palpebral fissure

Orifice separating upper and lower eyelids. In the human adult this measures about 10mm vertically and 30 mm horizontally. It can be reduced in size in fetal alcohol syndrome. In Trisomy 9 the palpebral fissures can be upslanting. [WP,modified]. Every claim on this page comes from the Leumas anatomy graph and carries its source.

What the palpebral fissure is

Orifice separating upper and lower eyelids. In the human adult this measures about 10mm vertically and 30 mm horizontally. It can be reduced in size in fetal alcohol syndrome. In Trisomy 9 the palpebral fissures can be upslanting. [WP,modified]. The atlas records it as a organ at the organ scale in the human body.

Where the palpebral fissure is

It sits in the head, within the sensory system. Not positioned individually. Drawn inside the structure this dataset says contains it — the containment is asserted, the exact spot within it is not.

What the palpebral fissure connects to

The atlas records 6 typed relationships for it, across 4 kinds of connection. part of camera-type eye.

Supply and innervation

This dataset asserts no arterial supply, venous drainage or innervation for the palpebral fissure. Only a minority of structures carry those edges here, so an empty answer means nothing has been recorded — not that there is nothing to record.

Also called

Also recorded as rima palpebrarum. Searching any of those names reaches this page.

Source

Uberon multi-species anatomy ontology (Mungall et al.), CC BY 4.0. Term UBERON:0001819, version 2026-06-19, retrieved 2026-08-24. Licence: CC-BY-4.0.

• Part of: camera-type eye.
• A kind of: orifice.
• Adjacent to: lower eyelid and upper eyelid.
• overlaps: inner canthus and outer canthus.

Questions

Where is the palpebral fissure?

It sits in the head, within the sensory system. Not positioned individually. Drawn inside the structure this dataset says contains it — the containment is asserted, the exact spot within it is not.

What does the palpebral fissure connect to?

Part of: camera-type eye.

Is the palpebral fissure the same in other species?

Leumas holds the same relationship vocabulary for every species it carries, so where another dataset records this structure you can put the two side by side on /compare.