Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Duke Elder > Eyelids > Flashcards

Eyelids Flashcards

1
Q

Layers of the eyelid (anterior to posterior)

A

Skin
Orbicularis muscle
Tarsal plate (fibrous)
Levator muscle
Muller muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Lamellae of the eyelids

A

Anatomically divided into 2 lamellae by the Gray line (outermost margin of the Orbicularis muscle)

  • Anterior lamella contains: skin and orbicularis
  • Posterior lamella contains: tarsal plate and conjunctiva
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Landmarks of upper vs lower lid

A

Normally, the upper lid is 2mm below the superior limbus and the lower lid is at the level of the inferior limbus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What forms the tarsal plates?

A

The orbital septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What maintains the shape of the eyelids?

A

The tarsal plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How can depth of an eyelid laceration be catagorised?

A

Layer of preaponeurotic fat pads just posterior to the orbital septum

If the fat pads are visible then it is a deep laceration involving the posterior lamella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What landmarks differentiates orbital vs pre-orbital cellulitis

A

The orbital septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Muscles which cause retraction of eyelid

A
  1. The levator innervated by CN3
  2. Frontalis (muscle of facial expression) innervated by CN7
  3. Muller’s muscle under sympathetic innervation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Main muscle of eyelid closure?

A

Orbicularis oculi innervated by CN7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What muscles has an important role in the lacrimal pump mechanism

A

Orbicularis oculi - its action guides the flow of tears across the ocular surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Blink reflex

A

Afferent Limb (3 inputs paths)
* Corneal stimulus via CNV1
* Light stimulus via CN2
* Auditory stimulus via CN8

Efferent limb (1 effector path)
Via CN7 to the Orbicularis oculi muscle, which controls lid closure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Bell’s phenomenon?

A

Normal physiological finding where the globe rotates up and out during forced lid closure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Poor Bell’s phenomenon?

A

Is a risk factor for lagophthalmos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the Canthal tendons?

A
  • The canthal tendons keep the eyelid structure stable
  • 2 in each orbit: medial and a lateral
  • Attach to the tarsus of the upper and lower eyelids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Anatomical location of the lacrimal sac?

A

The lacrimal sac lies between the limbs of the medial canthal tendon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the palpebral fissure?

A

The gap between the upper and lower eyelid margins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Thyroid eye disease and the eyelid

A

Retraction
Muller contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Horner syndrome and the eyelid

A

Ptosis
Muller relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

CN7 palsy and the eyelid

A

Lagophthalmos due to Orbicularis spasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

CN3 palsy and the eyelid

A

Ptosis
Levator relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is Lagophthalmos?
Why is it dangerous?

A

Inability to fully close the eyelids (palpebral fissure)

Leads to exposure keratopathy, which can be sight-threatening.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Types of lid reconstruction

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Can both lamellae be repaired with grafts?

A

No because there would be no blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is the anterior lamella reconstructed?

A

Anterior advancement → incise and stretch tissue over the laceration
Transposition → move tissue from the other lid
Rotation → rotated skin from the cheek
Glabella → rotated diamond-shaped forehead skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is the posterior lamella reconstructed?

A

Hughs Flap → flap taken from the upper lid
Free tarsal graft from the fellow eye → tissue taken from the other eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In a full-thickness laceration of the lid, which lamella is reconstructed first?

A

The posterior lamella is repaired before the anterior lamella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Blepharitis

A

Chronic inflammation of the eyelid of any cause.

Typically associated with Staphylococcus aureus infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Classification of Blepharitis

A

Anterior - Affects the base of the eyelashes
2 further subtypes:
* Seborrhoeic (excessive secretions)
* Staphylococcal (direct infection)

Posterior - Affects the Meibomian glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Does anterior or posterior blepharitis have a better response to treatment?

A

Anterior, because it occurs at the surface level.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Blepharitis presentation

A

Bilateral crusting of the lids and lashes
Foamy tear film and meibomian cysts are seen specifically with posterior blepharitis.
The lashes can appear normal in posterior blepharitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Unilateral blepharitis must be investigated for what?

A

Sebaceous cell carcinoma!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Atopic dermatitis is associated with what type of blepharitis

A

Staphylococcal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Seborrheic dermatitis is associated with what type of blepharitis

A

Seborrheic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Acne rosacea is associated with what type of blepharitis

A

Posterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Management of blepharitis

A

Lid hygiene
Warm compress
Topical lubrication and tetracyclines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How do tetracyclines treat blepharitis?

A

limit fatty acid production which can decrease the inflammatory secretions

37
Q

Meibomian Gland Dysfunction

A

chronic disorder of the meibomian glands that overlaps with posterior blepharitis. It is characterised by duct obstruction and abnormal glandular secretions, which result in a characteristically foamy tear film

38
Q

Pathology of MGD

A

Secretion of the meibomian oil is obstructed → stagnation within glands → inflammation →staphylococcal colonisation → chronic inflammation and scarring

39
Q

Function of meibomian glands

A

Secrete a lipid layer which contributes to the tear film.

Functions of this layer is to help keep the tear film stable

40
Q

What is Meibomianitis?

A

Type of MGD where inflammation is marked

It is associated with acne rosacea and worse in the mornings with thick secretions and duct inflammation

41
Q

Presentation of MGD

A

Foamy tear film
Crusty eyelashes
Gritty irritated eyes

42
Q

Investigations for MGD

A
  • Tear film breakup time of <5 seconds is a sign of tear film instability
  • Fluorescein staining of the cornea shows corneal epithelial damage
43
Q

Management of MGD

A

Determined by clinical classification

44
Q

Untreated MGD can lead to?

A

MG cysts, trichiasis, blepharitis, and keratitis

45
Q

What is Trichiasis?

A

Trichiasis is the inward misdirection of the eyelashes. This can lead to corneal irritation and ulceration.

46
Q

Distichiasis

A

A congenital abnormality where there are 2 rows of eyelashes. Can be associated with Meige syndrome

47
Q

Acquired metaplastic lashes

A

Abnormally positioned lashes due to inflammation such as meibomitis and scarring

48
Q

Pseudotrichiasis

A

Inwardly projecting lashes due to entropion

49
Q

Types of Trichiasis?

A

Distichiasis
Acquired metaplastic lashes
Pseudotrichiasis

50
Q

Management of Trichiasis

A

Epilation - Recurrence is common so this is a temporising measure
Lash destruction by electrolysis/laser/cryotherapy - typically used when there is only a limited collection of abnormal lashes. Scarring and inflammation can be worsened.
Surgery - A pentagon excision can be used to remove focal groups of lashes.

51
Q

How are benign lid lumps classified?

A

Based on location: anterior or posterior lamella

52
Q

Hordeolum (stye)

A

A painful lid abscess caused by Staphylococcus infection.

53
Q

Hordeolum classification

A

External (anterior lamella): abscess of Zeis or Moll glands

Internal (posterior lamella): abscess of Meibomian glands

54
Q

Presentation of hordeolum

A

Painful nodule
Commonly affects the upper eyelid
Diagnosis is clinical

55
Q

Management of hordeolum

A

Hot compress
Oral antibiotics

56
Q

Key difference between Hordeolum vs chalazion

A

chalazion is a painless nodule

57
Q

Pathology of Chalazion

A

Obstruction of Meibomian or Zeis glands leads to sterile lymphogranuloma formation

58
Q

Presentation of chalazion

A

Painless upper eyelid nodule

59
Q

Management of chalazion

A

Hot compress is the only management that is usually required
Surgical incision and curettage is an option but rarely needed

60
Q

Anterior Lamella Cysts

A

Cyst of Moll and Cyst of Zeis are chronic benign anterior lamella cysts.

They are often self-limiting but can be excised or treated with diathermy

61
Q

Compare a cyst of Moll vs Zeis

A

Cyst of Moll - chronic translucent cyst arising from blockage of Moll glands

Cyst of Zeis - chronic non-translucent cysts arising from blockage of Zeis glands

62
Q

commonest cancer in ophthalmology

A

Basal Cell Carcinoma

63
Q

Basal Cell Carcinoma features

A
  • Most commonly occurs on lower lid of eye and upper lip of the mouth
  • It is a slow-growing lesion and does not typically spread
  • The lesion is pearly white with associated telangiectasia
64
Q

BCC management

A

Surgical resection
Mohs Micrographic surgery can for used in high-risk cases where the lesion margins are uncertain

65
Q

What is Vismodegib?

A

Vismodegib is a medication approved for non-resectable cases and works through the Hedgehog pathway.

BCC is associated with Ptch/Smo gene mutation in the Hedgehog pathway

66
Q

Squamous Cell Carcinoma is associated with what two populations?

A

HPV and immunocompromise

67
Q

Pathology of SCC

A

Aggressive and spreads via lymphatics
Histology shows epidermal proliferation, atypical keratinocytes, and squamous eddies

68
Q

Management of SCC

A

Surgical excision, radiotherapy, chemotherapy

69
Q

Melanoma pathology

A
  • Melanoma is not always pigmented.
  • Most likely to arise from the choroid inside the eye (highest concentration of melanin)
  • Spreads to the liver
  • Breslow thickness is the prognostic indicator
70
Q

Melanoma management

A

Surgical excision, radiotherapy, chemotherapy

71
Q

What is vemurafenib

A

Vemurafenib is a kinase inhibitor with FDA approval for unresectable melanomas

72
Q

Sebaceous Gland Carcinoma arise from?

A

Meibomian and Zeis glands

73
Q

Pathology of Sebaceous gland carcinoma

A

Can be misdiagnosed as unilateral blepharitis.
Spreads to lymph nodes and viscera
Associated with Muir Torre syndrome

74
Q

Management of Sebaceous gland carcinoma

A

Surgical excision, radiotherapy, chemotherapy
Prognosis is poor

75
Q

Entropion and ectropion most commonly affect which lid?

A

lower eyelids

76
Q

Ptosis most commonly affects which lid?

A

upper eyelids

77
Q

Ectropion

A

Outwardly pulled eyelid. It can stop the eyes from closing properly (lagophthalmos).

This can compromise the tear film and cause ocular surface irritation.

78
Q

Types of ectropion

A
79
Q

Most common type of ectropion

A

Involutional - Caused by horizontal lid laxity and often seen in the elderly

80
Q

Management of ectropion

A

Depends on the mechanism of ectropion:

Horizontal lid laxity → lateral tarsal strip
Vertical lid laxity → Diamond excision
Cicatrix → skin gaining procedures such as grafts and flaps

81
Q

Entropion

A

Entropion is an inwardly rolled eyelid. It can lead to corneal ulceration as the inwards turning eyelashes rub against the cornea whilst blinking.

82
Q

Types of Entropion

A
  1. Involutional (Commonest type) - caused by lower retractor weakness/dehiscence.
  2. Cicatricial - caused by shortening of the posterior lamella by vertical scarring.
    Most commonly caused by trachoma (upper lid)
83
Q

Management of Entropion

A

Depends on the mechanism of entropion

Retractor weakness → Everting sutures, transverse tarsotomy, or Jones procedure
Scarring → Membrane graft or posterior lamella reconstruction
Botox can be used to weaken overactive muscles

84
Q

Ptosis

A

An abnormally droopy upper eyelid. It can be congenital but is most commonly acquired.

85
Q

Types of ptosis

A

Involutional (commonest)
Neurogenic
Congenital Ptosis
Pseudoptosis

86
Q

Involutional ptosis

A

The most common type.
Caused by dehiscence of the levator palpebrae superioris from its attachment to the levator aponeurosis.
Risk is increased with age and after surgery.
Treatment → anterior levator advancement surgery

87
Q

Neurogenic ptosis

A

CN3 Palsy
* Loss of levator function leads to ptosis.
* Abnormalities in eye movements and a mydriatic pupil can also be seen.
* Spontaneous resolution is common so treatment (with frontalis suspension surgery) is typically delayed

Horner Syndrome
* Surgical management is with Levator resection (strengthens muscle) or Mullerectomy.

Myasthenia Gravis

88
Q

Congenital Ptosis

A

Isolated congenital ptosis
* Developmental myopathy of the LPS
* Typically unilateral, with an absent upper lid crease.
* Treatment depends on levator function:
* Poor function → frontalis suspension.
* Preserved function → anterior levator resection.

Blepharophimosis syndrome
* Characterised by a shortened horizontal palpebral fissure and telecanthus.
* AD inheritance

Marcus Gunn jaw-winking syndrome
* Characteristic elevation of the ptotic lid whilst chewing.
* Thought to be caused by developmental CN5 misdirection to the LPS

89
Q

Pseudoptosis

A

Pseudoptosis is a lid that appears droopy, but is actually within normal range when measured.

Blepharochalasis - abnormally elastic lid tissue leads to excess skin folds and oedema

Dermatochalasis - commonly seen in the elderly. Upper lid skin hangs and folds.

Brow ptosis
Frontalis dysfunction leads to lowering of the entire eyebrow region.

Duke Elder (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions