Corpus ciliary
The ciliary body or the ciliary body (also ciliary body called) is a section of the middle eye skin . It is used to suspend the lens and for accommodation . It is also involved in the production of aqueous humor .
The transition from the choroid to the radiating body is the ora serrata (sawn edge). From here, the ciliary body bulges in the form of an annular bulge (ciliary ring, orbiculus ciliaris or pars plana ) inwards towards the lens. At the apex of the bulge, ciliary processes ( ciliary processes ) protrude inward. Their entirety represents the ciliary wreath ( Corona ciliaris ). Zonular fibers ( Fibrae zonulares ) originate from these processes and attach to the lens equator. The totality of the zonular fibers is called the zonula ciliaris . It goes forward into the iris .
The radiation body consists of pigmented connective tissue . It is covered by a two-layer epithelium, the pars ciliaris retinae , which is part of the pars caeca retinae (the “blind” part ( pars caeca ) of the retina ). The fenestrated radiator capillaries together with the unpigmented cells of this epithelium form the aqueous humor and hyaluronic acid .
In the intrinsic layer of the ciliary body is smooth muscle ciliary (ciliary muscle) stored. The contraction of this parasympathetically innervated ciliary muscle causes near accommodation. It narrows the inner circumference of the radiating body, which relaxes the zonular fibers. Due to the inherent elasticity of the lens, it rounds off and reduces its radius of curvature, which leads to close-up focus. When the muscle slackens, the zonular fibers are tightened again and pull the lens back into a flattened shape (remote setting) against its inherent elasticity. The ciliary muscle is innervated by the oculomotor nerve (3rd cranial nerve ). The switching of the parasympathetic fibers takes place in the ciliary ganglion . The corpus ciliare is sensitively innervated by the Nervi ciliares longi et breves .
Clinical references
- If the zonular fibers tear off, the lens will shift ( lens luxation ).
- Painful ciliary spasm can result from inflammation of the anterior structures of the eye .
See also
literature
- Theodor Axenfeld (founder), Hans Pau (ed.): Textbook and atlas of ophthalmology. With the collaboration of Rudolf Sachsenweger and others 12th, completely revised edition. Gustav Fischer, Stuttgart et al. 1980, ISBN 3-437-00255-4 .