Assessment of the pupils includes the direct, consensual and accommodative response, as well the swingingflashlight test, which assesses the presence of a relative afferent pupillary defect (RAPD). When light is shone into the normal eye, both pupils constrict, but when it is swung to the eye with the RAPD ‐ e.g. with optic neuritis ‐ both pupils dilate. This test is particularly useful in the presence of asymmetric optic nerve lesions. The full range of extraocular eye movement is examined, including the cover test, saccades, pursuit and presence of nystagmus. Fatiguability should be elicited if myasthenia is suspected and examination completed by a directed general neurological assessment. INVESTIGATIONS Specialized investigations include fundus fluorescein angiography and clinical electrophysiology, i.e. visual evoked potentials, electroretinography and electro-oculography. This may be supplemented by Doppler ultrasound (for carotid artery stenosis), computed tomography, magnetic resonance imaging and cerebral angiography. NEURO-OPHTHALMIC DISEASE The range of neuro-ophthalmic disease is diverse, but the scope of this article only allows discussion of the commoner examples of such disorders. Demyelinating disease