Visual Field Defects

Visual Field Defects

Visual fields may be mapped clinically by confrontation testing. The exact pattern of visual field loss may have localizing value due to the retinotopic arrangement of fibers in the visual pathways: any unilateral area of restricted loss implies a pre-chiasmatic lesion (choroid, retina, optic nerve), although lesions of the anterior calcarine cortex can produce a contralateral monocular temporal crescent. Bilateral homonymous scotomata are post-chiasmal in origin; bilateral heteronymous scotomata may be seen with chiasmal lesions.
Topographically, typical visual field defects are:

Retina: monocular visual loss, altitudinal field defects; central or centrocecal scotoma, ring scotoma
Optic nerve: central or centrocecal Scotoma; junctional scotoma of Traquair
Optic chiasm: bitemporal hemianopia; junctional scotoma Optic tract: homonymous hemianopia, usually incongruous
Lateral geniculate nucleus: homonymous hemianopia, usually incongruous
Optic radiations: homonymous hemianopia, usually congruous; quadrantanopia
Visual cortex: homonymous hemianopia, usually congruous; quadrantanopia; cortical blindness

References

Hämäläinen HA, Julkunen LAM. Treatment of visual field defects after stroke. Advances in Clinical Neuroscience & Rehabilitation 2004; 3(6): 17-18
Schiefer U. Visual field defects: essentials for neurologists. Journal ofNeurology 2003; 250: 407-411
Trobe JD, Acosta PC, Krischer JP, Trick GL. Confrontation visual field techniques in detection of anterior visual pathway lesions. Annalsof Neurology 1981; 10: 28-34

Cross References

Altitudinal field defect; Hemianopia; Junctional scotoma, Junctional scotoma of traquair; Macula sparing, Macula splitting; Quadrantanopia; Scotoma