Eyelids

Question 1

Eyelid Anatomy

Answer 1

Grey line:

• divides lid margin into anterior and posterior parts.
• marginal subcutaneous fibres of orbicularis oculi.
• Anterior: eyelashes (cilia)
• Posterior: orifices of the tarsal (Meibomian) glands
• mucocutaneous junction: behind the orifices of the tarsal glands

Question 2

Diseases of the eyelid

Answer 2

A Infection and inflamation

1. External Hordeolum
2. Internal Hordeolum
3. Chalazion (Meibomian cycst)
4. Chronic Blepharitis
5. Molluscum Contingiosum

B Positional defects

1. Entropion
2. Ectropion
3. Ptosis

C Anatomical defects

1. Dermatochalasis
2. Epicanthus

D Tumors:

1. Xanthelasma
2. Neoplams
   a) Basal cell carcinoma
   b) Squamous cell carcinoma
   c) Tarsal gland (Meibomian) carcinoma
   d) Koposi’s Sarcoma

Question 3

Physiology: Function of lid

Answer 3

The primary purpose of the eyelids is to keep the cornea moist and so maintain its transparency.

Question 4

Anatomy: Eyelid closure

Answer 4

1. Orbicularis oculi,
2. an elliptical sphincter muscle:

facial nerve (VII).

Question 5

Physiology: The oily secretion of the tarsal (Meibomian) sebaceous glands

Answer 5

1. forms a lipid layer on the eyelid margin–> preventing tears from spilling over the edge of the eyelid.
2. forms outer lipid layer of the precorneal tear film which retards the evaporation of tears.

Question 6

Infection and inflammation: EXTERNAL HORDEOLUM (STYE)
GENERAL

Pathophysiology
Presentation
Treatment

Answer 6

PATHOPHYSIOLOGY:
staphylococcal abscess of an eyelash follicle.–> staphylococcal blepharitis (see below).

CLINICAL FEATURES

1. tender
2. inflamed
3. swelling
4. maximal on the eyelid margin–> points anteriorly to the base of an eyelash
5. resolves spontaneously with or without draining onto the skin at the base of the eyelash.

TREATMENT

1. Remove the affected eyelash.
2. Local antibiotic cream.
3. Resolution is accelerated and pain is relieved by warm compresses.

Question 7

Infection and inflammation: INTERNAL HORDEOLUM (MEIBOMIAN ABSCESS)

Pathophysiology
Presentation
Treatment

Answer 7

PATHOPHYSIOLOGY:
staphylococcal abscess of a tarsal (Meibomian) gland.

CLINICAL FEATURES

1. very tender inflamed swelling of the eyelid.
2. area of greatest swelling is away from the eyelid margin.
3. lesion may enlarge and resolve by draining posteriorly through the conjunctiva, or anteriorly through the skin.
4. Occasionally it spontaneously becomes smaller to leave a small, hard nodule in the eyelid, and occasionally it spontaneously becomes quiescent to form a chalazion (see below).

TREATMENT

1. Local antibiotic cream.
2. Systemic antibiotics if severe with surrounding cellulitis.
3. Drainage is indicated when it begins to form a head.

Question 8

Infection and inflammation: CHALAZION (MEIBOMIAN CYST (SIC))

Pathophysiology
Presentation
Treatment

Answer 8

PATHOPHYSIOLOGY
Obstruction of a tarsal (Meibomian) gland duct –> retention of the sebaceous secretions and secondary swelling with low grade inflammation.
It is not a true cyst because the walls consist of granulation tissue and not epithelium.

CLINICAL FEATURES

1. Slowly enlarging round
2. Firm swelling in the eyelid
3. no signs of inflammation such as tenderness or redness of the skin. 4. Occasionally it may develop from an internal hordeolum (see above). 5. Eversion of the eyelid reveals a red, raised area of conjunctiva or a granuloma.

TREATMENT
Incision and curettage:
1. Local anaesthetic: drops and subcutaneous injection.
2. A Meibomian clamp is placed over the lesion and is used to evert the eyelid.
3. A vertical incision is made into the lesion from the conjunctival side.
4. The contents is curetted out with a Meibomian curette.
5. Antibiotic ointment is placed in the conjunctival sac.
6. The eye is covered until the following morning. Give systemic pain relief if needed.
7. Recurrence: Consider tarsal gland carcinoma and obtain a biopsy and histology.

Question 9

Infection and inflammation: CHRONIC BLEPHARITIS

Definition
Cause
Presentation
Complication
Treatment

Answer 9

Definition: An infection of the small glands that line the eyelid margins is known as blepharitis.

Aetiological factors include the following:

1. Staphylococcal infection of the eyelash follicles.
2. Abnormal secretion from the eyelash or tarsal sebaceous glands–> seborrhoeic dermatitis, acne rosacea, atopic eczema and dry eyes.

CLINICAL FEATURES

1. Early: asymptomatic.
2. chronic irritation: burn, scratch and itch.
3. Symptoms often appear to be out of proportion to the findings.
4. Eyelid margin examination hyperaemia with flaking and crusting

COMPLICATION

1. recurrent conjunctivitis
2. internal and external hordeola
3. chalazia.

TREATMENT
1-3 months
1. EYELID HYGIENE
Cleaning of the lids is normally performed with a cotton bud, but if the patient finds this impossible to do, a clean face cloth may be used instead.
Method:
a) Sterilise small container with boiling water
b) Pour 5ml of new boiling water into the container and add 3 drops of Johnson’s Baby Shampoo.
c) Mix the solution with a cotton bud and allow the solution to cool to body temperature.
d) Dip one end of a cotton bud into the solution.
e) work up a lather in the bases of the eyelashes of both upper and lower eyelids with a gentle sideways to and fro motion. NB where the eyelashes come out of the eyelid margin.
f) Repeat the above on the thin edge of the eyelids just behind the point where the eyelashes come out. Done by pulling the eyelid away from the eye: use a finger to put traction on the skin of the lower lid and on the eyelashes of the upper lid.
g) Close the eye and wash away the soapy solution from the eyelids with clean warm water.
h) Dry the eyelids with a tissue before opening them.
i) Instil a drop of artificial tears.
j) Only if prescribed: Gently spread a small amount of cream or ointment on the eyelid margins (this may sting for a
short while).
K) Repeat for the other eye.
Frequency: 2/day for 1-3 months Once you have been diagnosed as having blepharitis, it means that you are predisposed to this
problem, and you should see your optometrist or ophthalmologist at least yearly to check whether another course of cleaning is necessary.

2. ANTIBIOTICS
   (a) Only if adequate improvement is not obtained with eyelid hygiene alone should fucidic acid
   cream (Fucithalmic®) be applied to the lid margin after each cleaning. (b) An antibiotic and steroid ointment may also be tried.
   (c) Systemic tetracyclines are often helpful, especially when the condition is associated with
   seborrhoeic dermatitis or acne rosacea.
3. OTHER TREATMENTS
   (a) Warm compresses may be useful in the case of blocked tarsal glands. (b) Manual expression of thickened tarsal gland contents.
   (c) Treatment of seborrhoeic dermatitis of the head with special shampoo.
4. Follow up 1/year

Question 10

Infection and inflammation: MOLLUSCUM CONTAGIOSUM

Pathophysiology
Presentation
Treatment

Answer 10

PATHOPHYSIOLOGY
A common viral skin disease caused by a member of the pox virus family. It occurs mainly in children and is spread by direct contact.

CLINICAL FEATURES

1. A raised, shiny, pink to white nodule on the eyelid skin with characteristic central umbilication. 2. Lesions may be single or multiple.
2. In patients with AIDS the lesions are often more confluent and disseminated disease may be present.
3. Eyelid margin lesions may result in a toxic secondary keratoconjunctivitis.
4. The lesions usually resolve spontaneously in 3-12 months.

TREA TMENT

1. reduce transmission or to prevent corneal complications.
2. Incision and curettage is the treatment of choice.

Question 11

Positional defects: ENTROPION

Definition
Causes
Treatment

Answer 11

Definition: Inversion of the eyelid margin–> retroverted eyelashes usually scratch the cornea, causing epithelial damage and irritation.

Causes: involutional changes of ageing and scarring.

Treatment: surgical.

Question 12

Positional defects: ECTROPION

Definition
Causes
Treatment

Answer 12

Definition: Eversion of the eyelid margin –> lower lid no longer guides tear flow to the inferior punctum–> epiphora.

Causes: involutional changes of ageing and scarring.

Treatment: surgical.

Question 13

Positional defects: PTOSIS

Definition
Causes
Treatment

Answer 13

Definition:
Ptosis is an abnormal drooping of the upper lid.
Normally the upper lid covers only the superior 1-2 mm of the cornea.

ÆTIOLOGICAL CLASSIFICATION
1 NEUROGENIC
(a) Oculomotor (III) paralysis
(b) Horner’s syndrome: sympathetic denervation.
2 INVOLUTIONAL
Involutional changes of ageing result in stretching of the levator aponeurosis or dehiscence of the aponeurosis from the tarsal plate.
3 MECHANICAL
Increased mass or volume in the upper lid due to factors such as oedema or tumours.
4 MYOGENIC
Abnormalities of the levator muscle itself and its neuromuscular junction:
(a) Congenital dystrophy
(b) Myasthenia gravis: characteristically the ptosis is absent or minimal on waking in the morning and worsens as the day wears on.

TREATMENT
Referral is urgent in the following circumstances:
(a) Children under 8 years: danger of amblyopia if the pupil is covered by the upper lid.
(b) Recent onset: especially if due to oculomotor (III) paralysis.

Question 14

Anatomical Deformities: DERMATOCHALASIS

Definition
Treatment

Answer 14

Definition: There is excessive loose skin on the upper lid as a result of involutional changes of ageing.

Treatment: When this begins to interfere with opening the eyes, surgical removal of the excess skin is indicated.

Question 15

Anatomical Deformities: EPICANTHUS

Definition
Treatment

Answer 15

Definition: An epicanthic fold is a congenital vertical skin fold between the upper and lower lids, covering the medial canthal angle. Its significance is that it may mimic esotropia (pseudostrabismus).

Treatment: In Europeans it usually disappears as the child’s facial bones grow, but it is common in Oriental adults.

Question 16

Tumors:

Answer 16

XANTHELASMA
Presents:
- Flat/raised
- yellowish lipid deposits under the skin
- medial canthus. 
Cause: Hyperlipidemia.

NEOPLASMS
1. BASAL CELL CARCINOMA
- Commonest primary malignant tumour of the eyelids
- Peak incidence in the elderly.
2. SQUAMOUS CARCINOMA
- Second most common primary malignant tumour of the eyelids, but nevertheless relatively rare.
- Commoner in young patients with AIDS.
3. TARSAL GLAND (MEIBOMIAN) CARCINOMA
Consider in chalazion recurs several times.
4. KAPOSI’S SARCOMA
Presents: A red, elevated tumour of the conjunctiva and eyelids in patients with AIDS.

Question 17

Eyelid opening

Answer 17

1. Levator palpebrae superioris lifts the upper lid: oculomotor nerve (III).
2. Superior tarsal muscle of Müller also plays a rôle in lifting the upper lid: sympathetic system.