OVERVIEW OCULAR CIRCULATION

Question 1

Which specific arteries do the following:

• help supply the iris and ciliary body
• help supply the choroid posterior to the equator
• supply the choroid anterior to the equator
• help supply the sclera
• help supply the laminar part of the optic nerve

Answer 1

• Long Posterior Ciliary Arteries (2) + Anterior Ciliary Arteries (7) (as part of MACOTI)
• Short Posterior Ciliary Arteries (15-20)
• Long Posterior Ciliary Arteries (2) at the Ora Serrata (and recurrent branches of anterior ciliary) (7)
• Short/Long Posterior Ciliary Arteries (all)
• Short Posterior Ciliary Arteries (15-20)

Question 2

Name 2 structures the central retinal artery supplies. Be specific.

Answer 2

1. Central part of the optic nerve from point of entry to posterior border of lamina cribosa
2. Inner layers of the retina (up to OPL)

Question 3

The superior vortex veins drain directly into the

Answer 3

Vortex veins of the superior side of the eye empty directly into the superior ophthalmic vein

Question 4

The central retinal vein drains directly into _____ or ______

Answer 4

The superior ophthalmic vein or directly into the cavernous sinus via the superior orbital fissure (SOF)

Question 5

The anterior ciliary arteries are direct branches of the ______

Answer 5

7 muscular arteries supplying the rectus muscles (a pair for each rectus muscle except for Lateral Rectus having one)

Question 6

The lateral palpebral artery is a direct branch of the _______

Answer 6

Lacrimal artery (which first supplies the lacrimal gland then pierces the orbital septum, then terminates as the lateral palpebral arteries)

Question 7

The medial palpebral artery are direct branches of the _______

Answer 7

The 2 medial palpebral arteries are direct branches of of the ophthalmic artery (anterior portion, or dorsonasal artery) just below the pulley for the superior oblique

Question 8

The major arterial circle of the iris is formed by branches of the following arteries:

Answer 8

Long posterior ciliary arteries and anterior ciliary arteries

Question 9

The short posterior ciliary arteries are direct branches of the

Answer 9

Medial and Lateral Posterior Ciliary Arteries (2 total)

Question 10

The long posterior ciliary arteries are direct branches of the

Answer 10

Medial and Lateral Posterior Ciliary Arteries (2 total)

Question 11

While doing a dilated eye exam, you note the following vessel and you realize you are looking at the retina at the equator of the patient’s eyeball

Answer 11

Vortex veins (ampulla)

Question 12

Name 4 vessels that drain directly into the superior ophthalmic vein

Answer 12

Muscular branches (SO, SR, MR, levator)
Supraorbital vein
Supratrochlear vein
Angular vein
Central retinal vein
Lacrimal vein
Ethmoidal vein
Superior vortex veins

(The superior ophthalmic vein then drains directly into the cavernous sinus by passing through SOF above common tendinous ring)

Question 13

The posterior ciliary arteries directly give rise to the following arteries:

Answer 13

Long posterior ciliary artery and around 7-10 short posterior ciliary arteries

Question 14

Blood vessels from these ocular structures drain into the vortex veins

Answer 14

Supplied by long and short posterior ciliary arteries (ocular structures include choroid, ciliary body, iris)

Question 15

(CO) 1. Name the branches of the ophthalmic artery

Answer 15

1. Central retinal artery
2. Lacrimal artery
3. Muscular branches (anterior ciliary)
4. Posterior ciliary arteries (long/short)
5. Supraorbital artery
6. Supratrochlear artery
7. Anterior/Posterior ethmoidal arteries
8. Meningeal artery
9. Medial palpebral artery
10. Dorsal nasal artery

Question 16

(CO) 2. State the direct origin of the medial palpebral and lateral palpebral arteries

Answer 16

(see previous cards)

Question 17

(CO) 3. State the direct origin of the SPCA and LPCA

Answer 17

Medial Posterior Ciliary Arteries

Question 18

(CO) 4. Describe the major parts of the eyeball and/or structures in the orbit supplied by the following arteries

• central retinal artery
• lacrimal artery
• medial palpebral artery
• lateral palpebral artery
• infraorbital artery

Answer 18

Central retinal artery: central part of optic nerve from entry to posterior border of lamina cribosa + inner layers of retina

Lacrimal artery: lacrimal gland

Medial palpebral: medial 1/2 of the upper + lower eyelids and conjunctiva (anastomose with lateral palpebral)

Lateral palpebral (2) : (branch from lacrimal gland) supplies skin and conjunctiva of lateral 1/2 of upper + lower eyelids

Infraorbital: inferior rectus/oblique, lacrimal sac
its extension includes anterior superior alveolar artery supplying maxillary sinus and upper teeth

Question 19

(CO) 5. Describe the path of the short posterior ciliary arteries and what major structures they help supply

Answer 19

“The 15-20 SPCA pierce back of the eyeball in a ring around the optic nerve and run forward in the space between the sclera and the choroid aka suprachoroidal space”

• Helps supply sclera
• Some supply posterior portion of choroid up to equator
• Others anastomose in sclera as circle of Zinn-Haller to supply laminar part of optic nerve

Question 20

(CO) 6. Describe the path of the long posterior ciliary arteries (and their recurrent branches) and what major structures they help supply

Answer 20

“Like the SPCA, the two LPCA pierce the sclera at the back of the eyeball and run forward in the space between the sclera and choroid.. to the ciliary body.”

• Helps supply sclera
• In ciliary body, anastomose together and with anterior ciliary to form DISCONTINUOUS arterial ring (major arterial circle of the iris) to supply iris and ciliary body
• 3-5 RECURRENT BRANCHES at ora serrata pass directly back to supply choroid anterior to equator

Question 21

(CO) 7. Describe the path of the anterior ciliary arteries (and their recurrent branches) and what major structures they help supply
-state the direct origin of the anterior ciliary arteries

Answer 21

“Originate from muscular arteries (7) supplying four rectus muscles. After supplying the muscles, the muscular arteries continue anteriorly as anterior ciliary arteries, passing forward and bifurcating so that some branches continue forward beneath bulbar conj., others pierce sclera, become part of MACOTI in CB”

-RECURRENT BRANCHES (8-12) pass directly back to supply choroid anterior to equator

Question 22

(CO) 8. Describe what arteries supply the:

• choroid (including choroid anterior to equator vs. posterior to equator)
• central part of optic nerve behind the lamina cribosa
• laminar part of the optic nerve
• inner retinal layers
• iris
• ciliary body
• sclera
• eyelids

Answer 22

Choroid: anterior (Long Posterior Ciliary Arteries (2) at the Ora Serrata (and recurrent branches of anterior ciliary) (7)), posterior (Short Posterior Ciliary Arteries (15-20)

Central part of optic nerve behind lamina: Central retinal artery

Laminar part of optic nerve: Short Posterior Ciliary Arteries (15-20)

Inner Retinal layers: Central retinal artery

Iris/Ciliary Body: Long Posterior Ciliary Arteries (2) + Anterior Ciliary Arteries (7) (as part of MACOTI)

Sclera: Short/Long Posterior Ciliary Arteries (all)

Eyelids: Medial/Lateral Palpebral Arteries

Question 23

(CO) 9. Discuss the major veins of the eye and orbit discussed in class (central retinal vein, superior ophthalmic vein, inferior ophthalmic vein, vortex veins) in terms of:

• vessels and or structures they receive blood from (omit muscular veins)
• what venous structure they drain directly into, including associated foramina used to exit the orbit

Answer 23

Central Retinal Vein

• drains capillaries supplying inner layers of the retina
• drains into superior ophthalmic vein or directly into cavernous sinus via SOF

Superior Ophthalmic Vein

• drains blood from muscular branches (SO, SR, MR, levator palpebrae), supraorbital/supratrochlear/angular/central retinal/lacrimal/ethmoid veins and superior vortex veins (choroid)
• drains directly into the cavernous sinus through SOF above common tendinous ring

Inferior Ophthalmic Vein

• drains blood from muscular branches (IR/IO/LR), angular/inferior vortex veins, inferior conjunctiva and lacrimal sac
• drains directly to cavernous sinus passing through SOF below common tendinous ring and the pterygoid venous plexus via IOF

Vortex Veins

• drains areas supplied by long and short posterior ciliary arteries including choroid, CB, iris
• drain into superior/inferior ophthalmic vein

Question 24

(CO) 10. Describe what the vortex vein ampulla is and what anatomical part of the eyeball it is a landmark for when seen during a dilated examination of the retina

Answer 24

.The “ampulla” of a vortex vein is the dilated beginning of the vortex vein readily visible on a dilated patient (with BIO)

• choroidal veins drain into the ampulla
• vortex ampulla is located at the equator of the eyeball (vortex veins exit eyeball 6mm posterior to equator)

Question 25

(CO) 11. State which ocular structures’ blood vessels drain into the vortex veins

Answer 25

LPCA, SPCA, choroid, portions of CB and iris