Visual pathway starting from retina consists of optic nerve , optic chiasma , optic tracts , lateral geniculate bodies , optic radiations and the visual cortex .
`~ Pratheek Prabhu
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| Courtesy :- Comprehensive Ophthalmology 6th edition ; AK Khurana ; Pg.314 |
Sl . no
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Site of lesion
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Type of lesion
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1
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Optic nerve
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Complete blindness on ipsilateral side
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2
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Anterior Chiasma
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Junctional scotoma
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3
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Central chiasma
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Bitemporal hemianopia
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4
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Lateral chiasma
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Binasal hemianopia
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5
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Optic tracts / LBG
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Incongruous homonymous hemianopia
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6
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Part of optic radiations in temporal lobe
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Superior quadrant hemianopia (pie in sky )
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7
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Part of optic radiations in parietal lobe
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Inferior quadrant hemianopia (pie on floor )
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8
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Optic radiations
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Complete homonymous hemianopia
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9
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Visual cortex sparing macula
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Congruous homonymous hemianopia
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10
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Visual cortex , only macula
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Congruous homonymous macular defect
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11
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Bilateral Visual cortex , only macula
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Bilateral homonymous macular defect
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could you please tell why the lesion at proximal part of optic nerve (labelled '2' in the pic) would lead to ipsilateral central scotoma?
ReplyDeleteFrom my understanding, the lesion should lead to ipilateral complete blindness and contralateral temporal hemianopia.
also, a compressive lesion would affect the peripheral fibres of optic nerve first. and these fibres are carrying signals from peripheral retina, right?..
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