Neuro-Ophthalmology at the Bedside: A Clinical Guide

Overview

This practical guide, published in the Journal of Neurosciences in Rural Practice in 2018, presents a basic neuro-ophthalmological examination. It can be performed in the emergency department or office with minimal equipment and little time. Neuro-ophthalmological signs are common in emergencies and often uncertain. Yet they frequently allow precise localisation of the problem and can be the first sign of serious brain or eye disease.

The examination

The guide starts with a structured history: onset and course, pain, whether the problem affects one or both eyes, medications, and what the patient means by blurred vision. Visual acuity is tested in each eye with a near card. Pupil examination includes the swinging flashlight test for afferent defects, and it distinguishes Horner syndrome, oculomotor palsy, tonic pupil and drug-induced dilation, using simple eye-drop tests where needed. Ptosis is assessed with the same three urgent causes in mind: third nerve palsy, Horner syndrome and myasthenia.

Eye movements are tested in nine directions, with simple rules for identifying the weak muscle and typical patterns of the abducens, oculomotor and trochlear nerves. The guide also covers saccades, pursuit, convergence and internuclear ophthalmoplegia. Further components are confrontation visual fields, fundoscopy, the Amsler grid and the optokinetic drum. Non-mydriatic fundus photography is presented as a promising alternative to the declining skill of direct ophthalmoscopy.

Urgent scenarios

For acute visual loss, the priorities are ischaemic optic neuropathy, giant cell arteritis (which needs immediate treatment mainly to protect the other eye) and optic neuritis. An acute Horner syndrome is treated as an emergency because of possible carotid dissection or brainstem stroke. A third nerve palsy with pupil involvement suggests compression. A table of red flags links key findings to serious causes.

Clinical implications

Vertical gaze disorders point to the midbrain and horizontal ones to the pons. Hemianopic field defects indicate a lesion behind the optic chiasm. The authors argue that a competent bedside examination makes diagnosis faster and more cost-effective by guiding the targeted use of imaging and other tests. They call for more practical teaching of these skills.