EYELIDS: REVIEW OF CLINICAL

ANATOMY AND PHYSIOLOGY05.09.2014

Ayesha S. Abdullah

Learning outcomes

Correlate the structure of the eyelids with their functions

Identify the anatomical landmarks and histological

structures on photographs and microphotographs of the

eyelids.

Important superficial anatomical

landmarks

Lid margin

Upper lid creasePalpebral fissure height

(max)

Palpebral fissure length (max)

Anatomy

Mobile tissue curtains placed in front of the eyeballs

1. Cutaneous layer

Delicate, elastic with fine downy hair

Loose areolar layer beneath it

Gross oedema

2. Muscular layer

i. Orbicularis oculi

ii. Levator palpabrae superioris

iii. Muller’s muscle

3. Fibrous layer

i. Septum orbitale

ii. Tarsal plate with meibomian glands.

4. Mucous membrane Conjunctiva

CMFM

The eyelid margin

Glands of the eyelids

1. Mebomian glands:

Modified sebaceous glands,

30-40 in upper lid, 20-30 in lower lid.

2. Glands of Zeis:

Sebaceous glands along the hair follicles of lashes

3. Glands of Moll:

Modified sweat glands, lies between the lashes, opens

directly on lid margin or into the glands of Zeis.

Blood Supply

Lacrimal and palpebral branches of ophthalmic

Facial artery

Superficial temporal artery

Infraorbital artery

Upper lid has two arterial arcades

Lower lid has one arterial arcade

Nerve Supply

Supratrochlear, supraorbital and lacrimal are branches

of ophthalmic division of V. nerve.

Infraorbital, a branch of the maxillary division of V.

nerve

Venous & Lymphatic Drainage

Ophthalmic Vein

Temporal vein

Facial vein

Outer portion drains to preauricular L.nodes.

Inner portion to submandibular nodes.

Physiology

Protective

Reflex blinking—protects from air-born particles and intense light.

Optical—spreads tear, oily layer

Supportive– stabilizes globe

Lacrimal- pump mechanism in drainage of tears down the canaliculi

Cosmetic

Facial Expressions

Opening movements

LPS muscle – primary elevator

Fronatalis muscle – Accessory elevator

Muller’s muscle

Lower lid retractors

Closing movements

Orbicularis muscle – 3 diff functional units

Spontaneous blinking & tactile corneal reflex Pretarsal

Voluntary blinking and sustained activity - Preseptal and Pretarsal

Forceful closure – pretarsal, preseptal and orbitral fibres

Congenital anomalies

Coloboma

Epicanthus

Distichiasis

Blephrophimosis syndrome

Anchyloblephron

Congenital ectropion

Telecanthus

Anomalies of Eyelashes

Trichiasis

Congenital or acquired

Trachoma, chronic blephritis, membranous

conjunctivitis

Madarosis (Scanty eyelashes)

chronic blepharitis, skin disorders and leprosy

Poliosis (Whitening of eyelashes)

chronic blepharitis and trachoma

HW

What is the significance of Gray Line at the lid margin?

One line answer

Due date: Friday 12th Sep

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