hemianopia
Pronunciation: hem-ee-uh-NOH-pee-uh
Loss of vision in half of the visual field, typically indicating damage to the optic pathways posterior to the optic chiasm.
Full Definition
Hemianopia refers to the loss of vision in one half of the visual field in one or both eyes. The most common type is homonymous hemianopia, where the same half of the visual field is affected in both eyes, typically resulting from stroke or other lesions affecting the optic tract, lateral geniculate nucleus, or visual cortex. Bitemporal hemianopia affects the outer halves of both visual fields and often indicates chiasmal pathology. This condition significantly impacts daily activities and requires careful documentation in neurological assessments. The pattern of visual field loss provides crucial localizing information for the underlying pathology.
Usage
Usage note: Specify whether homonymous, bitemporal, or other pattern; distinguish from quadrantanopia (quarter-field loss).
In Context
- "Left homonymous hemianopia was detected on confrontation testing and confirmed by formal perimetry." — Stroke assessment
- "The patient's bitemporal hemianopia suggested a pituitary adenoma compressing the optic chiasm." — Neuro-ophthalmology consultation