Diagnostic Diplopia: Isolated Oculomotor Nerve Palsy With Normal Imaging

A 51-year-old man presented with progressive, subacute diplopia and ophthalmoplegia. Examination by the hospitalist demonstrated right ophthalmoplegia on left lateral gaze. No neurologist or neuro-ophthalmologist was available. Imaging and laboratory work were largely unremarkable. Although a microvascular etiology was suspected, the unremarkable workup expanded the differential diagnosis, highlighting the diagnostic and management challenges of cranial nerve III palsy when imaging is unremarkable in a community hospital with limited resources.