palpebral aperture

anatomy

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Last updated

July 1, 2026

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The palpebral aperture is the almond-shaped opening between the eyelids when the eye is open. This aperture is crucial for keeping the cornea moist by allowing the eyelids to sweep secretions over its surface during waking hours. The eyelids themselves are folds of tissue that protect the eye from foreign bodies and prevent evaporation during sleep. The aperture's edges are called canthi, with the inner canthus being closer to the nose and the outer canthus on the other side. The eyelids have four layers: skin, muscle, a fibrous layer for stability, and the conjunctiva.123

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human eye
The eyelids
…between the lids, called the palpebral aperture; and (4) the innermost layer of the lid, a portion of the conjunctiva. The conjunctiva is a mucous membrane that serves to attach the eyeball to the orbit and lids but permits a considerable degree of rotation of the eyeball in the orbit.
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…between the lids, called the palpebral aperture; and (4) the innermost layer of the lid, a portion of the conjunctiva. The conjunctiva is a mucous membrane that serves to attach the eyeball to the orbit and lids but permits a considerable degree of rotation of the eyeball in the orbit.
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