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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.
Tears are produced by the lacrimal gland, situated just outside the eye. Blinking the eyelids distributes the tears to keep the eyes moist, clean and lubricated. Excess tears are drained via the punctum through the tiny channels called canaliculi located on the inner side of the eyes into the tear sac, from there to the tear duct, the nose and finally down the throat.
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.
Human tears. Tears are a clear liquid secreted by the lacrimal glands (tear gland) found in the eyes of all land mammals. [1] Tears are made up of water, electrolytes, proteins, lipids, and mucins that form layers on the surface of eyes. [2] The different types of tears—basal, reflex, and emotional—vary significantly in composition. [2]
The canal containing the duct is called the nasolacrimal canal.It is formed by indentations in the inferior nasal conchae, maxilla and lacrimal bone.The canal drains into the nasal cavity through the anterior portion of the inferior meatus, which is between the inferior concha and the floor of the nasal cavity.
Involutional stenosis is probably the most common cause of nasolacrimal duct obstruction in older people. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the nasolacrimal duct is caused by inflammatory infiltrates and edema.
This procedure is indicated when there is recurrent swelling and pain on the face but ultrasound has not revealed any problems. If Sjögren syndrome (also known as Sicca syndrome, an autoimmune disease that affects the lacrimal and salivary glands, causing reduced tears and saliva production) is suspected, this procedure is useful.
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 ...