anatomy of eye detaile discription regarding the conjunctiva, eyelid, cornea, sclera

1. ANATOMY OF EYE
Dr Sparsha S K
1st yr shalakya tantra
AAMC
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2. EYEBALL
• Each eyeball is a cystic structure kept
distended by the pressure inside it.
• Shape
the eyeball is not a sphere but an
oblate spheroid.
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3. • Poles. The central point on the
maximal convexities of the
anterior and posterior curvatures
of the eyeball is called the anterior
and posterior pole, respectively.
• Equator of the eyeball lies at the
mid plane between the two poles .
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4. DIMENSIONS OF AN ADULT
EYEBALL
Anteroposterior diameter 24 mm
Horizontal diameter 23.5 mm
Vertical diameter 23 mm
Circumference 75 mm
Volume 6.5 ml
Weight 7 gm
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5. COATS OF THE
EYEBALL
outer(fibrous coat), middle (vascular coat) and
inner(nervous coat).
Fibrous coat: dense strong wall which protects the
intraocular contents. Anterior 1/6th of this fibrous
Coat is transparent is called Cornea. Posterior 5/6th
opaque part is Called Sclera. Cornea is set into the
sclera like a watch glass. Junction of the cornea and
sclera is called Limbus. Conjunctiva is firmly
attached at the limbus.
Vascular coat (uveal tissue). It supplies nutrition.
It consists of three parts, from anterior to posterior,
Which are: Iris, Ciliary body and Choroid.
Nervous coat (retina). It is concerned with visual
functions and projects to visual cortex through the
visual pathway.
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6. SEGMENTS AND CHAMBERS OF THE EYEBALL
. ANTERIOR
SEGMENTS
POSTERIOR
SEGMENTS
Crystalline lens Vitreous humour
Iris Retina
Cornea Choroid
Aqueous humour-
Anterior and posterior
chambers
Optic disc.
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7. ANTERIOR CHAMBER.
 anteriorly by the back of cornea, and posteriorly by the
anterior surface of iris and part of ciliary body.
 2.5 mm deep in the centre.
 slightly shallower in hypermetropes and deeper in
myopes, but is almost equal in the two eyes of the
same individual.
 It contains about 0.25 ml of the aqueous humour.
 It communicates with posterior chamber through the
pupil.
POSTERIOR CHAMBER.
 triangular space containing 0.06 ml of aqueous
humour.
 It is bounded anteriorly by the posterior surface of iris
and part of ciliary body, posteriorly by the crystalline
lens and its zonules, and laterally by the ciliary body.
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8. ORBIT AND APPENDAGES OF THE
EYE
• Each eyeball is suspended by extraocular muscles and fascial sheaths in a
quadrilateral pyramidshaped bony cavity called orbit .
• Each eyeball is located in the anterior orbit, nearer to the roof and lateral
wall than to the floor and medial wall.
• Each eye is protected anteriorly by two shutters called the eyelids.
• The anterior part of the sclera and posterior surface of lids are lined by a
thin membrane called conjunctiva.
• For smooth functioning, the cornea and conjunctiva are to be kept moist by
tears which are produced by lacrimal gland and drained by the lacrimal
passages.
• These structures (eyelids, eyebrows, conjunctiva and lacrimal apparatus)
are collectively called ‘the appendages of the eye’.
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9. BLOOD VESSELS AND NERVES
• ARTERIES
Ophthalmic artery, a branch of internal carotid artery,
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i. Ocular group II. Orbital group
• Central retinal artery Lacrimal artery - Lateral palpebral artery
•Long posterior ciliary aiteries • Recurrent meningeal artery
• Short posterior ciliary arteries • Supraorbita1 artery
• Muscular branches
-Anterior ciliary arteries
• Medial palpebral artery
• Posterior ethmoidal artery
• Anterior ethmoida1 arte1y
• Dorsal nasal artery (terminal branch)
• Supratroch1ear artery (terminal branch

10. VEINS
• Central retinal vein which drains blood from the retina;
• Anterior ciliary veins, short posterior ciliary veins and venae verticosae
which drain blood from the uveal tissue.
• Main venous channels which ultimately get tributaries from various orbital
structures include
a. Superior ophthalmic vein
b. Inferior ophthalmic vein
c. Middle ophthalmic vein
d. Medial ophthalmic vein
e. Angular vein,
f. Cavernous sinus
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11. NERVES
SENSORY NERVES : Ophthalmic nerve
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l. Lacrimal nerve.
2. Frontal nerve. •Supratrochlear nerve
•Supraorbital nerves
3. Nasociliary nerve. •long ciliary nerves
•Communicating branches to ciliary ganglion
•Posterior ethmoidal nerve
•Anterior ethmoidal nerve
•lnfratrochlear nerve

12. MOTOR NERVES
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Motor nerves Relation with muscle
Oculomotor(3rd)
 Superior division
 Inferior division
Superior rectus
Medial rectus , Inferior rectus,
Inferior oblique
Trochlear (4th) Superior oblique
Abducens (6th) Lateral rectus
Facial (7th) Orbicularis oculi

13. LYMPHATIC DRAINAGE
Lymphatics draining the eyelids, conjunctiva and orbital tissues are
arranged in two groups
Medial group of lymphatics sub - mandibular lymph nodes
Lateral group of lymphatics subauricular lymph nodes
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14. APPENDAGES OF THE EYE
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15. CONJUNCTIVA
• Conjunctiva is a translucent
mucous membrane which
lines the posterior surface of
the eyelids and anterior aspect
of the eyeball.
• It stretches from the lid
margin to the limbus, and
encloses a complex space
called conjunctival sac which
is open in front at the
palpebral fissure
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16. PARTS OF CONJUNCTIVA
1. PALPEBRAL CONJUNCTIVA. It lines the lids and can be
subdivided into marginal, tarsal and orbital conjunctiva.
Marginal
conjunctiva
extends from the lid margin to about 2 mm on the back of lid up to a
shallow groove, the sulcus subtarsalis. It is actually a transitional zone
between skin and the conjunctiva proper
Tarsal
conjunctiva
is thin, transparent and highly vascular. It is firmly adherent to the whole
tarsal plate in the upper lid. In the lower lid, it is adherent only to half
width of the tarsus. The tarsal glands are seen through it as yellow streaks
Orbital
part
lies loose between the tarsal plate and fornix
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17. 2. Bulbar conjunctiva
 It is thin, transparent and lies loose over the underlying structures and
thus can be moved easily. It is separated from the anterior sclera by
episcleral tissue and Tenon’s capsule.
 A 3 mm ridge of bulbar conjunctiva around the cornea is called limbal
conjunctiva. In the area of limbus, the conjunctiva, Tenon’s capsule and
the episcleral tissue are fused into a dense tissue which is strongly
adherent to the underlying corneoscleral junction.
 At the limbus, the epithelium of conjunctiva becomes continuous with
that of cornea.
3. Conjunctival fornix.
 It is a continuous circular culde-sac which is broken only on the medial
side by caruncle and the plica semilunaris. Conjunctival fornix joins the
bulbar conjunctiva with the palpebral conjunctiva. It can be subdivided
into superior, inferior, medial and lateral fornices.
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18. STRUCTURE OF
CONJUNCTIVA
1
• Epithelium
2
• Adenoid layer.
3
• Fibrous layer
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19. GLANDS OF CONJUNCTIVA
1. MUCIN SECRETORY GLANDS.
 Goblet cells (within the epithelium),
 Crypts of Henle (tarsal conjunctiva), and
 Glands of Manz (found in limbal conjunctiva).
These glands secrete mucus which is essential for wetting
the cornea and conjunctiva.
2. ACCESSORY LACRIMAL GLANDS.
 Glands of Krause, present in subconjunctival connective
tissue of fornices, about 42 in the upper fornix and 8 in
the lower fornix
 Glands of Wolfring, present along the upper border of
superior tarsus and along the lower border of inferior
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20. PLICA SEMILUNARIS
It is a pinkish crescentric fold of conjunctiva,
present in the medial canthus. Its lateral free
border is concave. It is a vestigeal structure in
human beings.
CARUNCLE
The caruncle is a small, ovoid, pinkish mass,
situated in the inner canthus, just medial to the
plica semilunaris. it is a piece of modified skin
and so is covered with stratified squamous
epithelium and contains sweat glands, sebaceous
glands and hair follicles.
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21. BLOOD SUPPLY
ARTERIES 1) peripheral arterial arcade of the
eyelid
2) marginal arcade of the eyelid
3) anterior ciliary arteries
Palpebral
conjunctiva
and fornices
peripheral and marginal arterial arcades
of the eyelids.
Bulbar
conjunctiva
1. Anterior conjunctival arteries
2. posterior conjunctival arteries
VEINS
conjunctiva drain into the
venous plexus of eyelids
LYMPHATIC DRAINAGE
lateral side drain into
preauricular lymph nodes
medial side into the
submandibular lymph nodes
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22. 10/16/2023 22

23. NERVE SUPPLY OF CONJUNCTIVA
• A circumcorneal zone of conjunctiva is supplied by the branches from long
ciliary nerves which supply the cornea.
• Rest of the conjunctiva is supplied by the branches from lacrimal,
infratrochlear, supratrochlear, supraorbital and frontal nerves
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24. EYELIDS
• Eyelids are mobile tissue curtains placed
infront of the eyeballs.
• It acts as shutters protecting the eyes from
injuries and excessive light
• perform an important function of spreading the
tear film over the cornea and conjuctiva
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25. EXTENT
• Upper eyelid
From eyebrows downwards to end in a free
margin
which forms the superior boundary of palpabral
fissure
• Lower eyelid
merge into skin of the cheek
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26. LID FOLDS
• SUPERIOR LID FOLD
Upper eyelid is divided by the superior lid fold into an
orbital portion-above
tarsal portion –below
• INFERIOR LID FOLD
Present on the skin of the lower eyelids
Formed by the fibrous slips that arise from the fascia
of inferior rectus
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27. POSITION OF EYELIDS
In primary position of gaze eyelid covers:
• Upper eyelid covers 1/6th of cornea
• Lower eyelid just touches the cornea
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28. CANTHI
Eyelids meet at medial and lateral canthi
Lateral canthus
Lie in contact with the eyeball
Medial canthus
Rounded
seperated from the globe by tear lake(lacus lacrimalis)
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29. EYELID MARGINS
• The opposing margins of the eyelids are nearly flat
• It is divided into 2 parts by the lacrimal papilla
I. Medial portion
• Extends from punctum medially to the medial canthal angle termed as
lacrimal portion
II. Lateral ciliary portion
• Consist of a rounded anterior border, a sharp posterior border and an
inter-marginal strip between the 2 borders
Grey line- junction of skin and conjuctiva
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30. EYELASHES
• Arranged in 2-3 rows
• Those in upper eyelid- directed forward, upward and
backward
• In lower eyelid- directed forward, downward and
backwards
• When lid close eyelases donot interlace
• Each cilium has a lifespan of some 3-4 months
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31. PALPEBRALAPERTURE
• It is the elliptical space between the upper and lower eyelid margins
• At birth
Horizontally- 18-21mm
Vertically - 8 mm
• In adults
Horizontally- 28-30mm
Vertically - 9-11mm
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32. STRUCTURE
From without inwards each eyelid consist of following layers.
i. Skin
ii. Layers of subcutaneous areolar tissue
iii. Layer of striated muscles
iv. Submuscular areolar tissue
v. Fibrous layer
vi. Layer of non-striated muscle fibres
vii. Conjuctiva
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33. 1.SKIN
• Skin covering the eyelid is elastic, having a fine texture and is thinnest in the body
• Nasal part of the skin is smooth, shining and greasy in comparison to the temporal
part
Microscopic structure
Epidermis
• Composed of 6-7 layers of stratified squamous epithelium
• Basal layer of the epidermis shows the presence of unicellular sebaceous glands
and numerous sweat gland
Dermis
• Composed of thin layer of dense conective tissue with rich network of elastic
fibres, blood vessels, lymphatics and nerves
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34. 2.SUBCUTANEOUS AREOLAR TISSUE
• Beneath the skin
• Containing no fat
• Readily distended by oedema or blood
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35. 3.LAYER OF STRIATED MUSCLE
• Consist of orbicularis muscle which forms a thin oval sheet across the eyelids
• Upper eyelid also contains levator muscle
Orbicularis oculi muscle
Divided into 2 parts
Orbital part
Palpebral part
Orbital part
• Forms the most peripheral fibres of the orbicularis which arise from the anterior
part of the medial palpebral ligament and the adjacent bones
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36. Palpebral part
• Subdivided into – preseptal
pretarsal portions
• Preseptal fibres arise from the lacrimal fascia, posterior lacrimal crest and
the anterior part of the medial palpebral ligament
• Pretarsal fibres also arise from by a deep head and a superficial head
Functions of Orbicularis oculi
Orbital part
• Forced closure of eyelids
• Thus pull eyebrows downwards
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37. Palpebral part
• Helps in gentle closure during blinking, sleep, soft voluntary closure
Levator Palpebrae Superioris
• Arises from the apex of the orbit and is inserted by 3 parts on the skin of
lid, anterior surface of the tarsal plate and conjuctiva of superior fornix
• It raises the upper lid
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38. 4.SUBMUSCULAR AREOLAR TISSUE
• It is a layer of loose connective tissue present b/w the orbicularis muscle
and fibrous layer
• Nerves and vessels lie in this layer
• Slpits lid into anterior and posterior lamina
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39. 5.FIBROUS LAYER
• It is the framework of the lids
• Consist of central thick part - the tarsal plate
peripheral thin part -the septum orbitale
i. Tarsal plate
• There are two plates of dense connective tissue, one for each lid, which
give shape and firmness to the lids.
• The upper and lower tarsal plates join with each other at medial and lateral
canthi; and are attached to the orbital margins through medial and lateral
palpebral ligaments.
• In the substance of the tarsal plates lie meibomian
glands in parallel rows.
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40. Septum orbitale (palpebral fascia).
It is a thin membrane of connective tissue attached
• centrally to the tarsal plates
• peripherally to periosteum of the orbital margin
It is perforated by nerves, vessels and levator palpebrae superioris (LPS) muscle,
which enter the lids from the orbit.
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41. 6.LAYER OF NON-STRIATED MUSCLE
FIBRES
• It consists of the palpebral muscle of Muller which lies deep to the septum
orbitale in both the lids.
In the upper lid
It arises from the fibres of LPS muscle
In the lower lid
from prolongation of the inferior rectus muscle;and is inserted on the
peripheral margins of the tarsal plate.
• It is supplied by sympathetic fibres
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42. GLANDS OF EYELID
1. Meibomian gland
2. Glands of Zeis
3. Glands of Moll
4. Accessory lacrimal glands of Wolfring
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43. MEIBOMIAN GLAND
• These are also known as tarsal glands
• Present in the stroma of tarsal plate arranged vertically
Number
In the upper lid – 30-40
In the lower lid - 20-40
• They are modified sebaceous glands.
• Their ducts open at the lid margin.
• Their secretion constitutes the oily layer of tear film.
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44. FUNCTIONS
• The oily marginal strip prevents the overflow of tears across the lid margin
• From the oily layer of tear film over cornea and bulbar conjunctiva which
prevents evaporation of tears and allows smooth movements of the eyelids
over globe
• Ensure the air-tight closure of
the eyelids
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45. GLANDS OF ZIES
• These are also sebaceous glands which open into the follicles of eyelashes.
FUNCTION
• Secretion prevents the eyelashes from becoming dry and brittle
• Also contributes towards the oily layer of the tear film
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46. GLANDS OF MOLL
• These are modified sweat glands situated near the hair follicle.
• They open into the hair follicles or into the ducts of Zeis glands.
• They donot open directly onto the skin surface as elsewhere
ACCESSORY LACRIMAL GLANDS OF
WOLFRING
• These are present near the upper border of the tarsal plate
• These are about 2 to 5 in the upper lid and 2 to 3 in the lower lid
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47. FIBROUS
COAT.
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48. CORNEA
• Cornea is a transparent, avascular, watch-glass
like structure.
• It forms anterior one-sixth of the outer fibrous
coat of the eyeball.
DIMENSIONS
• Anterior surface -elliptical with an average
horizontal diameter of 11.7 mm and vertical
diameter of 11 mm.
• Posterior surface - circular with an average
diameter of 11.5 mm.
THICKNESS
• Centre - 0.5 to 0.6 mm
• Periphery - 1 to 1.2 mm.
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49. RADIUS OF CURVATURE.
• Anterior - 7.8 mm
• Posterior - 6.5 mm
REFRACTIVE INDEX 1.376.
REFRACTIVE POWER 45 dioptres,
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50. HISTOLOGY
Cornea consists of six layers.
From anterior to posterior
these are:
1. Epithelium,
2. Bowman’s membrane,
3. Substantia propria(corneal
stroma),
4. Pre descemet’s membrane(dua’s
layer),
5. Descemet’s membrane
6. Endothelium
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51. 1. EPITHELIUM
 It is of stratified squamous type and becomes continuous with epithelium of
bulbar conjunctiva at the limbus.
 It consists of 5–6 layers of cells. The deepest (basal) layer is made up of
columnar cells, next 2–3 layers of wing or umbrella cells and the most
superficial two layers are made of flattened cells.
 Tight junctions between superficial epithelial cells prevent penetration of tear
fluid into the stroma.
2. BOWMAN’S MEMBRANE.
 This layer consists of acellular mass of condensed collagen fibrils.
 It is about 12 mm in thickness and binds the corneal stroma anteriorly with
basement membrane of the epithelium.
3 STROMA (SUBSTANTIA PROPRIA)
 This layer is about 0.5 mm in thickness and constitutes most of the cornea
(90% of total thickness).
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52. 4. PRE–DESCEMET’S MEMBRANE, (Dua’s layer)
 Located anterior to the Descemet’s membrane
 it is about 15 micrometer thick acellular structure which is very strong and
imprevious to air.
5. DESCEMET’S MEMBRANE (POSTERIOR ELASTIC LAMINA).
 strong homogenous basement membrane of the corneal endothelium which is
separated from the stroma by pre-Descemet’s membrane.
 maintain the integrity of eyeball
 Descemet’s membrane consists of collagen and glycoproteins.
6. ENDOTHELIUM
 consists of a single layer of flat polygonal (mainly hexagonal) epithelial cells
(misnamed as endothelium) which on slit-lamp biomicroscopy appear as a mosaic
 The cell density of endothelium is around 3000 cells/mm2
 cells keeps cornea dehydrate
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53. • BLOOD SUPPLY
Cornea is an avascular structure.
NERVE SUPPLY
Cornea is supplied by anterior ciliary nerves which are branches of ophthalmic
division of the 5th cranial nerve.
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54. CLINICAL ANATOMY
 Cornea can be grafted from one person to the other, as it is avascular.
 Injury to cornea may cause opacities. These opacities may interfere with
vision.
 Eye is a very sensitive organ and even a dust particle gives rise to pain.
 The anteroposterior diameter of the eyeball and shape and curvature of the
cornea determine the focal point. Changes in these result in myopia or
short-sightedness, hypermetropia or longsightedness
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55. SCLERA
• Posterior five-sixth opaque part
• Its whole outer surface is covered by
tenon’s capsule.
• Anterior part is covered by bulbar
conjunctiva.
• Its inner surface lies in contact with choroid
with a potential suprachoroidal space in
between.
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56. THICKNESS
• thinner in children than the adults and in females than the males.
• Sclera is thickest posteriorly (1 mm) and gradually becomes thin when traced
anteriorly.
• It is thinnest at the insertion of extraocular muscles (0.3 mm).
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57. APERTURES.
Sclera is pierced by three sets of apertures
apertures site
Posterior around the optic
nerve
transmit long
and short ciliary
nerves and
vessels
Middle slightly posterior
to the equator
four vortex veins
Anterior 3 to 4 mm away
from the limbus.
Anterior ciliary
vessels and
branches from
long ciliary
nerves
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58. MICROSCOPIC STRUCTURE.
1. EPISCLERAL TISSUE.
It is a thin, dense vascularised layer of connective
Tissue which covers the sclera proper. Fine
Fibroblasts, macrophages and
Lymphocytes are present in this layer.
2. SCLERA PROPER.
It is an avascular structure which consists of
Dense bundles of collagen fibres.
3. LAMINA FUSCA.
It is the innermost part of sclera. It is brownish in
Colour owing to the presence of pigmented cells.
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59. NERVE SUPPLY.
Sclera is supplied by branches from the long ciliary nerves which pierce it 2–4mm
from the limbus to form a plexus
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60. UVEAL TRACT
• Uveal tissue constitutes the middle vascular coat of the eyeball.
• From anterior to posterior, it can be divided into three parts
A. Iris
B. Ciliary body
C. Choroid.
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61. IRIS
• Iris is the anterior most part of the uveal tract.
• It is a thin circular disc corresponding to the diaphragm of a camera.
• In its centre is an aperture of about 4 mm diameter called pupil which
regulates the amount of light reaching the retina.
• At periphery, the iris is attached to the middle of anterior surface of the
ciliary body. It divides the space between the cornea and lens into anterior
and posterior chambers.
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62. MACROSCOPIC APPEARANCE
Anterior surface of the iris can be divided into
a ciliary zone and a pupillary zone by a zigzag
line called collarette
1. Ciliary zone. It presents series of radial
streaks due to underlying radial blood
vessels and crypts which are depressions
where superficial layer of iris is missing.
Crypts are arranged in two rows—the
peripheral present near the iris root and the
central present near the collarette.
2. Pupillary zone. This part of the iris lies
between the collarette and pigmented
pupillary frill and is relatively smooth and
flat
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63. MICROSCOPIC STRUCTURE
1. Anterior limiting layer. It is the anterior most condensed part
of the stroma. It consists of melanocytes and fibroblasts.. The
definitive colour of the iris depends on this layer. In blue iris
this layer is thin and contains few pigment cells. While in
brown iris it is thick and densely pigmented.
2. Iris stroma. It consists of loosely arranged collagenous
network in which are embedded the sphincter pupillae muscle,
dilator pupillae muscle, vessels, nerves, pigment cells and
other cells which include lymphocytes, fibroblasts,
macrophages and mast cells.
3. Anterior epithelial layer. It is anterior continuation of the
pigment epithelium of retina and ciliary body. This layer gives
rise to the dilator pupillae muscle.
4. Posterior pigmented epithelial layer. It is anterior continuation
of the nonpigmented epithelium of ciliary body. At the
pupillary margin, it forms the pigmented frill and becomes
continuous with the anterior pigmented epithelial layer
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64. 10/16/2023 64

65. CILIARY BODY
• Ciliary body is forward continuation of the choroid
at ora serrata.
• In cut-section, it is triangular in shape.
• The anterior side of the triangle forms the part of
the angle of anterior and posterior chambers.
• In its middle the iris is attached.
• The outer side of the triangle lies against the sclera
with a suprachoroidal space in between.
• The inner side of the triangle is divided into two
parts.
 The anterior part (about 2 mm) having finger-like
ciliary processes is called pars plicata
 the posterior smooth part (about 4 mm) is called
pars plana
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66. MICROSCOPIC STRUCTURE
• From without inwards ciliary body consists of following five layers
1. Supraciliary lamina. It is the outermost condensed part of the stroma and
consists of pigmented collagen fibres. Posteriorly, it is the continuation of
suprachoroidal lamina and anteriorly it becomes continuous with the
anterior limiting membrane of iris.
2. Stroma of the ciliary body. It consists of connective tissue of collagen and
fibroblasts. Embedded in the stroma are ciliary muscle, vessels, nerves,
pigment and other cells.
3. Layer of pigmented epithelium . It is forward continuation of the retinal
pigment epithelium. Anteriorly, it is continuous with the anterior
pigmented epithelium of the iris
4. Layer of nonpigmented epithelium low columnar or cuboidal cells, and is
the forward continuation of the sensory retina. It continues anteriorly as
the posterior (internal) pigmented epithelium of the iris.
5. Internal limiting membrane. It is the forward continuation of the internal
limiting membrane of the retina. It lines the nonpigmented epithelial
layer.
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67. CILIARY PROCESSES
• These are finger-like projections from the pars plicata
part of the ciliary body.
• These are about 70–80 in number.
• Each process is about 2 mm long and 0.5 mm in
diameter.
• These are white in colour.
STRUCTURE
Each process is lined by two layers of epithelial cells. The
core of the ciliary process contains blood vessels and loose
connective tissue. These processes are the site of aqueous
production
FUNCTIONS OF CILIARY BODY
• Formation of aqueous humour.
• Ciliary muscles help in accommodation
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68. CHOROID
• Choroid is posterior most part of the
vascular coat of the eyeball.
• It extends from optic disc to the ora
serrata.
• Its inner surface is smooth, brown
and lies in contact with pigment
epithelium of the retina.
• The outer surface is rough and lies in
contact with the sclera.
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69. MICROSCOPIC STRUCTURE
1. Suprachoroidal lamina.
It is a thin membrane of condensed collagen fibres, melanocytes and fibroblasts. It is
continuous anteriorly with the supraciliary lamina. The potential space between the
membrane and sclera is called suprachoroidal space which contains long and short
posterior ciliary arteries and nerves.
2. Stroma of the choroid.
It consists of loose collagenous tissue with some elastic and reticulum fibres. It also
contains pigment cells and plasma cells. Its main bulk is formed by vessels which are
arranged in three layers. From without inwards these are: (i) layer of large vessels
(Hailer’s layer), (ii) layer of medium vessels (Sattler’s layer) and (iii) layer of
choriocapillaris which nourishes the outer layers of the retina.
3. Basal lamina.
It is also called Bruch’s membrane and lines the layer of choriocapillaris. It lies in
approximation with pigment epithelium of the retina
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70. BLOOD SUPPLY OF UVEAL TRACT
ARTERIAL SUPPLY
• 1. Short posterior ciliary arteries.
• 2. Long posterior ciliary arteries.
• 3. Anterior ciliary arteries.
VENOUS DRAINAGE
A series of small veins which drain blood from the iris, ciliary
body and
choroid join to form the vortex veins.
The vortex veins are four in number—
1. superior temporal,
2. inferior temporal,
3. superior nasal
4. inferior nasal.
They pierce the sclera behind the equator and drain into
superior and interior ophthalmic veins, which in turn,
drain into the cavernous sinus
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