Editing Visual field (section)

===Field defects in visual pathway lesions=== 
{{main|Visual pathway lesions}}
{{See also|Visual system}}
[[File:Hemianopsia en.jpg|thumb|350px|right|'''Visual pathway lesions''' <br>
From top to bottom: <br> 1. Complete loss of vision in the right eye <br> 2. Bitemporal hemianopia <br> 3. Homonymous hemianopia <br> 4. Quadrantanopia <br> 5. & 6. Quadrantanopia with [[macular sparing]]]]
The [[visual pathway]] consists of structures that carry visual information from the [[retina]] to the [[brain]]. Lesions in the pathway cause a variety of visual field defects. The type of field defect can help localize where the lesion is located (see figure).
*A lesion in the [[optic nerve]] of one eye causes partial or complete loss of vision in the same eye, with an intact field of vision in other eye. 
*A lesion at the proximal part of [[optic nerve]] of one eye cause, [[Central scotoma|central field defect]] in one eye  and temporal half-field defect in the other eye (not shown in the figure).<ref name="Khurana-NO">{{cite book |last1=Khurana |title=Comprehensive ophthalmology |publisher=Jaypee, The Health Sciences Publisher |isbn=978-93-5152-657-5 |pages=314–315 |edition=6th |chapter=Neuro-ophthalmology|date=31 August 2015 }}</ref>
*A lesion in the center of the [[optic chiasma]] causes [[bitemporal hemianopia]]<ref name="Khurana-NO" /> 
*A lesion to the [[optic tract]], or involving the complete [[optic radiation]] causes [[Homonymous hemianopsia|homonymous hemianopia]]
*When part of the optic radiation in the [[parietal lobe]] is affected, the resulting field defect may be inferior [[Quadrantanopia|quadrant hemianopia]]<ref name="Khurana-NO" />