Background: Little is known about stroke mechanisms in patients with fluctuating symptoms and the role of branch atherosclerotic disease.
Objective: To report a novel stroke presentation associated with a paramedian pontine infarct due to branch disease with a fluctuating course.
Design: Case report.
Setting: Academic research. Patient A 63-year-old man with hypertension, diabetes mellitus, and dyslipidemia was seen with fluctuating right-sided weakness and dysarthria. He had had 2 episodes of complete bilateral horizontal conjugate gaze palsy with unimpaired consciousness lasting for 5 minutes each. His pupils were 4 mm and were equal and reactive to light. Vertical gaze and convergence were preserved. His neurologic status fluctuated between 3 and 15 on the National Institutes of Health Stroke Scale.
Main outcome measures: Results of computed tomographic angiography, perfusion, and magnetic resonance imaging.
Results: Intravenous tissue plasminogen activator was administered within a 3-hour window. Fluctuations in motor weakness persisted for 12 hours after receiving thrombolytic therapy. Neuroimaging showed an acute left paramedian pontine infarct with a patent basilar artery.
Conclusions: Branch disease is a common mechanism in pontine infarctions. We coined the term "pontine warning syndrome" to characterize recurrent stereotyped episodes of motor or sensory dysfunction, dysarthria, or ophthalmoplegia associated with a high risk of imminent basilar artery branch infarction and a permanent deficit resembling those of capsular warning syndrome.