Epicanthal folds

An epicanthal fold is a fold of eyelid skin beside the nose. It partly covers the inner corner of the eye, where the upper and lower eyelids meet.

Epicanthal folds are a normal feature of human facial anatomy. They are common in babies and young children because the bridge of the nose is still developing. They are also a common inherited feature in people from several populations, particularly those with East Asian ancestry. Adults can have them too.

The folds may become less noticeable as a child’s face and nasal bridge grow. In other people, they remain visible throughout life. Neither pattern is automatically a health concern.

An epicanthal fold is not a disease or a diagnosis. On its own, it does not mean that there is a problem with the eye, vision, or development. Its main medical importance is that it can sometimes make the eyes appear crossed when they are actually aligned normally.

The inner corner of the eye is called the medial canthus. An epicanthal fold runs between the eyelid and the side of the nose, covering part of this corner.

The fold can hide some of the white part of the eye nearest the nose. This may make one eye appear to turn inward, especially when a child looks to the side or is photographed from an angle.

When the eyes only look crossed because of facial features, this is called pseudostrabismus, meaning false or apparent eye misalignment. A broad nasal bridge can add to this appearance. Light reflected from the eyes will usually remain in a matching position when the eyes are truly aligned.

Clinicians sometimes describe folds by their shape and direction. For example, epicanthus inversus is a fold that starts mainly from the lower eyelid and runs upward. These terms describe anatomy; they are not diagnoses by themselves.

Epicanthal folds do not normally cover the pupil, block light from entering the eye, or reduce vision.

Most epicanthal folds have no effect on health. No treatment or special monitoring is needed when the eyes are healthy and properly aligned.

The main issue is telling pseudostrabismus apart from strabismus, a true eye turn. In strabismus, the eyes do not point in the same direction at the same time. One eye may turn inward, outward, upward, or downward.

True strabismus in childhood can interfere with normal visual development. The brain may begin relying more on one eye, leading to amblyopia, sometimes called lazy eye. Early assessment matters because treatment is generally more effective while the visual system is developing.

Epicanthal folds may also be recorded during an examination for a genetic or developmental condition. For example, they can occur among the many physical features associated with Down syndrome. Epicanthus inversus can occur with blepharophimosis-ptosis-epicanthus inversus syndrome, a rare inherited eyelid condition.

A fold alone cannot establish any of these diagnoses. Clinicians consider the person’s overall health, growth, development, family history, examination findings, and—when appropriate—genetic testing.

The fold itself does not usually cause a problem. Concerns arise when another condition is mistaken for normal anatomy, or when a normal fold is wrongly treated as evidence of illness.

Relevant situations include:

• Pseudostrabismus: facial anatomy makes aligned eyes look crossed
• Strabismus: one eye is genuinely misaligned, constantly or at times
• Amblyopia: vision does not develop normally in one eye, sometimes because of strabismus
• Eyelid disorders: unusual eyelid shape, drooping, or narrowing affects the eye opening
• Genetic conditions: epicanthal folds appear alongside several other examination findings

Photographs are not a reliable way to distinguish pseudostrabismus from true strabismus. Camera angle, side gaze, shadows, and an off-centre flash can change how the eyes look. A white pupil in repeated photographs is different from a simple epicanthal fold and needs prompt medical assessment.

A child whose eye appears to turn should have an eye-alignment check, even if epicanthal folds seem to explain the appearance. This is usually a routine or prompt appointment rather than an emergency.

Seek urgent medical assessment for a new, constant eye turn, a new drooping eyelid, double vision, or a white-looking pupil. Sudden loss of vision, severe eye pain, major eye injury, or a chemical splash requires emergency eye care. These symptoms are not expected effects of epicanthal folds.

If the folds are simply part of your or your child’s usual appearance and there are no vision concerns, there may be nothing you need to do.

Children should still receive routine vision screening offered through primary care, school, or local child health services. Screening checks more than appearance and may identify problems that are not obvious at home.

If an eye seems to turn, ask whether the alignment has been checked with tests such as the corneal light reflex test or a cover test. The light reflex test compares where light reflects from each eye. The cover test checks whether either eye moves when the other is covered.

You can keep dated photographs if an eye turn seems intermittent. Images taken straight on, with the child looking toward the camera, may help show when it happens. They cannot confirm a diagnosis, but they can give the eye-care professional useful context.

Arrange a routine assessment with a primary care clinician, optometrist, or ophthalmologist if:

• The eyes often appear to point in different directions
• The appearance is becoming more noticeable
• There is a family history of childhood strabismus or amblyopia
• A child closes one eye, tilts their head, or has difficulty seeing
• You remain concerned despite reassurance from photographs or casual observation

Surgery is not medically needed for a normal epicanthal fold. Eyelid surgery may occasionally be considered for a diagnosed eyelid disorder or for cosmetic reasons. It can cause scarring, asymmetry, or changes to eyelid function, so it requires an individual discussion with an appropriately trained specialist.

Are epicanthal folds normal in babies?

Yes. They are common in infancy, when the nasal bridge is relatively low and broad. The folds may become less prominent as the face grows.

Do they mean a baby has Down syndrome?

No. Epicanthal folds can be present in people with Down syndrome, but they are also a common normal feature in people without it. A diagnosis cannot be made from one facial feature.

Can epicanthal folds make the eyes look crossed?

Yes. They can hide part of the inner white area of the eye and create the appearance of inward turning. This is called pseudostrabismus. An eye examination is needed if there is uncertainty because true strabismus can look similar.

Do epicanthal folds affect eyesight?

A typical fold does not cover the pupil or reduce vision. Any vision problem should be assessed separately rather than assumed to come from the fold.

Will they disappear?

They may become less noticeable as a child’s nasal bridge develops. They may also remain into adulthood as a normal inherited feature. There is no need for them to disappear.

Is genetic testing needed?

Not for an isolated epicanthal fold in an otherwise healthy person. Testing may be considered when there are other specific findings, developmental concerns, or a relevant family history. A clinical genetics service can explain what a test could and could not show.