The Eyelids pdf - D. Mutaz

Ophthalmology

Dr. Muataz Hasan

THE EYELIDS

Eyelids are thin movable curtains composed of skin on their anterior
surface and mucus membrane (conjunctiva) on the posterior surface, they
contain:

1- Smooth muscles (Müller's muscles).

2- Striated muscles (Orbicularis oculi and Levator palpebrae superioris
"LPS").

3- Dense fibrous plates (Tarsal plates).

4- Glands.

5- Nerves and blood vessels.

The eyelids protect the eye from injury and excessive light. And prevent
excessive dryness of the cornea and conjunctiva.

Macroscopic anatomy:

The eyelids are two movable mucocutaneous folds, which act as shutters.
The upper lid extends above to the eyebrow while the lower lid passes
without a line of demarcation into the skin of the cheek.

The palpebral fissure is the space enclosed between the two lid margins
when the lids are open.

In adults the palpebral fissure is 30 mm in length and 15 mm in width.

Microscopic Anatomy:

The eyelid is formed of 6 layers:

1. Skin: very thin skin loosely attached to the underlying structures.
2. Subcutaneous areolar layer: loose connective tissue containing no fat.

3. Muscular layer: containing the levator palpebrae superioris, and

Muller's muscle.

4. Submuscular layer: loose connective tissue containing the main blood

vessels and nerves of the lid.

5. Tarsus: the tarsal plate is a condensed fibrous tissue resembling

cartilage it acts as the skeleton of the lid.

6. Palpebral conjunctiva: The conjunctive is very thin, vascular, and

firmly adherent to the tarsus by fibrous bands.

THE MUSCLES OF THE LID:

1-Orbicularis oculi muscle: the orbicularis muscle is the sphincter of the
lid and has 3 portions.

1. Palpebral portion:



it is the central part of the muscle and may be divided into pre-

septal and pre-tarsal parts.



Action: simple closure of the lids as in blinking. It supports the

lower lid in its place.

2. Orbital portion:



Action: tight closure of the lids.

3. Horner's muscle (pars lacrimalis):



Thin layer of muscle fibers arising from the posterior lacrimal

crest and lacrimal fascia, when this muscle contracts it opens the
lacrimal sac

 Nerve supply:

o The orbicularis muscle is supplied by the 7th cranial nerve

(facial).

2-Levator palpebrae superioris muscle:



Origin: the levator muscle arises from the lesser wing of the

sphenoid bone at the apex of the orbit.



Insertion: the muscle has several insertions

o  Skin of the upper lid at the upper palpebral sulcus.
o  Upper tarsus.
o  Upper fornix of conjunctiva.



Nerve supply: 3rd cranial (oculomotor) nerve via its superior

division



Action: elevation of upper lid.

Paralysis of the levator muscle leads to ptosis

3- Superior palpebral muscle (Müller's muscle or superior tarsal
muscle):



It is a small sheet of smooth muscle originated from the under

surface of the LPS muscle and inserted to the upper edge of the
upper tarsal plate.



Nerve supply: Sympathetic nerves.



Function: Like LPS, is to keep the palpebral fissure open against

gravity.

GLANDS IN THE EYELIDS:

1. Meibomian glands (Tarsal glands):



Modified sebaceous gland located in the tarsal plate. The upper

tarsus contains 30-40 glands, while the lower tarsus contains 20-30
glands.



Function: It forms the outer lipid layer of the tear film.

2. Zeis glands:



Modified sebaceous gland opened with lash follicles.

3. Glands of Moll:



They are modified sweat gland whose ducts also open into lash

follicle or directly in the anterior lid margin between the lashes.

CONGENITAL ANOMALIES OF THE LIDS

1. Epicanthus:



Definition: Semi- lunar fold of skin at the side of the nose.



Etiology:

o  Congenital.
o  Racial (Mongolians)
o  Familial.



Clinical picture:

 Usually bilateral.
 Semilunar fold of skin is seen covering the caruncle.

2. Lid Coloboma : notching of the lid margin ( full thickness

developmental defect)

3. Congenital Malpostion:

 Ptosis
 Entropion
 Ectropion.

4. Distichiasis: extra row of lashes.

5. Ankyloblepharon: Imperfect separation of the eyelids



Treatment: Open the adhesion in between.

Blepharophimosis: Narrowing of the palpebral fissure.



Treatment: Plastic surgery at pre-school age.

BLEPHARITIS

Belpharitis usually presents as a chronic blepharo-conjunctivitis and it is
the most common external eye disorder in clinical practice.

Types:

Squamous Blepharitis:

It is low grade infection on top of abnormal secretions of the lid similar to
seborrheic dermatitis.

Clinical picture:



Small, white, scales are present between the lashes.



Removal of the scales reveals a hyperemic lid margin without

ulceration.

Treatment:

 General treatment of seborrhea.

 Remove scales with 3% sodium bicarbonate or diluted baby

shampoo.

 Rub antibiotic ointment into the lid margin.

 The treatment must be prolonged 2 – 3 weeks.

Ulcerative Blepharitis:

Etiology:

Infection

the

lid

margin

with

staphylococcus

aureus

(sebaceous, sweat gland and hair follicles)

Signs:



Yellow crusts glue the lashes together.



Minute ulcers of the lid margin which bleed easily when crusts are

removed.

Treatment:

 Lid hygiene

o Frequent massage to evacuate meibomian secretions

o Meticulous removal of scales by scrubbing the lid margins

with baby shampoo or 3% sodium bicarbonate lotion.

 Elimination of infection

INFLAMMATION OF THE GLANDS OF THE LID

1. Stye (Hordeolum externum):



Acute suppurative inflammation of Zeis gland and the lash follicle,

forming a small abscess.

Etiology:

 Infection of a Zeis gland by staphylococcus aureus

 Predisposing factors: diabetes, poor general resistance, errors of

refraction and ulcerative blepharitis.

Clinical picture:

Symptoms:



Swelling of the lid



Severe pain, first dull then throbbing.

Signs:

Diffuse red swelling

 Related to a lash

 Close to the lid margin.

 Points on the skin side.

Treatment:



Hot fomentations.



Local antibiotic drops and ointment.



Systemic antibiotics.



When pointing occurs. The pus must be evacuated by :

o Epilation of the related lash

o Horizontal incision

For recurrent cases: correct the underlying cause

2. Hordeolum internum

Acute suppurative inflammation of the meibomian gland caued by
staphylococcus aureus. It may be primary or it may occur on top of a

chronic inflammation of the mebomian gland (chalazion) Hordeolum
internum should be differentiated from hordeolum externum(stye).

Chalazion (cyst)

It is a chronic non – specific inflammatory granuloma of mebomian
gland.

Etiology:



Etiology unknown.



It is a granuloma produced by the retained contents of the gland

following obstruction of its duct, or as a result of chronic irritation
by a low virulence organism.

Clinical Picture:

Symptoms:



Painless swelling of a long duration felt under the lids.



Pain occurs only when it become infected

Signs:

 Slowly growing painless swelling of the tarsus.
 If the lid everted, the conjunctiva is seen red over the nodule.

Treatment:

a. Very small chalazion: Vitamin A, local antibiotic and steroid

preparation.

b. Marginal chalazion : scraping from lid margin followed by

diathermy

c. Moderate or large chalazion: vertical incision and scraping through

the conjunctival side.

d. Multiple chalazia: combined excision of tarsus and conjunctiva

leaving the lower third of the tarsus (to avoid lid notching) with
replacement by a mucous graft from the lip.

e. Recurrent chalazion of the same gland: excision biopsy to exclude

malignant tumor.

DISORDERS OF EYELASHES

1. Trichiasis: Trichiasis is a condition where more than 4 lashes are

rubbing against the cornea or conjunctiva.

2. Rubbing lashes: Rubbing is a term applied to the condition when 4

lashes or less are misdirected or rub against the cornea or
conjunctiva.

3. Madarosis: permanent absence of eye lashes due to destruction of

the lash follicles.

4. Distichiasis: An extra row of lashes situated in or near to the

openings of the meibomian glands.

5. poliosis: whitening of the lashes.

MALPOSTION OF THE EYELID

Entropion

Definition:

Entropion is the rolling inwards of the eyelid. The whole row of the lashes
will be rubbing against the cornea and finally there will be a deformity of
the tarsus.

Types:

a. Cicatricial (fibrotic) entropion: Fibrosis of the palpebral

conjunctiva due to trachoma, chemical burns, diphtheria and ocular
cicatricial pemphigoid.

b. Spastic entropion: due to spasm of orbicularis muscle in response

to ocular irritation e.g inflammation, exposed sutures, operations
following enucleation or enophthalmos.

c. Involutional (senile) entropion: affects only the lower lid due to

overriding of the preseptal portion of orbicularis muscle over the
pretarsal portion.

d. Congenital entropion: usually affecting the whole lower eyelid.

Ectropion

Definition:

Ectropion is rolling outwards of the eyelid from the globe. It usually
affects the lower lid as it stands against gravity.

Types:

a. Involutional (senile) ectropion: due to senile weakness of the

orbicularis muscle and relaxation of the palpebrall ligaments.

b. Cicatricial (fibrotic) ectropion: due to scarring and contracture of

the skin of the lower lids by burns, trauma or tumor.

c. Paralytic ectropion: due to paralysis of orbicularis muscle in facial

nerve palsy.

d. Mechanical ectropion: due to increased weight of lower lid by e. g.

multiple chalazia.

e. Congenital ectropion: rare

Ptosis

Definition:

Ptosis is the drooping of the upper eyelid that normally covers the upper
1/6 of the cornea.

Etiology (types)

Myogenic ptosis: due to disorders of levator muscle.

a. Congenital ptosis: due to dystrophy of levator muscle.

b. Acquired ptosis: myasthenenia gravis: due to a defect at the

myoneural junction.

Neurogenic ptosis: due to a disorder of nerve supply.

a. Third nerve palsy: paralytic ptosis (diabetes, congenital, or

traumatic)

b. Horner's syndrome: due to disorder of sympathetic nerve supply

leading to Mullers muscle paralysis. (partial ptosis, miosis,
anhydrosis and enophthalmos)

A poneurotic ptosis: due to disorder of levator aponeurosis .

a. Involutional (senile) ptosis: degenerative process with age.

b. Postoperative ptosis: after cataract or retinal detachment surgery.

Mechanical ptosis:

a. Excess weight due to edema, trauma, tumor.

b. Conjunctival scarring.

Important clinical points:

Measurement of degree of ptosis:

a. Measure the vertical distance bet. Center of upper lid margin &

lower limbus (VFH)

 Normally: 9mm

 Mild: dropping 1-2 mm

 Moderate: dropping 3 mm

 Severe: drooping 4mm or more.

b. Margin – reflex distance (MRD):

 Measure the distance between upper lid margin & corneal light

reflex.

 Normally: 4 – 4.5 mm.

Determine the levator function:

 Correct head position & ask patient to look down to relax frontalis

ms.

 Fix eye brow against supra- orbital margin using the thumb to

prevent elevation by frontalis ms.

 Ask patient to look up.

 Measure elevation of lid margin in mm using ruler:

 Grades:

 normal

15mm

 Good

12- 15 mm

 Fair

5 - 11mm

 Poor

4 mm

Test of extra- ocular ms movement: to exclude 3

n. palsy.

Treatment:

The treatment of all types is surgical except in myasthenia gravis, where
the treatment is medical. Surgical procedures are:

a- Levator resection.

b- Frontalis brow suspension (Sling operation).

c- Tarso-conjunctival resection (Fasanella servate procedure).

• Choice of one of these three types depends on:

a- Aetiology of ptosis.

b- Severity of ptosis: Mild, moderate or severe.

c- Function of LPS: Good, fair or poor.