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Lacrimal Papilla
The lacrimal papilla is the small rise in the bottom (inferior) and top (superior) eyelid just before it ends at the corner of the eye closest to the nose. At the medial edge of it is the lacrimal punctum, a small hole that lets tears drain into the inside of the nose through the lacrimal canaliculi. In medical terms, the lacrimal papilla is a small conical elevation on the margin of each eyelid at the basal angles of the lacrimal lake. Its apex is pierced by a small orifice, the lacrimal punctum The lacrimal punctum (plural ''puncta'') or lacrimal point, is a minute opening on the summits of the lacrimal papillae, seen on the margins of the eyelids at the lateral extremity of the lacrimal lake. There are two lacrimal puncta in the medial ..., the commencement of the lacrimal canaliculi. It is otherwise known commonly as simply the 'tear duct'. See also * Papilla (other) References External links Description at uams.edu Human eye anatomy {{eye-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canthus
The canthus (pl. canthi, palpebral commissures) is either corner of the eye where the upper and lower eyelids meet. More specifically, the inner and outer canthi are, respectively, the medial and lateral ends/angles of the palpebral fissure. The bicanthal plane is the transversal plane linking both canthi and defines the upper boundary of the midface. Etymology The word ' is the Latinized form of the Ancient Greek ('), meaning 'corner of the eye'. Population distribution The eyes of those of East Asian and some Southeast Asian people tend to have the inner canthus veiled by the epicanthus. In the Caucasian or double eyelid, the inner corner tends to be exposed completely. Commissures * The ''lateral palpebral commissure'' (commissura palpebrarum lateralis; external canthus) is more acute than the medial, and the eyelids here lie in close contact with the bulb of the eye. * The ''medial palpebral commissure'' (commissura palpebrarum medialis; internal canthus) is prolonged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Punctum
The lacrimal punctum (plural ''puncta'') or lacrimal point, is a minute opening on the summits of the lacrimal papillae, seen on the margins of the eyelids at the lateral extremity of the lacrimal lake. There are two lacrimal puncta in the medial (inside) portion of each eyelid. Normally, the puncta dip into the lacrimal lake. Together, they function to collect tears produced by the lacrimal glands. The fluid is conveyed through the lacrimal canaliculi to the lacrimal sac, and thence via the nasolacrimal duct to the inferior nasal meatus of the nasal passage. Additional images File:Lacrimal punctum.jpg, A close up of a lacrimal punctum. File:Lower lacrimal punctum.jpg, Lower lacrimal punctum through slit lamp biomicroscope See also * Imperforate lacrimal punctum *Lacrimal apparatus The lacrimal apparatus is the physiological system containing the Orbit (anatomy), orbital structures for tears, tear production and drainage.Cassin, B. and Solomon, S. ''Dictionary of Eye Termino ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Canaliculi
The lacrimal canaliculi, (sing. canaliculus), are the small channels in each eyelid that drain lacrimal fluid, from the lacrimal puncta to the lacrimal sac. This forms part of the lacrimal apparatus that drains lacrimal fluid from the surface of the eye to the nasal cavity. Structure There is a single lacrimal canaliculus in each eyelid, a superior lacrimal canaliculus in the upper eyelid and an inferior lacrimal canaliculus in the lower eyelid. The canaliculi travel vertically and then turn medially to travel towards the lacrimal sac. At the bend, the canaliculus is dilated and called the ampulla. Usually, the superior and inferior lacrimal canaliculi join to form a common passage that enters the lateral wall of the lacrimal sac. Superior lacrimal canaliculus The superior lacrimal canaliculus is located in the upper eyelid. It first ascends, then bends medially towards the lacrimal sac. It drains lacrimal fluid from the superior lacrimal punctum. It is smaller and shorter th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eyelid
An eyelid 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. The human eyelid features a row of eyelashes along the eyelid margin, which serve to heighten the protection of the eye from dust and foreign debris, as well as from perspiration. "Palpebral" (and "blepharal") means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist. They keep the eyes from drying out when asleep. Moreover, the blink reflex protects the eye from foreign bodies. The appearance of the human upper eyelid often varies between different populations. The prevalence of an epicanthic fold covering the inner corner of the eye account for the majority of East Asian and Southeast Asian populations, and is also found i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Lake
The lacrimal lake is the pool of tears in the lower conjunctival cul-de-sac, which drains into the opening of the tear drainage system (the ''puncta lacrimalia''). The volume of the lacrimal lake has been estimated to be between 7 and 10 μL. Although the lacrimal lake usually contains 7–10 μL of tears, the maximum fluid it can usually hold is 25–30 μL before tearing occurs. Aging usually causes the eyelids to become more loose which in turn enables the lacrimal lake to hold even more fluid. The lacrimal papilla is an elevation located on the medial canthus where the punctum is found. See also *Dry eye syndrome *Lacrimal apparatus The lacrimal apparatus is the physiological system containing the orbital structures for tear production and drainage.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. It consist ... * Medial palpebral commissure References {{Authority control Human eye anatomy es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papilla (other)
Papilla (Latin, 'nipple') or papillae may refer to: In animals * Papilla (fish anatomy), in the mouth of fish * Basilar papilla, a sensory organ of lizards, amphibians and fish * Dental papilla, in a developing tooth * Dermal papillae, part of the skin * Major duodenal papilla, in the duodenum * Minor duodenal papilla, in the duodenum * Genital papilla, a feature of the external genitalia of some animals * Interdental papilla, part of the gums * Lacrimal papilla, on the bottom eyelid * Lingual papillae, small structures on the upper surface of the tongue * Renal papilla, part of the kidney In plants and fungi * Papilla (mycology), a nipple-shaped protrusion in the center of the cap * Stigmatic papilla, part of the stigma (botany) See also * * * Blister, a small pocket of body fluid within the upper layers of the skin * Papillary muscle, a muscle in the heart * Papilloma, a benign epithelial tumor * Papule A papule is a small, well-defined bump in the skin. It may have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
