optic disk
Học thuậtThân thiện
The optic disk is a pale circular area at the back of the eye where blood vessels converge.
Definition
Noun: - The point where the optic nerve enters the retina; not sensitive to light: The optic disk is a specific anatomical structure in the back of the eye where retinal ganglion cell axons converge to form the optic nerve. This area lacks photoreceptor cells (rods and cones), making it insensitive to light and creating a natural blind spot in the visual field of each eye.
Usage
- The term is used in medical, biological, and optometric contexts to describe a key part of the eye's anatomy.
- It is a technical noun, typically used in singular form.
- Example:
- Example:
Advanced Usage
- In clinical reports, the condition of the optic disk is a critical indicator of eye health. Changes in its appearance can signal diseases like glaucoma or optic neuritis.
- Example: Cupping of the optic disk is a hallmark sign of advanced glaucoma.
Variants and Related Words
- Optic nerve head: A direct synonym often used interchangeably in clinical settings.
- Blind spot: A related functional term describing the area in the visual field corresponding to the light-insensitive optic disk.
- Optic cup: The central depression within the optic disk.
Synonyms
- Optic nerve head
- Blind spot (in the specific anatomical sense)
- Papilla (less common)
Related Phrases
- Optic disk edema: Swelling of the optic disk.
- Example: The patient was diagnosed with optic disk edema due to increased intracranial pressure.
- Optic disk pallor: Paleness of the optic disk, often indicating optic nerve atrophy.
- Example: Optic disk pallor was observed, suggesting possible previous optic nerve damage.
The optic disk is a pale circular area at the back of the eye where blood vessels converge.
Noun
- the point where the optic nerve enters the retina; not sensitive to light