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Ophthalmology Week 1 2017/18 > 10: Anatomy - clinical > Flashcards

Flashcards in 10: Anatomy - clinical Deck (89)
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1
Q

How wide is the eye in diameter?

A

2.5 cm

2
Q

Which eyelid is the most important one clinically?

A

Upper eyelid

Lower eyelid has very little function in comparison

3
Q

Which type of gland is found within the tarsal plates and releases an oily substance which stops the tear film from evaporating?

A

Tarsal gland

or Meibomian gland

4
Q

What muscles open the upper eyelid?

A

Levator palpebrae superioris

AND

Mueller’s muscle

5
Q

Which type of fibres innervate Mueller’s muscle so it can help levator palpebrae superioris with opening the upper eyelid?

A

Sympathetic

6
Q

Which cranial nerve innervates levator palpebrae superioris?

A

CN III

7
Q

What is the function of orbicularis oculi?

Which cranial nerve supplies it?

A

Closes the eyelids

CN VII (remember it’s a muscle of facial expression)

8
Q

Which part of orbicularis oculi is responsible for blinking?

A

Palpebral part

9
Q

What are the three main symptoms of Horner’s syndrome?

A

Miosis (constricted pupil)

Ptosis (droopy eyelid)

Anhidrosis (lack of sweating)

unilaterally

10
Q

What lung tumour can cause Horner’s syndrome by compressing the superior cervical ganglia?

A

Pancoast tumour

11
Q

What is the purpose of the orbital septum?

A

Prevents transmission of pathogens/debris etc. into bony orbit

12
Q

What is an infection of the orbit which is sight and life-threatening and must be treated immediately?

A

Orbital cellulitis

13
Q

What does orbital cellulitis look like?

A

Puffy inflamed eye

Fever

Rigors

Pupillary disorders

14
Q

Where in the orbit is the lacrimal gland found?

A

Superolaterally

15
Q

Where are the Meibomian glands found?

A

Tarsal plates

16
Q

Lacrimal fluid is swept from the ___ to ___ sides of the eye.

A

temporal to nasal

17
Q

What is the function of the Meibomian glands?

A

Add oil to tear film to stop it from evaporating

18
Q

Through which structures does lacrimal fluid enter the superior and inferior lacrimal papillae?

A

Puncta

19
Q

What carries lacrimal fluid from the lacrimal sac to the nose?

A

Nasolacrimal ducts

20
Q

What symptom may be produced by a blind-ended lacrimal sac?

A

Watery eyes

which AREN’T red (no inflammation)

21
Q

Which type of weather dries out the eyes?

What symptom does this lead to?

A

Cold weather

Watery eyes - reflex lacrimation overcompensates

22
Q

Which cranial nerves control the

a) sensory
b) motor parts of reflex lacrimation?

Is this sympathetic or parasympathetic?

A

a) CN V1

b) CN VII

Parasympathetic

23
Q

Why do people with uncontrolled diabetes develop corneal ulcers?

A

Neuropathy

CN V1 doesn’t detect dryness

So reflex lacrimation doesn’t occur

So cornea dries out and ulcerates

24
Q

Which enzymes are found in the tear film and give it antibacterial properties?

A

Lysozymes

25
Q

Which types of conjunctiva line

a) the sclera of the eyes
b) the inner surface of eyelids?

What are the folds which form when these two types make contact?

A

a) Bulbar conjunctiva

b) Palpebral conjunctiva

Conjunctival fornix

26
Q

The palpebral conjunctiva lines the ___.

The bulbar conjunctiva lines the ___.

A

inner eyelid

sclera

27
Q

Which type of conjunctiva is more vascular?

A

Palpebral conjunctiva

28
Q

What can be seen on the palpebral conjunctiva?

A

Follicles

Papillae

29
Q

What does

a) bacterial

b) viral

conjunctivitis look like?

A

a) Pus, red eye

b) Watery, pink eye

30
Q

Viral conjunctivitis commonly accompanies which type of infection?

A

URTI

31
Q

Which lymph nodes may be enlarged in conjunctivitis?

A

Pre-auricular lymph nodes

32
Q

Conjunctivitis is highly ___.

A

contagious

33
Q

Follicles may be seen on the inner eyelid in which types of infection?

A

Bacterial - esp. chlamydia

Viral

34
Q

Papillae are commonly seen on the inner eyelid in ___ reactions.

A

allergic

35
Q

What percentages of total refractive power do the

a) cornea

b) lens

have?

A

a) 2/3rds

b) 1/3rd

36
Q

The epithelium of the cornea (regenerates / can’t regenerate) and has loads of nerve endings.

A

epithelium regenerates

37
Q

What is the endothelium of the cornea like?

Does it regenerate?

A

Single layer of cells

Doesn’t regenerate

38
Q

What disease causes the cornea to bulge into a cone shape and causes visual disturbance?

A

Keratoconus

39
Q

The anterior surface of the lens is ___.

The posterior surface of the lens is ___.

A

anterior surface is FLAT

posterior surface is CURVED

40
Q

What disease causes the lens to become yellow and difficult to see through?

A

Cataracts

41
Q

How are cataracts treated?

A

Implant artificial lens

42
Q

Which muscles control the shape of the lens?

A

Ciliary muscles

43
Q

Sympathetic stimulation causes:

ciliary muscles to CONTRACT / RELAX

the lens to FLATTEN / BULGE

NEAR SIGHT / FAR SIGHT

A

Sympathetic:

ciliary muscles RELAX

lens FLATTENS (to be CONCAVE)

FAR SIGHT

44
Q

Parasympathetic stimulation causes:

ciliary muscles to CONTRACT / RELAX

lens FLATTENS / BULGES

NEAR SIGHT / FAR SIGHT

A

Parasympathetic:

ciliary muscles CONTRACT

lens BULGES (to be CONVEX)

NEAR SIGHT

45
Q

What structures are in the vascular layer (uvea)?

A

Iris

Ciliary body

Choroid

46
Q

The choroid supplies ___ to the other layers of the uvea.

A

nutrition

47
Q

The uvea is ___ to help with light capture.

A

pigmented

48
Q

Where is aqueous fluid produced?

Where can it be reabsorbed from?

A

Ciliary body

Bloodstream

49
Q

What colour is aqueous fluid?

A

Transparent

50
Q

Aqueous fluid has a (high / low) protein content.

A

low protein content

so it can be transparent to see through

51
Q

Why might the aqeuous fluid become hard to see through?

A

Uveitis - full of floating inflammatory cells

Treat with steroids

52
Q

Aqueous fluid is produced by the ___ ___, fills the (anterior / posterior) chamber and then drains where?

A

ciliary body

anterior chamber

iridocorneal angle

53
Q

The iridocorneal angle is found at the (superior / inferior) part of the cornea.

A

superior

54
Q

What is the normal range of intraocular pressures?

A

12 - 22 mmHg

55
Q

In which disease is intraocular pressure raised?

A

Glaucoma

56
Q

What is the path that nerve impulses take in the pupillary light reflex?

A

Optic nerve

Optic chiasm

Optic tract

Optic radiation

Pretectal nucleus of visual cortex

EW nucleus

Short ciliary nerve

Sphincter pupillae

57
Q

Once they have come off the spinal cord at L2, how do sympathetic nerves reach the eye?

A

Sympathetic chain

Superior cervical ganglia

Internal carotid artery

Ophthalmic artery

Long ciliary nerves

Dilator pupillae

58
Q

What is the accommodation reflex?

A

Eyes focus on object coming towards you in the midline

59
Q

Which three actions allow for the accomodation reflex and which muscles control them?

A

1. Adduction of eyes by medial rectus (CN III)

2. Constriction of pupils by sphincter pupillae

3. Flattening of lens by ciliary muscles

60
Q

What is myopia?

A

Short sightedness

61
Q

What causes myopia?

A

Eye is too wide so light isn’t focused onto retina correctly

62
Q

Myopia (short sightedness) increases your chances of what?

A

Retinal detachment

63
Q

Which extraocular muscles does CN III control?

A

Medial rectus

Superior rectus

Inferior rectus

Inferior oblique

Levator palpebrae superioris

64
Q

What sort of eye movement does a CN III palsy cause?

A

DOWN AND OUT

because lateral rectus (abduction) and superior oblique (depression) are the only muscles still working

65
Q

What sort of eye movement problems does CN IV palsy cause?

A

UP AND IN

with a head tilt required to see properly

66
Q

What might a person with CN IV palsy have trouble doing?

A

Walking down stairs

due to diplopia (double vision), they can’t look down properly

67
Q

CN IV palsy produces symptoms in the (ipsilateral / contralateral) eye.

A

contralateral eye

because they arise from the brainstem and then cross over

68
Q

What does CN V1 supply?

A

Forehead

Upper eyelid

Eye

TIP OF NOSE

69
Q

What is a sign that ophthalmic zoster may affect the cornea?

A

Hutchison’s sign

Rash on tip of nose (which is supplied by CN V1)

70
Q

Why do people with viral keratitis have dendritic ulcers?

A

Virus tracks along CN V1

71
Q

What eye movement does CN VI palsy cause?

A

Medial squint

because CN VI supplies lateral rectus only

72
Q

What is the common origin for all the extraocular muscles?

A

Common tendinous ring

73
Q

The common tendinous ring is part of the sheathe for which nerve?

A

Optic nerve

74
Q

What nerve problem causes pain on eye movement?

A

Optic neuritis

because common tendinous ring is part of nerve sheathe

75
Q

What type of fracture can trap inferior rectus?

A

Orbital blowout fracture

76
Q

How would a suspected orbital blowout fracture be investigated?

A

CT head

because CT is good for bones

77
Q

An orbital blowout fracture can breach which wall of the bony orbit?

What is a complication of this?

A

Medial wall

Transmission of bacteria into maxillary sinus > meningitis

78
Q

Where in the retina are

a) rods
b) cones found?

A

a) Rods - peripheral

b) Cones - central (macula/fovea)

79
Q

Which type of photoreceptor is good for detecting movement?

A

Rods

high sensitivity (see other lectures)

80
Q

Where exactly is the blind spot?

A

15 degrees temporal from centre

81
Q

What does someone mean when they say the retina is inverted?

A

Light passes through the blood vessels, ciliary axons / ganglia to reach the photoreceptors

Then the nerve impulses travel anteriorly through all that to the optic nerve

82
Q

What are the end arteries of the eye?

A

Central artery of the retina

(ophthalmic artery)

83
Q

What do veins look like through an ophthalmoscope?

A

Thick and dark

because they have no muscle

84
Q

What do arteries look like through an ophthalmoscope?

A

Thin, tubular, lighter

because they have muscular walls

85
Q

What are the 3 Cs to look for when describing the optic disc?

A

CUP - inner ring (like a donut)

COLOUR - should be pink/orange

CONTOUR - should be well-defined

86
Q

What colour does the

a) whole fundus
b) fovea

turn in a central retinal artery occlusion?

A

a) Milky white

b) Cherry red / black

87
Q

Where does

a) CN III, IV and VI enter the orbit
b) the superior ophthalmic vein exit the orbit?

A

Superior orbital fissure

88
Q

Where do the ophthalmic veins drain after exiting the bony orbit?

A

Cavernous sinus

89
Q

What does the fundus look like in a central retinal vein occlusion?

A

Pizza