Entropion is a malposition resulting in inversion of the eyelid margin. The morbidity of entropion is a result of ocular surface irritation and damage. Successful management of entropion depends on appropriate classification and a procedural choice that adequately addresses the underlying abnormality.
 View Image | Involutional entropion. Note overriding orbicularis oculi muscle, eyelid margin entropion, and relative enophthalmos with deep superior sulcus. |
The pathophysiology of entropion depends on the type of entropion seen and is discussed below.
The primary morbidity is ocular surface irritation. Corneal abrasions and scars can occur.
Entropion has no sexual predilection.
Although all ages can be affected, entropion is seen primarily in older adults.
The first order of business when assessing the patient with entropion is to determine the etiology and place it into an appropriate classification.
Dysgenesis of the lower eyelid retractors may be present creating instability in the eyelid with consequent entropion, or a paucity of tissue may be present vertically in the posterior lamella of the eyelid. Structural defects in the tarsal plate also may result in a tarsal kink syndrome, with entropion in the upper eyelid.[1]
Spastic closure of the eyelids allows the orbicularis oculi muscle to overwhelm the oppositional action of the lower eyelid retractors, resulting in an inturning of the eyelid margin and further irritation of the ocular surface from the inturned eyelashes. Most of these patients often have an involutional component as well.
The patient may exhibit horizontal laxity of the medial and/or lateral canthal tendons.
The snap test is a useful diagnostic maneuver. The eyelid margin is pulled away from the globe, with poor resultant snap back to the globe surface. Make sure the patient does not blink the lid back. If entropion is suspected but not elicited when the patient is in an upright position, lay the patient in a supine position and have him or her squeeze the eyelids closed. This will often manifest the entropion by allowing the orbital soft tissues to settle posteriorly, allowing the eyelid to turn inward. Patients usually have an involution of the posterior eyelid retractors, with the eyelid inturning in much the same manner as with spastic entropion. Involution of the soft tissues of the orbit, particularly the orbital fat, may lead to involutional enophthalmos, which in turn can lead to unstable eyelid position with entropion.
These patients usually will display scar tissue of the conjunctiva, usually a result of trauma, chemical burns, Stevens-Johnson syndrome, ocular cicatricial pemphigoid (OCP), infections, or local response to topical medication. Digital eversion of the eyelid margin is difficult in cases of cicatricial entropion, whereas it is quite easy in cases of involutional entropion. Examination of the tarsus and palpebral conjunctiva usually will point to the diagnosis in these cases. See the image below.
View Image | Left lower eyelid cicatricial entropion with lower eyelid retraction. |
Entropion can be divided into the following classes: congenital, acute spastic, involutional, and cicatricial.
View Image | Involutional entropion. Note overriding orbicularis oculi muscle, eyelid margin entropion, and relative enophthalmos with deep superior sulcus. |
View Image | Cicatricial entropion of upper eyelid. Note eyelid margin inversion. |
View Image | Cicatricial entropion of the upper eyelid with eyelid everted. Note scar tissue involving tarsal conjunctiva. |
The congenital form of entropion is very rare. It may arise due to a number of underlying developmental abnormalities, usually in the lower eyelid. Facial nerve paralysis in the pediatric population has been shown to be associated with lower lid entropion.[2]
Acute spastic entropion usually occurs as a result of ocular irritation, which may be due to infectious, inflammatory, or traumatic (eg, surgical) processes.
Involutional entropion usually is due to a constellation of problems.
Cicatricial entropion occurs as a result of scarification of the palpebral conjunctiva, with consequent inward rotation of the eyelid margin.
Entropion must be distinguished from a number of other conditions that may simulate entropion.
Epiblepharon is a congenital condition in which the pretarsal orbicularis muscle and the skin covering the eyelid override the eyelid margin and push the eyelashes vertically or inwards. The eyelid margin in these cases actually is in a normal position. This condition most commonly is seen in the lower eyelids and is more common in Asians. Compared to congenital entropion, epiblepharon usually resolves spontaneously as the face matures.
Eyelid retraction also may simulate entropion in both the upper and lower eyelids. However, the eyelid margins in these cases display a normal apposition to the globe.
Trichiasis and distichiasis are conditions in which misdirected eyelashes are directed toward the globe. While trichiasis may coexist with entropion, particularly in cicatricial cases, it is a distinct entity and requires its own treatment approach.
Very few laboratory ancillary studies are required in the workup of entropion.
For patients with a cicatricial entropion picture in whom ocular cicatricial pemphigoid is suspected, an autoimmune process should be ruled out by testing for antibasement membrane antibodies on a section of conjunctiva obtained during a biopsy.
For patients with involutional entropion it is helpful to document exophthalmometry readings to determine if relative enophthalmos is present.
It is wise to examine the mouth of patients with cicatricial entropion, for the purpose of detecting oral mucus membrane lesions and also to verify the presence of adequate mucus membrane or hard palate if grafting procedures are required.
Medical therapy may be warranted for patients with entropion who decline surgery and as a temporizing maneuver in patients who may improve spontaneously.[3]
Ocular lubrication and tear preparations are helpful for protecting the ocular surface and also may break the cycle in patients with spastic entropion due to dry eye syndrome.
Eyelid hygiene, antibiotics, and corticosteroids are useful for the treatment of blepharitis, which may cause spastic entropion.
Small amounts of botulinum toxin (BOTOX®) (approximately 5 U) are quite effective for the treatment of spastic entropion by weakening the pretarsal orbicularis oculi muscle.
Patients with cicatricial entropion secondary to ocular cicatricial pemphigoid may benefit from systemic chemotherapy, usually dapsone.
Multiple surgical procedures have been described for the management of entropion.[4, 5, 6, 7] The procedure chosen must be appropriate for the class of entropion being treated.
View Image | Involutional entropion. Correction of entropion with eyelid retractor reattachment and lateral canthopexy. |
The most common procedures utilized in the management are discussed below.[7]
They are effective for many cases of spastic entropion, as well as for some cases of involutional entropion in which the patient refuses or is medically unable to undergo more definitive procedures.
Full-thickness eyelid sutures (usually gut suture) from the inferior fornix anteriorly toward the lashes are used to torque the eyelid margin away from the globe. Tissue reaction to the gut suture helps to create a cicatrix in the eyelid that maintains the eyelid in the everted position.
It may require repair of the horizontal laxity via medial and/or lateral canthal tightening.
The vertical component is best repaired by vertically shortening or reattaching the lower eyelid retractors to the inferior border of the tarsus via a lower eyelid transcutaneous approach.
A small amount of the pretarsal orbicularis oculi can be resected concurrently to prevent further overriding of the tarsus.
They will depend on the degree of scarring and entropion, the etiology of the cicatricial changes, and the status of the tarsal plate.[8, 9]
Mild cases can be treated with a transverse blepharotomy with marginal rotation (Wies procedure).
More extensive scarring may require oral mucous membrane (eg, buccal mucosa) or cadaveric dermis (eg, Alloderm) grafts.
It is important that the inflammatory process is in a quiescent state in OCP patients prior to any procedure that violates the conjunctiva. Any manipulation of the conjunctiva in these patients may cause a recurrence of inflammation with failure of the procedure.
Assess the status of the tarsal plate in all cases of cicatricial entropion. If it is distorted, place a facsimile of tarsus following excision of the distorted portions of the tarsal plate. Materials such as autologous tarsus, hard palate grafts, and chondromucosal grafts have been used successfully for this purpose.
Consultation with an internist or a hematologist is recommended for OCP patients requiring immunosuppressive medications, as well as for systemic evaluation to rule out other autoimmune diseases.
Any surgical procedure can have immediate or delayed complications.
Immediate complications include hemorrhage, infection, wound dehiscence, graft failure (donor and recipient sites), corneal injury, and recurrence of the entropion, as well as consecutive ectropion.
Hemorrhage is treated with cauterization of the bleeding points, and infection is managed with antibiotics directed at culture-specific organisms.
Wound dehiscence may require immediate surgical repair if extensive or conservative management if mild.
Maintain grafts by stenting the grafted site for the purpose of graft immobilization.
Graft failure may require debridement with delayed re-operation.
Donor site complications, particularly bleeding, are managed with appropriate packing material.
Consecutive ectropion may occur and may respond to conservative observation during the healing period with late secondary repair.
Topical, local, and systemic medications may be useful in the management of various forms of entropion.
Clinical Context: Preservative-free artificial tears are preferred to avoid preservative-associated ocular reactions.
Topical ocular lubricants may be necessary to increase patient comfort and to diminish abrasive conjunctivopathy and keratopathy.
Clinical Context: Bactericidal and bacteriostatic against mycobacteria; mechanism of action is similar to that of sulfonamides where competitive antagonists of PABA prevent formation of folic acid, inhibiting bacterial growth.
These medications have been shown to effectively diminish the autoinflammatory reaction associated with ocular cicatricial pemphigoid.
Clinical Context: Temporarily paralyzes the muscles by inhibiting acetylcholine release. Duration of effectiveness usually is 3-4 mo.
Weakening or paralyzing the orbicularis muscle of the lower eyelid helps in preventing the inturning of the lower eyelid in cases of spastic and involutional entropion.
Involutional entropion. Note overriding orbicularis oculi muscle, eyelid margin entropion, and relative enophthalmos with deep superior sulcus.
Left lower eyelid cicatricial entropion with lower eyelid retraction.
Involutional entropion. Note overriding orbicularis oculi muscle, eyelid margin entropion, and relative enophthalmos with deep superior sulcus.
Cicatricial entropion of upper eyelid. Note eyelid margin inversion.
Cicatricial entropion of the upper eyelid with eyelid everted. Note scar tissue involving tarsal conjunctiva.
Involutional entropion. Correction of entropion with eyelid retractor reattachment and lateral canthopexy.
Involutional entropion. Note overriding orbicularis oculi muscle, eyelid margin entropion, and relative enophthalmos with deep superior sulcus.
Involutional entropion. Correction of entropion with eyelid retractor reattachment and lateral canthopexy.
Cicatricial entropion of upper eyelid. Note eyelid margin inversion.
Cicatricial entropion of the upper eyelid with eyelid everted. Note scar tissue involving tarsal conjunctiva.
Left lower eyelid cicatricial entropion with lower eyelid retraction.
Left lower eyelid posterior lamellar cicatrix
Repair of left lower eyelid cicatricial entropion and retraction with cicatrix release and hard-palate mucosal graft.
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