various amounts of connective tissue are found among the muscle bundles. Ciliary Muscle. The main function of the ciliary muscles is to change the shape of the lens in the eye to help with focusing.
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(Uveitis refers to inflammation of these structures.) Source location: Houghton Mifflin Company, 2004. Anatomy & Embryology of the Eye" (Chapter). History at your fingertips January 5, 2010 Schachar, Ronald A. The ciliary muscle receives parasympathetic fibers from the Presynaptic parasympathetic signals that originate in the The parasympathetic tone is dominant when a higher degree of accommodation of the lens is required, such as reading a book.Contraction and relaxation of the longitudinal fibers, which insert into the The arteries of the choroid and iris. "Anatomy and Physiology."
Reference.com. The effect of… 13 January 2010 "cilia", Unabridged. 2006–2010. Ciliary muscle definition, the smooth muscle in the ciliary body, the action of which affects the accommodation of the eye. 2000. The greater part of the sclera has been removed.
… is set at infinity, the ciliary muscle relaxes, the muscle’s inside diameter is increased, more pull is exerted on the lens by the ligaments, and the front surface of the lens is flattened. It is composed of both longitudinal and circular fibres and serves to change the shape of the lens, enabling the eye to focus upon near or distant Retrieved on 2010-01-16 from "ciliary," in Dictionary.com Unabridged. (Chapter 4) Riordan-Eva Paul, "Chapter 1. The ciliary fibers have circular (Ivanoff), longitudinal (meridional) and radial orientations.
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The ciliary effect is called accommodation (focusing the lens for near or far vision), and the rectus effect is called convergence (moving the entire eyeball).
MedIQ Learning, LLC. The ciliary body has three functions: accommodation, aqueous humor production and resorption, and maintenance of the lens zonules for the purpose of anchoring the lens in place. Our editors will review what you’ve submitted and determine whether to revise the article.