Eye movement abnormalities in Alzheimer disease: case presentation and literature review

To describe unusual eye movements in a patient with probable Alzheimer disease (AD) who presented with complaints of loss of balance and inability to read. In view of the increasing prevalence of AD in our aging population, it is also our purpose to review the literature regarding AD, as well as the reports of neuro-ophthalmic abnormalities.

Eye movement recordings were obtained using a RV-275 Saccadic Velocity Recorder (Tracousitics(®), Inc.). Horizontal saccades, ocular pursuit, optokinetic nystagmus, and eye movements while reading were recorded.

Eye movement recordings revealed the presence of saccadic dysmetria, pathologic small square wave jerks, saccadic pursuit, and irregular optokinetic nystagmus. Eye movements while reading were anomalous showing difficulty in the initiation of reading behaviour and poor stepwise progression through the text.

Inability to read is a frequent complaint in patients diagnosed with probable AD. In these cases, eye movements should be clinically assessed for subtle abnormalities and further assessment with eye movement recordings may reveal significant disruption in eye movement capability.