Anatomy Of The Eye Flashcards
The peripheral organ of vision, is situated in a skeletal cavity, the orbit. 1inch in diameter and 8 grams in weight. Emebede in the orbital fat, separated from it by a thun fascial sheath.
The eyeball
Fascial sheath separting the eyeball from the orbital fat
Capsule of Tenon
Two cavities of the eyeball
Anterior cavity and posterior cavity
Further divided into anterior and posterior chambers due to the position of the iris
Anterior cavity
Contains the acqueous humour produced by ciliary process
Anterior cavity
Located behind the iris and contains the VITREOUS HUMOUR enclosed in hyaloid membrane
Posterior cavity
What are the layers of the eyeball?
Fibrous coat, Vascular coat, and Neural coat
Cosists of the scleraand cornea
Fibrous coat
Relatively hard consistency, is a dense layer which, when distended by intraocuoar pressure, maintains the shale of the eyeball.
Sclera
External surface is white and smooth and is in contact with the inner surface of the fascial sheath of the eyeball.
Sclera
Provides passage for nerves of the cornea and vascular autonomic nevrs and attached for extrinsic eye muscles.
Sclera
It is the anterior, projecting trasnparent part of the external tunic, and its tear film cover is the major site of REFRACTION OF LIGHT entering the eye.
Cornea
Cointains the Choroid, teh ciliary body, and the iris
Vascular coat
Is a thin, highly vascular, dark brown tissue which lines almost the posterior 5/6 of the eye.
Choroid
Pierced behind the optic nerve and is firmly adherent to the sclera.
Choroid
Thicker posteriorly, and internally it si firmly attached to the retinal pigmented layer
Choroid
Directly continuous with the choroid behind and with the iris in front. It shows a scalloped periphery where it is conituous with the choronoid and retina, termed the ORA SERRATA
Ciliary body
Concerned with the susoension of the lens and with accomodation. It is also a majot source of aqueous fluid for the anterior segment of the eye
Ciliary body
Is an adjustable diaphragm around a central aperture.
Iris
Concentration of these cells is the main factor determining the hue of the iris
Melanocytes
This is a flat annulus of smooth muscle about 0.75mm wide and 0.15mm thick. It is densely packed fusiform myocytes are often arranged in small bundles and pass circumferentially around the pupil.
Sphicnter pupillae
A thin stratum lying intermediately anterior to the epithelium of the posterior iridial surface.
Dilator pupillae
It is the neural, sensory stratum of the eyeball. Thin and thickest near the optic disc.
Retina
Photoreceptors of the retina
Rod and cone cells