hem·i·a·nop·si·a (h m  - -n p s-) or hem·i·a·no·pi·a (-n p-)n. Loss of vision in one half of the visual field of one or both eyes. hem i·a·noptic (-npt k) adj. |
hemianopia, hemianopsia.
See hemiamblyopia.
hemianopsia
hemianopia.
hemianopia
Loss of vision in one half of the visual field of one eye (unilateral hemianopia) or of both eyes (bilateral hemianopia) (Fig. H1). Syn. hemianopsia. See quadrantanopia; hemianopic pupillary reflex.
absolute hemianopia Hemianopia in which the affected part of the retina is totally blind to light, form and colour.
altitudinal hemianopia Hemianopia in either the upper or lower half of the visual field. A common cause is anterior ischaemic optic neuropathy.
binasal hemianopia Hemianopia in the nasal halves of the visual fields of both eyes.
bitemporal hemianopia Hemianopia in the temporal halves of the visual fields of both eyes.
congruous hemianopia Hemianopia in which the defects in the two visual fields are identical. A common cause is a lesion in the posterior optic radiations.
heteronymous hemianopia A loss of vision in either both nasal halves (binasal hemianopia) or both temporal halves of the visual field (bitemporal hemianopia). A common cause of the latter is a lesion in the optic chiasma.
homonymous hemianopia A loss of vision in the nasal half of the visual field of one eye and the temporal half of the visual field of the other eye. Left homonymous hemianopia is a loss of vision in the temporal half of the visual field of the left eye and the nasal half of the visual field of the right eye. Right homonymous hemianopia is a loss of vision in the temporal half of the visual field of the right eye and the nasal half of the visual field of the left eye. Common causes are occlusion of the posterior cerebral artery (stroke), trauma and tumours. See macular sparing.
incongruous hemianopia Hemianopia in which the defects in the two affected visual fields differ in one or more ways. A common cause is a lesion of the optic tract.
quadrantic hemianopia See quadrantanopia.
relative hemianopia Hemianopia involving a loss of form and colour but not of light.
hemianopia spectacles See hemia-nopic spectacles.
absolute hemianopia Hemianopia in which the affected part of the retina is totally blind to light, form and colour.
altitudinal hemianopia Hemianopia in either the upper or lower half of the visual field. A common cause is anterior ischaemic optic neuropathy.
binasal hemianopia Hemianopia in the nasal halves of the visual fields of both eyes.
bitemporal hemianopia Hemianopia in the temporal halves of the visual fields of both eyes.
congruous hemianopia Hemianopia in which the defects in the two visual fields are identical. A common cause is a lesion in the posterior optic radiations.
heteronymous hemianopia A loss of vision in either both nasal halves (binasal hemianopia) or both temporal halves of the visual field (bitemporal hemianopia). A common cause of the latter is a lesion in the optic chiasma.
homonymous hemianopia A loss of vision in the nasal half of the visual field of one eye and the temporal half of the visual field of the other eye. Left homonymous hemianopia is a loss of vision in the temporal half of the visual field of the left eye and the nasal half of the visual field of the right eye. Right homonymous hemianopia is a loss of vision in the temporal half of the visual field of the right eye and the nasal half of the visual field of the left eye. Common causes are occlusion of the posterior cerebral artery (stroke), trauma and tumours. See macular sparing.
incongruous hemianopia Hemianopia in which the defects in the two affected visual fields differ in one or more ways. A common cause is a lesion of the optic tract.
quadrantic hemianopia See quadrantanopia.
relative hemianopia Hemianopia involving a loss of form and colour but not of light.
hemianopia spectacles See hemia-nopic spectacles.
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Fig. H1 Complete, bitemporal hemianopia due to a large pituitary tumour compressing the optic chiasma
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