Acute spastic entropion is the result of eyelid swelling along with orbicularis spasm that results in a temporary in-turning of the eyelid. A cycle of corneal irritation from the entropion, causing more eyelid spasm and more irritation, must be broken, so the eyelid can return to normal. Many of these patients will have underlying involutional changes (laxity) that may result in a recurrent entropion.

Eyelid laxity, both horizontally and vertically, predisposes to the instability of the lower eyelid. The additional factor required is the ability of the patient’s orbicularis muscle to override the tarsus and drive the eyelid inward. Patients present with red, irritated eyes from the eyelid margin, and the eyelashes come into contact with the eye itself.

Cicatricial entropion is caused by conjunctival scarring pulling the eyelid inward. Generally, treatment is surgical, but defining and treating the cause of the conjunctival scarring must be done first; otherwise most cases will recur. Cicatricial entropion can occur in the upper or lower eyelid.

Involutional ectropion has the same involutional factors as in an involutional entropion (e.g., horizontal laxity, vertical instability). These patients do not have hypertrophic, spastic orbicularis muscle to override, so the unstable eyelid sags outward instead of being driven inward. Symptoms are less acute and not as severe as in involutional entropion. Many patients will have mild involutional ectropions and may be asymptomatic.

Paralytic ectropion is the result of temporary or permanent seventh cranial nerve palsy. The lower eyelid sags away from the globe, resulting in loss of protection of the eye and inability of the lacrimal system to collect tears. Patients with less severe palsy and other eye protective mechanisms intact present with tearing. Patients with more severe palsies and poor eye protection mechanisms present with corneal breakdown.

Cicatricial ectropion is caused by mechanical shortening of the anterior lamellae of the eyelid pulling the eyelid down and outward. This results in tearing and corneal exposure. More common in the lower eyelid but can occur in the upper eyelid.

Mechanical ectropion is a rare cause of ectropion in which a mass of some type pushes the eyelid outward. There are usually associated involutional changes that allow the eyelid to be pushed outward.

• Age: Any age

• Gender: More frequent in women

• Etiology: The following can result in scarring of two conjunctival surfaces:

• There may be no history, just asymptomatic symblepharon noted on examination.

• Patients with history of eye or eyelid trauma or inflammation may also have symblepharon.

• The differential diagnosis involves determining the cause of the symblepharon, not whether the process is a symblepharon.

• Conjunctival scarring of unknown etiology requires a conjunctival biopsy with immunofluorescence testing to rule out ocular cicatricial pemphigoid.

• In rare cases, squamous cell carcinoma may cause symblepharon; therefore, pathologic evaluation should be considered in select cases.

• Variable depending on the cause of the symblepharon

• Age: Any age. Nontraumatic causes are rare in childhood. More common with increasing age

• Gender: More common in females

• Etiology: Lash follicles are distorted and become misdirected with scarring of the eyelid. Chronic eyelid inflammation may result in growth of misdirected lashes. Chronic blepharitis, eyelid trauma, and conjunctival scarring diseases can all cause trichiasis.

• Patients will often have a history of chronic eye irritation and inflammation. They may also have a long history of eyelash problems. There may be a history of eyelid trauma or surgery.