quadrantanopia
Học thuậtThân thiện
Definition
Noun: A specific type of partial blindness or visual field loss affecting one quarter (a quadrant) of the visual field in one or both eyes. It is a neurological visual defect.
Usage
This is a medical and technical term used primarily in ophthalmology, neurology, and optometry to describe a precise pattern of vision loss. * It is used to specify the location and extent of a visual field defect. * It is often documented in patient records and clinical reports.
Examples
- The MRI scan revealed a lesion that caused quadrantanopia in the patient's lower left visual field.
- After the stroke, she was diagnosed with homonymous quadrantanopia.
- Quadrantanopia can significantly impact activities like reading and driving.
Advanced Usage
- The term is often modified to specify the affected quadrant:
- Superior quadrantanopia: Loss in the upper quarter of the visual field.
- Inferior quadrantanopia: Loss in the lower quarter.
- Homonymous quadrantanopia: Loss in the same quadrant of both eyes (e.g., left upper quadrant in both the right and left eye), typically indicating a problem in the brain's visual pathway.
- Heteronymous quadrantanopia: Loss in different quadrants of each eye, which is less common.
Variants and Related Words
- Hemianopia (noun): Blindness in one half of the visual field, a related but more extensive condition.
- Scotoma (noun): A smaller, spot-like area of lost or depressed vision within the visual field.
Synonyms
- Quadrantanopsia (an alternative spelling with the same meaning).
- Partial visual field loss.
- Sector visual field defect.
Antonyms
- Full visual field.
- Normal vision.
Notes
- Quadrantanopia is a compound word formed from "quadrant" (a quarter) and "anopia" (absence of sight).
- It is a precise diagnostic term and is not used in everyday conversation. In non-medical contexts, one might describe the symptom as "partial blindness" or "loss of side vision."
Noun
- blindness in one fourth of the visual field