eye lids

• Anatomy of the eyelids:

  • Eyelids are movable folds attached to the margin of the orbital opening
  • Covered anteriorly by skin and posteriorly by the conjunctiva
• Structures of the eyelid:

  • Skin
  • Subcutaneous fascial layer
  • Muscle layer: 3:orbicularis oculi, levator palpebrae superioris, and Muller muscles
  • Submuscular areolar tissue
  • Tarsal plate: thin plate of fibrous tissue with the meibomian gland embedded in it
  • Palpebral conjunctiva
• The lid margin:

  • Free edge of the eyelid carrying the eyelashes
• Blood supply:

  • Ophthalmic and lacrimal arteries
  • Veins follow the corresponding arteries
• Congenital anomalies of the lids:

  • Epicanthus: semilunar fold of skin at the side of the nose
  • Ankyloblepharon: lid margins fused congenitally
  • Coloboma of the lid: lack of a part of the lid due to arrested development
  • Blepharophemosis: congenitally narrow palpebral fissure
  • Distichiasis: extra row of lashes
  • Ptosis: drooping of the upper eyelid below its normal position
• Inflammation of the lid margin (Blepharitis):

  • Chronic inflammation of the lid margin usually by staphylococci
  • Forms include squamous, ulcerative, angular, and parasitic blepharitis
  • Symptoms include itching, soreness, and lacrimation
  • Treatment involves general health attention, local antibiotics, and steroids in chronic cases
• Inflammation of the glands of the lids:

  • Hordeolum externum (stye): acute suppurative inflammation of the Zeis gland
  • Hordeolum internum: acute suppurative inflammation of the meibomian gland
  • Chalazion: chronic granulomatous inflammation of the meibomian gland
  • Treatment includes hot compresses, epilation, and local antibiotics
• Entropion:

  • Lid margin and tarsal plate turned inward
  • Types include spastic, senile mechanical, and cicatricial
  • Treatment is surgical
• Trichiasis:

  • Lashes mal-directed to the cornea and bulbar conjunctiva
  • Causes include congenital trichiasis, trachoma, and ulcerative blepharitis
  • Symptoms include foreign body sensation, photophobia, and lacrimation
  • Complications include chronic conjunctivitis and corneal ulceration
  • Treatment is surgery
• Ectropion:

  • Out-turning of the lid margin resulting in the exposure of part of the palpebral conjunctiva
  • Types include spastic, senile, paralytic, and cicatricial
  • Treatment is by surgery
• Madrosis:

  • Loss of eyelashes
  • Causes include lid coloboma, trauma, ulcerative blepharitis, and thyroid or pituitary dysfunction
• Blepharospasm:

  • Reflex involuntary contraction of the eyelids
  • Causes include corneal foreign body, severe anterior uveitis, and hysteria
• Symblepharon:

  • Cicatricial adhesion between the palpebral conjunctiva and the eyeball
• Molluscum Contagiosum:

  • Small white umbilicated swelling caused by a virus
  • Contains cheesy material when exposed