Remember the retina: retinal disorders presenting to neurologists.

General neurologists and stroke specialists are regularly referred cases of visual disturbance by general practitioners, emergency doctors and even ophthalmologists. Particularly when the referral comes from ophthalmologists, our assessment tends to focus on the optic nerve; however, retinal conditions may mimic optic neuropathy and are easily missed. Their diagnosis requires specific investigations that are rarely available in a neurology clinic.

Internuclear ophthalmoplegia.

A brainstem lesion of any type that involves the medial longitudinal fasciculus (MLF) can cause internuclear ophthalmoplegia (INO). This primarily affects conjugate horizontal gaze and classically manifests as impaired adduction ipsilateral to the lesion and abduction nystagmus contralateral to the lesion. Here, we describe the anatomy of the MLF and review the clinical features of INO.