Search results
Results from the WOW.Com Content Network
An eyelid is a thin fold of skin that covers and protects the eye. The levator palpebrae superioris muscle helps in the movement of eyelid. The human eyelid features a row of eyelashes along the eyelid margin, which helps in protection of the eye from dust and foreign debris. The main function of eyelid is to keep the cornea moist and clean.
Eyelid edema is a condition in which the eyelids are swollen and tissues contain excess fluid. It may affect eye function when it increases the intraocular pressure. Eyelid edema is caused by allergy, trichiasis or infections. [4] The main symptoms are swollen red eyelids, pain, and itching. Chronic eyelid edema can lead to blepharochalasis.
An epicanthic fold or epicanthus [6] is a skin fold of the upper eyelid that covers the inner corner (medial canthus) of the eye. [3] However, variation occurs in the nature of this feature and the presence of "partial epicanthic folds" or "slight epicanthic folds" is noted in the relevant literature.
The human eye is a sensory organ in the visual system that reacts to visible light allowing eyesight. Other functions include maintaining the circadian rhythm, and keeping balance. Arizona Eye Model. "A" is accommodation in diopters. The eye can be considered as a living optical device.
The corneal reflex, also known as the blink reflex or eyelid reflex, [1] is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), though it could result from any peripheral stimulus. Stimulation should elicit both a direct and consensual response (response of the opposite eye).
The tarsi (sg.: tarsus) or tarsal plates are two comparatively thick, elongated plates of dense connective tissue, about 10 mm (0.39 in) in length for the upper eyelid and 5 mm for the lower eyelid; one is found in each eyelid, and contributes to its form and support.
Blinking is a bodily function; it is a semi-autonomic rapid closing of the eyelid. [1] A single blink is determined by the forceful closing of the eyelid or inactivation of the levator palpebrae superioris and the activation of the palpebral portion of the orbicularis oculi, not the full open and close.
Surface ectoderm forms the lens, corneal epithelium and eyelid. The extracellular mesenchyme forms the sclera , the corneal endothelium and stroma , blood vessels , muscles , and vitreous . The eye begins to develop as a pair of optic vesicles on each side of the forebrain at the end of the fourth week of pregnancy.