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http://en.wikipedia.org/wiki/Tenon's_capsule

Tenon's capsuleFrom Wikipedia, the free encyclopedia

Tenon' s capsule

The right eye in sagittal section, showing the fascia bulbi

(semidiagrammatic).

Latin vagina bulbi

Gray's subject #227 1024

The fascia bulbi(also known as the capsule of Tnonand the bulbar sheath) is a thin membrane which

envelops the eyeball from theoptic nerveto thelimbus, separating it from the orbital fat and forming a

socket in which it moves.

Its inner surface is smooth, and is separated from the outer surface of thescleraby theperiscleral lymph

space.

This lymph space is continuous with thesubduralandsubarachnoidcavities, and is traversed by delicate

bands of connective tissue which extend between the fascia and the sclera.

The fascia is perforated behind by the ciliary vessels and nerves, and fuses with the sheath of the optic

nerve and with the sclera around the entrance of theoptic nerve.

In front it adheres to theconjunctiva,and both structures are attached to the ciliary region of the eyeball.

The structure was named afterJacques-Ren Tenon(17241816),[1]

a French surgeon and pathologist.

Contents
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[hide]

1 Relations to extraocular muscles

2 Sub Tenon's block for ophthalmic surgery

3 Pathology

4 References

Relations to extraocular muscles[edit]

It is perforated by the tendons of the ocular muscles, and is reflected backward on each as a tubular

sheath.

The sheath of theObliquus superioris carried as far as the fibrous pulley of that muscle; that on

theObliquus inferiorreaches as far as the floor of the orbit, to which it gives off a slip.

The sheaths on the recti are gradually lost in theperimysium,but they give off important expansions.

The expansion from theRectus superiorblends with the tendon of theLevator palpebrae; that of

theRectus inferioris attached to theinferior tarsus.

The expansions from the sheaths of theRecti lateralisandmedialisare strong, especially that from the

latter muscle, and are attached to the zygomatic bone and lacrimal bone respectively.

As they probably check the actions of these two Recti they have been named the medial and lateral check

ligaments.

Charles Barrett Lockwooddescribed a thickening of the lower part of the fascia bulbi, which he named the

'suspensory ligament of the eye'. It is slung like a hammock below the eyeball, being expanded in the

center, and narrow at its extremities which are attached to the zygomatic andlacrimal bonesrespectively.

Sub Tenon's block for ophthalmic surgery[edit]

Local anaesthetic may be instilled into the space between Tenon's capsule and the sclera to provide

anaesthesia for eye surgery, principally cataract surgery. After applying local anaesthetic drops to

anaesthetise theconjunctiva,a small fold of conjunctiva is lifted off the eyeball and an incision made. A

blunt, curved cannula is passed through the incision into theperiscleral lymph spaceand a volume oflocal

anaestheticsolution is instilled. The advantages are a reduced risk of bleeding and of penetration of the

globe, compared toperibulbarandretrobulbarapproaches. Akinesia (paralysis of the external eye

muscles) may be less complete, however.

Pathology[edit]

Main article:Tenonitis

Tenon's capsule may be affected by a disease called idiopathic orbital inflammation, a condition of

unknown etiology that is characterized by inflammation of one or more layers of the eye. The disease is
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e=Tenon%27s_capsule&action=edit&section=1http://en.wikipedia.org/wiki/Tenon's_capsule#Referenceshttp://en.wikipedia.org/wiki/Tenon's_capsule#Pathologyhttp://en.wikipedia.org/wiki/Tenon's_capsule#Sub_Tenon.27s_block_for_ophthalmic_surgeryhttp://en.wikipedia.org/wiki/Tenon's_capsule#Relations_to_extraocular_muscleshttp://en.wikipedia.org/wiki/Tenon's_capsule


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also known as orbital inflammatory pseudotumor, and sometimes may only affect thelacrimal glandor

theextraocular muscles.[2]

References[edit]

1. ^Tenon JR, Naus J, Blanken R (March 2003). "Anatomical observations on some parts of the eye and

eyelids. 1805". Strabismus11(1): 638.doi:10.1076/stra.11.1.63.14089.PMID12789585.

2. ^Mitchell, Richard N. "Eye, Orbit". P
http://en.wikipedia.org/wiki/Lacrimal_glandhttp://en.wikipedia.org/wiki/Lacrimal_glandhttp://en.wikipedia.org/wiki/Lacrimal_glandhttp://en.wikipedia.org/wiki/Extraocular_muscleshttp://en.wikipedia.org/wiki/Extraocular_muscleshttp://en.wikipedia.org/wiki/Tenon's_capsule#cite_note-Robbins-2http://en.wikipedia.org/wiki/Tenon's_capsule#cite_note-Robbins-2http://en.wikipedia.org/wiki/Tenon's_capsule#cite_note-Robbins-2http://en.wikipedia.org/w/index.php?title=Tenon%27s_capsule&action=edit&section=4http://en.wikipedia.org/w/index.php?title=Tenon%27s_capsule&action=edit&section=4http://en.wikipedia.org/w/index.php?title=Tenon%27s_capsule&action=edit&section=4http://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-pmid12789585_1-0http://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-pmid12789585_1-0http://en.wikipedia.org/wiki/Digital_object_identifierhttp://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1076%2Fstra.11.1.63.14089http://dx.doi.org/10.1076%2Fstra.11.1.63.14089http://dx.doi.org/10.1076%2Fstra.11.1.63.14089http://en.wikipedia.org/wiki/PubMed_Identifierhttp://en.wikipedia.org/wiki/PubMed_Identifierhttp://www.ncbi.nlm.nih.gov/pubmed/12789585http://www.ncbi.nlm.nih.gov/pubmed/12789585http://www.ncbi.nlm.nih.gov/pubmed/12789585http://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-Robbins_2-0http://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-Robbins_2-0http://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-Robbins_2-0http://www.ncbi.nlm.nih.gov/pubmed/12789585http://en.wikipedia.org/wiki/PubMed_Identifierhttp://dx.doi.org/10.1076%2Fstra.11.1.63.14089http://en.wikipedia.org/wiki/Digital_object_identifierhttp://en.wikipedia.org/wiki/Tenon's_capsule#cite_ref-pmid12789585_1-0http://en.wikipedia.org/w/index.php?title=Tenon%27s_capsule&action=edit&section=4http://en.wikipedia.org/wiki/Tenon's_capsule#cite_note-Robbins-2http://en.wikipedia.org/wiki/Extraocular_muscleshttp://en.wikipedia.org/wiki/Lacrimal_gland


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http://telemedicine.orbis.org/bins/volume_page.asp?cid=1-2161-2163-2172

Chapter 2: Surgical Anatomy-

Tenons capsuleLecture 8 of 22 NEXT

Tenon's capsule is a structure with definite body and substance in childhood which

gradually atrophies in old age but not to the same degree as conjunctiva. Tenon's

capsule has an anterior and posterior part. Anterior Tenon's capsule is the vestigial

capsulopalpebral head of the rectus muscles. This covers the anterior half to two-thirds

of the rectus muscles in their sheaths as well as the intermuscular membrane. Anterior

Tenon's capsule is fused with the undersurface of conjunctiva and attaches to sclera at

the limbus. The fused conjunctiva-anterior Tenon's capsule is movable over underlying

posterior Tenon's capsule and episclera, the latter being the anterior extension of

posterior Tenon's capsule. Episclera starts at the level of the insertion of the rectus

muscles in a line around the globe, which is called the spiral of Tillaux. Episclera joinsconjunctiva and anterior Tenon's capsule, fusing at the limbus.

Posterior Tenon's capsule is made up of the fibrous sheath of the rectus muscles

together with the intermuscular membrane. According to Lester Jones, the tissues that

make up posterior Tenon's capsule form at a later evolutionary stage than those forming

anterior Tenon's capsule. Fibrous attachments between the inner surface of anterior

Tenon's capsule and the outer muscle sheath (part of posterior Tenon's capsule) fuse at

a point 15 to 20 mm behind the insertion of the medial and lateral rectus muscles to

form a barrier to extraconal fat. A condensation of fibrous tissue and smooth muscle

between the outer surface of anterior Tenon's capsule and the orbital wall medially and

laterally is the location of the aforementioned pulleys of the horizontal rectus muscles. Ifthe horizontal rectus muscle is separated completely from anterior Tenon's capsule,

exposing extraconal fat, there will be no or reduced pulley effect on the eye muscle. This

will result in up and down slip of the muscle relative to the globe. It is not practical or

even logical in the usual strabismus surgery to free pulleys outside anterior Tenon's

capsule, but this could be done for special need. Eye muscle surgery is routinely

performed entirely insideanterior Tenon's capsule with no fat exposure (Figure 25 A-C).

Figure 25The Conjunctiva/Tenons Capsule Relationships
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AAxial view of the orbit

1 Wall of the orbit

2 Conjunctiva3 Anterior Tenons capsule

4 Posterior Tenons capsule

5 The muscle

6 Intermuscular membrane

(posterior Tenons capsule)

7 Intraconal orbital fat

8 Extraconal orbital fat

9 Horizontal pulley

10 Episclera

B1 The limbal fusion of theconjunctiva and anterior

Tenons capsule2 Potential space between

anteriorTenons capsule and episclera3 The muscle in its sheath(posterior Tenons capsule)inserting into the sclera

4 Postinsertional musclefootplates

5 Episclera6 Conjunctiva7 Anterior Tenons capsule

CCoronal section of B at X

1 Conjunctiva

2 Anterior Tenons capsule3 Muscle sheath

4 Extraocular muscle

5 Intermuscular membrane

6 Sclera substance

Posterior Tenon's capsule, composed of the muscle's capsule and the intermuscular

membrane, unites the rectus muscles in a ring around the globe. The extent to which the

intermuscular membrane is cut during surgery influences how far the rectus muscles,

particularly the medial and to some extent the lateral, will retract during surgery.

Dissection of posterior Tenon's capsule far posteriorly leads to exposure of intraconal fat,

so called because it resides inside the muscle cone. Excessive dissection of anterior

Tenon's capsule exposes extraconal fat and risks disruption of the pulleys of the medial

and lateral rectus muscles.

Figure 26

A


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B

C

AWhen the layer of fused

conjunctiva-anterior Tenon's

capsule is retracted, the muscle

insertion in its sheath is exposed.

Fibrous attachments are seenbetween the undersurface of

anterior Tenons capsule and the

outer surface of the muscle. The

fusion of the intermuscular

membrane (posterior Tenon's

capsule), as well as of the muscle to

the sclera, is apparent. This fusion

of the intermuscular membrane to

the sclera must be incised before

the bare sclera and subposterior

Tenon's capsule space can beencountered. Only after entering

subposterior Tenon's capsule space

can the insertion of the rectus

muscle be engaged cleanly on a

muscle hook. This is the free space

used by the retina surgeon. The tip

of the scissors in the photo points

to this free space.

BPosterior Tenons capsule attaches to sclera at the muscles

insertion and in the intermuscular space forming the spiral of

Tillaux.

CThe muscle hook is placed in a hole created in intermuscular

membrane adjacent to the muscle insertion and glides along bare

sclera behind the rectus muscle insertion and is exposed at theopposite muscle border with a snip incision.

DThe muscle hook is placed in a hole created in intermuscular membrane adjacent to the muscle insertion and

glides along bare sclera behind the rectus muscle insertion and is exposed at the opposite muscle border with a

snip incision.With a limbal incision, the multiple layers and surfaces associated with the rectus muscles can be

readily seen. Conjunctiva and anterior Tenons capsule shown here separated are actually fused and separated

only with difficulty.


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While extraocular muscle surgery is performed beneath anterior Tenon's capsule, it is done within the plane of

posterior Tenon's capsule. The intermuscular membrane part of posterior Tenon's capsule must be fenestrated in

order to place a muscle hook behind the insertion of a rectus muscle (Figure 26 A-D). How much more

dissection is done in the intermuscular membrane beyond the minimum required to gain access to the muscle is

the decision of the surgeon. It is probably wise to do as little cutting of posterior Tenon's capsule as is

compatible with the conduct of the surgical procedure intended. Retinal detachment surgery, in contrast to

extraocular muscle surgery, is carried out beneathposterior Tenon's capsule. This enables a view of the scleral

surface far posteriorly to a point near the posterior ciliary vessels and the optic nerve.

Surgical anatomy of the rectus musclesLecture 9 of 22 NEXT

Each rectus muscle inserts at a different distance from the limbus. The insertions of

these muscles are the prime surgical landmarks in extraocular muscle surgery. The

medial rectus is said to insert in the normal eye 5.5 mm from the limbus. This figure

presumably was arrived at from study of otherwise normal eyes. Since no specific

mention is made of whether the measurements were taken from specimens with

strabismus, it is assumed they were not. The average distance between the limbus and

the medial rectus insertion of 112 medial rectus muscles in 66 esotropic patients was 4.4

mm with a range of 3.0 to 6.0 mm. Eight patients had unequal medial rectus insertion to

limbus measurements. There was no correlation found between the angle of

esodeviation and the distance of the medial rectus insertion from the limbus. The

variability of this insertion along with its lack of correlation with the angle of esotropia

begs the question, Is the insertion the best landmark for measurement of a medial

rectus recession? Since the answer is obviously no, it is preferable to use the limbus, a

more consistent anatomical point, as the reference for recession of the medial rectus

muscle. When measuring from the limbus, the amount of muscle retroplacement from

the muscle's actual insertion can be noted by those surgeons accustomed to the

traditional medial rectus recession numbers used as guidelines for recession. For

example, if a 5.5 mm recession of the medial rectus is done in a patient whose medial

rectus inserts 4.5 mm from the limbus (not noticed by the surgeon) and a 5.5 mm

recession is done, the new insertion site is located 9.0 mm from the limbus in a normal

sized eye. This could result in an undercorrection, and in all likelihood, this occurred not

infrequently when 5.5 mm was considered the maximum medial rectus recession. On the

other hand, if in this same patient the medial rectus were recessed 10.0 mm from the

limbus, the resultant recession measured from the insertion would actually be 6.5 mm, a

number perhaps considered too large for the deviation but one which would be required

because of the medial rectus insertion site being closer to the limbus.

Use of the limbus as the point of reference for medial rectus recession allows thesurgeon to perform larger recessions safely by not exceeding the landmark of theequator. The equatorial landmark has been shown to be reliable because in patients withrefractive errors between + or - 4.00 diopters, the axial length of the eye is predictablefor the age of the patient. This has been confirmed by simple to perform axial length

measurement with the A-scan device. At the same time, the corneal dimension is alsoreliable. If it appears to be other than the normal dimension, this is obvious andmeasurement for confirmation is simple. Whether or not discovery of the pulleys will

alter this thinking is not clear now. It is known, however, that successful realignment ofcongenital esotropia occurs more frequently when measurement is carried out from thelimbus compared to the prior upper limit of recession of 5.5 mm. With larger medialrectus recession measured from the insertion now being done, first surgery alignment in
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congenital esotropia is improved, but the incidence of overcorrection is not known.

The inferior rectus inserts 6.5 mm from the limbus; the lateral rectus inserts 6.9 mm

from the limbus (range: 4.5 to 8.0 mm);* and the superior rectus inserts 7.7 mm from

the limbus. Beginning with the medial rectus and moving inferiorly and temporally, each

rectus muscle inserts farther from the limbus. The line connecting these insertions iscalled the spiral of Tillaux (Figure 27). The circumference of the ring formed by closing

the spiral is approximately 80 mm. The width of the insertion of each of the rectus

muscles is approximately 10 mm. The distance between the adjacent insertion borders is

approximately 10 mm (Figure 28).

Figure 27

The spiral of Tillaux and the relationship of

the rectus muscle insertions.

Figure 28

Width of the rectus muscle insertions

The issue can be summed up as follows: the insertion of the medial rectus muscle in esotropia tends to be

closer to the limbus than the 5.5 mm stated for the normal. Therefore, recession measured from the limbus, a

more reliable landmark, allows larger recessions to be done safely thus reducing the likelihood o

undercorrection.

The insertion of the rectus muscles can be seen relatively easily through the intact

conjunctiva. This means that the muscles location can be confirmed when the eye isrotated and the conjunctiva is brought tightly over the insertion of any of the rectus

muscles. Close observation reveals the line of insertion of the muscle, with the muscleappearing as a slightly darker and faintly raised structure beneath conjunctiva (Figure29). By confirming the rectus muscles insertion in this manner, the surgeon can locate

each of the rectus muscles accurately in roughly the 3, 6, 9, and 12 o'clock positions ofthe globe. This maneuver leads to proper traction suture or traction forceps placementand allows strategic placement of the incision through conjunctiva leading to accuratelocalization of the muscle to be operated upon. This maneuver to establish the locationof the rectus muscles should be done routinely at the outset of each eye muscle surgicalprocedure.

The rectus muscles are all approximately 40 mm long and each receives innervationfrom the undersurface (intraconal space) at the junction of the middle and posterior


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thirds of the muscle or 26 mm from the insertion. The six pairs of extraocular muscles

are characterized in Table 1.

* Although the lateral rectus insertion site is variable, it is not common to measure from the limbus for

recession of this muscle.

A B

C D

E

Figure 29

AThe superior rectus muscle seen through the intact conjunctiva and anterior Tenons capsule.

BThe insertion of the inferior rectus muscle seen through the intact conjunctiva. Note fat pad.

CThe insertion of the lateral rectus muscle seen through the intact conjunctiva.

DThe insertion of the medial rectus muscle seen through the intact conjunctiva.

EThe insertion of the lateral and inferior rectus muscles seen through the intact conjunctiva with the

inferior temporal orbital fat pad seen just inside the lower lid margin. The site of the incision for inferior

oblique exposure is shown. This view is shown from above.


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Muscle Length(mm) Nerve Point of Innervation Tendon*

(mm)

Muscle action

Medialrectus

(MR)

40 III Inferiordivision

26 mm from insertion L: 3.7W: 10.3

Adduction

Inferior

rectus

(IR)

40 III Inferior

division

26 mm from insertion L: 5.5

W: 9.8

Depression

Excycloduction

Adduction

Lateral

rectus

(LR)

40 VI 26 mm from insertion L: 8.8

W: 9.2

Abduction

Superior

rectus(SR)

40 III

Superiordivision

26 mm from insertion L: 5.8

W: 10.8

Elevation

IncycloductionAdduction

Inferior

oblique

(IO)

36 III Inferior

division

12 mm posterior to

insertion of inferior

rectus at its lateral

border

L: < 1

W: 9.4

Elevation

Excycloduction

Abduction

Superior

oblique

(SO)

60 IV 26 mm from trochlea L: 30

W: 10.7

Depression

Incycloduction

Abduction

* L - length; W - width at insertion

Table 1 Extraocular Muscles


11/15

http://www.expertconsultbook.com/expertconsult/ob/book.do?method=display&type=bookPage&

decorator=none&eid=4-u1.0-B978-1-4377-2272-7..00005-6--s0020&isbn=978-1-4377-2272-7

Tenon's capsule

Tenon's capsule is a dense, elastic, fibrovascular connective tissue layer that surrounds the globe,

except over the cornea. It also invests the anterior portions of the extraocular muscle insertions. This

structure begins near the perilimbal sclera anteriorly and extends around the globe to the optic nerve

where it blends with fibers of the dural sheath and sclera. Anterior to the insertion of the rectus

muscles, about 2 mm behind the corneal limbus, Tenon's capsule originates and is firmly adherent to

episclera. Over the surface of the globe, Tenon's capsule is separated from episclera by a loose

potential space that provides a smooth surface for ocular motility. It was the discovery of this capsule

by Tenon,[44]

and its popularization by O'Farrall and Bonnet (cited in Snyder)[43]

that led to

development of modern enucleation techniques, and abandonment of more barbaric and anatomically

mutilating surgery.
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12/15

ANATOMI BOLA MATA. BY: FAUZAN MUTTAQIEN

RONGGA ORBITA

1. Bentuk seperti piramida

2. Dibatasi dinding tulang

3. Dibagian belakang terdapat 3 lubang : foramen optic, fisura orbita sup et inf.

4. Isi :

a. Bola mata

b. 6 otot penggerak

c. Kelenjar air mata

d. Arteri

e. Saraf kranial iii, iv, dan vi

f. Lemak dan fascia

BOLA MATA

Terdiri dari :

1. Dinding bola mata :

a. Sklera

b. Kornea

2. Isi bola mata

Sklera

a. Jaringan ikat kolagen yang kenyal warna putih

b. Tebal 1 mm

c. Bagian belakang terdapat lamina kribrosa tempat menembusnya saraf optik

d. Dilapisi kapsul tenon dan dibagian depan oleh konjungtiva

e. Diantara stroma, sklera dan kapsul tenon terdapat episklera yang kaya pembuluh darah (untuk

nutrisi sklera)

f. Bagian dalam terdapat lamina fuska yang membatasi sklera dan koroid

Kornea

a. Merupakan jaringan jernih dan bening. jernih karena avaskular

b. Bentuk sebagai lingkaran, diameter diukur secara vertical 1112 mm

bila >12 mm pada anakglaukoma congenital

c. Tebal = 0,61 mm

d. Sumber nutrisi kornea :

- Pembuluh darah limbus

- Humour aqueos

- Air mata

e. Terdiri dari 5 lapisan :


13/15

1. Epitel; 5 6 lapisan sel, bentuk sel gepeng, ujung saraf kornea pada epitel (cab. N. V),

regenerasi cukup baik, jika terjadi kerusakan tidak timbul jaringan parut

2. Membran bowman; tipis yang homogen, terdiri dari serat kolagen yang kuat, jika terjadi

kerusakan timbul jaringan parut

3. Stroma; lapisan yang paling tebal (90%), tersusun atas serabut lamelar terjalin satu sama

lainnya, jika terjadi kerusakan timbul jaringan parut dan leukoma4. Membran discement; lapisan tipis kenyal, kuat, bening, tidak berstruktur, sebagai barrier

terhadap mikroorganisme dan pembuluh darah

5. Endotel; satu lapis sel, mempertahankan kejernihan kornea, tidak ada kemampuan

regenerasi

paling tebalstroma,

paling kuatdescement

paling pekaendotel

Kelainan kornea yang menyebabkan gangguan refraksi:

1. radang

2. TIO meningkat

3. sikatriks dari ulkus yang sembuh

Isi Bola Mata

1. Lensa

a. Bening, bikonveks, tebal 5 mm, diameter 9 mm

b. Difiksasi oleh zonula zinn

c. Terdiri dari kapsul, korteks, dan nukleus

d. Bertambah usia, nukleus membesar

e. Fungsi : membias cahaya menjadi fokus

f. Merupakan salah satu media refrakta

g. Komposisi : 0,5% air, 35% protein (kristalin , , )

h. Tidak mempunyai pembuluh darah dan persarafan

i. Semakin bertambah usia nukleus semakin membesar

j. Fungsi untuk membiaskan cahayak. Kekuatan +20 Dioptri

2. Uvea

a. Lapisan kedua dinding bola mata

b. Jaringan lunak

c. Terdiri dari 3 bagian : iris, badan siliar, koroid

Iris:

a. Membran berwarna

b. Bentuk sirkular, ditengah terdapat pupil dengan diameter 35 mm

c. Berpangkal pada badan siliar


14/15

d. Permukaan iris banyak lekukan (kriptae)

e. Otot iris = otot polos : sfingter pupil, dilator pupil

f. Pembuluh darah :

- Sirkulus major = pangkal iris

- Sirkulus minor = pupil

g. Saraf : n. Nasosiliar cabang n. Iii- Simpatis = midriasi

- Parasimpatis = miosis

Badan Siliar :

a. Mulai dari pangkal iris oraserata

b. Terdiri dari :

- Prosesus siliaris, fungsi : produksi h a

- Otot silliar (sirkular, radial, meridional), fungsi : akomodasi (lensa cembung)

Koroid :

a. Warna cokelat tua, diantara retina dan sklera

b. Mulai dari oraserata terdapat papil optik

c. Kaya pembuluh darah

d. Fungsi : nutrisi retina bagian luar

3. Badan kaca (corpus vitreus)

a. Sebagian mengisi bola mata

b. Tidak berwrna, bening, konsistensi lunak

c. Dilapisi membran hialoid

d. Avaskuler

e. Mendapat nutrisi dari koroid, badan siliar, dan retina

Kelainan, kekeruhan karena:

- pusendoftalmitis

- darahhemoftalmitis

- degenerasiretinopati diabetik

gunakan oftalmoskop untuk melihat kelainan pada korpus vitreus

4. Retinaa. Membran bening dan tipis 1 mm

b. Terdiri dari serabut saraf optik

c. Letak antara badan kaca dan koroid berakhir pada oraserata

d. Terdapat makula lutea (bintik kuning), diameter 12 mm sebagai pusat penglihatan

e. 3 mm ke arah nasal terdapat papil saraf optik (bintik buta)

f. Arteri dan vna retina sentral masuk ke bola mata ditengah papil saraf optik

g. Ada 10 lapisan :

- Membran limitan dalam

- Lapisan serabut saraf, terdapat cabang utama pembuluh darah retina

- Lapisan sel ganglion, sel saraf bercabang disini

- Lapisan pleksiform dalam- Lapisan nukleus dalam, terbentuk dari badan dan nukleus sel bipolar


15/15

- Lapisan pleksiform luar

- Membran limitan luar

- Lapisan nukleus luar, terdiri dari nukleus sel kerucut dan batang

- Lapisan sel batang dan kerucut, fungsinya menangkap sinar

- Lapisan epitel pigmen

Humor Aquos

normalnya jernih

kelainan humor aquos yang mengganggu refraksi:

- radang

- hipopion (pus)

- hifema (perdarahan)

Bilik mata depan (COA)batas kornea sampai iris dan kapsul anterior lensa

Bilik mata belakang (COP)batas dari lapian belakang iris sampai lensa (zonula zinn)

Documents

Ref Firman