EHS is a rare neuro-ophthalmic syndrome characterized by conjugate horizontal gaze palsy, ipsilateral internuclear ophthalmoplegia (INO), and ipsilateral facial nerve palsy. We present two cases secondary to ischemic and hemorrhagic strokes.

49-year-old man with hypertension and diabetes presented with two-week diplopia and three-day right-sided facial droop, and dysarthria. Neurological examination showed a right INO  and right facial palsy. CT angiogram revealed atherosclerotic disease in the pontine basilar artery. Brain MRI showed a subacute ischemic lesion in the right dorsal pons. A 6-month follow-up showed mild diplopia self-corrected upon convergence.

41-year-old man with hypertension presented with 4 hours of right-sided facial droop, left-sided paresthesia, and dysarthria. Neurological examination revealed a right INO with right facial weakness. Brain MRI demonstrated a right lateral and posterior pontine hemorrhage. A 1-month follow-up showed mild diplopia with right facial droop.

The cases illustrate EHS after ischemic and hemorrhagic strokes. EHS results from a lesion affecting the ipsilateral PPRF, MLF, and the abducens nucleus at the level of the pons. The most common etiology is vascular, infarction or hemorrhage, followed by demyelinating conditions. EHS is a clinical diagnosis, but brain imaging can provide additional insights into the underlying etiology. Neuro-rehabilitation plays a crucial role in maximal recovery, most of it achieved within 9 months.

Isolated conjugate horizontal gaze palsy, with ipsilateral INO, and peripheral facial nerve palsy can occur together in EHS. A vascular lesion is the most common cause, but a thorough workup is needed to exclude other etiologies. It is important to recognize the clinical features to start prompt treatment. Risk factors should be identified to optimize best outcomes.