Boards Ocular Anatomy. Eyelid and Eyebrows.

An abnormally increased distance between the medial canthi of the eyelids

Whitening of eyelashes

Loss of eyelashes

Turning inward of eyelashes, often secondary to entropian

Infection of the eyelashes caused by phthirus pubis. Sympoms include chronic itching and irritation.

Contains fine hairs, sweat, and sebaceous glands. unique because it is the thinnest skin in the body and contains no fat.

Thin layer of loose connective tissue that lies between the outer skin and underlying orbicularis

Contains palpebral portion of the orbicularis oculi. This is one of the muscles of facial expression innervated by CNVII. Paralysis causes lower eyelid to droop away from the globe, resulting in ectropian.

1. Orbital portion. Attaches to orbital margins and extends outward. Used for forced closure of the eyelids. 2. Palpebral portion. Used for spontaneous and reflex blinking. Contains two specialized areas: Muscle of Riolan and Muscle of Horner

In the palpebral portion of the orbicularis oculi (eyelid). Most superficial portion of the orbicularis oculi. Keeps lid margin tightly applied to globe during eye movements. May contribute to rotating the eyelashes toward the eye during eyelid closure. Lack of sympathetic innervation to this muscle during Horner's syndrome can lead to a reverse ptosis of the lower lid.

Fibers from the orbicularis in the palpebral portion of the eyelid. Helps drain tears into the lacrimal sack.

Dense irregular connective tissue ( in upper and lower eyelid) that serves as a barrier. The orbital septum restricts fat from falling down onto the lid margin and more importantly keeps infections localized to the anterior portion of the eyelid, away from the orbit.

The periorbita and periostium of the skull surface. The periorbita loosely cover the orbital bones (anterior is the orbital septum and posterior fuses with dura of optic nerve.

Posterior lacrimal crest. The lacrimal sac is anterior to this attachment, meaning the orbital septum does NOT protect the lacrimal sac from infection.

Infection that occurs anterior to the orbital septum.