Teaching NeuroImages: Acute Parinaud syndrome

An 82-year-old man with atrial fibrillation, nonadherent to rivaroxaban, presented with sudden bilateral ptosis. Examination demonstrated bilateral ptosis (figure 1), pupils midline, fixed midsize, not reactive to light but constricting to accommodation, impaired vertical eye movements, paresis of superior greater than inferior rectus, and upgaze convergence nystagmus. MRI showed infarction of bilateral third nerve nuclei and mesial thalami consistent with an artery of Percheron infarct (figure 2), presumed cardioembolic origin. Artery of Percheron is a single P1 branch that supplies the bilateral paramedian thalami and rostral midbrain. Infarcts may present with vertical gaze palsy, memory impairment, and impairment of arousal.1
Source: Neurology - Category: Neurology Authors: Tags: MRI, All Cerebrovascular disease/Stroke, Embolism, Infarction RESIDENT AND FELLOW SECTION Source Type: research