lacrimal sac
Học thuậtThân thiện
Definition
- Noun:
- A small, dilated structure in the eye's drainage system: The lacrimal sac is a membranous sac located at the inner corner of each eye, at the nasal end of the lacrimal duct. It serves as a reservoir that collects tears secreted by the lacrimal glands before they drain into the nasal cavity.
Usage
- The term is used in anatomical, medical, and biological contexts to describe a specific part of the human tear drainage system.
- It is typically used as a singular noun, but the plural form "lacrimal sacs" refers to the pair of structures.
Examples
- Noun:
- An infection of the lacrimal sac is called dacryocystitis.
- Tears flow from the eye's surface into the lacrimal sac via small canals.
- The surgeon carefully probed the blocked lacrimal sac to restore tear drainage.
Advanced Usage
- "Obstruction of the lacrimal sac": A common condition where the sac becomes blocked, preventing normal tear drainage and often leading to infection or excessive tearing.
- "Lacrimal sac massage": A therapeutic technique sometimes recommended for infants with congenital blockages to help open the duct.
Variants and Related Words
- Nasolacrimal sac: A synonym emphasizing the sac's connection to the nose (naso-).
- Dacryocyst: A medical term synonymous with lacrimal sac, often used in clinical diagnoses (e.g., dacryocystitis).
- Lacrimal apparatus: The collective term for the entire tear-producing and drainage system, which includes the lacrimal glands, ducts, sac, and nasolacrimal duct.
Synonyms
- Dacryocyst (medical term)
- Tear sac (common descriptive term)
Related Phrases
- Lacrimal sac drainage: Refers to the process or surgical procedure for clearing a blocked sac.
- Lacrimal sac tumor: A rare growth or neoplasm within the sac.
Noun
- either of the two dilated ends of the lacrimal ducts at the nasal ends of the eyes that fill with tears secreted by the lacrimal glands