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The lacrimal gland is a compound tubuloacinar gland, it is made up of many lobules separated by connective tissue, each lobule contains many acini.The acini composed of large serous cells which, produce a watery serous secretion, serous cells are filled with lightly stained secretory granules and surrounded by well-developed myoepithelial cells and a sparse, vascular stroma.
The second type of tears results from irritation of the eye by foreign particles, or from the presence of irritant substances such as onion vapors, perfumes and other fragrances, tear gas, or pepper spray in the eye's environment, including the cornea, conjunctiva, or nasal mucosa, which trigger TRP channels in the ophthalmic nerve.
SUNCT often accompanies cranial autonomic symptoms, including lacrimation (tear flow), ipsilateral ptosis (drooping of the eyelid which is on the same side as the attacks), eyelid edema (swelling due to fluid accumulation), nasal blockage, and conjunctival injection (redness of eye). Depending on which division of the trigeminal nerve ...
The lacrimal apparatus is the physiological system containing the orbital structures for tear production and drainage. [1]It consists of: The lacrimal gland, which secretes the tears, and its excretory ducts, which convey the fluid to the surface of the eye; it is a j-shaped serous gland located in lacrimal fossa.
The lacrimal nerve branches from the ophthalmic nerve immediately before traveling through the superior orbital fissure to enter the orbit. [citation needed]At the superior portion of the lateral wall of the orbit, it also receives a secretomotor [2]: 495 communicating [2]: 402 parasympathetic [3] branch from the zygomaticotemporal nerve [2]: 495 for the lacrimal gland.
Tears, from the lacrimal glands, collect in this sac during excessive lacrimation. The fluid then flows through the nasolacrimal duct and into the nasopharynx. This drainage results in what is commonly referred to a runny nose during excessive crying or tear production. Injury or fracture of the lacrimal bone can result in posttraumatic ...
Causes of epiphora are any that cause either overproduction of tears or decreased drainage of tears, resulting in tearing onto the cheek. [2] This can be due to ocular irritation and inflammation (including trichiasis and entropion) or an obstructed tear outflow tract, which is divided according to its anatomical location (i.e., ectropion, punctal, canalicular or nasolacrimal duct obstruction).
The lacrimal sac or lachrymal sac [1] is the upper dilated end of the nasolacrimal duct, [2] and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla.