visual field defect
Partial or complete loss of vision in specific areas of the visual field, often resulting from stroke or brain lesions affecting visual processing pathways.
Full Definition
Visual field defects refer to areas of reduced or absent vision within the normal field of view, typically caused by damage to the visual pathways in the brain rather than the eyes themselves. These defects can manifest as hemianopias (loss of half the visual field), quadrantanopias (loss of a quarter), or scotomas (blind spots). In neuropsychological practice, visual field defects are crucial to identify as they can significantly impact cognitive test performance and daily functioning. Common patterns include homonymous hemianopia following stroke, where corresponding halves of both visual fields are affected. Assessment typically involves confrontation testing or formal perimetry, and results must be considered when interpreting other cognitive measures.
Usage
Usage note: Always specify the type and extent of defect; distinguish from visual neglect or attention deficits.
In Context
- "Confrontation testing revealed a left homonymous hemianopia, which was accommodated during subsequent cognitive assessment." — neuropsychological evaluation
- "The patient's poor performance on visuospatial tasks was attributed to an underlying visual field defect rather than cognitive impairment." — clinical case note