Parts of the Closed Eye

Superior palpebrae

The upper lid is wider than the lower lid. Vertically, it is nearly 3x as large as the lower lid. When naturally closed, it covers the cornea. The lower margin is what forms the line of eye closure. The point of greatest projection for the closed eye is just off center medially.

Inferior palpebrae

The lower lid is narrow and thinner than the upper lid. It follows the curse of the eyeball and inclines from the line of closure. The upper lid overlaps the lower lid at the lateral end of the lower lid.

Line of eye closure

The line that forms between the two eyelids when they are closed, and which marks their place of contact with each other. Occurs in the lower third of the eye socket as a dipping curve. The upper lid covers 2/3, and the lower lid 1/3. The lateral end is inferior and posterior to the medial end. The two lids abut when they close and do not overlap.

Nasal orbital fossa

A triangular concave depression superior to the medial portion of the superior palpebrae.

Superior orbital area

Region between the supercilium and the superior palpebrae. Composed of muscle and fat, it is the deepest near the root of the nose.

Inner canthus

Small elevation extending medially and obliquely from the medial corner of the superior palpebrae. There are no eyelashes here.

Cilia

Eyelashes - the fringe of hair edging the eyelids. Irregular in length and spacing with cilia at the end of the line of eye closure. The cilia on the upper lid turn up, and on the lower lid turn down.

Supercilium

Eyebrows - hair that grows up and outward and is unequal in length. It is denser near the glabella.

Superior palpebral sulcus

The groove or furrow of the superior border of the superior palpebrae - and acquired facial marking.

Inferior palpebral sulcus

The groove or furrow of the inferior border of the inferior palpebral - an acquired facial marking.

Optical facial sulci

The furrows radiating laterally from the lateral corner of the eye - an acquired facial marking.

Oblique palpebral sulcus

The shallow, dark, curving groove below the medial corner of the eyelid. It moves inferior and laterally - a natural facial marking.

Supraorbital margin

The superior rim of the eye socket located on the frontal bone.