Entropion is a malposition in which the lower eyelid turns in. The lashes rub against the eye and cause irritation and pain. In some cases, entropion can damage the surface of the eye and result in scarring or infection.
Entropion can be caused by several issues, but is most commonly due to loose support of the lower eyelid. A combination of stretched eyelid tendons and slipped lower eyelid muscles may result in entropion (involutional entropion). In some cases, scarring of the inside of the eyelid or conjunctiva may cause entropion as well (cicatricial entropion). Prior lower eyelid surgery can sometimes cause a cicatricial entropion. In addition, spasm of the lower eyelid muscles may cause the lower eyelid to “contract” inward (spastic entropion). Rarely, a tumor or excess tissue may cause push or pull the eyelid in (mechanical entropion).
Eyelid surgery is usually necessary to repair an entropion and prevent eye damage. Entropion repair can usually be performed as an outpatient or in the office. The procedure usually causes very little pain, and at the same time relieves the pain and discomfort caused by the entropion itself. Some mild to moderate swelling and bruising is normal for the first week or two after surgery. Most patients are able to quickly resume light to moderate activity. Most sutures are dissolvable, and any non-dissolvable sutures are removed in a week.
The surgical technique used for entropion repair differs depending on the cause of the entropion. Eyelid tightening with a canthoplasty or tarsal strip is usually necessary. If the lower eyelid muscles are loose or slipped, they are repaired as well. Scarring of the conjunctiva can by releasing the scar and placing a graft (mucous membrane or synthetic). Excess tissue pushing the eyelid in can be removed if present.
Surgery is not usually necessary for spastic entropion, and boot injections can treat the problem.
Types of Entropion
Involutional Entropion (“Age related” entropion)
Involutional entropion is the most common type of entropion and is due to loosening of the supporting eyelid tissues. Often times, a combination of a stretched eyelid tendon and slipped lower eyelid muscle are the cause. Involutional entropion causes eye irritation, pain, and watering.
Eyelid surgery for involutional entropion generally consists of tightening the eyelid with a canthoplasty or lateral tarsal strip. In addition, a slipped lower eyelid muscle can be reattached from an incision on the inside of the eyelid. If any excess lower eyelid tissue is pushing the eyelid in, it can be removed as well.
Cicatricial Entropion (entropion due to scarring)
Cicatricial entropion occurs when the scarring on the inside of the eyelid causes it to rotate in. This may be due to prior surgery, trauma, burns, chemical injuries, infections, certain types of medications, and some inflammatory or autoimmune diseases.
Cicatricial entropion repair is usually necessary to get the eyelid back to its correct position. Any inflammatory or autoimmune diseases must be controlled medically prior to eyelid surgery. Cicatricial entropion repair surgery involves releasing scar tissue, and usually placing a graft in order to rotate the eyelid back into its normal position. Graft options include tissue from the mouth and synthetics. Lower eyelid tightening with a canthoplasty or tarsal strip may be necessary as well.
Mechanical entropion is a condition in which excess tissue rotates the eyelid inward. The most common type of mechanical entropion occurs is when excess skin of fatty tissue in the lower eyelid pushes the eyelids in. This often occurs in combination with involutional entropion. Surgery for this type of mechanical entropion involves removing the excess tissue from the eyelid. Mechanic entropion can also be caused by a tumor that turns the eyelid in. Treatment involves eyelid surgery that removes the tumor and reconstructs the defect (often times MOHS surgery).
Spasm of the muscle that closes the eye (the orbicularis) can cause the lower eyelid to rotate in. This condition is called spastic entropion. Is can occur due to neurologic or spastic disorders such as blepharospasm or hemifacial spasm, due to eye irritation, and sometimes occurs after eye surgery.
Spastic entropion can be treated with botulinum toxin injections (Botox). Lubricating the eye with artificial tears can help as well. Surgery is not required for spastic entropion.