Eye - Neurovasculature Flashcards
Where do CN3, 4,6 enter the orbit?
Superior orbital fissure
What branches of the trigeminal nerve enter the orbit?
Maxillary and ophthalmic
What allows sensory innervation of the eye?
V1 and V2
What does the ophthalmic nerve innervate of the orbit?
Upper eyelid
Upper part of eyeball
Where does V1 enter the orbit?
Superior orbital fissure
What type of sensation does V1 supply to the orbit/eye?
General sensation
Where does V2 enter the orbit?
Inferior orbital fissure and a small branch called the infra-orbital nerve leaves to come out through the Infraorbital formamen
What are the 3 branches of the ophthalmic division?
Nasociliary
Lacrimal
Frontal
What blood vessel does the ophthalmic artery arise?
Internal carotid artery
What artery supplies all of the orbit and its contents?
Ophthalmic artery
What does the ophthalmic artery divide into?
What structures pass through the optic foramen?
Ophthalmic artery and optic nerve
Name branches of the ophthalmic artery
1 = opthamic artery
2 = central retina, artery
3, 4,5 = short posterior ciliary arteries
6 = long posterior ciliary arteries
7,8 = anterior and posterior ethmoidal arteries
9 = muscular arteries
What artery accompanies the optic nerve into the eyeball?
Central artery
What does the central retina, artery supply?
Inner layers of the retina
What do the short posterior ciliary arteries supply?
Posterior part of the choroid (and outer retina)
What does the long posterior ciliary arteries supply?
Anterior choroid, ciliary body, iris
What arteries supply in the inside vs outside of the retina?
Inner = central retina artery
Outer = choroid, which is in turn supplied. Y the short posterior ciliary arteries
What eye is shown?
Left
What is the black arrow pointing to?
Optic disc - start if the optic nerve, physiological blind spot
What branches are the veins?
The thicker branches
When does the central retina, artery split into 4?
When it reaches the optic disc
What are the 4 branches of the central retinal artery?
What are the nasal aspects of the eye? What artery lie on this side?
Superonasal
Inferonasal
What is the temporal region of the eye and what nerves lie here?
Superotemporal
Inferotemporal
Where do the veins from the eye drain to?
Inferior and superior ophthalmic veins
What fissure do the ophthalmic veins pass through?
Superior orbital fissure
Where do the ophthalmic veins drain into?
Cavernous sinus
What is the cavernous sinus?
One of the venous sinuses inside the cranial cavity
What space in the skull is the venous drainage located?
Dura mater layer
Intracranial venous sinuses
What vein do the intracranial dural venous sinuses drain into?
Internal jugular vein
What venous sinus drains the orbit?
Cavernous sinus
What is the importance of the cavernous sinus clinically?
The cranial nerves that have to go into the orbit through the superior orbital fissure have to all pass through the walls soft the cavernous sinus
3,4,6 and loops of carotid artery
E.g. fistula, and orbit does not get enough blood supply
Infection of sinuses, venous drainage from orbit is impeded
