The rostral basilar artery syndrome: diagnosis, etiology, prognosis.

Vascular occlusive disease of the rostral basilar artery (RBAS) causes a myriad of clinical signs and symptoms reflecting rostral brainstem-diencephalic and posterior hemispheric dysfunction. To help define the clinical profile, we prospectively studied 61 patients with clinical/neuroimaging evidence of RBAS during a 7-year period. Fourteen patients mirrored classic descriptions: severe visual, oculomotor and behavioral signs without prominent motoric dysfunction, uniformly poor prognosis, and intimate association with hypertension and prior episodes of vertebrobasilar ischemia (VBI). In contrast, 47 individuals had a reversible syndrome with excellent short-term functional recoveries, and were distinguished by a lower frequency and severity of hypertension, a greater incidence of arrhythmias in the young, and no history of VBI. All patients had important neurobehavioral abnormalities including an invariable acute confusional state. Diagnosis required the integrated assessment of neurobehavioral, ophthalmologic, and imaging tests. The clinical syndrome is more common and etiologically diverse than previously reported and is frequently unrecognized in the young and elderly who present with acute confusion.