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REPRESE NTE D T O:
DR. ZEESHAN AKBAR
BY:FAISAL SHAHZAD 14-ARID-2022
Eye of goat
ANATOMY Of EYEGOAT
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The eye or organ of vision usually it comprises of;
The eyeball or globe of the eye (Bulbus oculi)
The optic nerve Certain accessory organs The accessory organs are; Orbital fasciae and muscles The eyelids and conjunctiva, and The lacrimal apparatus
Eye:
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The bony walls of the orbit have been described in connection with the skull; the peri-orbita, a fibrous membrane which encloses the eyeball together with its muscles, vessels, and nerves may be appropriately included in the account of the fasciae
Connection with skull:
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The eyelids, upper and lower are movable folds of skin situated in front of the eyeball.
The upper lid more movable than the lower one, and its free interval between the lids is termed the palpebral fissure
The ends of the fissure are the angles/comissures , and are distinguished as medial or nasal, and lateral or temporal
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Eyelids or Conjunctiva:
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The third eyelid is situated at the medial angle of the eye.
It consists of a semi-lunar fold of the conjunctiva, known as the membrana nictitans,
which covers and partly encloses a curved plate of hyaline cartilage. Its marginal part is thin and usually more or less pigmented.
The deep part is narrower and thicker and is embedded in fat at the inner side of the eyeball
Cont...
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The skin of the eyelids is thin and freely movable, except near the free edge, where it is more firmly attached.
The underlying subcutaneous tissue is composed of fat.
The muscular layer consists chiefly of the elliptical bundles of the orbicularis oculi, with which are associated fibers of the supercilii in the upper lid and
the malaris in the lower lid.
Cont...
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At the medial side there is a fibrous band, the palpebral ligament, which is attached to the lacrimal tubercle and provides origin to some fibres of the orbicularis.
Cont...
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At the medial commissure a bundle detached from the orbicularis passes inward behind the lacrimal sac, and is known as the pars lacrimalis (Horner's muscle)
At the lateral side the fibrous layer is thicker and denser along the free edge of the lid, forming here the tarsus.
The tarsus provides insertion to a layer of unstriped muscle known as the tarsal muscle.
The tarsal glands (Glandulse tarsales) are partly embedded in the deep face of the tarsus.
Cont...
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The conjunctiva is the mucous membrane which lines the lids as palpebral conjunctiva (C. palpebrarum), and is reflected upon the anterior part of the eyeball as bulbar conjunctiva (C. bulbi); the line of reflection is termed the fornix conjunctiva.
Cont...
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there is a rounded pigmented prominence known as the lacrimal caruncle
about the size of a small pea, and is covered modified skin, connected with that of the medial commissure, from which project a number of hairs provided with sebaceous glands.
slit-like opening, the pictum lacrimal, which is the entrance to the lacrimal duct.
Lacrimal Caruncle:
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It is composed of:Lacrimal Gland Which secretes lacrimal fluidExcretory ducts of gland The pimcta lacrimalia are the entrances to the two
lacrimal ducts.Lacrimal ductsCanaliculiLacrimal sac Naso-lacrimal duct Which receive fluid & convey it to nostrils
Lacrimal Apparatus:
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The anterior margin bears stiff hairs termed the cilia (eyelashes).
On the upper lid the cilia are long and numerous except at its medial third, where they are very small or absent.
On the lower lid the cilia are often scarcely distinguish-able from the ordinary hairs
Cilia or Eyelashes:
Cilia
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Sensory Nerves branches of the ophthalmic and maxillary divisions of the trigeminus.Motor Nerves Orbicularis oculi, supercilii, and malaris
come from the facial nerve
Nerves:
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The straight muscles of the eyeball and the oblique muscles in part are enclosed in fibrous sheaths
Superficial fascia (Thin)Deep fascia Fascia bulbi (cover the posterior part of
eyeball)Levator palpebrae superiorisMuscles of the eyeball are seven in
number—four straight, two oblique, and a retractor
The Orbital Fascia & Ocular Muscles
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Obliquus dorsalis s. Superior (longest and narrowest of the ocular muscles)
Obliquus ventralis s. Inferior (wide and much shorter than the recti)
Retractor oculi (Surround the optic nerve)
Oblique & retractor Muscles:
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Rectus dorsalis s. superiorRectus ventralis s. inferiorRectus medialisRectus lateralisThey are all band-likearise close together around the optic foramendiverge as they pass forward to the eyeball.
Straight Muscles:
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situated in the anterior part of the orbital cavity
protected in front by the eyelids and conjunctiva, and in its middle by the complete orbital ring
related behind to the fascia bulbi, fat, and ocular muscles.
form approximately a spherecomposed of the segments of two spheres of different sizes
The Eyeball (Bulbus oculi):
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forms the anterior fifth of the fibrous tunictransparentcolorlessnon-vascularoval in outlineanterior surface is convexcentral part is termed the vertex comeae.posterior surface (Facies posterior) is
concaveThe margin (Limbus corneae) joins the scleracornea is thinnest at the vertex
Cornea:
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The retina or nervous tunic of the eyeball is a delicate membrane which extends from the entrance of the optic nerve to the margin of the pupil.
consists of three parts large posterior part• pars ciliaris retinae• Pars iridica retinae• optic papilla (Papilla nervi optici)area centralis retinae
The Retina:
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pigmented epithelium (Stratum pigmenti retinae)
arteria centralis retinae anastomotic branches from the short ciliary
arteriesveins accompany the arteries except in the
capillary plexuses; their walls consist merely of a layer of endothelial cells, around which are a lymph-channel and sheath.
Cont...
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anterior chamber posterior chamber The chambers are filled by the aqueous
humor clear fluid which consists of about 98% of
water, with a little sodium chlorid and traces of albumin and extractives.
It is carried off chiefly through the spaces in the zonula ciliaris (suspensory ligament of the lens) into the plexus venosus sclerae.
Chambers Of The Eye:
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vitreous body is a semifluid transparent substance situated between the
crystalline lens and the retina In front it presents a deep cavity, the fossa
hyaloidea, which fits the posterior surface of the lens
vitreous stroma vitreous humor The surface is covered by a condensation of
the stroma known as the hyaloid membrane
Refractive Media Of The Eyeball:
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crystalline lens is a biconvexEquator of the lens is almost circularAnterior surface is convexPosterior surface is much more strongly
curved than the anteriorThe central points of the surfaces are the
anterior and posterior poles and the line which connects them is the axis of the lens
zonula ciliaris is suspensory ligament of the lens
Cont...