Eye and Orbit

Question 1

What is the cutaneous innervation of the eyelid?

Answer 1

V1 -Supraorbital -Supratrochlear -Infratrochlear -Lacrimal V2 -Infraortibal

Question 2

What is the orbital septa?

Answer 2

Extensions of periostium to form rounded eye shape of eyelids.

Question 3

What is the conjunctiva? Layers?

Answer 3

Thin membrane that protects the eye. -Palpebral layer -Bulbar/ocular layer -Fornical layer

Question 4

What is conjunctivitis?

Answer 4

Infection of conjunctiva

Question 5

Lacrimal gland is divided into two parts by what muscle? Where is lacrimal gland located?

Answer 5

Levator palpebrae superioris. located superior and and lateral to the eye.

Question 6

What are the lacrima puncta, canaliculi, sac, and duct? Where do tears drain?

Answer 6

Puncta=opening to drain Canaliculi: canals to sac Sac: collecting sac Nasoacrimal duct: drains sac. Drains into the inferior meatus

Question 7

lens, pupil, optic nerve, vitreous chamber, canal of schlemm, anterior and posterior chamber.

Answer 7

1. Lens 2. Pupil 3. Anterior chamber -Filled with aqueous humor 4. Posterior chamber -Filled with aqueous humor 5.Canal of Schlemm -Drains aqueous humor 6. Vitreous chamber -Filled with vitreous humor 7. Optic nerve

Question 8

Aqueous humor is made by what? Drains into? Via?

Answer 8

-Made by ciliary body -Drains into superior ophthalmic vein via the Canal of - Schlemm

Question 9

What causes glaucoma?

Answer 9

Intraocular pressure

Question 10

What causes cataracts?

Answer 10

Lens become opaque

Question 11

What are the 3 layers/tunics of they eye?

Answer 11

1. Fibrous 2. vascular or uveal 3. Neural

Question 12

What is contained in the fibrous tunic?

Answer 12

1. Sclera: Whites of eye 2. Cornea 3.Choroid :vascular 4. Ciliary body 5. Suspensory ligaments

Question 13

What is the vascular tunic?

Answer 13

1. Lens 2. iris 3. pupil

Question 14

What is in the neural tunic?

Answer 14

Retina

Question 15

What is emmetropia, myopia, hyperopia, astigmatism, presbyopia?

Answer 15

1. Emmetropia: Normal vision 2. Myopia: Nearsightedness 3. Hyperopia: Farsightedness 4. Astigmatism: Parts of the image focus at multiple locations 5. Presbyopia: Loss of elasticity in the lens

Question 16

What are the 2 parts of the retina?

Answer 16

1. Pigmented: captures light and keeps it from bouncing around the eye. 2. Neural: Contains the photoreceptors, neurons..

Question 17

What do Rods do? Cones?

Answer 17

Rods=Black and white, night and peripheral vision. Cones=Color, daylight, high acuity

Question 18

What is the pathway of light in the retina?

Answer 18

-Rods and cones -Bipolar cells -Ganglion cells -Optic disc -Optic nerve

Question 19

What is the macular lutea, fovea centralis, optic disk?

Answer 19

M: Dense area of mostly cones F: Cones only used for max vision acuity O: Area where optic nerve inserts, no rods or cones.

Question 20

What is visual pigments? Also called? What happens to them with light?

Answer 20

Rhodopsin, also called visual purple. Changes shape with light and causes cascade.

Question 21

What makes rhodopsin? What is synthesized by vitamin A?

Answer 21

Opsin + Retinal=Rhodopsin

Retinal synthesized from Vit A.

Question 22

What is bleaching? Night blindness?

Answer 22

Bleaching=Over stimuli of rhodopsin (camera flash) Night: Deficiency of Vit A

Question 23

What is the whole pathway of light into the eye to the brain?

Answer 23

Cornea, Anterior chamber, lens, Vitreous chamber, retina, cones/rods,bipolar cells, ganglion cells, to optic disk, optic nerve, chiasma, optic tract, thalamus, occipital lobe.

Lateral side stays on same side, medial crosses over at chiasma.

Question 24

What are the bones of the orbit?

Answer 24

FLME SPZ Frontal Lacriaml Maxilla Ethmoid Sphenoid Palatine zygomatic

Question 25

What are the walls of the orbit?

Answer 25

1. Superior
   - Frontal
   - Lesser wing of sphenoid
2. Inferior
   - Maxilla
   - Zygomatic
   - Palatine
3. Medial
   - Ethmoid
   - Lacrimal
   - Frontal
   - Maxilla
4. Lateral
   - Zygomatic
   - Greater wing of the sphenoid
   - Frontal

Question 26

What is the periorbital fascia?

Answer 26

Periosteum of the orbit.

Question 27

What are the contents of the orbit?

Answer 27

• Eye
• Extrinsic muscles
• Cranial Nerves Optic nerve (CNII) Oculomotor nerve (CNIII) Trochlear nerve (CNIV) Ophthalmic nerve (CNV1) Abducens nerve (CNVI)
• Ciliary ganglion
• Ophthalmic artery and branches (from internal carotid artery)
• Superior and inferior ophthalmic veins (draining into cavernous sinus)
• Lacrimal apparatus
• Fatty tissue

Question 28

What are the contents of the superior orbital fissure?

Answer 28

-Superior and inferior branches of CNIII CNIV -Lacrimal branch of V1 -Frontal branch of V1 -Nasociliary branch of V1 -CNVI -Superior ophthalmic vein -Sympathetic fibers from cavernous plexus

Question 29

What are the contents of the optic canal/foramen?

Answer 29

CNII Ophthalmic a.

Question 30

What are the contents of the inferior orbital fissure?

Answer 30

-Inferior ophthalmic vein -Infraorbital branch of V2 -Zygomatic branch of V2 -Ascending branches of pterygopalatine ganglion -Infraorbital vessels

Question 31

What is the common tendinous ring? Contents? Covered in?

Answer 31

Tendon ring formed by eye muscles. Covered with fascia bulbi (tenon’s capsule) -CNII -Ophthalmic artery -Superior and inferior branches of CNIII -Nasociliary branch of V1 -CNVI

Question 32

What is the arterial supply of the orbit? Where do the ophthalmic and central retina travel?

Answer 32

• Ophthalmic a (lateral and inferior to optic nerve)
• Lacrimal a. Supply lacrimal gland
• Supratrochlear a. Supply orbit -Supraorbital a. Supply orbit
• Anterior ethmoid a. Supply nasal cavity
• Posterior ethmoid a. Supply nasal cavity
• Dorsal nasal a. Supply nasal cavity
• Long and short posterior ciliary aa. Supply sclera
• Central retinal a. Travels with optic nerve Supply retina