Post on 13-Apr-2016
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ANATOMY & PHYSIOLOGY OF THE EYEBALL
Department of OphthalmologyBrawijaya University
2008
School Rules• Pay Attention• Be Silent
External landmark of the eye
Medial canthus
Limbus
Orbital section of lid
Lateral canthus
Tarsal section of lid
Internal part of the eye
The ConjunctivaTransparent mucous membrane :• Palpebral conjunctiva
Posterior surface of the eyelid• Bulbar conjunctiva
Allows eye movement• Fornices conjunctiva
Junction between palpebral conjunctiva and bulbar conjunctiva
The Conjunctiva
Bulbar conjunctiva
Fornices conjunctiva
Palpebral conjunctiva
The conjunctivaHistology :• Conjunctival epithelium :
– Surface epithelial : mucous secreting goblet cells proper dispersion precorneal tear film
– Basal epithelial • Conjunctival stroma :
– Adenoid layer : follicle-like structure– Fibrous layer : papillary reaction
The Conjunctiva
Papillary reaction
Follicular reaction
The conjunctiva• Blood supply :
– Artery : Anterior cilliary & palpebral– Anastomose with vein
• Nerve supply : – N. Trigeminus, ophthalmic division
• Lymphatics :– Join with eyelids lymphatics
The Sclera & Episclera• Sclera :
– collagen ↑↑• Episclera :
– Blood vessel ↑↑ to nourish sclera• Blood supply :
– Artery posterior cilliary (short & long)• Nerve supply :
– Cilliary nerve
The CorneaTransparent :• Uniform structure• Avascularity• Desturgence
The Cornea
The Cornea• Source nutrition for the cornea :
– Vessel of the limbus– Aqueus humor– Tears
• Sensory nerve :– N. Trigeminal, ophthalmic division
Uveal tract• Uvea : Iris, Cilliary body, Choroid• Iris :
– Control the amount of light entering the pupil• Cilliary body :
– Formation of the aqueus• Choroid :
– Between retina and sclera– Blood vessel ↑↑
Uveal Tract
Cari gbr lain
The Lens • Biconvex
• Avascular• Colorless• Transparent• Thick : 4 mm : 9 mm• Suspended by
zonula zinii
The Lens Lens has ability adjust its focus from
distance to near object because lens has ability to change shaped
Accomodation
The vitreous• Clear, avascular,gelatinous body• Vitreous contains water (99%), collagen,
hyaluronic acid• Vitreous base : straddles the ora serrata• Vitreous body : central & cortex vitreous • Outermost part of the vitreous (hyaloid) :
Vitreous cortex, divided into anterior cortex & posterior cortex
The vitreous
The Retina• Thin membranous structure that lines
the posterior aspect of the eye• Divided : central zone & peripheral
zone• Retinal base : anterior ora serrata posterior N. opticus• Retinal cells are stratisfied in 10 layers
The Retina
The Retina• Internal limiting membrane• Nerve fiber layer• Ganglion cell layer• Inner plexiform layer• Inner nuclear layer• Outer plexiform layer• Outer nuclear layer• Photoreceptor cell (rod &
cone)• Retinal pigment epithelium
(RPE)• Bruch membrane
Photoreceptors of the retina• ROD :
– Perifer >>– Scotopic vision
(vision in dim light
• CONE :– Central >>– Photopic vision
(vision in bright & color)
The Optic Nerve (N. II)• Part of anterior
visual pathway (optic nerve, optic chiasm, optic tract)
• Light retina optic nerve brain
RED EYE
Department of OphthalmologyBrawijaya University
2008
Various types of red eye• Conjunctival injection • dilatation of posterior conjunctival
vessel• Fornices limbus• Bright red• Epinephrine test ( + )
Various types of red eye• Perilimbal (circumcorneal) dilatation :
cilliary flush• Limbus fornix• Epinephrine test ( - )
Various types of red eyeEpiscleral injection Dilatation of episcleral
vessel Pink-purple
Various types of red eyeScleral injection dilatation of deeper episcleral
vessel Purple bluish discoloration
Various types of red eye• Subconjunctival bleeding rupture of the
vessel ( extravasation of the blood ) Bright homogenous localized red eye
Common causes of red eye• Mild irritation of the eye• Acute conjunctivitis• Acute anterior uveitis• Acute glaucoma• Corneal trauma or infection
Mild irritation of the eye
• Symptom :– Red eye– No pain– No visual
disturbance– No discharge
• Sign :– Conjunctival
injection diffiuse, more toward fornices
– Others : within normal limit
Acute Conjunctivitis• Symptom :
– Red eye– Foreign body
sensation– Itch– No visual
disturbance– Discharge :
moderate to copious
• Sign :– Conjunctival
injection diffiuse, more toward fornices
– Discharge– Papillary reaction– Follicular reaction– Cornea : clear
Acute Conjunctivitis
Acute Anterior Uveitis• Symptom :
– Red eye– Pain : moderate– Visual disturbance :
slightly blurred– No discharge
• Sign :– Conjunctival
injection diffuse, mainly circumcorneal
– Cornea : usually clear
– Pupil size : small
Acute Anterior Uveitis
Acute Glaucoma• Symptom :
– Red eye– Pain : severe– Nusea, vomiting– Visual disturbance :
markedly blurred– No discharge
• Sign :– Conjunctival injection
diffiuse– Cornea : Steamy– Pupil : moderately
dilated & fixed– Intra ocular pressure ↑
Acute Glaucoma
Corneal infection and Trauma• Symptom :
– Red eye– Pain : severe to
moderate– Discharge : watery or
purulent– Visual disturbance :
usually blurred
• Sign :– Conjunctival
injection diffuse– Cornea : change in
clarity related to cause
– Pupil : normal
Corneal infection
Corneal trauma