Do thalamic lesions really cause vertical gaze palsies?

Two patients with thalamic infarctions presented with vertical gaze palsies. Magnetic resonance imaging (MRI) demonstrated extension of the lesions into the upper midbrain. A common vascular supply to both areas, and the inability of computed tomography (CT) scans to adequately assess posterior fossa structures, necessitate MRI of the mesencephalon in the assessment of all patients with vertical gaze dysfunction. These cases shed further doubt regarding a specific role of the thalamus in control of vertical eye movements.