1438 - Fatigue Masks Extensive Cranial Nerve Involvement of Suspected Eight-and-a-Half Syndrome

Case Diagnosis: Pontine and middle cerebellar peduncle intracerebral hemorrhage

Case Description: A 44-year-old female with untreated hypertension presented with sudden onset right-sided weakness and emesis. MRI demonstrated left pontine and middle cerebellar peduncle hemorrhage, acute infarcts of the bilateral cerebrum and left basal ganglia, and ischemia likely secondary to brainstem hemorrhage. Neurology diagnosed left eight-and-a-half syndrome. On rehabilitation admission, exam was limited by somnolence but revealed right hemiparesis, left facial droop, left-sided medial gaze fixation, severe dysphagia and dysarthria, and tremors. Therapies were limited by fatigue and impaired communication. She was started on amantadine, sleep protocol, delirium precautions, and comprehensive speech, occupational, and physical therapies. Her alertness and communication gradually improved. Repeat neurological examination was conducted when the patient was more participatory, which revealed greater brainstem involvement than initially detected. Findings included left-sided ataxia, left facial sensory impairment, and left-sided hearing loss.

Discussions: Eight-and-a-half syndrome is a rare neuro-ophthalmologic syndrome, typically diagnosed clinically but supported by MRI. The symptoms of conjugate horizontal gaze palsy, ipsilateral internuclear ophthalmoplegia, and ipsilateral facial palsy are caused by a lesion involving the abducens nucleus, fascicular portion of the facial nerve, and medial longitudinal fasciculus. When present, additional parts of the brain may also be impacted as a result of intracerebral hemorrhage. This patient demonstrated involvement of left trigeminal, abducens, facial, and vestibulocochlear nerves, and cerebellum. In cases initially complicated by lethargy and cognitive impairment, repeat examinations are needed to reveal the extent of neurological impairments.

Conclusions: This case shows the importance of repeating neurological examinations, especially in patients affected by significant lethargy soon after stroke. Identification of all deficits is important for developing targeted therapy programs and referring to appropriate providers, such as otolaryngology for hearing impairment. Identification of neurologic impairments should extend past diagnosis of a stroke syndrome. It is important to reevaluate patients throughout their recovery.