Search results
Results from the WOW.Com Content Network
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. It connects the lacrimal canaliculi , which drain tears from the eye's surface, and the nasolacrimal duct , which conveys this fluid into the nasal cavity. [ 3 ]
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.
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 caruncle is found at the medial canthus of the eye. [1] It consists of skin, hair follicles, sebaceous glands, sweat glands, accessory lacrimal tissue and other tissues that are present in the skin and accessory lacrimal glands. [1] [2] Its non-keratinized epithelium resembles the conjunctival epithelium. [2]
However, in the same study, cysts were detected in the muscle of only one of 102 dogs. [66] In China, where dogs are slaughtered for human consumption, trichinae were detected in an average of 16.2% of slaughtered dogs during trichinae inspection, with prevalence varying from 1.2% to 44.8% depending on the region. [67]
Specifically, the lacrimal bones help form the nasolacrimal canal necessary for tear translocation. A depression on the anterior inferior portion of one bone, the lacrimal fossa, houses the membranous lacrimal sac. Tears, from the lacrimal glands, collect in this sac during excessive lacrimation.
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.