ABSTRACT
This chapter explores visual disorders that arise as a result of disease of the central nervous system where some understanding of ophthalmology is essential for diagnosis and management. It provides the background required to understand the implications of such conditions, beginning with measurement of the parameters of visual function and the techniques of examination. Visual acuity is defined as the minimum separabile, that is to say the minimum separation of two points that can be resolved by the visual system. A record of the best corrected visual acuity in each eye is essential to the assessment of a neuro-ophthalmic disorder. Visual acuity is exquisitely dependent upon the refractive state of the eye and the integrity of the ocular media. Assessment of the visual fields is an essential part of every neuro-ophthalmological examination. In the assessment of ocular motility disorders, it is necessary to establish the ocular alignment.
