optic chiasma
Học thuậtThân thiện
Definition
- Noun:
- The crossing of the optic nerves from the two eyes at the base of the brain: The optic chiasma is a specific anatomical structure where the optic nerves partially cross. This crossing allows visual information from each eye to be processed by both hemispheres of the brain.
Usage
- The term "optic chiasma" is used exclusively in anatomical, medical, and biological contexts to describe this precise neural structure.
- It is a singular noun. The plural form is "optic chiasmata" or, more commonly, "optic chiasms."
Examples
- Noun:
- The surgeon was careful to avoid damaging the patient's optic chiasma during the procedure.
- A tumor pressing on the optic chiasma can cause specific visual field defects.
- In human anatomy, the optic chiasma is located just below the hypothalamus.
Advanced Usage
- "Lesion at the optic chiasma": Refers to damage or an abnormality at the site of the optic chiasm, often discussed in neurology and ophthalmology.
- The MRI revealed a small lesion at the optic chiasma, explaining the patient's bitemporal hemianopia.
Variants and Related Words
- Optic chiasm (n): A more common variant term with identical meaning.
- Chiasma (n): The general term for an X-shaped crossing or intersection, especially of nerves or chromosomes. The optic chiasma is a specific type of chiasma.
- Optic tract (n): The neural pathway that continues from the optic chiasma to the brain's visual centers.
Synonyms
- Chiasma opticum: The Latin-derived anatomical term.
- Optic decussation: A less common synonym emphasizing the crossing (decussation) of the nerve fibers.
Related Terms and Concepts
- Visual field defect: A loss of part of the normal field of vision, which can result from pressure on the optic chiasma.
- Bitemporal hemianopia: A specific visual field defect where the outer halves of the visual field from both eyes are lost, classically associated with damage to the central portion of the optic chiasma.
Noun
- the crossing of the optic nerves from the two eyes at the base of the brain