Ectropion is a condition characterized by outward turning of the eyelids (usually the lower lid). It is usually found in the elderly, where the muscles surrounding the eye become weak with ageing. It can be congenital, and can also be found in patients with facial palsy or scarring of the eyelid. Ectropion prevents the eyelid from closing properly and protecting the cornea (transparent front part of the eye). This can damage the cornea and affect normal vision.
Ectropion (out-turning of the eyelid) is classified into the following categories on the basis of etiology:
- Congenital ectropion -This is due to a developmental vertical foreshortening of anterior lamellar tissue, resulting in eversion of the lid margin
- Cicatricialectropion -This results from vertical foreshortening caused by acquired scarring or inflammation and may coexist with involutional horizontal lengthening of the lid margin due to chronic vertical traction; treatment in these cases is directed at lengthening the lid vertically with midface lifting or skin grafts or flaps; concomitant repair of any horizontal component is similar to repair of involutionalectropion
- Mechanical ectropion -This is due to a mass effect on the eyelid (eg, from a tumor), which pulls the lid margin away from the globe; it is managed through treatment of the underlying causative factor (eg, tumor excision)
- Involutionalectropion -This is due to horizontal laxity of the eyelid, leading to stretching of the lid or dehiscence of its attachments at the medial or lateral canthus, with resultant out-turning of the lid margin