Epiblepharon is a very common condition among Asian children and is a fold of the skin and underlying pretarsal orbicularis muscle that overlaps the eyelid margin and pushes the lashes against the cornea. It is manifested by the anterior lamella overriding the posterior lamella which causes the lashes to brush against the cornea. Although the prevalence of epiblepharon is known to be high among Asians, its cause remains controversial. Several etiological factors may be involved in the pathogenesis of epiblepharon.

Although epiblepharon in the lower lids lessens and disappears with age in many cases, surgery must be performed at an early age in severe cases in order to prevent ocular trauma as the vertically oriented cilia of the lashes can erode the corneal epithelium. Induced keratitis and astigmatism are indications for surgical intervention.

Over our many years of surgical experience, the investigators came to realize that the severity of epiblepharon was reduced when patients were under general anesthesia during surgery. The purpose of this study was to investigate the role of the orbicularis muscle in the pathogenesis of lower lid epiblepharon and to analyze the differences in the severity of epiblepharon in the upright versus the supine position and before and after the induction of general anesthesia.

Inclusion Criteria:

• subjects younger than 12 years
• more than 12 months' follow-up
• subjects demonstrating prominent corneal touch by cilia and/or related subjective symptoms
• subjects who underwent general anesthesia for surgical correction of epiblepharon

Exclusion Criteria:

• subjects older than 12 years
• less than 12 months' follow-up -. subjects who underwent surgery on local anesthesia

Subjects with epiblepharon which needed surgical correction