ocular anatomy. eyeball orbit lacrimal apparatus extraocular muscles visual organ & visual...
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Ocular anatomy
Eyeball
Orbit
Lacrimal apparatus
Extraocular musclesvisual organ & visual pathway
Vascular supply to the eyeball
SectionⅠ
Eyeball
Orbit
• Frontal• Zygomayic • Maxillary• Ethmoidal• Sphenoid • Lacrimal• Palatine
Lacrimal apparatus
1. Lacrimal gland2. Lacrimal
passages• Lacrimal puncta• Lacrimal canaliculi• Lacrimal sac• Nasolacrimal duct
Extraocular muscles
• Medial rectus• Inferior• Lateral rectus• Superior rectus• Superior oblique• Inferior oblique
Extraocular muscles
visual organ
visual organ
Eyeball
appendages : eyelid , conjuncliva , lacrimal , ocular , orbitalis apparatus muscles ,
Wall
content : aqueous humor , lens , vitreous body
outer : cornea , sclera
media : iris , ciliary , choroid
inner : retina
visual retina pathway
Optic nerve
Optic chiasm
Optic tract
Lateral geniculate body
optic radiation
occipital lobeoptical center
visual pathway
Vascular supply to the eyeball
Artery• Central retinal artery,CRA• Ciliary artery,CA• Short posterior CA vein• Long posterior CA• Anterior ciliary CA 1. Central retinal
vein,CRV
2. Vortex vein
3. Anterior ciliary vein
Vascular supply to the eyeball
aqueous humorLens
Vitreous body
SectionⅡ
retina
Choroid
Ciliary body Iris
Cornea Sclera
Cornea
• Oval – transverse : 11.5 ~ 12mm
– vertical : 10.5 ~ 11mm
• curvature : anterior : 7.8mm
posterior : 6.8mm
• antisymmetry• thickness : centre : 0.5 ~ 0.55mm
periphery:1mm
• Refractive index : 1.3771
Refractive power: 43D 2 / 3 of total
Cornea
Histologic structure :
Cornea
Epithelium
Basement layer
Bowman’s membrane
Stroma
Descemet’s membrane
endothelium
1.Epithelium :– 50μm
– 5 ~ 6 layers
• Squamous cell
• Aliform cell
• Basal cell
– Renewing cycle≈7 days
Cornea
2.Bowman’s membrane :
• 12 μm
• No cell
• Collagen , matrix
• Scar
3.Stroma :– 500 μm
– 2 ~ 3 % corneal cell
– 1 % matrix ( GAGs)
– Fibrous lamina
• 200 ~ 250 layers
• Parallel to surface
• Parallel collagen fiber
• Ordered arrangement
– Scar
Cornea
4.Descemet membrane :– 10 ~ 12 μm
– No structure
– elasticcity
– Secreted by endothelial cell
– Basal membrane of endothelial cell
– regeneration
5.Endothelium :– 5 μm
– Monolayer hexagen
• 500 000 cells
• Stop miosis
• Tight junction
• Pump
Cornea
• Blood vessel:
– Limbus vascular net
– Inner avascularity
– Less nutrition
Cornea
• Innervation :
– One of the most full tissue
– ophthalmic nerve of Trigeminal nerve(N5)
• Sensory nerve
• Parasympathetic nerve
– demyelination
– Available when edema
Physiology
• Enegy
• Transparency maintaining
– Anatomy • avascularity, no pigment
• Epithelium ordered arrangement , no keratinization
• Stroma ordered arrangement
• Endothelium ordered arrangement
– Tight junction of endothelium
– Related hydration• pump
• Hydration of stroma
Physiology
Transpar
ency
Transpar
ency
Transpar
ency
Sclera
• Posterior 5/ 6 of fibrous mem• White , firm
• Forward connect cornea-corneoscleral limbus• Backward :optic nerve
– Sheath – Cribriform plate
• Thickness
Muscle attachment: 0.3mm
Nerve surrounding: 1.0mm
Histology
– Episclera : vascular contain
– Sclera stroma : collagen fiber
– Plate layer : pigment cell
Sclera
Physiologic function:
• Appearance maintaining
• Content protection
• refraction
Sclera
Corneoscleral limbus
• Transition zone:– ant : bowman`s terminal-descemet terminal
– pos : scleral spur / iris root vertical plane
• 1.5~ 2.0mm width
• appearance– Semitransparant zone
– White sclera
• Angle of AC
Angle of anterior chamber
• Ant-lateral:corneoscleral limbus
• Pos-medial:anterior ciliary and iris root
• Include:– Schwalbe line
– trabecular reticulum
– Schlenm cannel
– Scleral spur
– Ciliary zone
– Iris root
• Disc
• Chamber separation
• Puple : 2.5~ 4.0mm
• whorl
– Puple area
– Ciliary zone
iris
Histology
• Anterior surface layer
• Stroma layer• chromocyte
• sphincter muscle of pupil——parasympathetic nerve
• dilator muscle of pupil——sympathetic nerve• Pigmentary epithelium
iris
pupil
– Regulation of incident light volumn
– Depth of focus and aberration
iris
• Connect iris root and choroid
• Triangle – corona: 2mm
• Ciliary process: 40~ 80个– Pars plana: 4mm
• Muscle ——parasympathetic nerve– meridional fibers
– Radial fibers
– Circular fibers
Ciliary body
contraction:
– Accomodation
• Ring muscle contraction
• Suspensory ligament internal traction , loose
– IOP
• meridional fibers contraction
• Choroid shift forward , scleral spur draw backward
– Open AAC/scleral vein
– Choroid blood volumn↑
– Ciliary blood volumn↓
Ciliary body
• Full filled
• 0.2ml
• Refractive index: 1.3774
• Drainage path
– ciliary posterior chamber pupil anterior chamber trabecular Schlemm canal collection canal aqueous vein ciliary veins
– choroid
aqueous humor
• physiology
– dioptric media
– IOP maintain
– Uniform RI of conea
– metabolism
– accomodation
aqueous humor
choroid
• ora serrata —— optic disc
• Full of pigment and BV
• Bruch membrane
• nutrition , dark room
Histology
10 inner limiting membrane09 nerve fiber layer08 ganglion cell layer
07 inner plexiform layer
06 inner plexiform layer05 external plexiform layer
04 external;nuclear layer
03 outer limiting membrane02 retinal rod and cone cell layer
01 RPE
Lens
• Transparent , double convex mirror• Between pupil-iris and vitreous body
• Diopter : 19D– ant: 10mm
– pos: 6mm
• Axis length: 4mm
• D: 9mm
• RI: 1.4371
Lens
• Nonuniform RI
• Elasticcity body
• Accomodation intracapsular——RI
Vitreous body• Transparent colloid• 4.5ml• RI:1.3360≈aqueous humor• Tight junction site:
– Disc egde– Fovea surrounding– Basement of vitreous body– Posterior capsular ( youth)
• Cloquet canal– Lens posterior pole——in front of disc– Primary vitreous
• Transparent ,thin• Anterior rim : ora serrata• macula / fovea
– Posterior pole– Keen – RPE-pigment
• optic disk– Disc form– Nasal side of macula: 3mm– 1.5×1.75mm– optic cup C/D < 0.3
Retina
Special side:– Optic disc
• Only optic nerve fiber• Physiological blind spot
– macular• thinnest
• Only rod —— photopic vision , colour vision
• Other layers abscent
• Neuron singlet link
• keen
Retina