The common carotid artery divides into the internal and external carotid arteries. The internal carotid artery supplies structures within the cranium including the eye. The external carotid artery supplies the superficial head and neck. The ophthalmic artery, a branch of the internal carotid, gives rise to numerous branches that supply the eye and surrounding structures. These branches anastomose to form networks that provide the eye and orbit with their blood supply. Venous drainage from the eye and orbit occurs primarily through the superior and inferior ophthalmic veins which drain into the cavernous sinus.

1. G.Sony
B. Johnson
B. kalyan Srinivas

2. Arterial blood supply :
Common carotid artery divides into :
Internal carotid artery
External carotid artery

3. Arterial blood supply:
Internal carotid artery:
It supplies the structures within the
cranium , including the eye and related
structures.
External carotid artery:
It supplies the superficial areas of the
head and neck, and also small portion of
ocular adnexa.
Note: eyelids and conjunctiva supplied by
both internal and external artery.

4. Branches of ophthalmic artery:
• Central retinal artery.
• Lacrimal artery (terminates into zygomatic branches)
• Supra – orbital artery.
• Posterior ciliary artery
- long posterior ciliary arteries ( 2 arteries)
- short posterior ciliary arteries ( 10 to 20 arteries )
• Muscular arteries
• Ethmoidal arteries
- anterior E. arteries
- posterior E. arteries
• Anterior ciliary arteries
• Palpabral arteries
-superior
-inferior
• Dorsonasal artery
• Supratrochlear artery

5. Order of origin of branches of
ophthalmic artery:

7. Central retinal artery :
• One of the first branches of the ophthalmic artery.
• The artery runs forward a short distance before entering the meningeal sheath of the nerve about 10
to 12 mm behind the globe.
• While within the O.N the artery provides branches (collateral branches) to the nerve and pia mater.
• The CRA passes through the lamina cribrosa and the optic disc just nasal to the center, branching
superiorly and inferiorly.

8. Lacrimal artery :
• One of the largest branches derived from the ophthalmic artery. Runs forward with lacrimal
nerve along the lateral rectus muscle.
Branches include:
• Recurrent meningeal artery –forms an anastomose with middle meningeal artery(a branch
from the external carotid artery)
• Zygomaticotemporal artery – passes through zygamatico temporal fossa and anastomose
deep temporal arteries.
• Zygomaticofacial artery –appears on the cheek through zygomaticofacial foramen and
anastomose with facialarteries.
• Lateral palpebral arteries – passes through gland and enters upper and lower eyelids.
• Palpabral arcades.
• Another terminal branches enters conjunctiva and forms capillary network.

9. Posterior ciliary arteries:
Divide into 2 long posterior ciliary arteries and 20 posterior ciliary
arteries.
• Short posterior ciliary arteries : Enter the sclera in a ring
around O.N form arterial network in choriodal stroma.
Take part in the formation of circle of zinn.
• Long posterior ciliary arteries: Runs between the sclera and the
choroid to the globe . The arteries enters the ciliary body and
branch superiorly and inferiorly and forms major arterial circle
of the iris

10. Anterior ciliary arteries
 Seven arteries two from each rectus mucles, except LR muscle which provides only such
artery.
 Takes part in the formation of Major circle of the iris along with long posterior ciliary
artery.
 Supplies to ciliary body and iris and also forms conjunctival plexus.

11. Ethmoid arteries:
 Posterior ethmoid artery- passes through the p.ethmiod sinus and sphenoid sinus and supply the
upper part of the nasal mucosa.
 Anterior ethmoid artery – passes through the a.ethmoid canal and supplies a.ethmoid, sphenoid
sinus, the frontal sinus,nasal cavity and the skin of the nose.
Supraorbital artery :
 Runs upward to a position superior to extraocular muscles and turns anteriorly along with
supraorbital nerve.
 Often dividing into branches to supply the skin and the muscles of the forehead and scalp.
 Anastomose with the supratroclear ,anterior temporal artery (external carotid artery).
 Sends branches to SR,SO & levator muscles,periorbita.
Mucular arteries:
 Branches;
 Lateral(superior) – LR ,SR ,SO & levator mucles
 Medial (inferior) – MR, IR, IO.

12. Medial palpebral arteries :
 Branches either directly from ophthalmic artery or from dorsonasal artery near trochlea of SO.
 Pierce the orbital septum on either side medial palpebral ligament and enter the superior and inferior
eyelids, and these branches runs through eyelid and forms arch between the O.O muscle and tarsal
plate.
 These anastomose with the lacrimal artery and the form the vessels- palpebral arcades.
 Marginal arcade
 Perpheral arcade supply to eyelid structures .
 other branches supplies to medial canthus.
Supratrochlear artery:
 one of terminal branch of Ophthalmic artery.
 supplies the skin ,muscles of forehead and scalp.
 Anastomoses with supraorbital ,opp. supratroclear and
 anterior temporal artery( external carotid artery).
Dorsonasal artery:
 Supplies lacrimal sac runs along the nose to anasmose with angular artery.

13. External carotid artery
Branches that supply the globe and orbit are;
Facial artery
- angular artery – supplies to medial canthus ,lacrimal sac, medial part of lower lid & skin of the cheek.
Some branches anastomoses with infraorbital artery & dorsonasal artery.
Superficial temporal artery;
- Anterior temporal artery
- Zygomatic temporal artery supplies areas near the orbit.
- Transverse facial artery
Maxillary artery
Supplies lower lid , lacrimal sac
anastomoses with angular artery and dorso nasal artery.

14. Venous drainage
• The orbit has two ophthalmic veins;
-Superior
-Inferior
• Central retinal vein
• Vortex veins
• Anterior ciliary veins

15. Superior ophthalmic vein :
 Formed by union of supraorbital & angular vein.
 Communicates with central retinal vein, receives inferior ophthalmic vein & 2 vorticose veins from
the upper part of the eyeball.
 Leaves the orbit through superior orbital fissure to join cavernous sinus.
Inferior ophthalmic vein :
 Arises from the venous plexus in orbital floor.
 Communicates with pterygoid venous plexus.
 Receives muscular branches & 2 inferior vorticose vein.
 Joins superior ophthalmic vein or drains directly into the cavernous sinus.
Infraorbital vein :

16. Central retinal vein :
This vessel leaves the optic nerve approx. 10 to 12 mm behind the lamina
cribrosa alongside the central retinal artery.
It emerges from the meningeal sheath of the optic nerve and either joins
the superior ophthalmic vein or exit orbit and drain into cavernous sinus.
Vortex veins :
Drains the choroid , usually one of four or five is located in each quardrant
These veins exits the globe 6mm posterior to equator.
Can be seen with an indirect ophthalmoscope and a dilated pupil.
Anterior ciliary veins :
This recieves branches from the conjunctival pupillary network
then accompany the anterior ciliary arteries , pierce the sclera,
And join with the muscular veins.

18. Cavernous sinus
 Formed by splitting of the dura matter on
the each side of the sphenoid bone.
 Extends from superior orbital fissure to
petrous portion of the temporal bone.
 Internal carotid artery and abducens
nerve are located medially with in the
sinus.
 Oculomotor ophthalmic and maxillary
nerves are found In lateral wall of the
sinus.
 Caverneous sinus drains into superior and
inferior petrosal sinus and this both drains
into internal jugular vein.

19. Lymphatic drainage
system of eye
Submandibular lymph nodes:
-Medial aspects of the lids and the medial canthus
structures
Parotid lymph nodes:
-Lateral eye lids and lacrimal glands