visual system - univerzita karlovaanatomie.lf3.cuni.cz/centralni_prezentace/smysly-oko_eng.pdf · =...

Visual system

Oculus et structurae

pertinentes

© David Kachlík 30.9.2015

Odilo Redon© David Kachlík 30.9.2015

Orbita = Orbit

• tetrahedral pyramid tilted dorsally

• aditus x apex

• 10 openings + their contetnt

• m. orbitalis Mülleri – smooth muscle in the

fissura orbitalis inferior

• content: eyeball, oculomotor muscles, fat

pad and related structures


Orbita – osseous walls

• cranially: pars orbitalis o. frontalis (fovea trochlearis

+ spina trochlearis, incisura/foramen

frontalis/supraorbitalis, fossa glandulae lacrimalis),

ala minor o. sphenoidalis (fissura orbitalis sup.)

• medially: processus frontalis maxillae (fossa sacci

lacrimalis), os lacrimale, lamina orbitalis o.

ethmoidalis (foramen ethmoidale ant. et post.), ala

minor o. sphenoidalis

• laterally: facies orbitalis o. zygomatici (foramen

zygomaticoorbitale), facies orbitalis alae majoris o.

sphenoidalis © David Kachlík 30.9.2015

Orbita – osseous walls

• caudally: facies orbitalis o. zygomatici,

facies orbitalis corporis maxillae (sulcus et

canalis infraorbitalis, fissura orbitalis inf.),

processus orbitalis o. palatini

• aditus orbitae → apex orbitae

• orbita is divided by theoretical planes into

3 levels© David Kachlík 30.9.2015

Orbita – related structures

• medially: cellulae ethmoidales (via very

thin lamina orbitalis ossis ethmoidalis)

• caudally: sinus maxillaris

• cranially: fossa cerebri anterior

• dorsally: sinus cavernosus + fossa

pterygopalatina


Visual system

• bulbus oculi = eyeball

• structurae pertinentes oculi =

related structures of the eye

• topography: regio orbitalis

• development


Eyeball

• tunica fibrosa

(externa)

• tunica vasculosa

(media)

• tunica interna

(nervosa)

• corpus vitreum

(vitreous body) +

lens


Eyeball

• polus anterior,

posterior

• equator x meriadiani

• axis bulbi externus,

internus

• axis opticus (= „linea

visus“)


Tunica fibrosa (externa)

• sclera

• cornea


Tunica fibrosa (externa)Sclera

• dense connective tissue (= reticulum trabeculare),

collagen fibres, fibroblasts, ground substance

• lamina episcleralis, substantia propria, lamina

fusca

• lamina cribrosa (entrance of n. II.)

• 5/6th of the eyeball surface, ø 2,2 cm

• sinus venosus sclerae (canalis Schlemmi s. Lauthi)

• sulcus sclerae – sclerocorneal junction = limbus

corneae (angulus sclerocornealis)© David Kachlík 30.9.2015

Tunica fibrosa (externa)Cornea

• perfectly transparent, non-vascular

• limbus, vertex

• 5 layers– epithelium anterius cornae (stratified squamous ep.)

– lamina limitans anterior (Bowman´s membrane)

– substantia propria corneae

– lamina limitans posterior (Descement´s membrane)

– epithelium posterius corneae („endothelium“)

• 11 x 12 mm - physiological astigmatism


Tunica vasculosa (media)

= Uvea

• choroidea

• corpus ciliare (ciliary body)

• iris



= Choroidea

• lamina suprachoroidea (= lamina fusca sclerae)

• spatium perichoroideum

• lamina vasculosa (choroideal stroma)

– larger vessels, connective tissue, smooth muscle cells,

nerves

• lamina choriocapillaris

– capillaries

• lamina basalis = Bruch´s membrane

– BM of pigment epithelium and capillaries + connective

tissue © David Kachlík 30.9.2015


= Corpus ciliare

• annular shape, triangular profile

• processus + plicae ciliares

• orbiculus (external part), corona (internal part)

• smooth musculus ciliaris– fibrae meridionales,

radiales, circulares, longitudinales © David Kachlík 30.9.2015

Tunica vasculosa (media)= Corpus ciliare

• stroma– m. ciliaris: parasympathetic accomodation

focus at near

(focus at far is assured with the elastic choroidea)

– capillaries and nerves supplying the muscle

• epithelial cover – production of humor aquosus– BL – continuation of Bruch´s membrane

– pigment epithelium – (continuation of pigm. epith. of retina)

– cilliary canal

– nonpigment epithelium (continuation of sensory epith. of retina)

– BL

– fibrae zonulares – fixation of lens


Tunica vasculosa (media)= Iris

• annular and flat shape

• function of photograph stop (shutter)

• margo ciliaris (external), m. pupillaris (internal)

• pupilla

• anulus iridis major + minor (containing circulus

arteriosus iridis major + minor)

• m. sphincter pupillae (parasymp.) – miosis

(circular)

• m. dilatator pupillae (symp.) – mydriasis (radiate)© David Kachlík 30.9.2015


= Iris

• plicae iridis, stroma iridis

• anterior surface

– no epithelium cover

– fibroblasts and melanocytes (colour)

– dentate line – remnant of membrana pupillaris

Wachendorfi

• posterior surface

– 2 layers of pigment epithelium

– internal pigment

– external myoepithelial

• m. sphincter pupillae

• m. dilatator pupillae


Lens

• polus anterior, posterior

• axis, equator, radii (seams in shape of Y and

inverted-Y)

• capsula lentis

• substantia lentis – cortex, nucleus

• zonula ciliaris Zinni

– fibrae zonulares

– spatia zonularia

catharact - replacement© David Kachlík 30.9.2015

Lens

• transparen biconvex nonvascular structure

• capsula lentis – similar to BL

• epithelium lentis – unilayered cubic– anterior surface only

• substantia lentis– cortical – contains oblong cells (fibres) with organels

and nucleus

– nuclear – cellular fibres without organels and nucleus

– cells contain specific proteins (filensin, crystallins)


Accomodation

• focus at near

– contraction of m. ciliaris

– fibrae zonulares relax

– lens bulges

– parallel contraction of m. sphincter pupillae (=

miosis)

• focus at far

– vessels tonus keeps fibrae zonulares tightened

– lens is flatened

– contraction of m. dilatator pupillae (= mydriasis)© David Kachlík 30.9.2015

Corpus vitreum = Vitreous

body• membrana, stroma, humor vitreus

• 99% of water

• hyaluronic acid, collagen fibres

• cells – hyalocytes – during development only!

• no regeneration ! – in trauma flows out and replaced with aqueous humor

• canalis hyaloideus Cloqueti – remnant of fetal arteria hylaloidea

• fossa hyaloidea

• maintains the internal eyeball pressure, compress retina to the choroidea© David Kachlík 30.9.2015

Humor aquosus

= Aqeous humor

• produced by corpus ciliare

• absorbed in angulus iridocornealis

• 0,2-0,3 ml of pellucid and colourless fluid

• daily production - 3 ml

• content: 0,7-1,2% NaCl, glucose and urea traces

(0,1%), no proteins!

• corresponds to the lymph inside the eyeball

• intraocular pressure: 14-17 mmHg

intraocular pressure compression of retina

glaucoma © David Kachlík 30.9.2015

Camerae bulbi = Chambers of

eyeball

• camera postrema s. vitrea– between corpus ciliare, lens and retina

– contains corpus vitreum

– spatium retrozonulare

• camera posterior– between iris, lens and corpus ciliare

– contains and produces humor aquosus

• camera anterior– between cornea and iris

– angulus iridocornealis

– contains and absorbs humor aquosus© David Kachlík 30.9.2015

Angulus iridocornealis

= Iridocorneal angle

• in site of sclerocorneal junction

• trabecular net in the posterior wall = spatia anguli i.c. = Fontana´s spaces

• no direct connection to Schlemm´s canal

• reabsorption of humor aquosus

• maintains the intraocular pressure

• !!! no application of parasympatheticolytics in patient with glaucoma !!!


OCT

Optic

coherent

tomograph

y

measurement

s of light

reflexion © David Kachlík 30.9.2015

Break


Tunica interna (nervosa)

= Retina• pars caeca

– pars iridica

– pars ciliaris

• ora serrata

• pars optica – 11 layers

– pigment part

– sensory part


Tunica interna (nervosa)Retina – pigment part

• unilayered cubic epithelium

• cells with thight junctions

• apical cell parts contain melanin granules

• encompass the external segments of sensory

cells

• interfotoreceptor matrix

nutrition of cells, regeneratin of fotopigment,

degradation of membranous discs© David Kachlík 30.9.2015

Tunica interna (nervosa) Retina – sensory part

• light-sensitive neurons (transducers)

– rods and cones

• trasmission neurons (integraters)

– bipolar and ganglionic cells

• association neurons

– horizontal and amacrinne cells

• suppoting cells (glia)

– Müller´s cells


Tunica sensoria (interna)Rods = Bacilli

• synaptic disc

• axon

• nucleus

• internal segment

– GA, ER, MIT; synthesis of ATP and rhodopsin

• external segment

– membranous discs with fotopigment

– migrate externally until the separate

black and white vision© David Kachlík 30.9.2015

Tunica sensoria (interna)Rods = Coni

• synaptic foot

• fotopigment - iodopsin

• external segment

– membranous discs with fotopigment• communicate with environment

• colour vision– 3 types of cones

– „blue“ – 420 nm

– „green“ – 535 nm

– „red“ – 565 nm© David Kachlík 30.9.2015

Tunica sensoria (interna)Transmisison neurons (Integraters)

• Bipolar cells

– rod-like bipolar cells

– cone-like bipolar cells – dwarf x diffused

– contacts with ganglionic cells

• Ganglionic cells

– diffused type – contact with more bipolare cells

– dwarf type – contact with dwarf bipolare cell

– axons of ganglionic cells form nervus opticus


Tunica sensoria (interna)Association neurons

only neuritic processes – in both directions

• horizontal cells

– contacts with rods and cones

• amacrinne cells

– contacts with bipolar and ganglionic cells

modification and synchronization of signal


Tunica sensoria (interna)Supporting cells

• Müller´s cells

– macroglia

– their BL = membrana limitans interna

– zonulae adherentes with rods and cones

• = membrana limitans externa


Tunica sensoria (interna)Layers of optic part of retina

• 11 layers

!!! do not be frightened !!!


Tunica sensoria (interna)

Layers of optic part of retina

• stratum pigmentosum (1.)

• stratum nervosum (2.-10.)

– stratum segmentorum externorum et internorum(2.)

– stratum limitans externum (3.)

– stratum nucleare externum (4.)

– stratum plexiforme externum (5.)

– stratum nucleare internum (6.)

– stratum plexiforme internum (7.)

– stratum ganglionicum (8.)

– stratum neurofibrarum (9.)

– stratum limitans internum (10.)© David Kachlík 30.9.2015

Tunica interna (nervosa)

Specific spots of retina

discus n. optici (= blind spot)

• n. II leaves the eyeball

• no light-sensitive cells

excavatio disci


Tunica sensoria (interna)Specific spots of retina

• fovea centralis („macula lutea;yellow spot“)

–distant layers diverted laterally

–sharpest and most brilliant colour vision spot

–cones only (100.000 cones)

foveola (2500 cones)


OCT

Optic

coherent

tomograph

y


OCT


OCT

ABRUPTIO

RETINAE


Arterial supply of the eye

a. carotis interna a. ophtalmica

• aa. ciliares posteriores breves choroidea

• aa. ciliares longae (24) corpus ciliare +

iris

• aa. musculares aa. ciliares ant., a.

epiclerales, aa. conjuctivales lat.

• a. centralis retinae retina

• a. lacrimalis aa. palpebrales lat.

• aa. palpebrales med. aa. conjuctivales

med.


Vasa sanguinea retinae

– fundus oculi

a. centralis retinae

arteriolae

• a. temporalis sup.+inf.

• a. nasalis sup.+inf.

• a. macularis sup.+inf.

(+ media)

veins correspond to

arteries, they often

cross


A. cilioretinalis (cilioretinal

a.)• present in 10-33% of eyes

• branches from the a. ciliaris posterior brevis

• exits the discus n.II separately from a. centralis retinae

• additional supply to macula lutea from choroidal circulation

• provide a small amount of blood supply to the retina when a. centralis retinae is occluded

• 90% located temporally, 10% nasally

• occlusion of a. cilioretinalis → central visual loss

• occlusion of a. centralis retinae → spare central vision and macula lutea


A. cilioretinalis

(cilioretinal a.)


Venous drainage of eye – 3

directions

• vv. episclerales

• vv. ciliares ant. vv. sclerales sinus

venosus sclerae Schlemmi s. Lauthi

• vv. vorticosae (4 in quadrants of eyeball)

• v. centralis retinae

v. ophthalmica sup. sinus cavernosus

v. ophthalmica inf. plexus pterygoideus

v. angularis v. facialis v. jugularis int.

! danger of inflammation spreading !© David Kachlík 30.9.2015

Nervous supply of eye

• n. opticus – special sensory– pars intraocularis, canalis, itracranialis

– vagina interna, externa

• n. ophthalmicus nn. ciliares longi –somatosensory

• n. lacrimalis, n. frontalis, n. nasociliaris – for surrounding structures

• nn. ciliares breves ganglion ciliare – autonomic (visceromotor)

(sympathetic fibres non-interpolated, parasympathetic interpolated)

• n.III., n. IV., n.VI – somatomotor


Nervus opticus

• evagination of diencephalon (thalamus

opticus)

• axons separated with endoneurium

• covered with meninges

• a. et v. centralis retinea runs inside the

nerve


VISUAL PATHWAYProjection → Ascendent → Sensoric

4 - neuronal, partially crossed

1. neuron: rod and cones of retine

2. neuron: bipolar cells

3. neuron: ganglional cells n. II chiasma opticum corpus geniculatum laterale

4. neuron: cells in corpus geniculatum laterale tractus geniculocorticalis (= radiatio optica Gratioleti) lobus occipitalis, area 17 (around sulcus calcarinus)• Meyer´s loop into temporal lobe© David Kachlík 30.9.2015

VSIUAL PATHWAY

branches from 3rd neuron

• to hypothalamus (nucleus suprachiasmaticus) – converts optical

signals to highest vegetativ centres (seeing meal = salivation)

• pathways of pupillar reflex - through area pretectalis

• to nucleus accessorius dorsalis n. III /Edinger-Westphal/ -

parasymphatetic pathway with n. III ganglion ciliare nn.

ciliares breves m. ciliaris et m. sphincter pupillae /miosis +

accomodation/

• to reticular formation tractus reticulospinalis centrum

ciliospinale /Budge/ C8-Th1 sympathetic pathway in truncus

symphaticus ganglion cervicale superius plexus caroticus

internus et ophtalmicus nn. ciliares breves m. dilatator

pupillae /mydriasis/

• pathway for convergence nucleus interstitialis /Cajal/

fasciculus longitudinalis medialis nuclei of all ophtalmogyric

nerves

• tectal optic circuit - tractus tectospinalis (control of synkinesis of


Structurae oculi accessoriae

= Related strctures of eye• Apparatus ligamentosus

• Palpebrae = Eyelids

• Conjunctiva

• Apparatus lacrimalis

• Apparatus muscularis

• Supercilium


Apparatus ligamentosus

• periorbit

• vagina bulbi (= capsula Tenoni)

– lig. suspensorium bulbi

• spatium episclerale

• corpus adiposum orbitae

• fasciae musculares


Tunica conjunctiva

• t.c. bulbi x t.c. palpebrarum

• fornix superior, inferior

• continuation of epithelium of cornea, dorsally to

the eyelid, covers anterior surface of the eyeball

• stratified cylindric epithelium

• contains goblet cells

• glanduale conjuctivales Wolfringi

• caruncula lacrimalis


Víčka = Palpebrae

• palpebra superior, inferior

• tarsus superior (10 mm), inferior (5 mm)

• lig. palpebrale med. (2 pruhy) + lat.

• facies ant.+post., rima palpebrarum, commissura

palp. med.+lat., limbus ant.+ post.

• angulus oculi med.+ lat.

• m. tarsalis sup. (Mülleri) + inf. – smooth muscles

• pars palpebralis m. orbicularis oculi - n. VII

• m. levator palpebrae superioris - n. III

• cilia © David Kachlík 30.9.2015

Palpebrae = Eyelids

• palpebra superior, inferior

• tarsus superior (10 mm), inferior (5 mm)

• lig. palpebrale med. (2 bands) + lat.

• facies ant.+post., rima palpebrarum, commissura

palp. med.+lat., limbus ant.+ post.

• angulus oculi med.+ lat.

• m. tarsalis sup. (Mülleri) + inf. – smooth muscles

• pars palpebralis m. orbicularis oculi - n. VII

• m. levator palpebrae superioris - n. III

• cilia © David Kachlík 30.9.2015

Palpebrae = Eyelids

• external cutaneous part– keratinizing stratified squamous

epithelium

– gl. sebaceae Zeissi • inflammation - hordeolum

– cilia + gl. ciliares Molli• apocrinne glands

• m. orbicularis oculi

• tarsus– fibroelastic plate

– gl. tarsales Meibomi• sebaceous glands - chalazion

• internal conjunctival part– sulcus et epithelial transition


Apparatus lacrimalis = Lacrimal

apparatus

• glandula lacrimalis

– pars orbitalis + palpebralis

– 12-15 separate ductuli excretorii

• glandulae lacrimales accessoriae Krausei

• rivus lacrimalis

• lacus, papilla, caruncula lacrimalis

• puctum, canaliculus lacrimalis

• saccus lacrimalis ductus nasolacrimalis (plica lacrimalis Hasneri) meatus nasi inf.


Glandula lacrimalis

• tubuloacinar serous glands with

myoepithelial cells


Muscular apparatus

• mm. recti bulbi: sup., inf., med., lat. (VI.)

• mm. obliqui bulbi: inf., sup.(IV.)

– /fovea trochlearis, spina trochlearis, trochlea,

vagina m.o.b.s./

• m. levator palpebrae sup. (pars spf.+prof.)

• n. III – other 5 muscles

• smooth svaly: m. orbitalis Mülleri, m. tarsalis

sup. Mülleri + inf.© David Kachlík 30.9.2015

Movements of the eye-

ball I.movements around axis = ductions

• around vertical axis:

– adduction (internal)

– abduction (external)

• around horizontal axis:

– elevation (sursumduction; supraduction): up

– depression (deorsumduction; infraduction):

down

• around sagittal (antero-posterior) axis:

– intorsion (incykloduction): tilted internally

– extorsion (excykloduction): tilted externally© David Kachlík 30.9.2015

Movements of the eye-ball

II.paired movements (both eyes working together)

• simultaneous movement of both eyes in the same direction = version (conjugate movements)– dextroversion (to the right) + levoversion (to the left)

– supraversion (sursumversion) + infra/deorsumversion (up + down)

– dextro/levoelevation + dextro/levodepression (up/down and to side)

– dextro/levocykloversion (rotation to the right/left)

• simultaneous movement of both eyes in opposite directions = vergence (disconjugate movements), convergence = both eyes moving nasally or inward , divergence = both eyes moving temporally or outward

• strabismus; heterotropia; squint = one eye constantly is turned inward (“crossed-eye”), outward (“wall-eye”), upward, or downward. http://www.tedmontgomery.com/the_eye/eom.html


Movements of the eye-ball


Strabismus concomitans

• esotropia (s. convergens)

• exotropia (s. divergens)

• hypertropia (s.

sursumvergens)

• hypotropia (s.

deosumvergens)© David Kachlík 30.9.2015

Development of visual system

• neuroectoderm of the forebrain

• superficial ectoderm of head

• mesoderm in between

• cells from neural crest



• primordia from beginning of 4th week (22nd day)

• formation of optic grooves in the region of forebrain

• grooves deepen in optic vesicles

• formation of optic peduncle

• induction of ectoderm = thickening

• formation of lens (optic) placode



• envagination of lens (optic) placode

• formation of hollow lens vesicle without

connection to the external surface

• optic vesicles envaginate = optic cup

• envagiantion of optic pedicle and cup +

migration of vascular mesenchyme =

formation of vitreous vessels


Development of retina

• origin from optic cup

• external layer – pigment epithelium

• internal layer – proliferates into pars

nervosa

• intraretinal space – successively fades out

• inversion of retina


Development of n. II

• fibres from ganglionic cells growth through

the optic pedicle

• fissure (evagiantion) fades out


Development of corpus ciliare

• protrusion of both layers of optic cup

• pigment epithelium – from external layer

• non-pigment epithelium – from internal

layer

• ciliary canal – from optic cup cavity

• m. ciliaris and connective tissue – from

mesenchyme


Development of iris

• margin of eye cup

• external layer – smooth muscles

• internal layer –pigment epithelium


Development of

lens• from lens (optic) vesicle

– anterior surface – no change = epithelium anterius

– posterior surface – cells elongate as far as lumen disappers

• formation of primary fibres

• secondary fibres – derived from epitheliuum anterius cells

– capsula lentis – thickened BL of epitheliuum anterius

• a. hyaloidea – fades out

• pupillary membrane –covering lens – fades out


Development of camere bulbi

• camera anterior

– fissure between primordial lens and cornea

• camera posterior

– fissure in optic cup on sides of lens vesicle


Development of cornea,

choroidea and sclera• cornea

– superficial ectoderm

– mesenchyme

– cells of neural crest

• choroidea and sclera

– surronding mesenchyme


Development of palpebrae

• 6th week: cutaneous folds across cornea

• 10th week: both folds fuse

• 28th week: folds separate again

• inbetween: conjunctina adheres internally

• muscles: IInd branchial arch

• tarsus and glands from mesenchyme


Development of lacrimal glands

• evaginations of superficial ectoderm

• non-functionnal until 6th week

– newborn does not water in eyes


finally…END !


visual system - univerzita karlovaanatomie.lf3.cuni.cz/centralni_prezentace/smysly-oko_eng.pdf · =...

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