hemianopia
Học thuậtThân thiện
Definition
Noun: * Hemianopia: A specific type of vision loss, known as blindness, that affects exactly one half (the left or right side) of the visual field in one or both eyes. It is a neurological condition, not an issue with the eye itself.
Usage
- Hemianopia is a medical term used by healthcare professionals to diagnose and describe a specific visual field defect.
- It is often a symptom resulting from damage to the brain's visual pathways, such as from a stroke, tumor, or head injury.
Examples
- The patient's stroke resulted in hemianopia, causing him to ignore objects on his left side.
- Hemianopia can make activities like reading or crossing the street particularly challenging.
- The neurologist confirmed the presence of left-sided hemianopia following the brain scan.
Advanced Usage
- The term is often specified further based on which half of the vision is lost:
- Homonymous hemianopia: Loss of the same half (e.g., the right side) in both eyes.
- Heteronymous hemianopia: Loss of different halves (e.g., the outer halves) in each eye, which can be bitemporal (loss of the outer, temporal halves) or binasal (loss of the inner, nasal halves).
Variants and Related Words
- Hemianopsia (noun): A less common variant spelling with the same meaning.
- Hemianopic (adjective): Relating to or affected by hemianopia.
- Example: The patient has a hemianopic visual field defect.
Synonyms
- Hemianopsia
- Half-blindness (a more general, non-medical term)
- Visual field cut or visual field defect (broader terms that include hemianopia)
Antonyms
- Full visual fields
- Normal vision (in the context of visual field assessment)
Related Medical Terms (Not Synonyms)
- Quadrantanopia: Blindness in one quarter of the visual field, which is a less extensive defect than hemianopia.
- Scotoma: A smaller, spot-like area of blindness within the visual field.
- Agnosia: A separate condition involving the inability to recognize objects, which can sometimes co-occur with hemianopia.
Noun
- blindness in one half of the visual field of one or both eyes