An eyelid (/ ˈ aɪ. l ɪ d / EYE-lid) is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily.

Jul 11, 2019 · The palpebral fissure refers to the normal exposed area between upper and lower eyelids. The palpebral fissure vertical height (PFH) is measured between the margin of the lower eyelid to the margin of the upper eyelid. The normal palpebral fissure height is 8-11 mm. This is a key measurement that you need when assessing for ptosis.

Oct 25, 2020 · The eyelids are split into upper and lower portions, which meet at the medial and lateral canthi of the eye. The opening between the two eyelids is called the palpebral aperture or opening. In this article, we shall look at the anatomy of …

Dec 22, 2022 · There are seven extraocular muscles – the levator palpebrae superioris, superior rectus, inferior rectus, medial rectus, lateral rectus, inferior oblique and superior oblique. Functionally, they can be divided into two groups: Responsible for eye movement – Recti and oblique muscles.

Nov 11, 2024 · Eyelids play a role in facial expressions and provide cues about a person’s wakefulness and attention. Extends downward from the eyebrow and forms the top boundary of the eye opening (palpebral fissure). Extends upward to meet the skin of the cheek, creating the lower boundary of the eye opening.

Nov 3, 2023 · Levator palpebrae superioris is a triangular muscle that extends along the roof of the orbit, from the apex of orbit to the superior eyelid. It originates with a short and narrow tendon from the inferior aspect of the lesser wing of sphenoid bone, …

Feb 18, 2023 · The layer of striated muscles in the upper eyelid contains levator palpebrae superioris muscle (LPS) which is supplied by a branch of the oculomotor nerve. The main function of LPS is to raise the upper eyelid.

One of the two movable folds covering the front of the eyeball when closed; formed of a fibrous core (tarsal plate) and the palpebral portions of the orbicularis oculi muscle covered with skin on the superficial, anterior surface and lined with conjunctiva on the deep, posterior surface; rapid contraction of the contained muscle fibers produces ...

Nov 3, 2023 · Six extraocular muscles move the eye: superior rectus, inferior rectus, medial rectus, lateral rectus, superior oblique and inferior oblique muscles; and one other, levator palpebrae superioris, opens the eyelid. Don’t understand how all these muscles work? You can find out everything about them in the following learning materials.

Here, two striated /voluntary muscles are situated , namely the ORBICULARIS MUSCLE and the LEVATOR PALPEBRAE SUPERIORIS MUSCLE. The orbicularis muscle has fibres oriented in a circular fashion around the eye and the orbit. It has two parts:- ORBITAL PART : Part of orbicularis situated in front of the orbital rims is called the orbital part.