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ANAT D502 - Basic Histology

The Eye Pre-labrevised 11/19/0

Objectives:

1. Describe the structure of the eyelid and its associated, non-integumental (eye specific) gland.

. Describe!diagram the path of light through the eye.

". #no$ the structural organi%ation of the eye. Define the " coats!tunics of the eye and thedifferent structures $ithin the coats.

&. Describe the structural!functional organi%ation of the iris.

'. Define!identify the different layers of the retina.

. Describe the flo$ of liuid in the posterior and anterior chambers of the eye.

*lide:

s+& ye (orbit or peeper, money)s+ yelid (palpebrae, money)

/nde0 of images 

he eye is a sensory organ responsible for vision. /t can be divided into three tunics that surround

fluid-filled spaces. hese tunics are the corneosclera, uvea, and retina. he fluid-filled spaces

include the anterior and posterior chambers and the vitreous body, the latter being a gelatinousmass. he corneosclera or outermost coat is divided into the cornea and sclera. he sclera is

composed primarily of a collagen coat that is opaue and covers the posterior '!2s of the eye.

he cornea covers the anterior 1! of the eye is speciali%ed for light transmission. /n this regionof the eye, the coat is translucent due to its lac of vasculature and the organi%ation of the

collagen stroma. he middle coat or uvea can be subdivided into " parts: the choroid (posterior),

ciliary body (anterior), and iris (most anterior). he choroid is the largest component of the uveaand it covers the posterior !"rds of the eye. /t can be divided into four layers: the

suprachoroidal layer, vascular (vessel) layer, choroidocapillary layer, and 3ruch2s membrane

(basal comple0). he vascular layer contains arteries, veins, and pigmented melanocytes. hechoriodocapillary layer contains the capillaries and 3ruch2s membrane is essentially a thic basal

lamina that separates the choroid from the retina. he ciliary body and iris are in the anterioraspect of the eye. he ciliary body functions to produce the aueous humor of the posterior and

anterior chamber and contains a smooth muscle mass involved in regulating lens thicness(focusing the image). he lens of the eye is suspended by very thin ligaments that attach to the

ciliary processes, and the thicness of the lens is modulated by smooth muscle $ithin the ciliary

 body. he iris covers the lens and regulates the amount of light entering the orbit through the pupil. he space bet$een the lens and the iris is called the posterior chamber into $hich aueous

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humor from the ciliary body is secreted. he space bet$een the iris and the cornea is called the

anterior chamber.

he last, most interior tunic of the eye is the retina. 4ithin this tunic there are several cell(nuclei) layers. he outermost, adjacent to 3ruch2s membrane of the choroid, is a single

 pigmented cell layer containing melanocytes. he ne0t layer is the photosensitive layercontaining the rod and cone cells responsible for transduction of photons (light intensity for rods

and light color for cones) into sensory input. his is follo$ed by the bipolar then ganglion celllayer. hese latter cells establish synapses $ith the photosensitive cells and integrate the visual

input. he ganglion cell a0ons join and form the optic nerve that e0its the eye in your blind spot

(optic dis or optic nerve papilla). he photosensitive retinal epithelia covers the posterior !"rdsof the orbit and is not uniform in all areas. 5t the optic disl there are no photosensitive cells, only

a0ons of the ganglion cells. his region is off the optical a0is and is your blind spot. 5t the

optical a0is the retina is thinner as the bipolar and ganglion cell nuclei are absent and this regioncontains primarily cone cells. his is the region of the retina that has the greatest visual accuracy.

5t the anterior aspect of the retina, the light-sensitive neural tissue (photosensitive cells, bipolar,

and ganglion cells) is lost and this transition %one is called the ora serrata (appears serrated lie astea nife). 4ithin the retina and uvea, there are pigmented cells $hose function is to absorb

light and prevent light scattering $ithin the orbit to enhance visual acuity. 6nlie integument, the

 pigment remains in the melanocytes instead of being taen up by surrounding cells.

he eye is covered by the eyelid $hich affords both mechanical and chemical protection of theeye. 4ithin the eyelid is a modified sebaceous gland called the tarsal (7eibomian) gland $hich

secretes the lipid component of tear film.

4e $ill first study the eyelid (s+). 0amine the lid at lo$ po$er and e0amine the bulbous

region of the lid $ith its eyelashes. 3ehind the eyelashes and near the internal aspect (peeper

side) of the lid is an alveolar gland. his is the tarsal gland $hich is a modified sebaceous glandthat does not secrete onto the lashes but rather releases it greasy product at the margins of the

eyelids onto the conjunctiva. he secretory alveoli connect via short ducts to a long e0cretoryduct that is lined $ith stratified suamous epithelia. he tarsal gland and its duct run nearly the

full length of the palpebra in and inferior - superior orientation $ithin the tarsal plate (see belo$)

and thus the name tarsal gland. /f you migrate further up the lid you $ill note essentially &

layers: thin sin covering the outer aspect, a layer of seletal muscle (orbicularis oculi), a plate of fibroelastic connective tissue called the tarsal plate, and the inner layer ne0t to the eye $hich is

the conjunctiva. he tarsal plate is relatively rigid and made of dense irregular collagenous

connective tissue and elastic connective tissue. /n particularly gifted people, the palpebra can beeverted sho$ing the palpebra conjunctival epithelia (inner aspect of lid) and the rigidity of the

tarsal plate holds the palpebra in this position. he palpebra conjunctiva rests upon the tarsal

 plate and its epithelia is stratified $ith goblet cells $hile its lamina propria (subconjunctivallayer) is highly vasculari%ed.

8ets open the lid and study the peeper (s+&). 9or the lined images, the photons are passing from

left to right . 5lso, reali%e that the eye is a sphere and not all sections are going to sho$ all the

features of the eye to good advantage (/ used & different sections for the lined images). 4e $illvie$ the features of the eye as light $ould progress through it. 8oo at the section of the eye

7/17/2019 ANAT D502

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$ith your naed eye. he most obvious structure that you $ill note is the lens as it is a large

eosinophilic disc at the anterior aspect of the eye. 7ore anterior to that is a space follo$ed by a

layer of avascular tissue. his layer is the cornea. here are ' layers to the cornea and startingfrom the outside, the layers are: the corneal epithelium (stratified suamous epithelia), 3o$man2s

membrane upon $hich the corneal epithelium rests, corneal stroma (dense regular collagenous

connective tissue $ith fibroblasts), Descemet2s membrane and the corneal endothelium (simplelo$ cuboidal epithelia) that rests upon Descemet2s membrane. he corneal endothelium faces a

space that is the anterior chamber of the peeper. 9ollo$ the cornea to its margin $here it joins the

sclera (corneoscleral junction or limbus) and you $ill note a change in the epithelia andunderlying tissue as it changes into the bulbar conjunctiva. rogress into the deep stroma of the

sclera at the limbus and you $ill note a canal $ithin the sclera and a mesh$or of smaller

openings in direct communication $ith the anterior chamber. he larger lumen $ithin the stroma

of the sclera is the canal of *chlemm $hile the smaller openings in direct communication $iththe anterior chamber is called the trabecular mesh$or (spaces of 9ontana). hese spaces and the

canal form the outflo$ path for aueous humor out of the anterior chamber and eventually into

the venous system.

he ne0t most obvious structure that projects into the anterior chamber near the trabecular

mesh$or and canal of *chlemm is the iris. /t is a projection arising from the anterior region of

the ciliary body. he iris projects over the lens and its interior margin defines the pupil and the

iris in toto defines the anterior chamber from the posterior chamber. ;ear the pupil, the iriscontains a loose, vascular connective tissue stroma $ith interspersed melanocytes, follo$ed by

an eosinophilic layer made of smooth muscle and lastly, a highly pigmented layers pro0imal to

the lens. he eosinophilic layer is made of circularly arranged smooth muscle and is called thesphincter pupillae muscle. /ts contraction decreases pupil diameter. 5s you progress to the base

of the iris (to$ard the *chlemmer), the sphincter pupillae muscle stops and a very thin

eosinophilic layer is noted that rests upon the highly pigmented layer   pro0imal to the pupil. his

eosinophilic layer is called the dilator pupillae muscle. /t represents the radially arrangedmuscular processes of the myoepithelial anterior epithelium. /ts contraction opens (dilates) the

 pupil. hus, these <muscles< are involved in controlling pupil diameter and thus the amount of

light that passes into the lens.

he lens is an avascular structure just posterior to the iris. he lens is encased $ithin a capsule

(lens capsule) and beneath this capsule and on the e0terior aspect is a single layer of cuboidal

cells called the subcapsular epithelium. he capsule is a thic basement membrane produced bythe subcapsular epithelium. 3eneath the epithelium and maing the main body of the lens are the

lens fibers $hich are enucleated cells. hese cells are full of crystallins. 5t the euator (midline)

and near the periphery of the lens, you $ill observe nuclei $ithin the body of the lens and these

are cells derived from the subcapsular epithelium that are giving rise to the mature lens fibers(nascent lens fiber cells). /n this region, you $ill also note thin fibers that connect to the lens

capsule. hese fibers are called %onular fibers and connect the lens to the ciliary processes that

 project from the ciliary body. hese fibers are o0ytalin fibers made by the ciliary body epithelia.=ontraction of the ciliary muscles (to$ards the anterior aspect of the eye) rela0es the tension on

the %onular fibers allo$ing the lens to rela0 (become thicer).

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he ciliary body is a thicening of the anterior aspect of the uvea. he main mass of the ciliary

 body is formed by its stroma $hich contains vasculature and melanocytes and a large mass of

smooth muscle, the ciliary muscle. he epithelium of the ciliary body is bi-laminar and it produces the aueous humor and releases it into the posterior chamber> it also produces the

%onular fibers that anchor the lens. he outer pigmented layer of the epithelium is continuous

$ith the pigmented layer of the retina (retinal pigmented epithelium).

9ollo$ along the epithelia along the lateral $all from the ciliary body to the posterior aspect ofthe eye and you $ill note a change in the epithelia $here it thicens and sho$s obvious lamina

of nuclei. his region is called the ora serrata is the anterior most aspect of the neural retina

(photosensitivity starts here). 4hen vie$ed from the inside out, this junction is serrated (lie astea nife at *t. lmo2s), hence the name. 5s you progress to the posterior aspect of the eye, you

$ill note that the epithelia thicens and is typically thicest at the most posterior aspect of the

eye. 0amine the layers of the eye in this region. he inner most layer is the retina $hich can besubdivided into the neural retina (photosensitive cells and relay neurons) and the retinal pigment

epithelium (pigmented cells). he neural retina has three lamina of nuclei $ith essentially nerve

cell processes filling the space bet$een the nuclear lamina. he light first passes through theganglion cell layer , then through the bipolar cell layer (inner nuclear layer), and lastly to the

 photoreceptor cell layer (outer nuclear layer).  /n terms of trendy terminology, these cells e0press

the photosome (proteins involved in transduction of light to an electrical signal). he light then

hits the outer segment of the rods and cones that contains the photoreceptors of the cells. /f thelight is not absorbed by the photoreceptors it is absorbed by the pigmented retinal epithelial cells

that define the posterior most aspect of the retina proper. hese cells form a single layer of nuclei

that rests upon 3ruch2s membrane of the choroid region of the uvea. he choroid is characteri%ed by its vascularity and presence of pigmented cells $ithin the stroma. he outermost aspect or

layer of the eye is the sclera $ith its fibrous stroma made of dense collagenous connective tissue

$ith interspersed fibroblasts.

*ome features of the retina $hich may not be readily apparent in your section includes thevasculature of the retina, the fovea and the optic dis. 0amine the retina and you may observe

some capillaries $ithin the ganglion cell layer . hese capillaries can be visuali%ed $ith an

ophthalmoscope, and they nourish the retina. 0amine the retina in the posterior aspect of theorbit and you may o bserve a thinning of the ganglion cell layer , if so, you are near the fovea. /f

you are at the fovea, only one cell nuclei layer $ould be present and it $ould be that of the

 photoreceptor cell nuclei. *ome$hat off the center of the optical a0is in the posterior orbit, youmay observe a region in $hich the retina is devoid of neural retina nuclei. his is the optic dis

(papilla) in $hich the ganglion cells a0ons join, e0it the orbit and form the optic nerve.

?opefully, you have enjoyed this visual tour of the cellular features of the orbit.

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ANAT D502 - Basic Histology

The Eye Pre-labrevised 11/19/0

Objectives:

1. Describe the structure of the eyelid and its associated, non-integumental (eye specific) gland.

. Describe!diagram the path of light through the eye.

". #no$ the structural organi%ation of the eye. Define the " coats!tunics of the eye and thedifferent structures $ithin the coats.

&. Describe the structural!functional organi%ation of the iris.

'. Define!identify the different layers of the retina.

. Describe the flo$ of liuid in the posterior and anterior chambers of the eye.

*lide:

s+& ye (orbit or peeper, money)s+ yelid (palpebrae, money)

/nde0 of images 

he eye is a sensory organ responsible for vision. /t can be divided into three tunics that surround

fluid-filled spaces. hese tunics are the corneosclera, uvea, and retina. he fluid-filled spaces

include the anterior and posterior chambers and the vitreous body, the latter being a gelatinousmass. he corneosclera or outermost coat is divided into the cornea and sclera. he sclera is

composed primarily of a collagen coat that is opaue and covers the posterior '!2s of the eye.

he cornea covers the anterior 1! of the eye is speciali%ed for light transmission. /n this regionof the eye, the coat is translucent due to its lac of vasculature and the organi%ation of the

collagen stroma. he middle coat or uvea can be subdivided into " parts: the choroid (posterior),

ciliary body (anterior), and iris (most anterior). he choroid is the largest component of the uveaand it covers the posterior !"rds of the eye. /t can be divided into four layers: the

suprachoroidal layer, vascular (vessel) layer, choroidocapillary layer, and 3ruch2s membrane

(basal comple0). he vascular layer contains arteries, veins, and pigmented melanocytes. hechoriodocapillary layer contains the capillaries and 3ruch2s membrane is essentially a thic basal

lamina that separates the choroid from the retina. he ciliary body and iris are in the anterioraspect of the eye. he ciliary body functions to produce the aueous humor of the posterior and

anterior chamber and contains a smooth muscle mass involved in regulating lens thicness(focusing the image). he lens of the eye is suspended by very thin ligaments that attach to the

ciliary processes, and the thicness of the lens is modulated by smooth muscle $ithin the ciliary

 body. he iris covers the lens and regulates the amount of light entering the orbit through the pupil. he space bet$een the lens and the iris is called the posterior chamber into $hich aueous

7/17/2019 ANAT D502

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humor from the ciliary body is secreted. he space bet$een the iris and the cornea is called the

anterior chamber.

he last, most interior tunic of the eye is the retina. 4ithin this tunic there are several cell(nuclei) layers. he outermost, adjacent to 3ruch2s membrane of the choroid, is a single

 pigmented cell layer containing melanocytes. he ne0t layer is the photosensitive layercontaining the rod and cone cells responsible for transduction of photons (light intensity for rods

and light color for cones) into sensory input. his is follo$ed by the bipolar then ganglion celllayer. hese latter cells establish synapses $ith the photosensitive cells and integrate the visual

input. he ganglion cell a0ons join and form the optic nerve that e0its the eye in your blind spot

(optic dis or optic nerve papilla). he photosensitive retinal epithelia covers the posterior !"rdsof the orbit and is not uniform in all areas. 5t the optic disl there are no photosensitive cells, only

a0ons of the ganglion cells. his region is off the optical a0is and is your blind spot. 5t the

optical a0is the retina is thinner as the bipolar and ganglion cell nuclei are absent and this regioncontains primarily cone cells. his is the region of the retina that has the greatest visual accuracy.

5t the anterior aspect of the retina, the light-sensitive neural tissue (photosensitive cells, bipolar,

and ganglion cells) is lost and this transition %one is called the ora serrata (appears serrated lie astea nife). 4ithin the retina and uvea, there are pigmented cells $hose function is to absorb

light and prevent light scattering $ithin the orbit to enhance visual acuity. 6nlie integument, the

 pigment remains in the melanocytes instead of being taen up by surrounding cells.

he eye is covered by the eyelid $hich affords both mechanical and chemical protection of theeye. 4ithin the eyelid is a modified sebaceous gland called the tarsal (7eibomian) gland $hich

secretes the lipid component of tear film.

4e $ill first study the eyelid (s+). 0amine the lid at lo$ po$er and e0amine the bulbous

region of the lid $ith its eyelashes. 3ehind the eyelashes and near the internal aspect (peeper

side) of the lid is an alveolar gland. his is the tarsal gland $hich is a modified sebaceous glandthat does not secrete onto the lashes but rather releases it greasy product at the margins of the

eyelids onto the conjunctiva. he secretory alveoli connect via short ducts to a long e0cretoryduct that is lined $ith stratified suamous epithelia. he tarsal gland and its duct run nearly the

full length of the palpebra in and inferior - superior orientation $ithin the tarsal plate (see belo$)

and thus the name tarsal gland. /f you migrate further up the lid you $ill note essentially &

layers: thin sin covering the outer aspect, a layer of seletal muscle (orbicularis oculi), a plate of fibroelastic connective tissue called the tarsal plate, and the inner layer ne0t to the eye $hich is

the conjunctiva. he tarsal plate is relatively rigid and made of dense irregular collagenous

connective tissue and elastic connective tissue. /n particularly gifted people, the palpebra can beeverted sho$ing the palpebra conjunctival epithelia (inner aspect of lid) and the rigidity of the

tarsal plate holds the palpebra in this position. he palpebra conjunctiva rests upon the tarsal

 plate and its epithelia is stratified $ith goblet cells $hile its lamina propria (subconjunctivallayer) is highly vasculari%ed.

8ets open the lid and study the peeper (s+&). 9or the lined images, the photons are passing from

left to right . 5lso, reali%e that the eye is a sphere and not all sections are going to sho$ all the

features of the eye to good advantage (/ used & different sections for the lined images). 4e $illvie$ the features of the eye as light $ould progress through it. 8oo at the section of the eye

7/17/2019 ANAT D502

http://slidepdf.com/reader/full/anat-d502 7/13

$ith your naed eye. he most obvious structure that you $ill note is the lens as it is a large

eosinophilic disc at the anterior aspect of the eye. 7ore anterior to that is a space follo$ed by a

layer of avascular tissue. his layer is the cornea. here are ' layers to the cornea and startingfrom the outside, the layers are: the corneal epithelium (stratified suamous epithelia), 3o$man2s

membrane upon $hich the corneal epithelium rests, corneal stroma (dense regular collagenous

connective tissue $ith fibroblasts), Descemet2s membrane and the corneal endothelium (simplelo$ cuboidal epithelia) that rests upon Descemet2s membrane. he corneal endothelium faces a

space that is the anterior chamber of the peeper. 9ollo$ the cornea to its margin $here it joins the

sclera (corneoscleral junction or limbus) and you $ill note a change in the epithelia andunderlying tissue as it changes into the bulbar conjunctiva. rogress into the deep stroma of the

sclera at the limbus and you $ill note a canal $ithin the sclera and a mesh$or of smaller

openings in direct communication $ith the anterior chamber. he larger lumen $ithin the stroma

of the sclera is the canal of *chlemm $hile the smaller openings in direct communication $iththe anterior chamber is called the trabecular mesh$or (spaces of 9ontana). hese spaces and the

canal form the outflo$ path for aueous humor out of the anterior chamber and eventually into

the venous system.

he ne0t most obvious structure that projects into the anterior chamber near the trabecular

mesh$or and canal of *chlemm is the iris. /t is a projection arising from the anterior region of

the ciliary body. he iris projects over the lens and its interior margin defines the pupil and the

iris in toto defines the anterior chamber from the posterior chamber. ;ear the pupil, the iriscontains a loose, vascular connective tissue stroma $ith interspersed melanocytes, follo$ed by

an eosinophilic layer made of smooth muscle and lastly, a highly pigmented layers pro0imal to

the lens. he eosinophilic layer is made of circularly arranged smooth muscle and is called thesphincter pupillae muscle. /ts contraction decreases pupil diameter. 5s you progress to the base

of the iris (to$ard the *chlemmer), the sphincter pupillae muscle stops and a very thin

eosinophilic layer is noted that rests upon the highly pigmented layer   pro0imal to the pupil. his

eosinophilic layer is called the dilator pupillae muscle. /t represents the radially arrangedmuscular processes of the myoepithelial anterior epithelium. /ts contraction opens (dilates) the

 pupil. hus, these <muscles< are involved in controlling pupil diameter and thus the amount of

light that passes into the lens.

he lens is an avascular structure just posterior to the iris. he lens is encased $ithin a capsule

(lens capsule) and beneath this capsule and on the e0terior aspect is a single layer of cuboidal

cells called the subcapsular epithelium. he capsule is a thic basement membrane produced bythe subcapsular epithelium. 3eneath the epithelium and maing the main body of the lens are the

lens fibers $hich are enucleated cells. hese cells are full of crystallins. 5t the euator (midline)

and near the periphery of the lens, you $ill observe nuclei $ithin the body of the lens and these

are cells derived from the subcapsular epithelium that are giving rise to the mature lens fibers(nascent lens fiber cells). /n this region, you $ill also note thin fibers that connect to the lens

capsule. hese fibers are called %onular fibers and connect the lens to the ciliary processes that

 project from the ciliary body. hese fibers are o0ytalin fibers made by the ciliary body epithelia.=ontraction of the ciliary muscles (to$ards the anterior aspect of the eye) rela0es the tension on

the %onular fibers allo$ing the lens to rela0 (become thicer).

7/17/2019 ANAT D502

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he ciliary body is a thicening of the anterior aspect of the uvea. he main mass of the ciliary

 body is formed by its stroma $hich contains vasculature and melanocytes and a large mass of

smooth muscle, the ciliary muscle. he epithelium of the ciliary body is bi-laminar and it produces the aueous humor and releases it into the posterior chamber> it also produces the

%onular fibers that anchor the lens. he outer pigmented layer of the epithelium is continuous

$ith the pigmented layer of the retina (retinal pigmented epithelium).

9ollo$ along the epithelia along the lateral $all from the ciliary body to the posterior aspect ofthe eye and you $ill note a change in the epithelia $here it thicens and sho$s obvious lamina

of nuclei. his region is called the ora serrata is the anterior most aspect of the neural retina

(photosensitivity starts here). 4hen vie$ed from the inside out, this junction is serrated (lie astea nife at *t. lmo2s), hence the name. 5s you progress to the posterior aspect of the eye, you

$ill note that the epithelia thicens and is typically thicest at the most posterior aspect of the

eye. 0amine the layers of the eye in this region. he inner most layer is the retina $hich can besubdivided into the neural retina (photosensitive cells and relay neurons) and the retinal pigment

epithelium (pigmented cells). he neural retina has three lamina of nuclei $ith essentially nerve

cell processes filling the space bet$een the nuclear lamina. he light first passes through theganglion cell layer , then through the bipolar cell layer (inner nuclear layer), and lastly to the

 photoreceptor cell layer (outer nuclear layer).  /n terms of trendy terminology, these cells e0press

the photosome (proteins involved in transduction of light to an electrical signal). he light then

hits the outer segment of the rods and cones that contains the photoreceptors of the cells. /f thelight is not absorbed by the photoreceptors it is absorbed by the pigmented retinal epithelial cells

that define the posterior most aspect of the retina proper. hese cells form a single layer of nuclei

that rests upon 3ruch2s membrane of the choroid region of the uvea. he choroid is characteri%ed by its vascularity and presence of pigmented cells $ithin the stroma. he outermost aspect or

layer of the eye is the sclera $ith its fibrous stroma made of dense collagenous connective tissue

$ith interspersed fibroblasts.

*ome features of the retina $hich may not be readily apparent in your section includes thevasculature of the retina, the fovea and the optic dis. 0amine the retina and you may observe

some capillaries $ithin the ganglion cell layer . hese capillaries can be visuali%ed $ith an

ophthalmoscope, and they nourish the retina. 0amine the retina in the posterior aspect of theorbit and you may o bserve a thinning of the ganglion cell layer , if so, you are near the fovea. /f

you are at the fovea, only one cell nuclei layer $ould be present and it $ould be that of the

 photoreceptor cell nuclei. *ome$hat off the center of the optical a0is in the posterior orbit, youmay observe a region in $hich the retina is devoid of neural retina nuclei. his is the optic dis

(papilla) in $hich the ganglion cells a0ons join, e0it the orbit and form the optic nerve.

?opefully, you have enjoyed this visual tour of the cellular features of the orbit.

5nat D'@ - Dasar ?istologi

ye ra-lab

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direvisi 11!1+!@

ujuan:

1. Aelasan strutur elopa mata dan yang terait, non-yg menutupi (mata spesifi) elenjar.

. Aelasan ! diagram jalan cahaya melalui mata.

". ahu organisasi strutural mata. 7enetapan " lapisan ! tuni dari mata dan strutur yang

 berbeda di dalam mantel.

&. Aelasan strutural ! fungsional organisasi dari iris.

'. Define ! mengidentifiasi berbagai lapisan retina.

. Aelasan aliran cairan di dalam bili anterior posterior dan mata.

*lide:

s+& ye (orbit atau pengintip, monyet)s+ yelid (palpebrae, monyet)

/nde0 gambar

7ata adalah organ yang bertanggung ja$ab untu indra penglihatan. Dapat dibagi menjadi tiga

tuni yang mengelilingi ruang berisi cairan. uni ini adalah corneosclera, uvea, dan retina.

3erisi cairan ruang termasu anterior dan posterior vitreous ruang dan tubuh, yang terahirmenjadi agar-agar massa. he corneosclera atau mantel terluar dibagi e dalam ornea dan

sclera. he sclera adalah terutama terdiri dari lapisan olagen yang buram dan mencaup

 posterior ' ! 2s dari mata. #ornea mencaup anterior 1 ! dari mata adalah husus untutransmisi cahaya. Di $ilayah ini dari mata, mantel adalah tembus arena urangnya pembuluh

darah dan organisasi dari olagen stroma. 7antel atau tengah uvea dapat dibagi menjadi "

 bagian: choroid (posterior), ciliary body (anterior), dan iris (paling anterior). he choroid adalahomponen terbesar dan uvea mencaup !"rds posterior mata. Dapat dibagi menjadi empat

lapisan, yaitu lapisan suprachoroidal, vasular (pembuluh) lapisan, lapisan choroidocapillary,

dan 3ruch2s membran (basal omples). 8apisan vasular berisi arteri, vena, dan pigmen

melanosit. 8apisan yang berisi choriodocapillary apiler dan membran 3ruch yang padadasarnya adalah lamina basal tebal yang memisahan choroid dari retina. he ciliary tubuh dan

iris berada dalam aspe anterior mata. Bang ciliary fungsi tubuh untu menghasilan humor

 berair dan anterior posterior ruang dan berisi massa otot polos yang terlibat dalam pengaturanetebalan lensa (fous gambar). 8ensa mata tergantung oleh ligamen sangat tipis yang meleat

 pada proses ciliary, dan etebalan lensa diatur oleh otot polos di dalam tubuh ciliary. 7encaup

iris lensa dan mengatur jumlah cahaya yang memasui orbit melalui murid. Cuang antara lensadan iris disebut posterior chamber e yang berair humor dari tubuh ciliary diseresi. Cuang

antara iris dan ornea disebut anterior chamber.

erahir, sebagian besar interior tuni dari mata adalah retina. Dalam tuni ini ada beberapa sel

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(nuleus) lapisan. erluar, berbatasan dengan 3ruch2s membran choroid, adalah satu lapisan sel

 pigmen yang mengandung melanosit. 8apisan beriutnya adalah lapisan fotosensitif yang

mengandung sel batang dan erucut yang bertanggung ja$ab untu transdusi foton (intensitascahaya untu batang dan cahaya $arna untu erucut) e input sensoris. /ni diiuti oleh bipolar

maa lapisan sel ganglion. *el terahir ini membentu sinapsis dengan sel-sel fotosensitif dan

mengintegrasian input visual. *el ganglion ason yang bergabung dan membentu saraf optiyang eluar dari mata di blind spot (opti dis atau saraf opti papila). pitel retina yang

fotosensitif meliputi !"rds posterior dari orbit dan tida seragam di semua daerah. ada disl

opti tida ada fotosensitif sel, hanya ason dari sel ganglion. 4ilayah ini dari sumbu opti danelemahan 5nda. ada sumbu opti retina lebih tipis sebagai bipolar dan sel ganglion inti yang

absen dan daerah ini terutama mengandung sel-sel erucut. /ni adalah daerah retina yang

memilii aurasi visual terbesar. ada aspe anterior retina, saraf yang sensitif terhadap cahaya

 jaringan (sel fotosensitif, bipolar, dan sel-sel ganglion) yang hilang dan %ona transisi ini disebutora serrata (muncul bergerigi seperti pisau stea). Dalam retina dan uvea, ada sel-sel berpigmen

yang berfungsi untu menyerap cahaya dan mencegah hamburan cahaya dalam orbit untu

meningatan etajaman visual. ida seperti lapisan atas, pigmen tetap dalam melanosit

 buannya diambil oleh sel-sel di seitarnya.

7ata tertutup oleh elopa mata yang memberian bai meani dan imia perlindungan mata.Dalam elopa mata adalah elenjar sebasea yang dimodifiasi disebut tarsal (7eibomian)

elenjar yang mengeluaran omponen lipid film air mata.

#ami aan studi pertama elopa mata (s+). erisa tutup pada daya rendah dan memerisa

daerah bulat dengan bulu mata tutup. Di bali bulu mata dan deat aspe internal (pengintip sisi)

dari tutup adalah elenjar alveolar. /ni adalah elenjar tarsal yang merupaan diubah sebaceous

elenjar yang tida mengeluaran bulu mata e rilis itu melainan produ berminya di pinggirelopa mata e onjungtiva. 5lveoli seretoris onesi melalui saluran pende untu

esretoris panjang saluran yang dilapisi dengan epitel suamosa berlapis. #elenjar yang tarsal

dan menjalanan hampir dutus panjang penuh di palpebra dan inferior - superior orientasidalam piring tarsal (lihat di ba$ah) dan dengan demiian nama elenjar tarsal. Aia 5nda

 bermigrasi lebih lanjut tutup catatan 5nda pada dasarnya & lapisan: ulit tipis yang meliputi

aspe luar, lapisan otot ranga (orbicularis oculi), sepiring fibroelastic jaringan iat disebut tarsal plate, dan lapisan sebelah mata yang merupaan onjungtiva. arsal plate yang relatif au dan

terbuat dari padat tida teratur collagenous jaringan iat dan jaringan iat elastis. Dalam berbaat

hususnya orang, palpebra dapat everted menunjuan palpebra conjunctival epitel (aspe batin

tutup) dan eauan dari lempeng tarsal memegang palpebra dalam posisi ini. #onjungtiva palpebra terleta di atas piring dan tarsal epitel adalah berlapis dengan sel piala sementara lamina

 propria (subconjunctival lapisan) sangat vasculari%ed.

7ari membua tutup dan mempelajari pengintip (s+&). 6ntu terhubung gambar, foton yang

le$at dari iri e anan. *elain itu, menyadari bah$a mata adalah bola dan tida semua bagian

aan menampilan semua fitur mata euntungan yang bai (saya menggunaan & bagian yang berbeda untu gambar yang terhubung). #ita aan melihat ciri-ciri sebagai cahaya mata aan

emajuan melalui itu. 8ihatlah bagian mata dengan mata telanjang. *trutur yang paling jelas

 bah$a 5nda aan diperhatian adalah lensa arena merupaan dis eosinofili besar pada aspe

anterior mata. 8ebih anterior untu itu adalah sebuah ruang diiuti oleh lapisan jaringan

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avascular. 8apisan ini adalah ornea. 5da ' lapisan e ornea dan mulai dari luar, lapisan adalah:

epitel ornea (epitel suamosa berlapis), membran 3o$man yang di atasnya terleta epitel

ornea, ornea stroma (collagenous biasa padat dengan fibroblas jaringan iat), Descemet2smembran dan pada endotelium ornea (epitel cuboidal rendah sederhana) yang terleta pada

Descemet2s membran. ndotelium ornea $ajah-$ajah di ruang yang merupaan ruang anterior

dari pengintip. /uti ornea e margin di mana bergabung dengan sclera (corneoscleral junctionatau limbus) dan 5nda aan mencatat perubahan dalam epitel dan jaringan yang mendasarinya

seperti perubahan e onjungtiva yg berhubungan dgn benga. #emajuan e dalam stroma dari

sclera di limbus dan 5nda aan melihat sebuah anal dalam sclera dan mesh$or buaan yanglebih ecil dalam omuniasi langsung dengan ruang anterior. *emain besar lumen dalam

stroma dari sclera adalah saluran *chlemm sedangan buaan yang lebih ecil dalam omuniasi

langsung dengan ruang anterior disebut trabecular mesh$or (ruang 9ontana). /ni ruang dan

 bentu anal arus eluar jalan bagi humor berair eluar dari ruang anterior dan ahirnya edalam sistem vena.

3eriutnya strutur yang paling jelas proye e ruang anterior deat trabecular mesh$or dan

saluran *chlemm adalah iris. /ni adalah sebuah proyesi yang timbul dari daerah anterior tubuhciliary. roye iris di atas lensa dan bagian dalamnya margin mendefinisian murid dan iris

dalam mendefinisian toto anterior posterior ruang dari amar. Deat murid, iris berisi longgar, pembuluh darah jaringan iat stroma dengan diselingi melanosit, diiuti oleh lapisan eosinofili

terbuat dari otot polos dan terahir, yang sangat pigmented prosimal lapisan lensa. osinofili

lapisan yang terbuat dari otot polos siruler diatur dan disebut pupillae sfingter otot. /ts diametermurid ontrasi menurun. #etia 5nda maju e bagian ba$ah iris (e arah *chlemmer), otot

sfingter pupillae berhenti dan sangat tipis lapisan eosinofili dicatat bah$a terleta pada lapisan

yang sangat pigmented prosimal e murid. 8apisan eosinofili ini disebut pupillae otot dilator.

/ni me$aili radial otot mengatur proses dari anterior myoepithelial epitel. /ts ontrasimembua (dilates) murid. Dengan demiian, ini <otot< yang terlibat dalam mengendalian murid

diameter dan dengan demiian jumlah cahaya yang masu e dalam lensa.

8ensa adalah strutur avascular hanya posterior iris. 8ensa terbungus dalam apsul (apsul

lensa) dan di ba$ah apsul ini dan pada aspe esterior satu lapisan sel cuboidal disebut epitel

subcapsular. #apsul adalah tebal membran basal yang diprodusi oleh epitel subcapsular. Di ba$ah epitel dan membuat tubuh utama lensa adalah lensa yang enucleated serat sel. *el-sel ini

 penuh dengan crystallins. Di euator (garis tengah) dan di deat pinggiran lensa, 5nda aan

melihat inti dalam tubuh dari lensa dan sel-sel ini berasal dari epitel subcapsular yang

menimbulan serat lensa de$asa (baru lahir sel serat lensa). Di $ilayah ini, 5nda juga aanmencatat serat tipis yang menghubungan e apsul lensa. *erat ini disebut serat dan

menghubungan %onular lensa e proses yang ciliary proye dari tubuh ciliary. O0ytalin serat ini

serat dibuat oleh tubuh ciliary epitel. #ontrasi otot ciliary (terhadap aspe anterior mata)menenangan etegangan pada serat %onular memunginan lensa untu bersantai (menjadi

lebih tebal).

he ciliary tubuh adalah penebalan anterior aspe uvea. 7assa utama dari tubuh ciliary terbentu 

oleh stroma yang mengandung pembuluh darah dan melanosit dan massa besar otot polos, otot

yang ciliary. pitel tubuh ciliary bi-laminar dan menghasilan humor yang berair dan

melepasan e ruang posterior, tetapi juga menghasilan serat yang %onular jangar lensa.

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3erpigmen luar lapisan epitel adalah terus-menerus dengan lapisan berpigmen retina (retinal

 pigmen epitel).

/uti sepanjang epitel sepanjang dinding lateral dari tubuh ciliary aspe posterior mata dan 5nda

aan mencatat perubahan pada epitel mana mengental dan jelas menunjuan lamina dari inti.

4ilayah ini disebut ora serrata adalah aspe yang paling anterior saraf retina (photosensitivitydimulai di sini). 3ila dilihat dari dalam e luar, ini adalah sambungan bergerigi (seperti pisau

stea di *t lmo2s), maa nama itu. #etia 5nda maju e aspe posterior mata, 5nda aan

 perhatian bah$a epitel mengental dan biasanya tebal pada aspe yang paling posterior mata.erisa lapisan mata di $ilayah ini. 3atin paling lapisan retina yang dapat dibagi e dalam saraf

retina (sel fotosensitif dan relay neuron) dan epitel pigmen retina (sel berpigmen). *araf retina

memilii tiga lamina dari inti dengan proses sel saraf dasarnya mengisi ruang antara lamina

nulir. =ahaya pertama mele$ati sel ganglion lapisan, emudian melalui lapisan sel bipolar(dalam lapisan nulir), dan terahir e lapisan sel photoreceptor (luar lapisan nulir). Dalam hal

trendi terminologi, sel-sel ini mengungapan photosome (protein yang terlibat dalam transdusi

cahaya e sinyal listri). =ahaya emudian hits segmen luar batang dan erucut yang

mengandung sel fotoreseptor. Aia lampu tida diserap oleh fotoreseptor itu diserap oleh sel-selepitel pigmen retina yang mendefinisian aspe paling posterior retina yang tepat. *el-sel ini

membentu satu lapisan inti yang terleta pada membran 3ruch2s choroid dari daerah uvea. Bangchoroid dicirian oleh vascularity dan ehadiran sel-sel pigmen di dalam stroma. erluar aspe

atau lapisan sclera mata adalah dengan stroma fibrosa padat collagenous terbuat dari jaringan

iat dengan diselingi fibroblas.

3eberapa fitur dari retina yang mungin tida mudah terlihat pada bagian 5nda termasu

 pembuluh darah retina, yang fovea dan opti dis. 7emerisa retina dan 5nda mungin

mengamati beberapa apiler di dalam lapisan sel ganglion. #apiler ini dapat dilihat denganophthalmoscope, dan merea memberi maan retina. 7emerisa retina dalam aspe posterior

orbit dan 5nda mungin mengamati penipisan lapisan sel ganglion, jia demiian, 5nda deat

fovea. Aia 5nda berada di fovea, hanya satu sel lapisan inti aan hadir dan aan photoreceptor bah$a dari inti sel. 5ga dari pusat sumbu opti di posterior orbit, 5nda dapat mengamati

a$asan di mana retina adalah saraf retina tanpa inti. /ni adalah dis opti (papila) di mana sel-

sel ganglion ason bergabung, eluar dari orbit dan membentu saraf opti.

7udah-mudahan, 5nda telah menimati tur visual ini fitur selular orbit.

*umbangan terjemahan yang lebih bai 

5friaans sti Aepang 7alta Cusia uri

id UTF-8 ANAT D502 - Ba en|id Anat D502 - Das

 Anat

D502 - Dasar Histologi <br> <br 

<br> <br>direvisi 111!08 <br>

<br>1" #elas$an str%$t%r $elo&a$

'iri(

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