A Rare Multinuclear Lesion Secondary to Multifactorial Ischemic Stroke: A Case Report on Eight-and-a-Half Syndrome

Internuclear ophthalmoparesis (INO) is a horizontal eye movement disorder that is associated with a lesion at the medial longitudinal fasciculus (MLF). One-and-a-half syndrome occurs when the lesion involves the MLF and the ipsilateral abducens nuclei or the paramedian pontine reticular formation (PPRF) in the dorsomedial tegmentum of the pons. When the lesion is large enough, the fascicles of the facial nerve (CNVII) can also be involved, resulting in an ipsilateral facial nerve palsy. In combination with one-and-a-half syndrome, this condition becomes eightand- a- half syndrome (EHS). Here, we describe a unique case of EHS in a 72-year-old male with multiple ischemic stroke risk factors who presented with INO, conjugate gaze palsy, ipsilateral facial palsy, and a transient contralateral hemiparesis. Recognizing this pattern of neurologic deficits improves localization of the lesion, prevents misdiagnosis of Bell's Palsy, and expedites proper treatment.