Opthalmology

Question 1

What are the bones of the bony orbit?

Answer 1

Orbital plate of frontal 
Orbital plate of ethmoid
Maxilla 
Zygoma 
Lacrimal 
Sphenoid

Question 2

What are the 2 foramen of the bony orbital?

Answer 2

Supraorbial notch / foramen

Infraorbital foramen

Question 3

What are the orbital margins of the base of the bony orbit called?

Answer 3

Medial wall
Lateral wall
Floor (inferior) wall 
Roof (superior) wall
Apex (optic canal) wall

Question 4

What is another name for the base of the bony orbit?

Answer 4

Orbital rim

Question 5

What part of the bony orbit is the thinnest?

Answer 5

Medial wall

Question 6

Which wall of the bony orbit is most commonly fractured?

Answer 6

Inferior

Question 7

What is the main muscle of the eye and what two parts is it composed of?

Answer 7

Orbicularis Oculi

composed of i) orbital part ii) palpebral part

Question 8

What are the two ligaments of the orbital septum?

Answer 8

Lateral and medial palpebral ligaments

Question 9

What is the main tendon of the orbital spetum?

Answer 9

Tendon of levator palpebrae superioris

Question 10

What is the orbital septum composed out of?

Answer 10

Connective tissue

Question 11

Where are the tarsal glands situated?

Answer 11

In the inferior and superior tarsus

Question 12

What is the function of the orbital septum?

Answer 12

Surrounds periorbital fat and helps stop of spread of infection form superior and deep aspect

Question 13

What do the tarsal gland secrete?

Answer 13

Lipids

Question 14

What is the junction between the cornea and sclera called?

Answer 14

The Limbus

Question 15

What nerve innervates the lacrimal gland?

Answer 15

CN VII

Question 16

What is the path of lacrimal fluid drainage?

Answer 16

Lacrimal Puncta –> Canaliculi –> lacrimal sac –> nasolacrimal ducts –> inferior meatus

Question 17

What are the 3 main layer of the eye?

Answer 17

Fibrous
Uvea
Retina

Question 18

What does the fibrous layer contain?

Answer 18

Sclera

Cornea

Question 19

What does the uvea layer contain ? (vascular layer)

Answer 19

Iris 
Ciliary body (controls iris, shape of lens and secretion of aqueous humour) 
Choroid (Nutrition and exchange)

Question 20

What two chambers is the anterior segment composed of?

Answer 20

Anterior and posterior chamber

Question 21

Where is the anterior chamber and what does it contain?

Answer 21

Between cornea and iris

contains aqueous humour

Question 22

Where is the posterior chamber and what does it contain?

Answer 22

Between iris and suspensory ligaments

Contains aqueous humour

Question 23

What does the posterior segment contain?

Answer 23

Vitreous humour

Question 24

What anatomical structure on the surface of the eye shows where the anterior chamber is?

Answer 24

Iridocorneal angle

Question 25

What is the circulation of the aqueous humour?

Answer 25

Ciliary body --> posterior chamber --> pupil --> scleral venous sinus (canal of schlemm) at iridocorneal angle

Question 26

What are the 3 main components of the fundus?

Answer 26

Optic disc Macula Fovea

Question 27

What is the fovea?

Answer 27

The centre of the macula, area of the most acute vision

Question 28

From posterior to anterior, what are the layers of the retina?

Answer 28

Photoreceptors Ganglion cells Axons of ganglion cells

Question 29

What is the arterial supply to the eye?

Answer 29

Internal carotid --> opthalmic --> central retinal artery

Question 30

What vein is the only vein draining the retina?

Answer 30

Central retinal vein

Question 31

What is the "Danger Triangle"?

Answer 31

Area from upper lip to external nose where it is easy to pierce a superficial vein. Infection can get in here and theoretically the infection can get to the brain through lack of valves

Question 32

What are the extrocular muscles of the eye?

Answer 32

``` Superior rectus Inferior rectus Medial rectus Lateral rectus Superior oblique Inferior oblique Levator palpebrae superioris ```

Question 33

Where does the extraocular muscles of the eye attach to?

Answer 33

The sclera

Question 34

What is the function of the levator palpebrae superioris?

Answer 34

Lifts the upper eyelid

Question 35

What is the mnemonic about nerve supply to the extramuscles of the eye?

Answer 35

LR6 SO4 AO3

Question 36

What extraocular muscles does the aducens nerve supply?

Answer 36

Lateral rectus

Question 37

What extraocular muscles does the trochlear nerve supply?

Answer 37

Superior oblique

Question 38

What extraocular muscles does the oculomotor nerve supply?

Answer 38

``` Medial rectus Superior rectus Inferior rectus Inferior oblique Levator palpebrae superioris ```

Question 39

What are the 4 axis of movement of the eye?

Answer 39

Vertical axis Transverse axis Anteroposterior axis apex of orbit

Question 40

Most extraocular muscles have secondary muscles, but two of them do not. What are the 2 muscles?

Answer 40

Medial and lateral rectus

Question 41

What is the primary function does the lateral rectus have?

Answer 41

Adduction of eyeball

Question 42

What is the primary function of the superior oblique?

Answer 42

When in abduction, can only elevate

Question 43

What is the primary function of the inferior rectus?

Answer 43

When in abdution, can only depress

Question 44

What is the primary function of the medial rectus?

Answer 44

Adduct eye ball, bring nose toward the nasal cavity

Question 45

What is the primary function of the inferior oblique muscle?

Answer 45

When in adduction, can only elevate

Question 46

What is the primary function of the superior oblique?

Answer 46

When in adduction, can only depress

Question 47

What muscles contribute towards "Pure Elevation"?

Answer 47

Superior rectus and Inferior oblique

Question 48

What muscles contribute toward "Pure Depression"?

Answer 48

Inferior rectus and the superior oblique