Superior quadranopia = temporal lobe lesion
Inferior quadranopia = parietal lobe lesion
Inferior quadranopia = parietal lobe lesion
Parietal lesions cause a contralateral inferior quadranopia.
Visual field defects
- left homonymous hemianopia means visual field defect to the left, i.e. Lesion of right optic tract
- homonymous quadrantanopias: PITS (Parietal-Inferior, Temporal-Superior)
- incongruous defects = optic tract lesion; congruous defects = optic radiation lesion or occipital cortex
Homonymous hemianopia
- Incongruous defects: lesion of optic tract
- Congruous defects: lesion of optic radiation or occipital cortex
- Macula sparing: lesion of occipital cortex
Homonymous quadrantanopias
- Superior: lesion of temporal lobe
- Inferior: lesion of parietal lobe
- Mnemonic = PITS (Parietal-Inferior, Temporal-Superior)
Bitemporal hemianopia
- Lesion of optic chiasm
- Upper quadrant defect > lower quadrant defect = inferior chiasmal compression, commonly a pituitary tumour
- Lower quadrant defect > upper quadrant defect = superior chiasmal compression, commonly a craniopharyngioma
