ldentify the visual defect shown in the photograph below ?
A. Right homonymous hemianopia.
B. Right homonymous hemianopia.
C. Right inferior homonymous quadrantanopia.
D. Right incongruous hemianopia.
Ans:C. Right inferior homonymous quadrantanopia.
Types of visual field loss
- This is a defect surrounded by normal visual field. It may begin as a gradual enlargement of the blind spot.
- Relative scotoma – an area where objects of low luminance cannot be seen but larger or brighter ones can.
- Absolute scotoma – nothing can be seen at all within that area.
- This is a binocular visual defect in each eye’s hemifield.
- Bitemporal hemianopia – the two halves lost are on the outside of each eye’s peripheral vision, effectively creating a central visual tunnel.
- Homonymous hemianopia – the two halves lost are on the corresponding area of the visual field in both eyes, i.e either the left or the right half of the visual field.
- Quadrantanopia – this is an incomplete hemianopia referring to a quarter of the schematic ‘pie’ of visual field loss.
- Right homonymous inferior quadrantanopia : Both lower right quadrants of the visual field experience loss of visual function; the cause of this visual defect is commonly located in the left hemisphere.
- Left homonymous inferior quadrantanopia involves visual defects in the lower left quadrant of each eye, with the cause usually being located in the right hemisphere of the brain.
|Loss of vision in one eye||Ipsilateral Optic Nerve|
|Bitemporal Hemianopia||Optic chiasm|
|Binasal hemianopia||Optic chiasm|
|Left homonymous hemianopia||Right optic tract / radiation|
|Right homonymous hemianopia||Left optic tract / radiation|
Contralateral optic radiation