ANATOMY OF EYE By Dr Manjula Vastrad Asst

ANATOMY OF EYE By : Dr. Manjula Vastrad Asst Prof Dept of Shareera Rachana SMVVS RKM AMC VIJAYAPURA

Introduction The eye is a specialized sense organ that helps us to understand our environment. It is a sensory unit composed of three parts: receptor, sensory pathway, and a brain center. It is spherical in shaped. It is about 2. 5 cm in diameter & situated in the orbital cavity

The eye is made up of three coats, or layers, enclosing various anatomical structures. The outermost layer, known as the fibrous tunic, is composed of the cornea and sclera , which provide shape to the eye and support the deeper structures.

The middle layer, known as the vascular tunic or uvea, consists of the choroid, cilia ry body pigmented epithelium and iris.

The innermost is the retina, which gets its oxygenation from the blood vessels of the choroid(posteri orly) as well as the retinal vessels (anteriorly).

Layers: 1. Sclera – white, outer layer of the eyeball; tough, fibrous membrane that helps to maintain the spherical shape of the eyeball 2. Cornea – part of sclerotic coat; transparent, front part of eyeball through which light waves pass , no blood vessels but lots of nerve endings

3. Choroid layer – middle layer of the eye; supplies blood vessels to the eye and contains dark pigment granules that prevent the reflection of light in the eye. 4. Ciliary body – intrinsic muscle; smooth muscle fibers support & modify lens shape 5. Iris – colored portion of eye formed by circularly and radially arranged smooth muscle fibers; regulates amount of light entering the eye by constricting or dilating the pupil

6. Pupil – rounded opening of the iris through which light passes 7. Retina – innermost layer of the eye; lines its surface and contains photoreceptors (cells responsible for converting light into nerve impulses – rods & cones) 8. Lens – flexible, biconvex, crystal-like structure that brings rays of light into focus and produces an image on the retina

Suspensory ligament – holds the lens in place; attached to the ciliary body, which controls the amount of tension exerted on the lens

Aqueous humor – watery fluid that provides nutrition and helps maintain the shape of the cornea; found in the smaller, anterior chamber of the eye

Vitreous humor – thick, gel-like substance that fills the largest chamber of the eye and helps to hold its spherical shape

optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because thereareno rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye.

• Blood supply: Carotid artery Ophthalmic artery Cilliary artery & Central retinal artery Eye

VENOUS DRIANAGE : OPTHALMIC VEINS, ORBITAL VEINS, VORTEX VIENS, RETINAL VEIN, ANGULAR VEIN.

INNERVATION : Opthalmic Nerve, Oculomotor Nerve, Maxillary Nerve, Frontal Nerve,