Visual fields in neuro-ophthalmology

Abstract

Visual field assessment is important in the evaluation of lesions involving the visual pathways and should be performed at baseline and periodically in the follow-up. Standard automated perimetry has been shown to be adequate in neuro-ophthalmic practise and is now the technique of choice for a majority of practitioners. Goldman kinetic visual fields are useful for patients with severe visual and neurologic deficits and patients with peripheral visual field defects. Visual fields are useful in monitoring progression or recurrence of disease and guide treatment for conditions such as idiopathic intracranial hypertension (IIH), optic neuropathy from multiple sclerosis, pituitary adenomas, and other sellar lesions. They are used as screening tools for toxic optic neuropathy from medications such as ethambutol and vigabatrin. Visual field defects can adversely affect activities of daily living such as personal hygiene, reading, and driving and should be taken into consideration when planning rehabilitation strategies. Visual field testing must be performed in all patients with lesions of the visual pathway.

Figure 1

Gray-scale and probability results in healthy subjects and patients with optic neuritis. Serial visual fields were performed either on the same day or different days. The two fields at the top of each graph are from 8 AM, the next pair down from 10 AM, etc. (a) Typical example of a normal subject’s consistent results. (b) A patient with optic neuritis with consistent results. (c, d) Variable results in patients with optic neuritis. Note the variation from near normal to near complete hemianopia (Reproduced with permission of the American Medical Association. From Wall et al.[14] Copyright © 1998. American Medical Association. All rights reserved.)

Figure 2

Visual field defects in idiopathic intracranial hypertension. (a) Enlarged blind spot. (b) Nasal step. (c) Biarcuate scotoma. (d) Severe visual field constriction

Figure 3

(a) Visual fields of a 38-year-old who complained of severe difficulty reading, shows a right inferior homonymous scotoma. (b) MRI brain of the same patient shows a lesion in the superior bank of the left calcarine cortex