Diseases of the Eyelids

By Riad Ma'luf, MD
Assistant Professor
Department of Ophthalmology, Oculoplastics Division
American University of Beirut Medical Center
Email: rmaluf@cyberia.net.lb

                     The eyelids protect the eye by preventing contact with foreign materials and by preventing 
                     excessive drying of the cornea and conjunctiva.  

A.    Eyelid Anatomy: (fig. 1)  The eyelids are lamellar structures covered on their outer surface by thin skin and on their inner surface by conjunctiva. Between the skin and conjunctiva are the tarsal plates, the orbital septum, the upper lid elevators (Levator & Muller’s muscle) , the lower lid retractors, and the orbicularis muscle.The levator muscle is the major elevator and originates from the orbital apex just above the annulus of zinn to insert over the anterior tarsal border. It is innervated by the upper division of the third cranial nerve. Fibers from the levator aponeurosis to the skin form the lid crease. Muller’s muscle originates from the undersurface of the levator muscle and inserts on the upper tarsal border. It is innervated by the sympathetic nervous system. Interruption of these sympathetic fibers results in Horner’s syndrome (ptosis, miosis, anhidrosis). The orbicularis muscle is innervated by the seventh cranial nerve and is divided into three subdivisions: preorbital (forceful closure of the eyelids), preseptal, and pretarsal (fine blinking).

B.     Ptosis: Malposition of the upper eyelid in which the lid margin is abnormally low. Ptosis can be congenital or acquired. The type of ptosis should be carefully established by history, since the treatment of congenital ptosis is usually different from that of acquired ptosis. Ptosis must be distinguished from pseudoptosis, a condition in which the upper eyelid appears to be low without true insufficiency of the lid retractors.

1.      Congenital ptosis : (fig. 2)can be bilateral but more commonly unilateral. Associated abnormalities include:

a: Blepharophimosis-epicanthus inversus-ptosis syndrome (fig.3 )

b; Marcus Gunn “jaw winking” syndrome. Synkinesis in which the ptotic eyelid elevates with movement of mandible.( fig. 4 )

c: Extraocular muscle palsies. Mainly the superior rectus muscle.

Treatment : Usually not before three or four years of age. Levator resection should be done in cases with acceptable levator function. Otherwise a frontalis sling is required.

2.       Acquired ptosis: Levator function is usually good. May be categorized as follows:

a: Involutional (senile) ptosis. (fig. 5) Most common form of acquired ptosis. Usually is bilateral and involves elderly patients. It results from disinsertion of the levator aponeurosis.

b: Myogenic ptosis. Associated with Myasthenia gravis, muscular dystrophy, and progressive external ophthalmoplegia.

c: Neurogenic ptosis. Deficient innervation 3^rd CN to levator muscle or deficient sympathetic innervation to Muller’s muscle (Horner’s synd.)

d: Traumatic ptosis. Direct trauma to levator muscle or aponeurosis

e: Mechanical ptosis. Can be associated with lid tumors. (eg. Neurofibromatosis fig. 6 ). Contact lens induced ptosis can be disinsertional or mechanical (cobblestone papillae), and can improve upon discontinuation of the lens ( fig. 7.)

Treatment:  Involves correcting the cause when possible. If not possible, then a levator resection is to be done (in cases of acceptable levator function). In cases of poor levator function, frontalis suspension is advised.

3.      Pseudoptosis: Abnormally low upper lid with no insufficiency of the retractors.

a: Excessive upper lid skin- Dermatochalasis (fig. 8)

b: Contralateral lid retraction.

c: Enophthalmos or contralateral exophthalmos

d: Hypotropia (fig. 9)

         C.   Ectropion:  Lid margin is turned away from the globe. Lower lid is more commonly 
                   involved. Tearing may result from eversion of punctum. The congenital form is rare. 
                   The acquired form is categorized as follows:

            1. Involutional ectropion is a frequent cause of tearing (epiphora) (Fig. 10 ) .                     

               a.  Is caused by attenuation of canthal tendons and lower lid retractors.
               b. Treatment involves lid tightening procedures.                                                                                       

            2 . Paralytic ectropion  , mainly from seventh nerve injury.

                        3 .  Mechanical ectropion

4.      Cicatricial ectropion  caused by scarring and secondary skin traction (Fig. 11 and  Fig. 12)

D.   Entropion: Lid margin is turned toward the globe. Inturned lid margin may damage the    
       cornea and cause keratitis or ulceration. The acquired form is categorized as follows:

                       1. Involutional entropion usually involves the lower lid. (Fig. 13). Also caused by  
                           attenuation of lid  structures(retractors & canthal tendons).  

                       2. Cicatricial entropion  is usually the result of tarsoconjunctival shrinkage. May be 
                           caused by trachoma, Stevens -Johnson syndrome, ocular pemphigoid, or burns.

E.    Eyelash disorders:

                      1.  Distichiasis : extra row of lashes arise from the lid margin, frequently from meibomian 
                           gland orifices.

                      2.  Trichiasis: Lashes are directed posteriorly toward the surface of  the eye.

                      3.  Madarosis:  Loss of lashes

                  F.   Eyelid tumors: (malignant)

1. Basal cell carcinomas; (fig. 14)

               -Most common malignant tumors of the eyelids

               -Most frequently arise on sun exposed lower lids

                                            -More commonly nodular with pearly surface

                                            -Invade adjacent areas, however rarely metastasize to distant areas

2.  Squamous cell carcinomas:

      -Less common than basal cell carcinomas
      -Potential of metastasis                                                

                             3.     Malignant melanomas:  
                                    
                             -Uncommon
                             -Metastasis is common
                                    - May evolve from preexisting nevi

                             4.    Sebaceous cell carcinomas :    (fig. 15)              

                                    -   Arise from meibomian glands
                                    -   Highly malignant
                                    -   Growth may mimic chalazion  ( caution in cases of recurrent chalazia)

G. Eyelid inflammation & degeneration: 

1.  Blepharitis :

-   Very common condition

-   Associated with conjunctivitis

-   May be associated with Staphylococcus infection

-   Treatment:    
              a. Mechanical debridement of lid margin (using cotton  
                  applicators)

              b. Topical antibiotics

                    c. Warm compresses

2.  Chalazion: ( Fig. 16)

-   focal  inflammation of a meibomian gland

-   Treatment:  
               a. Warm compresses

                     b. Incision & curettage may be necessary in some cases

3.  Blepharochalasis:

                                              - Results from repeated idiopathic episodes of eyelid 
                                                 edema and inflammation---à wrinkling of skin & ptosis

                                              -More common in young females

                                              -Treatment:  Blepharoplasty

4.  Dermatochalasis: (fig. 8)

-   Redundancy of the skin of the eyelids

-   Involutional change among old people

-   Familial predisposition is common

-   Treatment:   Blepharoplasty