ABSTRACT
The presence of macular splitting or macular sparing homonymous hemianopias can aid differential diagnosis between visual cortex lesions and lesions located more anteriorly in the visual pathway. Visual field analysis can help to identify the likely area of visual pathway involved and provide precise guidance to the radiologist as to the specific areas to be imaged. Lesions in certain areas of the visual pathway may produce associated signs and symptoms specific to that site of lesion, for example postfixational blindness in optic chiasm lesions. Congruity is the extent of symmetry of the visual field defect in either eye and can only be assessed by direct comparison of the visual field results from either eye. Presence of fundus and optic disc pathology will typically indicate anterior visual pathway disease rather than retrochiasmal pathology. Arcuate visual field defect is caused by selective damage to the superior or inferior retinal nerve fibre bundles, and is typical of optic disc disease.
